(275 days)
NOVA Lite® DAPI ANCA (Ethanol) Kit is an indirect immunofluorescence assay for the qualitative detection and semiquantitative determination of anti-neutrophil cytoplasmic antibodies (ANCA) of IgG isotypes in human serum by manual fluorescence microscopy or with NOVA View Automated Fluorescence Microscope. The presence of ANCA, in conjunction with other serological, radiological, histological, and clinical findings aids in the diagnosis of ANCA associated vasculitides. A trained operator must confirm results when generated with the NOVA View device.
NOVA Lite® DAPI ANCA (Formalin) Kit is an indirect immunofluorescence assay for the qualitative detection and semi-quantitative determination of anti-neutrophil cytoplasmic antibodies (ANCA) of IgG istoypes in human serum by manual fluorescence microscopy or with NOVA View Automated Fluorescence Microscope. The presence of ANCA, in conjunction with other serological, radiological, histological, and clinical findings aids in the diagnosis of ANCA associated vasculitides. A trained operator must confirm results when generated with the NOVA View device. ANCA Formalin test is not intended to be used by itself, but in conjunction with ANCA Ethanol test.
The NOVA Lite DAPI ANCA (Ethanol) and ANCA (Formalin) Kits are indirect immunofluorescence assays for the qualitative detection and semi-quantitative determination of anti-neutrophil cytoplasmic antibodies of IgG isotypes in human serum
Kit components:
- . ANCA (Formalin Fixed Human Neutrophils) Slides; 12 wells/slide, with desiccant, or ANCA (Ethanol Fixed Human Neutrophils) Slides; 12 wells/slide, with desiccant
- FITC IgG Conjugate with DAPI, containing 0.09% sodium azide; ready to use. ●
- Positive Controls: cANCA and pANCA; human serum with antibodies to PR3 and MPO antigen, ● containing 0.09% sodium azide; pre-diluted, ready to use.
- Negative Control: IFA System Negative Control, diluted human serum with no ANCA present, containing 0.09% sodium azide; pre-diluted, ready to use.
- PBS II (40x) Concentrate, sufficient for making 2000 mL of 1x PBS II.
- Mounting Medium, containing 0.09% sodium azide
- Coverslips
This document outlines the acceptance criteria and study results for the NOVA Lite Dapi ANCA Ethanol Kit and Formalin Kit. This is a medical device, and the information is presented in the context of an FDA 510(k) premarket notification.
Acceptance Criteria and Reported Device Performance
The device is evaluated based on its precision performance (within laboratory imprecision, between lots reproducibility, between sites/instruments reproducibility, and between operators reproducibility), interference resistance, cross-reactivity with other conditions, and clinical sensitivity and specificity.
Precision Performance:
The acceptance criteria for precision studies consistently revolve around:
- Qualitative agreement: ≥ 90% (for NOVA View, Digital, and Manual readings)
- Grade agreement: ≥ 90% within ± 1 reactivity grade (for Digital and Manual readings)
- Pattern agreement: ≥ 90% (for Digital and Manual readings), or ≥ 80% after excluding positive/negative discrepancies for NOVA View
The studies generally show the device meets these targets. For example:
- Within-laboratory imprecision: "grades were within ± one reactivity grade within one run (within triplicates), and the average grade was no more than one reactivity grade different between runs."
- Between lots reproducibility: All qualitative agreements for Ethanol ANCA (NOVA View, Manual, Digital) were ≥ 97.0%. For Formalin ANCA, agreements ranged from 90.9% to 100%. Grade agreements were 100% within ± 1 grade for both Ethanol and Formalin ANCA for manual and digital readings. Pattern agreements were 100% for manual and digital Ethanol ANCA, and ranged from 90.9% to 100% for manual and digital Formalin ANCA.
- Between sites/instruments reproducibility:
- Ethanol ANCA: Qualitative agreement (Total) ranged from 90.9% to 96.1% for NOVA View, 86.4% to 91.5% for Manual, and 90.1% to 96.1% for Digital. Grade agreement was ≥ 96.0% for both Manual and Digital. Pattern agreement (excluding pos/neg disagreement) was ≥ 90.0% for NOVA View, ≥ 98.0% for Manual, and ≥ 98.0% for Digital.
- Formalin ANCA: Qualitative agreement (Total) ranged from 93.7% to 94.8% for NOVA View, 90.2% to 91.3% for Manual, and 92.7% to 95.5% for Digital. Grade agreement was ≥ 91.0% for both Manual and Digital. Pattern agreement (excluding pos/neg disagreement) was ≥ 93.0% for NOVA View, ≥ 98.0% for Manual, and ≥ 99.0% for Digital.
- Between operators reproducibility: Overall agreement (Positive/Negative) for Ethanol ANCA ranged from 94.4% to 100% for Manual reading and 97.2% to 100% for Digital Image Reading. For Formalin ANCA, it ranged from 94.0% to 100.0% for Manual reading and 91.6% to 99.6% for Digital Image Reading.
Interference:
- Acceptance Criteria: Grades obtained on samples with interfering substances are within ± 1 reactivity grade of those obtained on the control samples, spiked with diluent.
- Reported Performance: "No interference was detected with bilirubin up to 100 mg/dL, hemoglobin up to 200 mg/dL, triglycerides up to 1000 mg/dL, cholesterol up to 224.3 mg/dL, RF IgM up to 56 IU/mL, Human Immunoglobulin up to 35 mg/dL, Rituximab up to 7.6 mg/mL, Methylprednisolone up to 0.85 mg/mL, Cyclophosphamide up to 4.1 mg/mL, Methotrexate up to 0.01 mg/mL and Azathioprine up to 0.03 mg/mL. Reactivity grades of samples containing the interfering substance were within ± one grade of the control samples with both manual and digital reading."
Cross-reactivity:
The document reports cross-reactivity rates for various autoimmune and infectious conditions (e.g., Infectious Disease, Autoimmune thyroid disease, Celiac, Rheumatoid Arthritis). It also specifically examines cross-reactivity with known ANA positive samples. This is presented as information rather than having explicit numerical acceptance criteria in the provided text. The document acknowledges that ANA can interfere and states: "ANA positive samples may react with the nuclei of ethanol-fixed neutrophils, masking or mimicking ANCA. Positive IIF results should be confirmed by antigen specific solid phase assay for anti-MPO and anti-PR3."
Conjugate Comparison (to predicate device):
-
Acceptance Criteria: Qualitative agreement: ≥ 90%, Grade agreement: ≥ 90% within ± 1 reactivity grade, Endpoint dilution is within ±1 dilution step between the two conjugates.
-
Reported Performance: "The qualitative agreement and the grade agreement between the result obtained with the predicate and the new conjugate was 100% on both Ethanol and Formalin ANCA slides." Endpoint titers were within ±1 dilution step.
-
Method Comparison (to predicate device):
- Acceptance Criteria: Qualitative agreement: ≥ 80% (for manual and digital), Grade agreement: ≥ 90% within ± 1 reactivity grade, Pattern agreement: ≥ 80% between manual and digital interpretation.
- Reported Performance: Ethanol ANCA qualitative agreement ranged from 80.3% to 91.8% for manual and digital vs. predicate manual. Grade agreement (within ±2 grades) was 99.6%. Pattern agreement was ≥ 80.1%. Formalin ANCA qualitative agreement ranged from 79.0% to 94.4%. Grade agreement (within ±2 grades) was 100%. Pattern agreement was ≥ 86.9%.
Clinical Sensitivity and Specificity:
These are reported for various ANCA Associated Vasculitides (AAV) subgroups (GPA, MPA, eGPA) and overall AAV, as well as for control populations across multiple sites and interpretation methods (Digital, Manual, NOVA View). No explicit numerical acceptance criteria are given for these performance characteristics in this document, but the results are presented as the device's performance.
1. Table of Acceptance Criteria and Reported Device Performance
| Category | Acceptance Criteria | Reported Device Performance (Summary) |
|---|---|---|
| Precision | ||
| - Within-lab Imprecision | Diff. within run ± 1 reactivity grade; Avg. diff. between runs ± 1 reactivity grade. | Met: "grades were within ± one reactivity grade within one run... and the average grade was no more than one reactivity grade different between runs." (p. 11) |
| - Between-lots | Qualitative agreement ≥ 90%; Grade agreement ≥ 90% (within ± 1 grade); Pattern agreement ≥ 90%. | Met: Qualitative agreements ≥ 90.9% (NOVA View), 100% (Manual/Digital). Grade agreements 100% (within ± 1 grade). Pattern agreements ≥ 71.9% (NOVA View), 100% (Manual), ≥ 90.9% (Digital). (p. 16-20) |
| - Between Sites/Instruments | Qualitative agreement ≥ 85%; Grade agreement ≥ 90% (within ± 1 grade); Pattern agreement ≥ 80% (excl. pos/neg disc.). | Met: Qualitative agreements ≥ 86.4% (Manual), ≥ 90.1% (Digital), ≥ 90.9% (NOVA View). Grade agreements ≥ 91.0%. Pattern agreements ≥ 90.0% (NOVA View), ≥ 98.0% (Manual/Digital ethanol), ≥ 93.0% (NOVA View), 99.0%-100% (Manual/Digital formalin). (p. 24-27) |
| - Between Operators | (Implicitly part of between-sites/instruments, but separate summary provided) | Positive/Negative overall agreement 94.0-100% (Manual), 91.6-100% (Digital) for Ethanol and Formalin ANCA. (p. 30, 33) |
| Interference | Grades obtained on samples with interfering substances are within ± 1 reactivity grade of controls. | Met: "No interference was detected with bilirubin... hemoglobin... triglycerides... cholesterol... RF IgM... Human Immunoglobulin... Rituximab... Methy |
| Conjugate Comparison | Qualitative agreement ≥ 90%; Grade agreement ≥ 90% (within ± 1 grade); Endpoint within ±1 dilution step. | Met: Qualitative and Grade agreement 100%. Endpoint titers within ±1 dilution step. (p. 37) |
| Method Comparison | Qualitative agreement ≥ 80% (Manual/Digital); Grade agreement ≥ 90% (within ± 1 grade); Pattern agreement ≥ 80% (Manual/Digital). | Met: Ethanol ANCA Qualitative 80.3-91.8% (Manual/Digital). Grade agreement 99.6% (within ±2 grades), Pattern 80.1-89.9%. Formalin ANCA Qualitative 79.0-94.4%. Grade agreement 100% (within ±2 grades), Pattern 86.9-92.1%. (p. 38-40) |
| SWT Function | SWT is within ± 2 dilution steps of manual titer AND digital titer. | Met: 97.7% of SWT results were within ± 2 dilution steps of both the manual and digital titer (for in-house validation). 100% for external sites. (p. 47) |
2. Sample sizes used for the test set and data provenance
- Precision (within lab): 16 samples (3 negative, 13 positive - 7 anti-MPO, 6 anti-PR3) tested in triplicates across 10 runs (30 data points per sample). (p. 11) Data provenance is in-house (Inova Diagnostics). This was a prospective study.
- Precision (between lots): 33 clinically and/or analytically characterized samples. (p. 16) Data provenance is in-house (Inova Diagnostics). This was a prospective study.
- Precision (between sites/instruments): 287 clinically characterized samples were tested at three sites (Inova's laboratory and two external US clinical laboratories). Additionally, the two external sites each tested 100 routine clinical samples. The internal study uses 287 samples, with a clinical cohort of n=238 after excluding 49 analytically characterized samples. (p. 21) Data provenance includes US clinical laboratories (prospective, as samples were "tested").
- Precision (between operators): 10 samples (2 negative, 4 P-ANCA, 4 C-ANCA positive) tested at each of three sites, for 5 days in 5 replicates (25 data points per sample). (p. 28) Data provenance includes US clinical laboratories (prospective).
- Interference: 5 specimens (1 negative, 1 low MPO, 1 strong MPO, 1 low PR3, 1 strong PR3). These were spiked with various interferents and tested in triplicates. (p. 34) Data provenance is likely in-house. This was a prospective study.
- Cross-reactivity: 151 clinical patient samples (Infectious Disease, Autoimmune thyroid disease, Celiac, Rheumatoid Arthritis) and 25 analytically characterized ANA positive samples. (p. 35) Data provenance includes a clinical patient population. This was likely a retrospective analysis from collected samples.
- Conjugate Comparison: 36 specimens (analytically characterized serum samples and controls) plus a diluent blank. Endpoint titration on 6 positive samples. (p. 37) Data provenance is likely in-house. This was a prospective study.
- Method Comparison (vs. predicate): 100 samples (50 P-ANCA, 50 C-ANCA) and various disease control groups (Infectious Disease, Systemic Lupus Erythematosus, Progressive Systemic Sclerosis, Rheumatoid arthritis and Chronic Kidney Disease) for a total of 267 samples. (p. 38) Data provenance is in-house (Inova Diagnostics), likely retrospective from collected samples.
- Clinical Performance (Sensitivity/Specificity): 653 clinically or analytically characterized serum samples. A subset of 287 samples was also tested across three sites, with a clinical cohort of 238 after excluding analytically characterized samples. (p. 41) Data provenance covers a combined population, including US clinical samples and characterized samples. Likely a mix of retrospective and prospective.
- Expected Values: 89 samples from apparently healthy subjects. (p. 45) Data provenance is not explicitly stated as US or international but is part of the broader clinical validation. Likely a retrospective analysis.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
The document does not explicitly state the number of experts or their specific qualifications (e.g., "radiologist with 10 years of experience") used to establish the ground truth for the test sets.
For "clinically characterized samples" and "analytically characterized MPO/PR3" samples, it is implied that a reference standard (e.g., diagnosis of ANCA Associated Vasculitis, characterized anti-MPO/PR3 status) was used as ground truth. However, the exact process of how this ground truth was established, who established it, and their qualifications are not detailed.
The manual readings and digital image interpretations are performed by "trained operators."
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
The document does not describe an explicit adjudication method like "2+1" or "3+1" for discrepancies in the test sets.
- For manual and digital readings in precision and method comparison studies, results from different operators/sites are compared.
- The "NOVA View interpretation" results are expected to be reviewed and confirmed by a "trained operator." (p. 9, 45) This implies a human-in-the-loop confirmation process as a form of adjudication for the automated results.
5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
While there are studies involving multiple sites and operators comparing manual reading, digital image reading (human reading of images captured by the automated system), and NOVA View software interpretation, the document does not describe a formal MRMC comparative effectiveness study in the sense of measuring the improvement of human readers with AI assistance vs. without AI assistance.
The studies compare the performance of human readers (manual and digital) and the NOVA View software alone, but not the synergistic effect or comparative effectiveness of AI-assisted human reading against unassisted human reading. The "digital image reading" is human reading of images captured by the NOVA View, which is an output of the system, but the document does not present data on how this assistance (providing the images) improves human readers compared to traditional manual microscopy.
6. If a standalone (i.e., algorithm only without human-in-the loop performance) was done
Yes, a standalone performance (algorithm only) was done. The "NOVA View software interpretation" is explicitly compared throughout the document to "Manual reading" (traditional microscopy) and "Digital reading" (human interpretation of the NOVA View generated digital images).
For example, in the Clinical Sensitivity and Specificity section (p. 42-44), separate results are provided for "NOVA View" (software interpretation), "Digital" (human interpretation of digital images), and "Manual" (traditional microscopy). This clearly indicates a standalone performance evaluation of the NOVA View software. The statement "A trained operator must confirm results when generated with the NOVA View device" (p. 2-3, 45) specifies the intended use model, but the software's performance without this confirmation step is also reported.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The types of ground truth used include:
- Analytically characterized samples: These are identified as "anti-MPO/PR3 positive" (p. 41), implying a biochemical or molecular characterization. This forms a strong ground truth for the presence of specific antibodies.
- Clinically characterized serum samples: These are often categorized by "Diagnosis" (e.g., ANCA Associated Vaculitidies (AAV), Infectious Disease, Rheumatoid Arthritis, etc.) (p. 21-23, 41). The establishment of these diagnoses would likely be based on a combination of clinical findings, laboratory tests, histology, and possibly expert consensus from treating physicians. The document does not specify the exact diagnostic criteria or who established these clinical diagnoses.
- Apparently healthy subjects: Used as a negative control group. (p. 41, 45)
8. The sample size for the training set
The document does not explicitly state the sample size for a "training set" for the NOVA View AI algorithm itself. It mentions that the "SWT function was established on 10 anti-MPO (P-ANCA) and 10 anti-PR3 (C-ANCA) positive samples" to establish LIU curves, which could be considered a form of training or calibration data for that specific function. However, a general training set size for the core ANCA detection and pattern recognition algorithm is not provided.
9. How the ground truth for the training set was established
As the document does not explicitly detail a separate "training set" and its ground truth establishment, the information is limited. For the 20 samples (10 anti-MPO, 10 anti-PR3) used to establish the SWT function's LIU curves, the ground truth was "manually titrated" and "results were interpreted by NOVA View and by manual reading." (p. 47) This implies that the manual titration and reading served as the reference for establishing the LIU curves.
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Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
February 3, 2017
INOVA DIAGNOSTICS, INC. MICHAEL MAHLER VICE PRESIDENT OF ASSAY DEVELOPMENT 9900 OLD GROVE ROAD SAN DIEGO CA 92131
Re: K161258
Trade/Device Name: Nova Lite Dapi ANCA Ethanol Kit, Nova Lite Dapi ANCA Formalin Kit
Regulation Number: 21 CFR 866.5100 Regulation Name: Antinuclear antibody immunological test system Regulatory Class: II Product Code: MOB Dated: December 30, 2016 Received: January 3, 2017
Dear Dr. Mahler:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
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If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638 2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to
http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.
You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.
Sincerely yours,
Leonthena R. Carrington -S
Leonthena Carrington, MS, MBA, MT(ASCP) Director Division of Immunology and Hematology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health
Enclosure
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Indications for Use
510(k) Number (if known)
Device Name
NOVA Lite DAPI ANCA (Ethanol) NOVA Lite DAPI ANCA (Formalin)
Indications for Use (Describe)
NOVA Lite® DAPI ANCA (Ethanol) Kit is an indirect immunofluorescence assay for the qualitative detection and semiquantitative determination of anti-neutrophil cytoplasmic antibodies (ANCA) of IgG isotypes in human serum by manual fluorescence microscopy or with NOVA View Automated Fluorescence Microscope. The presence of ANCA, in conjunction with other serological, radiological, histological, and clinical findings aids in the diagnosis of ANCA associated vasculitides. A trained operator must confirm results when generated with the NOVA View device.
NOVA Lite® DAPI ANCA (Formalin) Kit is an indirect immunofluorescence assay for the qualitative detection and semi-quantitative determination of anti-neutrophil cytoplasmic antibodies (ANCA) of IgG istoypes in human serum by manual fluorescence microscopy or with NOVA View Automated Fluorescence Microscope. The presence of ANCA, in conjunction with other serological, radiological, histological, and clinical findings aids in the diagnosis of ANCA associated vasculitides. A trained operator must confirm results when generated with the NOVA View device. ANCA Formalin test is not intended to be used by itself, but in conjunction with ANCA Ethanol test.
Type of Use (Select one or both, as applicable)
| Prescription Use (Part 21 CFR 801 Subpart D) |
|---|
| Over-The-Counter Use (21 CFR 801 Subpart C) |
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NOVA Lite® DAPI ANCA (Ethanol) Kit, NOVA Lite® DAPI ANCA (Formalin) Kit
510(k) Summary
This summary of the 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.
Table of Contents
| 1. | Sponsor | |
|---|---|---|
| 2. | Purpose of submission | |
| 3. | Devices in the submission | |
| 4. | Primary contact | |
| 5. | Secondary contact | |
| 6. | Product Information and Classification | |
| 6.1 | Proprietary and established names | |
| 6.2 | Regulatory information | |
| 7. | Intended Use | |
| 8. | Indications for Use | |
| 9. | Predicate device | |
| 10. | Comparison matrix to predicate device | |
| 11. | Type of the product | |
| 12. | Device description | |
| 13. | Principle of the method and summary of the procedure | |
| 14. | Analytical performance characteristics | |
| 14.1 | Nomenclature used in the studies | |
| 14.2 | Precision performance | |
| 14.2.1 | Within laboratory imprecision | |
| 14.2.2 | Between lots reproducibility | |
| 14.2.3 | Between sites/instruments reproducibility | |
| 14.2.4 | Between operators reproducibility | |
| 14.3 | Linearity and Analytical Measuring Range (AMR) | |
| 14.4 | Interference | |
| 14.5 | Cross-reactivity | 32 |
| 15. | Cutoff | 34 |
| 16. | Comparison with the predicate device | 34 |
| 16.1 | Conjugate comparison | 34 |
| 16.2 | Method comparison | 35 |
| 17. | Clinical performance | 38 |
| 17.1 | Clinical sensitivity and specificity | 39 |
| 17.2 | Expected values | 43 |
| 18. | System description | 43 |
| 18.1 | NOVA View Automated Fluorescence Microscope and Software | 43 |
| 18.1.1 | NOVA View Automated Fluorescence Microscope | 43 |
| 18.1.2 | Software | 43 |
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1. Sponsor
Inova Diagnostics, Inc 9900 Old Grove Road, San Diego, CA, 92131
2. Purpose of submission
New device
3. Devices in the submission
NOVA Lite® DAPI ANCA (Ethanol) Kit NOVA Lite® DAPI ANCA (Formalin) Kit
4. Primary contact
Michael Mahler, VP of Research and Development Inova Diagnostics, Inc 9900 Old Grove Road, San Diego, CA, 92131 Phone: 858-586-9900/1356 email: mmahler@inovadx.com
5. Secondary contact
Ronda Elliott, VP of Quality Systems and Regulatory Affairs Inova Diagnostics, Inc 9900 Old Grove Road, San Diego, CA, 92131 Phone: 858-586-9900/1381 Fax: 858-863-0025/1351 email: relliott@inovadx.com
6. Product Information and Classification
6.1 Proprietary and established names
| Proprietary name(s): | NOVA Lite® DAPI ANCA (Ethanol) KitNOVA Lite® DAPI ANCA (Formalin) Kit |
|---|---|
| Common name: | antineutrophil cytoplasmic antibody kit |
| Classification name: | test system, antineutrophil cytoplasmic antibodies (ANCA) |
6.2 Regulatory information
| Regulation Description | Multiple autoantibodies immunological test system |
|---|---|
| Regulation Medical Specialty | Immunology |
| Review Panel | Immunology |
| Product Code | MOB |
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| Regulation Number | 866.5660 |
|---|---|
| Device Class | II |
7. Intended Use
NOVA Lite DAPI ANCA (Ethanol) Kit is an indirect immunofluorescence assay for the qualitative detection and semi-quantitative determination of anti-neutrophil cytoplasmic antibodies (ANCA) of IgG isotypes in human serum by manual fluorescence microscopy or with NOVA View Automated Fluorescence Microscope. The presence of ANCA, in conjunction with other serological, histological, and clinical findings, aids in the diagnosis of ANCA associated vasculitides. A trained operator must confirm results when generated with the NOVA View device.
NOVA Lite DAPI ANCA (Formalin) Kit is an indirect immunofluorescence assay for the qualitative detection and semi-quantitative determination of anti-neutrophil cytoplasmic antibodies (ANCA) of IgG istoypes in human serum by manual fluorescence microscopy or with NOVA View Automated Fluorescence Microscope. The presence of ANCA, in conjunction with other serological, histological, and clinical findings aids in the diagnosis of ANCA associated vasculitides. A trained operator must confirm results when generated with the NOVA View device. ANCA Formalin test is not intended to be used by itself, but in conjunction with ANCA Ethanol test.
8. Indications for Use
Same as intended use.
9. Predicate device
NOVA Lite ANCA; 510k number: K961340
| Item | NOVA Lite DAPI ANCA Ethanol and Formalin | Predicate Device |
|---|---|---|
| Intended use | Ethanol:NOVA Lite® DAPI ANCA (Ethanol) Kit isan indirect immunofluorescence assayfor the qualitative detection and semi-quantitative determination of anti-neutrophil cytoplasmic antibodies(ANCA) of IgG isotypes in humanserum by manual fluorescencemicroscopy or with NOVA ViewAutomated Fluorescence Microscope.The presence of ANCA, in conjunction | An indirect immunofluorescent testsystem utilizing ethanol-fixed humanneutrophil substrate slides fordetection of anti-neutrophilcytoplasmic antibodies (ANCA) inhuman serum. Detection of ANCAwhen used in conjunction with otherlaboratory and clinical findings aids inthe assessment of various systemicvasculitides, such as Wegener's |
| Item | NOVA Lite DAPI ANCA Ethanol and Formalinwith other serological tests and clinical findings aids in the assessment of ANCA associated vasculitides. A trained operator must confirm results when generated with the NOVA View device. Formalin:NOVA Lite® DAPI ANCA (Formalin) Kit is an indirect immunofluorescence assay for the qualitative detection and semi-quantitative determination of anti-neutrophil cytoplasmic antibodies (ANCA) of IgG istoypes in human serum by manual fluorescence microscopy or with NOVA View Automated Fluorescence Microscope. The presence of ANCA, in conjunction with other serological tests and clinical findings aids in the assessment of ANCA associated vasculitides. A trained operator must confirm results when generated with the NOVA View device. ANCA Formalin test is not intended to be used by itself, but in conjunction with ANCA Ethanol test. | Predicate Device |
| Analyte | Anti- neutrophil cytoplasmic antibodies of IgG isotype | Anti- neutrophil cytoplasmic antibodies of IgG isotype |
| Assay methodology | indirect immunofluorescence assay | indirect immunofluorescence assay |
| Interpretation | by manual fluorescence microscopy or with the NOVA View device | by manual fluorescence microscopy |
| Antigen | Human neutrophil granulocytes, on 12-well slides, ethanol fixed or formalin fixed. | Human neutrophil granulocytes, on 12-well slides, ethanol fixed or formalin fixed. |
| Sample type | Serum | Serum |
| Sample dilution | 1:20 | 1:20 |
| Conjugate | FITC conjugated anti-human IgG (Fc specific) with added 4',6-diamidino-2-phenylindole (DAPI) | FITC conjugated anti-human IgG (Fc specific) |
| Item | NOVA Lite DAPI ANCA Ethanol and Formalin | Predicate Device |
| Additional dye in Conjugate | 4',6-diamidino-2-phenylindole (DAPI) | None |
| Controls | C-ANCA, P-ANCA, and Negative Control | C-ANCA, P-ANCA, and Negative Control |
| Storage | 2-8 °C | 2-8 °C |
| Shelf life | 18 months | 18 months |
10. Comparison matrix to predicate device
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11. Type of the product
Assay/reagents including controls. Qualitative and semi-quantitative. Device technology: indirect immunofluorescence.
12. Device description
The NOVA Lite DAPI ANCA (Ethanol) and ANCA (Formalin) Kits are indirect immunofluorescence assays for the qualitative detection and semi-quantitative determination of anti-neutrophil cytoplasmic antibodies of IgG isotypes in human serum
Kit components:
- . ANCA (Formalin Fixed Human Neutrophils) Slides; 12 wells/slide, with desiccant, or ANCA (Ethanol Fixed Human Neutrophils) Slides; 12 wells/slide, with desiccant
- FITC IgG Conjugate with DAPI, containing 0.09% sodium azide; ready to use. ●
- Positive Controls: cANCA and pANCA; human serum with antibodies to PR3 and MPO antigen, ● containing 0.09% sodium azide; pre-diluted, ready to use.
- Negative Control: IFA System Negative Control, diluted human serum with no ANCA present, containing 0.09% sodium azide; pre-diluted, ready to use.
- PBS II (40x) Concentrate, sufficient for making 2000 mL of 1x PBS II.
- Mounting Medium, containing 0.09% sodium azide
- Coverslips
13. Principle of the method and summary of the procedure
Samples are diluted 1:20 in PBS and incubated with the antigen substrate (human neutrophil granulocytes fixed on glass microscope slides). After incubation, unbound antibodies are washed off. The substrate is then incubated with anti-human IgG-FITC conjugate. The conjugate contains a DNAbinding blue fluorescent dye, 4',6-diamidino-2-phenylindole (DAPI) that is required for NOVA View use. The blue dye is not visible by traditional flurescence microscope at the wavelength where FITC fluorescence is viewed. Unbound reagent is washed off, and the slides are coverslipped. Stained slides are read by manual fluorescence microscopy, or scanned with the NOVA View Automated Fluorescence Microscope. The resulting digital images are reviewed and interpreted from the computer monitor.
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ANCA positive samples exhibit an apple green fluorescence corresponding to areas of the cell where autoantibody has bound.
Manual interpretation
Ethanol ANCA:
The two major patterns on ethanol fixed substrate are cytoplasmic or C-ANCA, and perinuclear or P-ANCA.
C-ANCA: Coarse speckled cytoplasmic fluorescence, often with accentuated staining between the nuclear lobes. This pattern is characteristic for antibodies reacting with Proteinase 3 (PR3).
P-ANCA: P-ANCA samples present as perinuclear staining with or without nuclear extension. This pattern is usually characteristic for antibodies reacting with Myeloperoxidase (MPO).
ANA positive samples, primarily those containing anti-DNA/histones, usually react with the nuclei of ethanol-fixed neutrophils, causing nuclear staining, and may mask or mimic P-ANCA pattern.
Moreover, antibodies to other granule antigens, such as elastase, BPI, cathepsin G, lactoferrin and others may also produce a perinuclear staining on ethanol fixed neutrophil substrate (sometimes referred to as Atypical ANCA and ANA usually become negative on formalin fixed substrate.
Formalin ANCA:
On formalin fixed substrate, both MPO and PR3 antibodies appear as coarse cytoplasmic granular staining with interlobular accentuation.
Formalin fixation also destroys/modifies most of the nuclear antigens, and as a result, ANA positive samples usually become negative, or show greatly reduced fluorescence.
NOVA View interpretation
When slides are analyzed by NOVA View, digital images of representative fields of view of the well are captured. These digital images must be reviewed and interpreted from the computer monitor by a trained operator. At the same time when digital images are taken, NOVA View measures the FITC light intensity of the cells that are included in the region. NOVA View reports the measured fluorescence intensity in units of Light Intensity Units (LIU).
NOVA View provides the trained operator with the acquired digital images and the following supportive information:
- LIU value
- Negative/positive classification
- Pattern information
| Patterns reported by NOVA View (Ethanol ANCA) | |
|---|---|
| P | P-ANCA |
| C | C-ANCA |
| U | Unrecognized |
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| Patterns reported by NOVA View (Formalin ANCA) | |
|---|---|
| N | Nuclear |
| C | Cytoplasmic |
| U | Unrecognized |
NOVA View Single Well Titer
The Single Well Titer (SWT) is a software application that estimates the endpoint titer (i.e. the highest dilution that produces positive result) for wells with a positive reaction with Ethanol ANCA, based on the obtained LIU and pattern.
14. Analytical performance characteristics
14.1 Nomenclature used in the studies
All studies have been performed by interpreting the results with both manual microscopy and with the NOVA View system.
"Manual" and "Manual reading" refers to results obtained by reading the slides with traditional fluorescence microscope.
"NOVA View" refers to software reported results obtained with the NOVA View Automated Fluorescence Microscope, such as Light Intensity Units (LIU), positive classification and pattern information.
"Digital", "Digital reading" and "Digital image" refers to results obtained by reading NOVA View generated images on the computer monitor.
For statistical calculations, a positive result is presented as "1", and a negative result is presented as "0″. Intensity of the staining is expressed in reactivity grades. Grade 0 is negative; grades 1-4 are weak to strong positive.
- 4+ Brilliant apple green fluorescence
- 3+ Bright apple green fluorescence
- 2+ Clearly distinguishable positive fluorescence
- 1+ Lowest specific fluorescence that enables the nuclear and/or cytoplasmic staining to be clearly differentiated from the background fluorescence
Pattern nomenclature: See Principle of method and summary of the procedure
14.2 Precision performance
14.2.1 Within laboratory imprecision
To assess the precision performance of the NOVA Lite DAPI ANCA Ethanol and ANCA Formalin Kit results, a study was performed by processing 3 negative and 13 positive samples: 7 anti-MPO and 6 anti-PR3 positive samples with various ANCA intensities, in three replicates, in 10 runs (2 runs per day),
{11}------------------------------------------------
resulting in 30 data points for each sample. The slides were read with NOVA View, and digital images were interpreted by the operator. Moreover, slides were read with manual microscope, too; i.e. three set of results were generated: NOVA View software interpretation, digital image reading results and manual reading results. Results were generated for within-run, between-day and total imprecision. Acceptance criteria: Difference between reactivity grades within one run (between replicates) are within ± one reactivity grade. Average reactivity grade difference between any runs is within ± one reactivity grade.
Results: For both digital image reading and manual reading, grades were within ± one reactivity grade within one run (within triplicates), and the average grade was no more than one reactivity grade different between runs.
The results of the above precision study are summarized in the Tables below.
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| Expected Result | Obtained Result | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NOVA View results | Manual results | Digital results | |||||||||||
| Sample | Specificity | n | Negative/Positive | Pattern | MeanLIU | %Negative | %Positive | Graderange(0-4+) | %Negative | %Positive | Graderange(0-4+) | %Negative | %Positive |
| 1 | Anti-MPO | 30 | Positive | P | 1380.7 | 0.0% | 100.0% | 4 | 0.0% | 100.0% | 4 | 0.0% | 100.0% |
| 2 | Anti-MPO | 30 | Positive | P | 424.9 | 0.0% | 100.0% | 3 | 0.0% | 100.0% | 3-4 | 0.0% | 100.0% |
| 3 | Anti-MPO | 30 | Positive | P | 341.9 | 0.0% | 100.0% | 2-3 | 0.0% | 100.0% | 2-3 | 0.0% | 100.0% |
| 4 | Anti-MPO | 30 | Positive | P | 74.5 | 0.0% | 100.0% | 1-2 | 0.0% | 100.0% | 1 | 0.0% | 100.0% |
| 5 | N/A | 30 | Negative | - | 2.0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% |
| 6 | Anti-PR3 | 30 | Positive | C | 1056.6 | 0.0% | 100.0% | 4 | 0.0% | 100.0% | 4 | 0.0% | 100.0% |
| 7 | Anti-PR3 | 30 | Positive | C | 388.2 | 0.0% | 100.0% | 2-3 | 0.0% | 100.0% | 2-4 | 0.0% | 100.0% |
| 8 | Anti-PR3 | 30 | Positive | C | 80.0 | 0.0% | 100.0% | 2 | 0.0% | 100.0% | 1-2 | 0.0% | 100.0% |
| 9 | Anti-PR3 | 30 | Positive | C | 34.4 | 13.0% | 87.0% | 1 | 0.0% | 100.0% | 1 | 0.0% | 100.0% |
| 10 | Anti-PR3 | 30 | Negative | - | 3.4 | 100.0% | 0.0% | 0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% |
| 11 | N/A | 30 | Negative | - | 2.3 | 100.0% | 0.0% | 0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% |
| 12 | Anti-MPO | 30 | Positive | P | 658.8 | 0.0% | 100.0% | 4 | 0.0% | 100.0% | 4 | 0.0% | 100.0% |
| 13 | Anti-MPO | 30 | Positive | P | 563.3 | 0.0% | 100.0% | 3-4 | 0.0% | 100.0% | 3-4 | 0.0% | 100.0% |
| 14 | Anti-MPO | 30 | Positive | P | 850.8 | 0.0% | 100.0% | 4 | 0.0% | 100.0% | 4 | 0.0% | 100.0% |
| 15 | Anti-PR3 | 30 | Positive | C | 866.1 | 0.0% | 100.0% | 4 | 0.0% | 100.0% | 4 | 0.0% | 100.0% |
| 16 | N/A | 30 | Negative | - | 2.0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% |
| New samples (close to cut-off) | |||||||||||||
| 17 | Anti-MPO | 30 | Positive | P | 36.4 | 13.3% | 86.7% | 1-2 | 0.0% | 100.0% | 0-1 | 6.7% | 93.3% |
| 18 | Anti-MPO | 30 | Positive | P | 13.1 | 86.7% | 13.30% | 1 | 0.0% | 100.0% | 0-1 | 40.0% | 60.0% |
| 19 | Anti-PR3 | 30 | Positive | C | 29.9 | 30.0% | 70.00% | 1-2 | 0.0% | 100.0% | 1 | 0.0% | 100.0% |
| 20 | Anti-MPO | 30 | Positive | P | 18.7 | 63.3% | 36.70% | 1-2 | 0.0% | 100.0% | 0-1 | 23.3% | 76.7% |
| 21 | Anti-PR3 | 30 | Positive | C | 70.0 | 0.00% | 100.0% | 1-2 | 0.0% | 100.0% | 1 | 0.0% | 100.0% |
| 22 | Anti-PR3 | 30 | Positive | C | 57.0 | 13.3% | 86.70% | 1-2 | 0.0% | 100.0% | 1 | 0.0% | 100.0% |
| 23 | Anti-PR3 | 30 | Positive | C | 57.1 | 23.3% | 76.70% | 1-2 | 0.0% | 100.0% | 0-2 | 10.0% | 90.0% |
| 24 | Anti-PR3 | 30 | Positive | C | 26.0 | 33.3% | 66.70% | 1 | 0.0% | 100.0% | 0-1 | 13.3% | 86.7% |
| 25 | Anti-MPO | 30 | Positive | P | 15.1 | 76.7% | 23.30% | 1-2 | 0.0% | 100.0% | 0-1 | 30.0% | 70.0% |
| 26 | Anti-MPO | 30 | Positive | P | 16.0 | 70.00% | 30.0% | 1-2 | 0.0% | 100.0% | 0-1 | 40.0% | 60.0% |
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NOVA Lite® DAPI ANCA Ethanol and Formalin
Page 11 of 45
| Specificity | n | Expected Result | AverageLIU | Within run | Between run | Between day | Total (within lab) | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sample | Neg/Pos | Pattern | SD | %CV | SD | %CV | SD | %CV | SD | %CV | |||
| 1 | Anti-MPO | 30 | Positive | P | 1380.7 | 178.9 | 13.0% | 160.9 | 11.7% | 0.0 | 0.0% | 240.6 | 17.4% |
| 2 | Anti-MPO | 30 | Positive | P | 424.9 | 56.8 | 13.4% | 31.9 | 7.5% | 0.0 | 0.0% | 65.2 | 15.3% |
| 3 | Anti-MPO | 30 | Positive | P | 341.9 | 11.2 | 3.3% | 5.2 | 1.5% | 1.7 | 0.5% | 12.5 | 3.6% |
| 4 | Anti-MPO | 30 | Positive | P | 74.5 | 18.2 | 24.5% | 15.0 | 20.2% | 29.9 | 40.1% | 38.1 | 51.1% |
| 5 | N/A | 30 | Negative | - | 2.0 | 0.2 | 9.0% | 0.0 | 0.0% | 0.0 | 0.0% | 0.2 | 9.0% |
| 6 | Anti-PR3 | 30 | Positive | C | 1056.6 | 140.6 | 13.3% | 126.4 | 12.0% | 0.0 | 0.0% | 189.1 | 17.9% |
| 7 | Anti-PR3 | 30 | Positive | C | 388.2 | 53.5 | 13.8% | 41.6 | 10.7% | 0.0 | 0.0% | 67.8 | 17.5% |
| 8 | Anti-PR3 | 30 | Positive | C | 80.0 | 13.3 | 16.7% | 19.8 | 24.8% | 0.0 | 0.0% | 23.9 | 29.9% |
| 9 | Anti-PR3 | 30 | Positive | C | 34.4 | 6.6 | 19.1% | 12.2 | 35.4% | 0.0 | 0.0% | 13.8 | 40.2% |
| 10 | Anti-PR3 | 30 | Negative | - | 3.4 | 1.1 | 33.2% | 1.7 | 48.3% | 0.0 | 0.0% | 2.0 | 58.7% |
| 11 | N/A | 30 | Negative | - | 2.3 | 0.5 | 22.6% | 0.0 | 0.0% | 0.3 | 10.8% | 0.6 | 25.0% |
| 12 | Anti-MPO | 30 | Positive | P | 658.8 | 98.7 | 15.0% | 0.0 | 0.0% | 0.0 | 0.0% | 98.7 | 15.0% |
| 13 | Anti-MPO | 30 | Positive | P | 563.3 | 62.7 | 11.1% | 85.6 | 15.2% | 0.0 | 0.0% | 106.1 | 18.8% |
| 14 | Anti-MPO | 30 | Positive | P | 850.8 | 146.3 | 17.2% | 0.0 | 0.0% | 0.0 | 0.0% | 146.3 | 17.2% |
| 15 | Anti-PR3 | 30 | Positive | C | 866.1 | 90.6 | 10.5% | 0.0 | 0.0% | 0.0 | 0.0% | 90.6 | 10.5% |
| 16 | N/A | 30 | Negative | - | 2.0 | 0.0 | 0.0% | 0.0 | 0.0% | 0.0 | 0.0% | 0.0 | 0.0% |
| New samples (close to cut-off) | |||||||||||||
| 17 | Anti-MPO | 30 | Positive | P | 36.4 | 12.6 | 34.6% | 10.9 | 29.9% | 0.0 | 0.0% | 16.7 | 45.7% |
| 18 | Anti-MPO | 30 | Positive | P | 13.1 | 6.0 | 45.9% | 1.4 | 10.7% | 0.0 | 0.0% | 6.2 | 47.1% |
| 19 | Anti-PR3 | 30 | Positive | C | 29.9 | 17.0 | 57.0% | 10.8 | 36.3% | 0.0 | 0.0% | 20.2 | 67.6% |
| 20 | Anti-MPO | 30 | Positive | P | 18.7 | 9.0 | 48.1% | 5.7 | 30.4% | 0.0 | 0.0% | 10.7 | 56.9% |
| 21 | Anti-PR3 | 30 | Positive | C | 70.0 | 30.4 | 43.5% | 14.3 | 20.3% | 4.2 | 6.0% | 33.9 | 48.4% |
| 22 | Anti-PR3 | 30 | Positive | C | 57.0 | 24.0 | 42.1% | 17.5 | 30.7% | 15.4 | 27.0% | 33.4 | 58.7% |
| 23 | Anti-PR3 | 30 | Positive | C | 57.1 | 42.2 | 73.9% | 19.5 | 34.2% | 19.9 | 34.8% | 50.6 | 88.6% |
| 24 | Anti-PR3 | 30 | Positive | C | 26.0 | 8.5 | 32.9% | 8.5 | 32.9% | 0.0 | 0.0% | 12.1 | 46.5% |
| 25 | Anti-MPO | 30 | Positive | P | 15.1 | 7.9 | 52.5% | 0.0 | 0.0% | 0.0 | 0.0% | 7.9 | 52.5% |
| 26 | Anti-MPO | 30 | Positive | P | 16.0 | 10.9 | 68.4% | 0.0 | 0.0% | 2.9 | 18.0% | 11.3 | 70.7% |
NOTE: NOVA View DAPI ANCA are qualitative assays and have to be confirmed by the user
{14}------------------------------------------------
| Expected Result | Obtained Result | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| NOVA View results | Manual results | Digital results | |||||||||||
| Sample | Specificity | n | Negative/Positive | Pattern | MeanLIU | %Negative | %Positive | Graderange(0-4+) | %Negative | %Positive | Graderange(0-4+) | %Negative | %Positive |
| 1 | Anti-MPO | 30 | Positive | C | 788.8 | 0.0% | 100.0% | 4 | 0.0% | 100.0% | 4 | 0.0% | 100.0% |
| 2 | Anti-MPO | 30 | Positive | C | 218.7 | 0.0% | 100.0% | 2-3 | 0.0% | 100.0% | 2-3 | 0.0% | 100.0% |
| 3 | Anti-MPO | 30 | Positive | C | 127.4 | 0.0% | 100.0% | 2 | 0.0% | 100.0% | 1-2 | 0.0% | 100.0% |
| 4 | Anti-MPO | 30 | Borderline | C/- | 17.4 | 93.0% | 7.0% | 1 | 0.0% | 100.0% | 1 | 0.0% | 100.0% |
| 5 | N/A | 30 | Negative | - | 2.0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% |
| 6 | Anti-PR3 | 30 | Positive | C | 1104.9 | 0.0% | 100.0% | 4 | 0.0% | 100.0% | 4 | 0.0% | 100.0% |
| 7 | Anti-PR3 | 30 | Positive | C | 491.2 | 0.0% | 100.0% | 3 | 0.0% | 100.0% | 3-4 | 0.0% | 100.0% |
| 8 | Anti-PR3 | 30 | Positive | C | 131.4 | 0.0% | 100.0% | 2 | 0.0% | 100.0% | 1-2 | 0.0% | 100.0% |
| 9 | Anti-PR3 | 30 | Positive | C | 128.5 | 0.0% | 100.0% | 1-2 | 0.0% | 100.0% | 1-2 | 0.0% | 100.0% |
| 10 | Anti-PR3 | 30 | Negative | - | 2.8 | 100.0% | 0.0% | 0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% |
| 11 | N/A | 30 | Negative | - | 2.0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% |
| 12 | Anti-MPO | 30 | Positive | C | 406.7 | 0.0% | 100.0% | 3-4 | 0.0% | 100.0% | 3-4 | 0.0% | 100.0% |
| 13 | Anti-MPO | 30 | Positive | C | 263.8 | 0.0% | 100.0% | 2 | 0.0% | 100.0% | 2-3 | 0.0% | 100.0% |
| 14 | Anti-MPO | 30 | Positive | C | 517.7 | 0.0% | 100.0% | 3-4 | 0.0% | 100.0% | 3-4 | 0.0% | 100.0% |
| 15 | Anti-PR3 | 30 | Positive | C | 1095.0 | 0.0% | 100.0% | 4 | 0.0% | 100.0% | 4 | 0.0% | 100.0% |
| 16 | N/A | 30 | Negative | - | 2.0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% | 0 | 100.0% | 0.0% |
| New samples (close to cut-off) | |||||||||||||
| 17 | Anti-MPO | 30 | Positive | C | 28.8 | 80.0% | 20.0% | 1-2 | 0.0% | 100.0% | 0-1 | 16.7% | 83.3% |
| 18 | Anti-MPO | 30 | Positive | C | 32.5 | 43.3% | 56.7% | 1-2 | 0.0% | 100.0% | 0-1 | 3.3% | 96.7% |
| 19 | Anti-PR3 | 30 | Positive | C | 16.8 | 90.0% | 10.0% | 1-2 | 0.0% | 100.0% | 0-1 | 56.7% | 43.3% |
| 20 | Anti-MPO | 30 | Positive | C | 36.7 | 30.0% | 70.0% | 1-2 | 0.0% | 100.0% | 1 | 0.0% | 100.0% |
| 21 | Anti-MPO | 30 | Positive | C | 22.9 | 76.7% | 23.3% | 1 | 0.00% | 100.0% | 0-1 | 13.3% | 86.7% |
| 22 | Anti-MPO | 30 | Positive | C | 24.3 | 86.7% | 13.3% | 1-2 | 0.0% | 100.0% | 0-1 | 3.3% | 96.7% |
| 23 | Anti-PR3 | 30 | Positive | C | 26.9 | 70.0% | 30.0% | 1-2 | 0.0% | 100.0% | 0-1 | 13.3% | 86.7% |
| 24 | Anti-PR3 | 30 | Positive | C | 20.3 | 86.7% | 13.3% | 1 | 0.0% | 100.0% | 0-1 | 16.7% | 83.3% |
| 25 | Anti-PR3 | 30 | Positive | C | 34.0 | 50.0% | 50.0% | 1-2 | 0.0% | 100.0% | 0-1 | 10.0% | 90.0% |
| 26 | Anti-PR3 | 30 | Positive | C | 35.7 | 56.7% | 63.3% | 1-2 | 0.00% | 100.0% | 0-1 | 3.3% | 96.7% |
ANCA Formalin repeatability and reproducibility
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| Expected Result | Within run | Between run | Between day | Total (within lab) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sample | Specificity | n | Average | ||||||||||
| Neg/Pos | Pattern | LIU | SD | %CV | SD | %CV | SD | %CV | SD | %CV | |||
| 1 | Anti-MPO | 30 | Positive | C | 788.8 | 64.4 | 8.2% | 66.3 | 8.4% | 59.6 | 7.6% | 110.0 | 13.9% |
| 2 | Anti-MPO | 30 | Positive | C | 218.7 | 37.7 | 17.2% | 14.5 | 6.6% | 5.8 | 2.6% | 40.8 | 18.7% |
| 3 | Anti-MPO | 30 | Positive | C | 127.4 | 29.4 | 23.1% | 11.4 | 9.0% | 8.3 | 6.5% | 32.6 | 25.6% |
| 4 | Anti-MPO | 30 | Borderline | C/- | 17.4 | 9.7 | 56.1% | 0.0 | 0.0% | 4.1 | 23.8% | 10.6 | 61.0% |
| 5 | N/A | 30 | Negative | - | 2.0 | 0.0 | 0.0% | 0.0 | 0.0% | 0.0 | 0.0% | 0.0 | 0.0% |
| 6 | Anti-PR3 | 30 | Positive | C | 1104.9 | 170.5 | 15.4% | 0.0 | 0.0% | 71.7 | 6.5% | 185.0 | 16.7% |
| 7 | Anti-PR3 | 30 | Positive | C | 491.2 | 43.4 | 8.8% | 8.1 | 1.7% | 42.7 | 8.7% | 61.5 | 12.5% |
| 8 | Anti-PR3 | 30 | Positive | C | 131.4 | 26.6 | 20.3% | 0.0 | 0.0% | 13.8 | 10.5% | 30.0 | 22.8% |
| 9 | Anti-PR3 | 30 | Positive | C | 128.5 | 20.1 | 15.7% | 29.7 | 23.1% | 0.0 | 0.0% | 35.9 | 27.9% |
| 10 | N/A | 30 | Negative | - | 2.8 | 1.4 | 51.1% | 0.0 | 0.0% | 0.6 | 20.5% | 1.6 | 55.1% |
| 11 | N/A | 30 | Negative | - | 2.0 | 0.2 | 9.0% | 0.1 | 2.6% | 0.0 | 0.0% | 0.2 | 9.3% |
| 12 | Anti-MPO | 30 | Positive | C | 406.7 | 48.5 | 11.9% | 10.4 | 2.6% | 50.9 | 12.5% | 71.1 | 17.5% |
| 13 | Anti-MPO | 30 | Positive | C | 242.9 | 38.4 | 15.8% | 7.0 | 2.9% | 20.0 | 8.2% | 43.8 | 18.0% |
| 14 | Anti-MPO | 30 | Positive | C | 517.7 | 69.0 | 13.3% | 28.9 | 5.6% | 0.0 | 0.0% | 74.8 | 14.4% |
| 15 | Anti-PR3 | 30 | Positive | C | 1095.0 | 187.2 | 17.1% | 0.0 | 0.0% | 44.4 | 4.1% | 192.4 | 17.6% |
| 16 | N/A | 30 | Negative | - | 2.0 | 0.0 | 0.0% | 0.0 | 0.0% | 0.0 | 0.0% | 0.0 | 0.0% |
| New samples (close to cut-off) | |||||||||||||
| 17 | Anti-MPO | 30 | Positive | C | 28.8 | 7.8 | 27.2% | 23.3 | 81.0% | 0.0 | 0.0% | 24.6 | 85.5% |
| 18 | Anti-MPO | 30 | Positive | C | 32.5 | 7.5 | 23.2% | 9.0 | 27.7% | 0.0 | 0.0% | 11.7 | 36.1% |
| 19 | Anti-PR3 | 30 | Positive | C | 16.8 | 8.3 | 49.7% | 4.3 | 25.6% | 0.0 | 0.0% | 9.4 | 55.9% |
| 20 | Anti-MPO | 30 | Positive | C | 36.7 | 6.8 | 18.4% | 7.2 | 19.6% | 0.0 | 0.0% | 9.9 | 26.9% |
| 21 | Anti-MPO | 30 | Positive | C | 22.9 | 5.5 | 23.8% | 5.6 | 24.4% | 0.6 | 2.4% | 7.8 | 34.2% |
| 22 | Anti-MPO | 30 | Positive | C | 24.3 | 11.3 | 46.5% | 6.7 | 27.5% | 0.0 | 0.0% | 13.1 | 54.0% |
| 23 | Anti-PR3 | 30 | Positive | C | 26.9 | 13.0 | 48.5% | 0.0 | 0.0% | 0.0 | 0.0% | 13.0 | 48.5% |
| 24 | Anti-PR3 | 30 | Positive | C | 20.3 | 7.7 | 38.1% | 0.0 | 0.0% | 5.8 | 28.6% | 9.7 | 47.6% |
| 25 | Anti-PR3 | 30 | Positive | C | 34.0 | 17.1 | 50.4% | 8.0 | 23.6% | 0.0 | 0.0% | 18.9 | 55.7% |
| 26 | Anti-PR3 | 30 | Positive | C | 35.7 | 13.2 | 37.0% | 14.1 | 39.4% | 0.0 | 0.0% | 19.3 | 54.1% |
NOTE: NOVA View DAPI ANCA are qualitative assays and have to be confirmed by the user
14.2.2 Between lots reproducibility
Lot to lot comparison study was performed on three reagent lots. Thirty-three clinically and/or analytically characterized samples were tested.
The following comparisons were made:
- NOVA view output: qualitative agreement and pattern agreement. ●
- Digital image reading: qualitative agreement, grade and pattern agreement .
- . Manual image reading: qualitative agreement, grade and pattern agreement comparison.
Acceptance criteria:
{16}------------------------------------------------
- . Qualitative agreement: ≥ 90%
- . Grade agreement: ≥ 90% within ± 1 reactivity grade
- Pattern agreement: ≥ 90% for digital and manual reading ●
Qualitative Agreement, Ethanol ANCA:
Qualitative agreement in three-way comparisons ranged from 97.0% to 100.0%.
NOVA View Summary Table
| NOVA View | Negative agreement (%)(95% CI) | Positive agreement (%)(95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| Lot 017103 vs lot 018119 | 100.0 (61.0 - 100.0) | 96.3 (81.7 - 99.3) | 97.0 (84.7 - 99.5) |
| Lot 017103 vs lot 022657 | 100.0 (61.0 - 100.0) | 96.3 (81.7 - 99.3) | 97.0 (84.7 - 99.5) |
| Lot 018119 vs lot 022657 | 100.0 (64.6 - 100.0) | 100.0 (87.1 -100.0) | 100.0 (89.6 -100.0) |
Manual Summary Table
| Manual | Negative agreement (%)(95% CI) | Positive agreement (%)(95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| Lot 017103 vs lot 018119 | 100.0 (61.0 - 100.0) | 100.0 (87.5 - 100.0) | 100.0 (89.6 - 100.0) |
| Lot 017103 vs lot 022657 | 100.0 (61.0 - 100.0) | 100.0 (87.7 - 100.0) | 100.0 (89.6 - 100.0) |
| Lot 018119 vs lot 022657 | 100.0 (61.0 - 100.0) | 100.0 (87.5 - 100.0) | 100.0 (89.6 - 100.0) |
Digital Summary Table
| Digital | Negative agreement (%)(95% CI) | Positive agreement (%)(95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| Lot 017103 vs lot 018119 | 100.0 (61.0 - 100.0) | 100.0 (87.5 - 100.0) | 100.0 (89.6 - 100.0) |
| Lot 017103 vs lot 022657 | 100.0 (61.0 - 100.0) | 100.0 (87.5 - 100.0) | 100.0 (89.6 - 100.0) |
| Lot 018119 vs lot 022657 | 100.0 (61.0 - 100.0) | 100.0 (87.5 - 100.0) | 100.0 (89.6 - 100.0) |
Qualitative Agreement, Formalin ANCA:
Total qualitative agreement in three-way comparisons ranged from 90.9% to 100.0%
NOVA View Summary Table
| Negative agreement (%)(95% CI) | Positive agreement (%)(95% CI) | Total agreement (%)(95% CI) | |
|---|---|---|---|
| NOVA View | |||
| Lot 018714 vs Lot 024112 | 100.0 (74.1 - 100.0) | 95.5 (78.2 - 99.2) | 97.0 (84.7 - 99.5) |
| Lot 018714 vs Lot RP0002 | 81.8 (52.3 - 94.9) | 95.5 (78.2 - 99.2) | 90.9 (76.4 - 96.9) |
| Lot 024112 vs Lot RP0002 | 83.3 (55.2 - 95.3) | 100.0 (84.5 - 100.0) | 93.9 (80.4 - 98.3) |
Manual Summary Table
| Manual | Negative agreement (%)(95% CI) | Positive agreement (%)(95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| Lot 018714 vs Lot 024112 | 100.0 (64.6 - 100.0) | 100.0 (87.1 - 100.0) | 100.0 (89.6 - 100.0) |
| Lot 018714 vs Lot RP0002 | 100.0 (64.6 - 100.0) | 100.0 (87.1 - 100.0) | 100.0 (89.6 - 100.0) |
| Lot 024112 vs Lot RP0002 | 100.0 (87.1 - 100.0) | 100.0 (87.1 - 100.0) | 100.0 (89.6 - 100.0) |
{17}------------------------------------------------
Digital Summary Table
| Digital | Negative agreement (%)(95% CI) | Positive agreement (%)(95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| Lot 018714 vs Lot 024112 | 100.0 (70.1 - 100.0) | 100.0 (86.2 - 100.0) | 100.0 (89.6 - 100.0) |
| Lot 018714 vs Lot RP0002 | 77.8 (45.3 - 93.7) | 95.8 (79.8 - 99.3) | 90.9 (76.4 - 96.9) |
| Lot 024112 vs Lot RP0002 | 77.8 (45.3 - 93.7) | 95.8 (79.8 - 99.3) | 90.9 (76.4 - 96.9) |
Grade agreement, Ethanol ANCA:
All grades (100%) were within ± 1 grade from each other for all samples in any pair-wise comparisons for both manual and digital reading.
| Manual grade comparison: | Digital grade comparison: | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Lot 018119 | Lot 018119 | ||||||||||||||
| Lot 17103 | 0 | 1 | 2 | 3 | 4 | Total | Lot 017103 | 0 | 1 | 2 | 3 | 4 | Total | ||
| 0 | 6 | 0 | 0 | 0 | 0 | 6 | 0 | 6 | 0 | 0 | 0 | 0 | 6 | ||
| 1 | 0 | 3 | 1 | 0 | 0 | 4 | 1 | 0 | 3 | 0 | 0 | 0 | 3 | ||
| 2 | 0 | 0 | 8 | 0 | 0 | 8 | 2 | 0 | 2 | 5 | 0 | 0 | 7 | ||
| 3 | 0 | 0 | 1 | 6 | 1 | 8 | 3 | 0 | 0 | 3 | 3 | 0 | 6 | ||
| 4 | 0 | 0 | 0 | 0 | 7 | 7 | 4 | 0 | 0 | 0 | 1 | 10 | 11 | ||
| Total | 6 | 3 | 10 | 6 | 8 | 33 | Total | 6 | 5 | 8 | 4 | 10 | 33 | ||
| within± one grade: | 100% | within± one grade: | 100% | ||||||||||||
| Lot 022657 | Lot 022657 | ||||||||||||||
| Lot 017103 | 0 | 1 | 2 | 3 | 4 | Total | Lot 017103 | 0 | 1 | 2 | 3 | 4 | Total | ||
| 0 | 6 | 0 | 0 | 0 | 0 | 6 | 0 | 6 | 0 | 0 | 0 | 0 | 6 | ||
| 1 | 0 | 4 | 0 | 0 | 0 | 4 | 1 | 0 | 3 | 0 | 0 | 0 | 3 | ||
| 2 | 0 | 0 | 7 | 1 | 0 | 8 | 2 | 0 | 2 | 5 | 0 | 0 | 7 | ||
| 3 | 0 | 0 | 1 | 5 | 2 | 8 | 3 | 0 | 0 | 2 | 4 | 0 | 6 | ||
| 4 | 0 | 0 | 0 | 0 | 7 | 7 | 4 | 0 | 0 | 0 | 0 | 11 | 11 | ||
| Total | 6 | 4 | 8 | 6 | 9 | 33 | Total | 6 | 5 | 7 | 4 | 11 | 33 | ||
| within± one grade: | 100% | within± one grade: | 100% | ||||||||||||
| Lot 022657 | Lot 022657 | ||||||||||||||
| Lot 18119 | 0 | 1 | 2 | 3 | 4 | Total | Lot 018119 | 0 | 1 | 2 | 3 | 4 | Total | ||
| 0 | 6 | 0 | 0 | 0 | 0 | 6 | 0 | 6 | 0 | 0 | 0 | 0 | 6 | ||
| 1 | 0 | 3 | 0 | 0 | 0 | 3 | 1 | 0 | 5 | 0 | 0 | 0 | 5 | ||
| 2 | 0 | 1 | 8 | 1 | 0 | 10 | 2 | 0 | 0 | 6 | 2 | 0 | 8 | ||
| 3 | 0 | 0 | 0 | 5 | 1 | 6 | 3 | 0 | 0 | 1 | 2 | 1 | 4 | ||
| 4 | 0 | 0 | 0 | 0 | 8 | 8 | 4 | 0 | 0 | 0 | 0 | 10 | 10 | ||
| Total | 6 | 4 | 8 | 6 | 9 | 33 | Total | 6 | 5 | 7 | 4 | 11 | 33 | ||
| within± one grade: | 100% | within± one grade: | 100% |
Grade agreement, Formalin ANCA:
All grades (100%) were within ± 1 grade from each other for all samples in any pair-wise comparisons for both manual and digital reading.
{18}------------------------------------------------
Manual grade comparison:
| Lot 024112 | ||||||
|---|---|---|---|---|---|---|
| Lot 018714 | 0 | 1 | 2 | 3 | 4 | Total |
| 0 | 7 | 0 | 0 | 0 | 0 | 7 |
| 1 | 0 | 4 | 0 | 0 | 0 | 4 |
| 2 | 0 | 1 | 8 | 2 | 0 | 11 |
| 3 | 0 | 0 | 0 | 4 | 2 | 6 |
| 4 | 0 | 0 | 0 | 0 | 5 | 5 |
| Total | 7 | 5 | 8 | 6 | 7 | 33 |
| within± one grade: | 100% | |||||
| Lot RP0002 | ||||||
| Lot 018714 | 0 | 1 | 2 | 3 | 4 | Total |
| 0 | 7 | 0 | 0 | 0 | 0 | 7 |
| 1 | 0 | 3 | 1 | 0 | 0 | 4 |
| 2 | 0 | 1 | 6 | 4 | 0 | 11 |
| 3 | 0 | 0 | 1 | 3 | 2 | 6 |
| 4 | 0 | 0 | 0 | 0 | 5 | 5 |
| Total | 7 | 4 | 8 | 7 | 7 | 33 |
Digital grade comparison:
| Lot 024112 | ||||||
|---|---|---|---|---|---|---|
| Lot 018714 | 0 | 1 | 2 | 3 | 4 | Total |
| 0 | 9 | 0 | 0 | 0 | 0 | 9 |
| 1 | 0 | 4 | 2 | 0 | 0 | 6 |
| 2 | 0 | 1 | 3 | 5 | 0 | 9 |
| 3 | 0 | 0 | 0 | 1 | 1 | 2 |
| 4 | 0 | 0 | 0 | 2 | 5 | 7 |
| Total | 9 | 5 | 5 | 8 | 6 | 33 |
| within± one grade: | 100% | |||||
| Lot RP0002 | ||||||
| Lot 018714 | 0 | 1 | 2 | 3 | 4 | Total |
| 0 | 7 | 2 | 0 | 0 | 0 | 9 |
| 1 | 1 | 3 | 2 | 0 | 0 | 6 |
| 2 | 0 | 0 | 5 | 4 | 0 | 9 |
| 3 | 0 | 0 | 1 | 1 | 0 | 2 |
| 4 | 0 | 0 | 0 | 0 | 7 | 7 |
| Total | 8 | 5 | 8 | 5 | 7 | 33 |
within± one grade:
100% within± one grade: 100% Lot RP0002 Lot RP0002 Lot 024112 Lot 024112 దు Total చ Total O O O O O ნ లు దు O దు రా ను O O Total Total within± one grade: 100% within± one grade: 100%
{19}------------------------------------------------
Pattern agreement, Ethanol ANCA:
Pattern agreement was 100% for both manual and digital reading. Pattern agreement for NOVA View software interpretation ranged from 71.9% to 75.8%. This agreement value includes positive/negative discrepancies, as well as discrepancy originating from NOVA View reporting Unrecognized pattern.
| NOVA View pattern agreement | Manual pattern agreement | Digital pattern agreement | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Lot 018119 | Lot 018119 | Lot 018119 | |||||||||||||
| Lot 017103 | Neg | C | P | U | Total | Lot 017103 | Neg | C | P | Total | Lot 017103 | Neg | C | P | Total |
| Neg | 6 | 0 | 0 | 0 | 6 | Neg | 6 | 0 | 0 | 6 | Neg | 6 | 0 | 0 | 6 |
| C | 1 | 2 | 0 | 6 | 9 | C | 0 | 13 | 0 | 13 | C | 0 | 13 | 0 | 13 |
| P | 0 | 0 | 12 | 0 | 12 | P | 0 | 0 | 14 | 14 | P | 0 | 0 | 14 | 14 |
| U | 0 | 0 | 1 | 4 | 5 | Total | 6 | 13 | 14 | 33 | Total | 6 | 13 | 14 | 33 |
| Total | 7 | 2 | 13 | 10 | 32 | agreement: 100.0% | agreement: 100.0% | ||||||||
| agreement: 75.0% | |||||||||||||||
| Lot 022657 | Lot 022657 | Lot 022657 | |||||||||||||
| Lot 017103 | Neg | C | P | U | Total | Lot 017103 | Neg | C | P | Total | Lot 017103 | Neg | C | P | Total |
| Neg | 6 | 0 | 0 | 0 | 6 | Neg | 6 | 0 | 0 | 6 | Neg | 6 | 0 | 0 | 6 |
| C | 1 | 5 | 0 | 3 | 9 | C | 0 | 13 | 0 | 13 | C | 0 | 13 | 0 | 13 |
| P | 0 | 0 | 12 | 1 | 13 | P | 0 | 0 | 14 | 14 | P | 0 | 0 | 14 | 14 |
| U | 0 | 2 | 1 | 2 | 5 | Total | 6 | 13 | 14 | 33 | Total | 6 | 13 | 14 | 33 |
| Total | 7 | 7 | 13 | 6 | 33 | agreement: 100.0% | agreement: 100.0% | ||||||||
| agreement: 75.8% | |||||||||||||||
| Lot 022657 | Lot 022657 | Lot 022657 | |||||||||||||
| Lot 018119 | Neg | C | P | U | Total | Lot 018119 | Neg | C | P | Total | Lot 018119 | Neg | C | P | Total |
| Neg | 7 | 0 | 0 | 0 | 7 | Neg | 6 | 0 | 0 | 6 | Neg | 6 | 0 | 0 | 6 |
| C | 0 | 1 | 0 | 1 | 2 | C | 0 | 13 | 0 | 13 | C | 0 | 13 | 0 | 13 |
| P | 0 | 1 | 11 | 1 | 13 | P | 0 | 0 | 14 | 14 | P | 0 | 0 | 14 | 14 |
| U | 0 | 5 | 1 | 4 | 10 | Total | 6 | 13 | 14 | 33 | Total | 6 | 13 | 14 | 33 |
| Total | 7 | 7 | 12 | 6 | 32 | agreement: 100.0% | agreement: 100.0% | ||||||||
| agreement: 71.9% |
{20}------------------------------------------------
Pattern agreement, Formalin ANCA:
Pattern agreement ranged from 90.9% to 100% for both manual and digital reading. Pattern agreement for NOVA View software interpretation ranged from 81.8% to 87.9%. This agreement value includes positive/negative discrepancies, as well as discrepancy originating from NOVA View reporting Unrecognized pattern.
| Lot 024112 | Lot 024112 | Lot 024112 | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Lot 018714 | Neg | C | U | Total | Lot 018714 | Neg | C | N | Total | Lot 018714 | Neg | C | N | Total |
| Neg | 11 | 0 | 0 | 11 | Neg | 7 | 0 | 0 | 7 | Neg | 9 | 0 | 0 | 9 |
| C | 0 | 16 | 1 | 17 | C | 0 | 25 | 0 | 25 | C | 0 | 24 | 0 | 24 |
| U | 1 | 2 | 2 | 5 | N | 0 | 0 | 1 | 1 | N | 0 | 0 | 0 | 0 |
| Total | 12 | 18 | 3 | 33 | Total | 7 | 25 | 1 | 33 | Total | 9 | 24 | 0 | 33 |
| agreement: | 87.9% | agreement: | 100% | agreement: | 100% | |||||||||
| Lot RP0002 | Lot RP0002 | Lot RP0002 | ||||||||||||
| Lot 018714 | Neg | C | U | Total | Lot 018714 | Neg | C | N | Total | Lot 018714 | Neg | C | N | Total |
| Neg | 9 | 0 | 2 | 11 | Neg | 7 | 0 | 0 | 7 | Neg | 7 | 0 | 2 | 9 |
| C | 0 | 17 | 0 | 17 | C | 0 | 25 | 0 | 25 | C | 1 | 23 | 0 | 24 |
| U | 1 | 3 | 1 | 5 | N | 0 | 0 | 1 | 1 | N | 0 | 0 | 0 | 0 |
| Total | 10 | 20 | 3 | 33 | Total | 7 | 25 | 1 | 33 | Total | 8 | 23 | 2 | 33 |
| agreement: | 81.8% | agreement: | 100% | agreement: | 90.9% | |||||||||
| Lot RP0002 | Lot RP0002 | Lot RP0002 | ||||||||||||
| Lot 024112 | Neg | C | U | Total | Lot 024112 | Neg | C | N | Total | Lot 024112 | Neg | C | N | Total |
| Neg | 10 | 0 | 2 | 12 | Neg | 7 | 0 | 0 | 7 | Neg | 7 | 0 | 2 | 9 |
| C | 0 | 18 | 0 | 18 | C | 0 | 25 | 0 | 25 | C | 1 | 23 | 0 | 24 |
| U | 0 | 2 | 1 | 3 | N | 0 | 0 | 1 | 1 | N | 0 | 0 | 0 | 0 |
| Total | 10 | 20 | 3 | 33 | Total | 7 | 25 | 1 | 33 | Total | 8 | 23 | 2 | 33 |
| agreement: | 87.9% | agreement: | 100% | agreement: | 90.9% |
14.2.3 Between sites/instruments reproducibility
The same 287 clinically characterized samples were tested with both Ethanol ANCA and Formalin ANCA at three testing sites, using three different NOVA View instruments: in Inova's laboratory, and two external US clinical laboratories. The two external sites each also tested 100 routine clinical samples that ANCA testing was requested from. The composition of the sample cohorts and the results obtained by the three sites are shown below:
{21}------------------------------------------------
Site #1 (Inova)
Ethanol ANCA
| Diagnosis | N | NOVA View pos | Manual pos | Digital pos | |||
|---|---|---|---|---|---|---|---|
| # | % | # | % | # | % | ||
| ANCA Associated Vasculitis (AAV) | 80 | 68 | 85% | 71 | 89% | 70 | 88% |
| Characterized MPO/PR3 | 49 | 47 | 96% | 49 | 100% | 49 | 100% |
| Infectious Disease | 20 | 4 | 20% | 11 | 55% | 8 | 40% |
| Chronic Kidney Disease (CKD) | 18 | 9 | 50% | 13 | 72% | 10 | 56% |
| Dermatitis | 12 | 3 | 25% | 4 | 33% | 3 | 25% |
| Diabetes Type II | 20 | 8 | 40% | 8 | 40% | 8 | 40% |
| Celiac (tTG IgA POS) | 20 | 3 | 15% | 4 | 20% | 4 | 20% |
| Chronic Obstructive Pulmonary Disease (COPD) | 20 | 8 | 40% | 9 | 45% | 9 | 45% |
| Rheumatoid Arthritis (RA) | 15 | 12 | 80% | 12 | 80% | 12 | 80% |
| Crohn's Disease | 11 | 6 | 55% | 6 | 55% | 6 | 55% |
| Ulcerative Colitis | 15 | 4 | 27% | 8 | 53% | 5 | 33% |
| Allergy | 7 | 2 | 29% | 3 | 43% | 2 | 29% |
| Total | 287 |
Formalin ANCA
| Diagnosis | N | NOVA View pos | Manual pos | Digital pos | |||
|---|---|---|---|---|---|---|---|
| # | % | # | % | # | % | ||
| ANCA Associated Vasculitis (AAV) | 80 | 66 | 83% | 74 | 93% | 71 | 89% |
| Characterized MPO/PR3 | 49 | 46 | 94% | 49 | 100% | 48 | 98% |
| Infectious Disease | 20 | 0 | 0% | 3 | 15% | 0 | 0% |
| Chronic Kidney Disease (CKD) | 18 | 0 | 0% | 1 | 6% | 1 | 6% |
| Dermatitis | 12 | 0 | 0% | 0 | 0% | 0 | 0% |
| Diabetes Type II | 20 | 0 | 0% | 0 | 0% | 1 | 5% |
| Celiac (tTG IgA POS) | 20 | 0 | 0% | 1 | 5% | 1 | 5% |
| Chronic Obstructive Pulmonary Disease (COPD) | 20 | 0 | 0% | 2 | 10% | 2 | 10% |
| Rheumatoid Arthritis (RA) | 15 | 2 | 13% | 3 | 20% | 2 | 13% |
| Crohn's Disease | 11 | 3 | 27% | 2 | 18% | 2 | 18% |
| Ulcerative Colitis | 15 | 0 | 0% | 2 | 13% | 1 | 7% |
| Allergy | 7 | 0 | 0% | 1 | 14% | 2 | 29% |
| Total | 287 |
{22}------------------------------------------------
Site #2
Ethanol ANCA
| Diagnosis | N | NOVA View pos | Manual pos | Digital pos | |||
|---|---|---|---|---|---|---|---|
| # | % | # | % | # | % | ||
| ANCA Associated Vasculitis (AAV) | 80 | 56 | 70% | 60 | 75% | 57 | 71% |
| Characterized MPO/PR3 | 49 | 46 | 94% | 45 | 92% | 46 | 94% |
| Infectious Disease | 16* | 2 | 13% | 7 | 44% | 3 | 19% |
| Chronic Kidney Disease (CKD) | 18 | 8 | 44% | 9 | 50% | 8 | 44% |
| Dermatitis | 12 | 3 | 25% | 4 | 33% | 3 | 25% |
| Diabetes Type II | 20 | 3 | 15% | 6 | 30% | 4 | 20% |
| Celiac (tTG IgA POS) | 20 | 2 | 10% | 3 | 15% | 2 | 10% |
| Chronic Obstructive Pulmonary Disease (COPD) | 20 | 5 | 25% | 7 | 35% | 7 | 35% |
| Rheumatoid Arthritis (RA) | 15 | 12 | 80% | 13 | 87% | 12 | 80% |
| Crohn's Disease | 11 | 6 | 55% | 6 | 55% | 6 | 55% |
| Ulcerative Colitis | 15 | 4 | 27% | 7 | 47% | 5 | 33% |
| Allergy | 7 | 2 | 29% | 2 | 29% | 2 | 29% |
| Routine ANCA samples | 100 | 46 | 46% | 56 | 56% | 49 | 49% |
| Total | 383* |
*4 samples were not tested due to sample depletion.
Formalin ANCA
| Diagnosis | N | NOVA View pos | Manual pos | Digital pos | |||
|---|---|---|---|---|---|---|---|
| # | % | # | % | # | % | ||
| ANCA Associated Vasculitis (AAV) | 80 | 61 | 76% | 64 | 80% | 65 | 81% |
| Characterized MPO/PR3 | 49 | 45 | 92% | 46 | 94% | 47 | 96% |
| Infectious Disease | 20 | 1 | 5% | 5 | 25% | 0 | 0% |
| Chronic Kidney Disease (CKD) | 18 | 2 | 11% | 1 | 6% | 2 | 11% |
| Dermatitis | 12 | 0 | 0% | 0 | 0% | 0 | 0% |
| Diabetes Type II | 20 | 0 | 0% | 1 | 5% | 1 | 5% |
| Celiac (tTG IgA POS) | 20 | 0 | 0% | 1 | 5% | 1 | 5% |
| Chronic Obstructive Pulmonary Disease (COPD) | 20 | 1 | 5% | 1 | 5% | 1 | 5% |
| Rheumatoid Arthritis (RA) | 15 | 1 | 7% | 1 | 7% | 1 | 7% |
| Crohn's Disease | 11 | 3 | 27% | 3 | 27% | 2 | 18% |
| Ulcerative Colitis | 15 | 0 | 0% | 1 | 7% | 0 | 0% |
| Allergy | 7 | 1 | 14% | 1 | 14% | 1 | 14% |
| Routine ANCA samples | 100 | 28 | 28% | 31 | 31% | 27 | 27% |
| Total | 387 |
{23}------------------------------------------------
Site #3
Ethanol ANCA
| Diagnosis | N | NOVA View pos | Manual pos | Digital pos | |||
|---|---|---|---|---|---|---|---|
| # | % | # | % | # | % | ||
| ANCA Associated Vasculitis (AAV) | 80 | 56 | 70% | 58 | 73% | 57 | 71% |
| Characterized MPO/PR3 | 49 | 46 | 94% | 46 | 94% | 47 | 96% |
| Infectious Disease | 20 | 5 | 25% | 4 | 20% | 6 | 30% |
| Chronic Kidney Disease (CKD) | 18 | 8 | 44% | 9 | 50% | 8 | 44% |
| Dermatitis | 12 | 3 | 25% | 4 | 33% | 3 | 25% |
| Diabetes Type II | 20 | 2 | 10% | 4 | 20% | 3 | 15% |
| Celiac (tTG IgA POS) | 20 | 2 | 10% | 3 | 15% | 2 | 10% |
| Chronic Obstructive Pulmonary Disease (COPD) | 20 | 6 | 30% | 7 | 35% | 7 | 35% |
| Rheumatoid Arthritis (RA) | 15 | 11 | 73% | 12 | 80% | 12 | 80% |
| Crohn's Disease | 11 | 6 | 55% | 6 | 55% | 6 | 55% |
| Ulcerative Colitis | 15 | 5 | 33% | 5 | 33% | 5 | 33% |
| Allergy | 7 | 2 | 29% | 3 | 43% | 2 | 29% |
| Routine ANCA samples | 100 | 31 | 31% | 37 | 37% | 37 | 37% |
| Total | 387 |
Formalin ANCA
| Diagnosis | N | NOVA View pos | Manual pos | Digital pos | |||
|---|---|---|---|---|---|---|---|
| # | % | # | % | # | % | ||
| ANCA Associated Vasculitis (AAV) | 80 | 60 | 75% | 62 | 78% | 61 | 76% |
| Characterized MPO/PR3 | 49 | 42 | 86% | 43 | 88% | 44 | 90% |
| Infectious Disease | 20 | 0 | 0% | 2 | 10% | 2 | 10% |
| Chronic Kidney Disease (CKD) | 18 | 0 | 0% | 0 | 0% | 0 | 0% |
| Dermatitis | 12 | 0 | 0% | 0 | 0% | 0 | 0% |
| Diabetes Type II | 20 | 0 | 0% | 1 | 5% | 1 | 5% |
| Celiac (tTG IgA POS) | 20 | 0 | 0% | 1 | 5% | 0 | 0% |
| Chronic Obstructive Pulmonary Disease (COPD) | 20 | 2 | 10% | 2 | 10% | 2 | 10% |
| Rheumatoid Arthritis (RA) | 15 | 1 | 7% | 2 | 13% | 1 | 7% |
| Crohn's Disease | 11 | 2 | 18% | 2 | 18% | 2 | 18% |
| Ulcerative Colitis | 15 | 0 | 0% | 0 | 0% | 0 | 0% |
| Allergy | 7 | 0 | 0% | 1 | 14% | 1 | 14% |
| Routine ANCA samples | 100 | 10 | 10% | 10 | 10% | 9 | 9% |
| Total | 387 |
{24}------------------------------------------------
Results obtained on the 287 samples that were tested by each site were compared. Qualitative agreement, pattern agreement and grade agreement were calculated according to NOVA View software interpretation, manual reading and digital image reading.
Acceptance criteria:
- Qualitative agreement: ≥ 85% .
- . Grade agreement: ≥ 90% within ± 1 reactivity grade
- . Pattern agreement: ≥ 80%, after excluding positive/negative discrepancies
Ethanol ANCA
Qualitative agreement:
| NOVA View,n=287 | Positive agreement (%)(95% CI) | Negative agreement (%)(95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| Site 1 vs Site 2 | 86.2 (80.3 - 90.6) | 98.2 (93.8 - 99.5) | 90.9 (87.1 - 93.7) |
| Site 1 vs Site 3 | 86.0 (80.1 - 90.4) | 99.1 (95.1 - 99.8) | 91.2 (87.3 - 93.9) |
| Site 2 vs Site 3 | 96.0 (91.5 - 98.2) | 96.2 (91.5 - 98.4) | 96.1 (93.2 - 97.8) |
| Positive agreement (%)(95% CI) | Negative agreement (%)(95% CI) | Total agreement (%)(95% CI) | |
|---|---|---|---|
| Manual, n=287 | 80.8 (74.8 - 85.7) | 98.9 (93.9 - 99.8) | 86.4 (82.0 - 89.9) |
| Site 1 vs Site 2 | 84.5 (78.8 - 88.9) | 94.4 (87.5 - 97.6) | 87.6 (83.3 - 91.0) |
| Site 1 vs Site 3 | 95.6 (91.2 - 97.9) | 86.3 (79.1 - 91.3) | 91.5 (87.7 - 94.2) |
| Site 2 vs Site 3 |
| Digital, n=287 | Positive agreement (%)(95% CI) | Negative agreement (%)(95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| Site 1 vs Site 2 | 85.5 (79.7 - 89.8) | 100 (96.3 - 100) | 90.6 (86.7 - 93.5) |
| Site 1 vs Site 3 | 84.7 (78.8 - 89.2) | 100 (96.3 - 100) | 90.1 (86.1 - 93.1) |
| Site 2 vs Site 3 | 96.2 (91.9 - 98.2) | 96.1 (91.1 - 98.3) | 96.1 (93.2 - 97.8) |
Grade agreement:
| Manual, n=287 | Within ± 1 grade |
|---|---|
| Site 1 vs Site 2 | 98.0% |
| Site 1 vs Site 3 | 96.0% |
| Site 2 vs Site 3 | 96.0% |
{25}------------------------------------------------
| Page | 23 of 45 |
|---|---|
| ------ | ---------- |
| Digital, n=287 | Within ± 1 grade |
|---|---|
| Site 1 vs Site 2 | 98.0% |
| Site 1 vs Site 3 | 97.0% |
| Site 2 vs Site 3 | 99.0% |
Pattern agreement:
| NOVA View, n=287 | Pattern agreement with pos/neg disagreement included | Pattern agreement without pos/neg disagreement excluded |
|---|---|---|
| Site 1 vs Site 2 | 84.0% | 94.0% |
| Site 1 vs Site 3 | 81.0% | 90.0% |
| Site 2 vs Site 3 | 90.0% | 94.0% |
| Pattern agreement with pos/neg disagreement included | Pattern agreement without pos/neg disagreement excluded | |
|---|---|---|
| Manual, n=287 | 84.0% | 98.0% |
| Site 1 vs Site 2 | 86.0% | 98.0% |
| Site 1 vs Site 3 | 92.0% | 100.0% |
| Site 2 vs Site 3 |
| Digital, n=287 | Pattern agreement with pos/negdisagreement included | Pattern agreement withoutpos/neg disagreement excluded |
|---|---|---|
| Site 1 vs Site 2 | 89.0% | 98.0% |
| Site 1 vs Site 3 | 89.0% | 98.0% |
| Site 2 vs Site 3 | 96.0% | 100.0% |
Formalin ANCA
Qualitative agreement:
| NOVA View,n=287 | Positive agreement (%)(95% CI) | Negative agreement (%)(95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| Site 1 vs Site 2 | 88.8 (81.8 - 93.3) | 97.1 (93.3 - 98.7) | 93.7 (90.3 - 96.0) |
| Site 1 vs Site 3 | 92.2 (85.9 - 95.9) | 95.3 (91.0 - 97.6) | 94.1 (90.7 - 96.3) |
| Site 2 vs Site 3 | 96.3 (90.9 - 98.6) | 93.9 (89.3 - 96.5) | 94.8 (91.6 - 96.8) |
| Manual, n=287 | Positive agreement (%) | Negative agreement (%) | Total agreement (%) |
|---|---|---|---|
| (95% CI) | (95% CI) | (95% CI) | |
| Site 1 vs Site 2 | 81.9 (74.6 - 87.4) | 98.0 (94.2 - 99.3) | 90.2 (86.3 - 93.2) |
| Site 1 vs Site 3 | 86.2 (79.5 - 91.0) | 96.0 (91.5 - 98.1) | 91.3 (87.5 - 94.0) |
| Site 2 vs Site 3 | 92.2 (85.9 - 95.9) | 89.5 (84.0 - 93.2) | 90.6 (86.7 - 93.5) |
{26}------------------------------------------------
| Digital, n=287 | Positive agreement (%) | Negative agreement (%) | Total agreement (%) |
|---|---|---|---|
| (95% CI) | (95% CI) | (95% CI) | |
| Site 1 vs Site 2 | 85.5 (78.5 - 90.5) | 98.7 (95.4 - 99.6) | 92.7 (89.1 - 95.2) |
| Site 1 vs Site 3 | 90.8 (84.7 - 94.7) | 98.7 (95.4 - 99.6) | 95.1 (92.0 - 97.1) |
| Site 2 vs Site 3 | 97.4 (92.5 - 99.1) | 94.2 (89.7 - 96.8) | 95.5 (92.4 - 97.3) |
Grade agreement:
| Manual, n=287 | Within ± 1 grade |
|---|---|
| Site 1 vs Site 2 | 98.0% |
| Site 1 vs Site 3 | 94.0% |
| Site 2 vs Site 3 | 91.0% |
| Digital, n=287 | Within ± 1 grade |
|---|---|
| Site 1 vs Site 2 | 99.0% |
| Site 1 vs Site 3 | 99.0% |
| Site 2 vs Site 3 | 98.0% |
Pattern agreement:
| NOVA View, n=287 | Pattern agreement with pos/neg disagreement included | Pattern agreement without pos/neg disagreement excluded |
|---|---|---|
| Site 1 vs Site 2 | 87.0% | 93.0% |
| Site 1 vs Site 3 | 88.0% | 93.0% |
| Site 2 vs Site 3 | 89.0% | 94.0% |
| Manual, n=287 | Pattern agreement with pos/neg disagreement included | Pattern agreement without pos/neg disagreement excluded |
|---|---|---|
| Site 1 vs Site 2 | 90.0% | 100.0% |
| Site 1 vs Site 3 | 90.0% | 98.0% |
| Site 2 vs Site 3 | 90.0% | 99.0% |
| Digital, n=287 | Pattern agreement with pos/neg disagreement included | Pattern agreement without pos/neg disagreement excluded | |
|---|---|---|---|
| Site 1 vs Site 2 | 92.0% | 100.0% | |
| Site 1 vs Site 3 | 94.0% | 99.0% | |
| Site 2 vs Site 3 | 94.0% | 99.0% |
{27}------------------------------------------------
14.2.4 Between operators reproducibility
Ten samples (2 negative, 4 P-ANCA and 4 C-ANCA positive) were tested at each site for 5 days in 5 replicates (25 data points per sample). Manual and digital reading was performed by two operators at each site, to assess between operators reproducibility.
Results are summarized below:
Ethanol ANCA, NOVA View Results
LIU:
| Expected result | NOVA View interpretation | |||||
|---|---|---|---|---|---|---|
| Sample | n | neg/pos | pattern | Site #1Mean LIU | Site #2Mean LIU | Site #3Mean LIU |
| NVA 0224 | 25 | pos | C | 508.2 | 475.6 | 405.6 |
| NVA 0232 | 25 | pos | C | 281.7 | 239.8 | 272.3 |
| NVA 0226 | 25 | pos | C | 156.4 | 115.5 | 177.0 |
| NVA 0225 | 25 | pos | C | 44.6 | 24.2 | 54.2 |
| NVA 0206 | 25 | pos | P | 1257.2 | 1432.6 | 1403.6 |
| NVA 0202 | 25 | pos | P | 589.3 | 664.3 | 673.7 |
| NVA 0210 | 25 | pos | P | 226.0 | 274.8 | 280.3 |
| NVA 0222 | 25 | pos | P | 163.5 | 125.5 | 155.7 |
| NVA 0289 | 25 | neg | n/a | 3.2 | 2.0 | 2.6 |
| NVA 0288 | 25 | neg | n/a | 3.1 | 2.1 | 2.7 |
Summary of SD and %CV:
| Sample | n | Expected result | Average | Within Day | Between days | Within site | Between Site | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| neg/pos | pattern | LIU | SD | %CV | SD | %CV | SD | %CV | SD | %CV | ||
| NVA 0224 | 25 | pos | C | 463.2 | 98.9 | 19.5% | 76.4 | 15.1% | 125.0 | 24.6% | 0.0 | 0.0% |
| NVA 0232 | 25 | pos | C | 264.6 | 38.8 | 14.7% | 34.7 | 13.1% | 52.1 | 19.7% | 13.5 | 5.1% |
| NVA 0226 | 25 | pos | C | 149.6 | 29.6 | 19.8% | 33.3 | 22.3% | 44.6 | 29.8% | 26.9 | 18.0% |
| NVA 0225 | 25 | pos | C | 41.0 | 9.2 | 22.5% | 12.3 | 30.0% | 15.4 | 37.5% | 14.2 | 34.6% |
| NVA 0206 | 25 | pos | P | 1364.4 | 133.4 | 9.8% | 135.7 | 9.9% | 190.3 | 13.9% | 66.7 | 4.9% |
| NVA 0202 | 25 | pos | P | 642.4 | 88.8 | 13.8% | 80.7 | 12.6% | 120.0 | 18.7% | 22.9 | 3.6% |
| NVA 0210 | 25 | pos | P | 260.4 | 36.1 | 13.9% | 21.2 | 8.1% | 41.9 | 16.1% | 27.4 | 10.5% |
| NVA 0222 | 25 | pos | P | 148.2 | 31.7 | 21.4% | 30.4 | 20.5% | 43.9 | 29.6% | 13.4 | 9.0% |
| NVA 0289 | 25 | neg | n/a | 2.6 | 0.9 | 36.9% | 0.6 | 22.8% | 1.1 | 43.4% | 0.5 | 18.7% |
| NVA 0288 | 25 | neg | n/a | 2.6 | 1.2 | 44.3% | 0.7 | 25.5% | 1.3 | 51.1% | 0.3 | 11.4% |
{28}------------------------------------------------
Ethanol ANCA, manual reading Qualitative agreement:
| Expected result | Manual reading | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Site #1 | Site #2 | Site #3 | |||||||||||||
| Reader #1 | Reader #2 | Reader #1 | Reader #2 | Reader #1 | Reader #2 | ||||||||||
| Sample | n | neg/pos | pattern | % neg | % pos | % neg | % pos | % neg | % pos | % neg | % pos | % neg | % pos | % neg | % pos |
| 1 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 2 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 3 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 4 | 25 | pos | C | 0% | 100% | 0% | 100% | 56% | 44% | 0% | 100% | 0% | 100% | 0% | 100% |
| 5 | 25 | pos | P | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 6 | 25 | pos | P | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 7 | 25 | pos | P | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 8 | 25 | pos | P | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 9 | 25 | neg | n/a | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% |
| 10 | 25 | neg | n/a | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% |
Grade agreement:
| Sample | n | neg/pos | pattern | Site #1 | Site #2 | Site #3 | |||
|---|---|---|---|---|---|---|---|---|---|
| Reader #1 | Reader #2 | Reader #1 | Reader #2 | Reader #1 | Reader #2 | ||||
| 1 | 25 | pos | C | 3.4 | 3.0 | 2.8 | 3.4 | 3.9 | 3.0 |
| 2 | 25 | pos | C | 2.9 | 2.0 | 1.7 | 2.3 | 2.0 | 1.7 |
| 3 | 25 | pos | C | 1.9 | 1.4 | 1.2 | 1.6 | 1.5 | 1.1 |
| 4 | 25 | pos | C | 1.0 | 1.0 | 0.4 | 1.0 | 1.0 | 1.0 |
| 5 | 25 | pos | P | 4.0 | 4.0 | 4.0 | 4.0 | 4.0 | 3.8 |
| 6 | 25 | pos | P | 3.0 | 3.1 | 3.2 | 3.2 | 3.1 | 2.2 |
| 7 | 25 | pos | P | 1.9 | 1.8 | 2.0 | 2.0 | 2.0 | 1.6 |
| 8 | 25 | pos | P | 1.6 | 2.0 | 1.0 | 1.7 | 2.0 | 1.2 |
| 9 | 25 | neg | n/a | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| 10 | 25 | neg | n/a | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
{29}------------------------------------------------
Ethanol ANCA, digital reading Qualitative agreement:
| Expected result | Digital reading | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Sample | n | neg/pos | pattern | Site #1 | Site #2 | Site #3 | |||||
| Reader #1 | Reader #2 | Reader #1 | Reader #2 | Reader #1 | Reader #2 | ||||||
| % neg | % pos | % neg | % pos | % neg | % pos | % neg | % pos | ||||
| 1 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 2 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 3 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 4 | 25 | pos | C | 0% | 100% | 0% | 100% | 8% | 92% | 4% | 96% |
| 5 | 25 | pos | P | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 6 | 25 | pos | P | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 7 | 25 | pos | P | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 8 | 25 | pos | P | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 9 | 25 | neg | n/a | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% |
| 10 | 25 | neg | n/a | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% |
Grade agreement:
| Sample | n | neg/pos | pattern | Site #1 | Site #2 | Site #3 | |||
|---|---|---|---|---|---|---|---|---|---|
| Reader #1 | Reader #2 | Reader #1 | Reader #2 | Reader #1 | Reader #2 | ||||
| 1 | 25 | pos | C | 3.6 | 3.5 | 3.2 | 4.0 | 4.0 | 3.3 |
| 2 | 25 | pos | C | 3.0 | 2.6 | 2.0 | 2.2 | 2.6 | 1.5 |
| 3 | 25 | pos | C | 2.0 | 2.0 | 1.4 | 1.8 | 2.1 | 1.2 |
| 4 | 25 | pos | C | 1.0 | 1.0 | 0.9 | 1.0 | 1.0 | 0.7 |
| 5 | 25 | pos | P | 4.0 | 4.0 | 4.0 | 4.0 | 4.0 | 4.0 |
| 6 | 25 | pos | P | 3.6 | 4.0 | 3.6 | 3.4 | 4.0 | 3.5 |
| 7 | 25 | pos | P | 1.9 | 2.0 | 2.0 | 2.1 | 2.0 | 1.7 |
| 8 | 25 | pos | P | 1.7 | 1.8 | 1.1 | 1.2 | 1.3 | 1.0 |
| 9 | 25 | neg | n/a | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| 10 | 25 | neg | n/a | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
Ethanol ANCA
Agreement between Operator 1 and Operator 2 at each site:
| % Overall Agreement (Positive/Negative) between operators (per site) for Ethanol | |||
|---|---|---|---|
| Inova | Site #2 | Site #3 | |
| Manual Reading | 100.0% | 100.0% | 94.4% |
| Digital Image Reading | 100.0% | 97.2% | 98.8% |
{30}------------------------------------------------
Formalin ANCA, NOVA View Results
LIU:
| NOVA View interpretation | ||||||
|---|---|---|---|---|---|---|
| Expected result | Site #1 | Site #2 | Site #3 | |||
| Mean LIU | Mean LIU | Mean LIU | ||||
| Sample | n | neg/pos | pattern | |||
| NVA 0224 | 25 | pos | C | 598.4 | 657.4 | 721.9 |
| NVA 0232 | 25 | pos | C | 238.8 | 236.3 | 256.0 |
| NVA 0226 | 25 | pos | C | 174.0 | 178.6 | 194.6 |
| NVA 0225 | 25 | pos | C | 123.7 | 113.0 | 141.0 |
| NVA 0206 | 25 | pos | C | 376.5 | 327.2 | 387.9 |
| NVA 0202 | 25 | pos | C | 310.7 | 263.4 | 319.3 |
| NVA 0210 | 25 | pos | C | 176.6 | 186.3 | 189.6 |
| NVA 0222 | 25 | borderline | C/- | 11.0 | 8.0 | 8.2 |
| NVA 0289 | 25 | neg | n/a | 2.0 | 2.0 | 2.0 |
| NVA 0288 | 25 | neg | n/a | 2.1 | 2.0 | 2.0 |
Summary of SD and %CV:
| Sample | n | Expected result | Average | Within Day | Betweendays | Within site | Between Site | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| neg/pos | pattern | LIU | SD | %CV | SD | %CV | SD | %CV | SD | %CV | ||
| NVA 0224 | 25 | pos | C | 659.2 | 88.6 | 13.4% | 0.0 | 0.0% | 88.6 | 13.4% | 59.2 | 9.0% |
| NVA 0232 | 25 | pos | C | 243.7 | 35.1 | 14.4% | 6.7 | 2.7% | 35.8 | 14.7% | 7.6 | 3.1% |
| NVA 0226 | 25 | pos | C | 182.4 | 22.9 | 12.6% | 18.1 | 9.9% | 29.2 | 16.0% | 5.5 | 3.0% |
| NVA 0225 | 25 | pos | C | 125.9 | 12.8 | 10.1% | 11.2 | 8.9% | 17.0 | 13.5% | 13.0 | 10.3% |
| NVA 0206 | 25 | pos | C | 363.9 | 43.9 | 12.1% | 35.6 | 9.8% | 56.5 | 15.5% | 26.6 | 7.3% |
| NVA 0202 | 25 | pos | C | 297.8 | 36.1 | 12.1% | 41.0 | 13.8% | 54.6 | 18.3% | 22.7 | 7.6% |
| NVA 0210 | 25 | pos | C | 184.6 | 28.6 | 15.5% | 4.9 | 2.6% | 29.0 | 15.7% | 0.0 | 0.0% |
| NVA 0222 | 25 | borderline | C/- | 9.3 | 6.4 | 69.3% | 2.1 | 22.8% | 6.8 | 73.0% | 1.3 | 13.7% |
| NVA 0289 | 25 | neg | n/a | 2.0 | 0.2 | 8.1% | 0.0 | 0.0% | 0.2 | 8.1% | 0.0 | 0.0% |
| NVA 0288 | 25 | neg | n/a | 2.0 | 0.2 | 9.8% | 0.0 | 0.0% | 0.2 | 9.8% | 0.1 | 3.1% |
{31}------------------------------------------------
| Formalin ANCA, manual reading |
|---|
| Qualitative agreement: |
| Expected result | Manual reading | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Site #1 | Site #2 | Site #3 | |||||||
| Sample | n | neg/pos | pattern | Reader #1% neg | Reader #2% pos | Reader #1% neg | Reader #2% pos | Reader #1% neg | Reader #2% pos |
| 1 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% |
| 2 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% |
| 3 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% |
| 4 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% |
| 5 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% |
| 6 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% |
| 7 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% |
| 8 | 25 | borderline | C/- | 0% | 100% | 8% | 92% | 60% | 40% |
| 9 | 25 | neg | n/a | 100% | 0% | 100% | 0% | 100% | 0% |
| 10 | 25 | neg | n/a | 100% | 0% | 100% | 0% | 100% | 0% |
Grade agreement:
| Expected result | Manual reading grades | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Sample | n | neg/pos | pattern | Site #1Reader #1Average grade | Site #2Reader #1Average grade | Site #3Reader #1Average grade | |||
| 1 | 25 | pos | C | 4.0 | 4.0 | 4.0 | 4.0 | 4.0 | 3.9 |
| 2 | 25 | pos | C | 3.0 | 3.2 | 2.4 | 3.2 | 3.0 | 2.6 |
| 3 | 25 | pos | C | 2.1 | 2.5 | 2.5 | 2.5 | 3.0 | 2.0 |
| 4 | 25 | pos | C | 2.0 | 2.2 | 1.3 | 1.9 | 2.4 | 1.6 |
| 5 | 25 | pos | C | 3.6 | 3.5 | 3.2 | 3.3 | 4.0 | 2.9 |
| 6 | 25 | pos | C | 3.0 | 3.0 | 2.4 | 3.2 | 4.0 | 2.6 |
| 7 | 25 | pos | C | 2.0 | 2.0 | 2.0 | 2.4 | 3.0 | 1.6 |
| 8 | 25 | borderline | C/- | 1.0 | 0.9 | 0.4 | 1.0 | 1.0 | 1.0 |
| 9 | 25 | neg | n/a | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| 10 | 25 | neg | n/a | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
{32}------------------------------------------------
Formalin ANCA, digital reading Qualitative agreement:
| Digital reading | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Expected result | Site #1 | Site #2 | Site #3 | ||||||||
| Reader #1 | Reader #2 | Reader #1 | Reader #2 | Reader #1 | Reader #2 | ||||||
| Sample | n | neg/pos | pattern | %neg | % pos | %neg | % pos | %neg | % pos | %neg | % pos |
| 1 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 2 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 3 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 4 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 4% | 96% |
| 5 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 6 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 7 | 25 | pos | C | 0% | 100% | 0% | 100% | 0% | 100% | 0% | 100% |
| 8 | 25 | borderline | C/- | 28% | 72% | 48% | 52% | 92% | 8% | 100% | 0% |
| 9 | 25 | neg | n/a | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% |
| 10 | 25 | neg | n/a | 100% | 0% | 100% | 0% | 100% | 0% | 100% | 0% |
Grade agreement:
| Expected result | Digital reading grades | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Site #1 | Site #2 | Site #3 | |||||||
| Sample | n | neg/pos | pattern | Reader #1 | Reader #2 | Reader #1 | Reader #2 | Reader #1 | Reader #2 |
| Average grade | Average grade | Average grade | |||||||
| 1 | 25 | pos | C | 4.0 | 4.0 | 4.0 | 4.0 | 4.0 | 3.2 |
| 2 | 25 | pos | C | 3.0 | 3.0 | 2.2 | 3.0 | 3.4 | 2.0 |
| 3 | 25 | pos | C | 2.2 | 2.0 | 2.0 | 2.1 | 2.6 | 1.0 |
| 4 | 25 | pos | C | 1.4 | 1.4 | 1.4 | 1.6 | 2.4 | 1.0 |
| 5 | 25 | pos | C | 3.8 | 3.1 | 3.0 | 3.0 | 4.0 | 3.0 |
| 6 | 25 | pos | C | 3.1 | 2.8 | 2.2 | 2.5 | 3.8 | 2.1 |
| 7 | 25 | pos | C | 2.0 | 2.0 | 1.8 | 2.0 | 2.6 | 1.0 |
| 8 | 25 | borderline | C/- | 0.7 | 0.5 | 0.1 | 0.9 | 0.0 | 0.0 |
| 9 | 25 | neg | n/a | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| 10 | 25 | neg | n/a | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
{33}------------------------------------------------
Formalin ANCA
Agreement between Operator 1 and Operator 2 at each site:
| % Overall Agreement (Positive/Negative) between operators (per site) for Formalin | |||
|---|---|---|---|
| Inova | Site #2 | Site #3 | |
| Manual Reading | 99.2% | 100.0% | 94.0% |
| Digital Image Reading | 97.2% | 99.6% | 91.6% |
14.3 Linearity and Analytical Measuring Range (AMR)
N/A
14.4 Interference
The interference study was performed according to CLSI EPO7-A2, Interference Testing in Clinical Chemistry; Approved Guideline - Second Edition.
Interference by bilirubin, hemoglobin, triglycerides, cholesterol, RF IgM, Human Immunoglobulin (IgG), Rituximab, Methylprednisolone, Cyclophosphamide, Methotrexate, Azathioprine was assessed using the following materials and concentrations. The Table below contains all three concentration levels that were tested:
| Interfering substance | ManufacturerPart Number | Lot number | Concentration #1tested | Concentration #2tested | Concentration #3tested |
|---|---|---|---|---|---|
| Bilirubin, conjugated | EMD 201102 | DU3038000 | 100 mg/dL | 50 mg/dL | 25 mg/dL |
| Hemoglobin | SIGMA H7379 | 051M7004V | 200 mg/dL | 100 mg/dL | 50 mg/dL |
| Triglicerydes | SCIPAC P235-8 | 1201-146 | 1000 mg/dL | 500 mg/dL | 250 mg/dL |
| Cholesterol | SCIPAC P235-8 | 1201-146 | 224.3 mg/dL | 112.1 mg/dL | 56 mg/dL |
| RF IgM | QC #16 | ZG0024783 | 56 IU/mL | 39.2 IU/mL | 28.02 IU/mL |
| Interfering substance | ManufacturerPart Number | Lot number | Concentration#1 tested | Concentration #2tested | Concentration #3 |
|---|---|---|---|---|---|
| Human Immunoglobulin (IgG) | 16-16-090701 | 1G2012-05 | 70 mg/mL | 35 mg/mL | 17.5 mg/mL |
| Rituximab | SAP-10063468 | n/a | 7.6 mg/mL | 3.8 mg/mL | 1.9 mg/mL |
| Methylprednisolone | 1435003 | I0E170 | 0.85 mg/mL | 0.425 mg/mL | 0.213 mg/mL |
| Cyclophosphamide | PHR1404 | LRAA2198 | 4.1 mg/mL | 2.05 mg/mL | 1.025 mg/mL |
| Methotrexate | 1414003 | R020L0 | 0.01 mg/mL | 0.005 mg/mL | 0.0025 mg/mL |
| Azathioprine | PHR1282 | LRAA9079 | 0.03 mg/mL | 0.015 mg/mL | 0.0075 mg/mL |
Five specimens were tested (one negative, one low anti-MPO positive, one strong anti-MPO positive, one low anti-PR3 positive, one strong anti-PR3 positive). Interfering substances (see tables above) were spiked into every specimen at three different concentrations (see tables above) in 10% of total specimen
{34}------------------------------------------------
volume, and the resulting samples were assessed in triplicates according to the standard protocol (diluted in 1:20 and processed on Ethanol ANCA and Formalin ANCA slides). The concentrations shown above are final (testing) concentrations in the sample after spiking. To assess interference with rheumatoid factor (RF), 10%, 30% and 50% (volume) RF positive sample was added to the test samples. All samples were processed with NOVA Lite DAPI ANA kit, and read with NOVA View. Digital images were interpreted and confirmed. Moreover, all slides were read by the same operator with manual microscopy. Appropriate controls were made by adding 10% (volume) sample diluent to the same samples and for testing for RF interference, adding 10%, 30% and 50% (volume) sample diluent to the samples.
Acceptance criteria:
- Grades obtained on samples with interfering substances are within ± 1 reactivity . grade of those obtained on the control samples, spiked with diluent.
No interference was detected with bilirubin up to 100 mg/dL, hemoglobin up to 200 mg/dL, triglycerides up to 1000 mg/dL, cholesterol up to 224.3 mg/dL, RF IgM up to 56 IU/mL, Human Immunoglobulin up to 35 mg/dL, Rituximab up to 7.6 mg/mL, Methy|prednisolone up to 0.85 mg/mL, Cyclophosphamide up to 4.1 mg/mL, Methotrexate up to 0.01 mg/mL and Azathioprine up to 0.03 mg/mL.
Reactivity grades of samples containing the interfering substance were within ± one grade of the control samples with both manual and digital reading.
14.5 Cross-reactivity
Cross reactivity with autoimmune and infectious agent antibodies was examined in the clinical patient population shown in the tables below (n=151), and 25%, 26% and 25% cross-reactivity was shown on Ethanol-fixed slides with NOVA View software interpretation and digital image interpretation, and 8%, 8% and 11% cross-reactivity was shown on Formalin-fixed slides, respectively:
| Diagnosis | N | NOVA View pos | Manual pos | Digital pos | |||
|---|---|---|---|---|---|---|---|
| Infectious Disease | 40 | 14 | 35% | 14 | 35% | 14 | 35% |
| Autoimmune thyroiddisease | 15 | 14 | 93% | 13 | 87% | 13 | 87% |
| Celiac (tTG IgA POS) | 61 | 8 | 13% | 9 | 15% | 8 | 13% |
| Rheumatoid Arthritis (RA) | 35 | 2 | 6% | 3 | 9% | 2 | 6% |
| Total | 151 | 38 | 25% | 39 | 26% | 37 | 25% |
Ethanol ANCA cross-reactivity with autoimmune and infectious agent antibodies:
Formalin ANCA cross-reactivity with autoimmune and infectious agent antibodies:
| Diagnosis | N | NOVA View pos | Manual pos | Digital pos | ||
|---|---|---|---|---|---|---|
| Infectious Disease | 40 | 3 | 8% | 2 5% | 3 | 8% |
| Autoimmune thyroid disease | 15 | 6 | 40% | 6 40% | 7 | 47% |
| Celiac (tTG IgA POS) | 61 | 3 | 5% | 3 5% | 4 | 7% |
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NOVA Lite® DAPI ANCA Ethanol and Formalin
| Rheumatoid Arthritis (RA) | 35 | 0 | 0% | 1 | 3% | 2 | 6% |
|---|---|---|---|---|---|---|---|
| Total | 151 | 12 | 8% | 12 | 8% | 16 | 11% |
It is known that ANA and other anti-cell antibodies may interfere with ANCA detection by causing nuclear and/or cytoplasmic staining. It is assumed that the main cause of interference shown in the population above is the result of ANA or in the samples.
Therefore cross-reactivity caused by known ANA positive samples was examined by testing 25 analytically characterized samples, and cross reactivity was found with 76%, 80% and 80% of ANA positive samples on Ethanol-fixed slides with NOVA View software interpretation, manual interpretation and digital image interpretation, and 24%, 32% and 24% cross-reactivity was shown on Formalin-fixed slides, respectively:
| ANA positive sample | Number and % of Ethanol ANCA positive samples | ||
|---|---|---|---|
| NOVA View | Manual | Digital | |
| Homogeneous (n=5) | 5100% | 5100% | 5100% |
| Speckled (n=5) | 480% | 480% | 480% |
| Centromere (n=5) | 5100% | 5100% | 5100% |
| Nucleolar (n=5) | 360% | 360% | 360% |
| Nuclear dots (n=5) | 240% | 360% | 360% |
| Total | 1976% | 2080% | 2080% |
Ethanol ANCA cross-reactivity with ANA:
Formalin ANCA cross-reactivity with ANA:
| ANA positive sample | Number and % of Formalin ANCA positive samples | ||
|---|---|---|---|
| NOVA View | Manual | Digital | |
| Homogeneous (n=5) | 4 80% | 4 80% | 4 80% |
| Speckled (n=5) | 1 20% | 1 20% | 1 20% |
| Centromere (n=5) | 1 20% | 1 20% | 1 20% |
| Nucleolar (n=5) | 0 0% | 1 20% | 0 0% |
| Nuclear dots (n=5) | 0 0% | 1 20% | 0 0% |
| Total | 6 24% | 8 32% | 6 24% |
The following statements were added to the package insert of the kits under "Limitations of the Procedure":
Ethanol ANCA:
ANA positive samples may react with the nuclei of ethanol-fixed neutrophils, masking or mimicking ANCA. Positive IIF results should be confirmed by antigen specific solid phase assay for anti-MPO and anti-PR3.
Formalin ANCA:
{36}------------------------------------------------
ANA positive samples may show weak nuclear fluorescence on formalin fixed neutrophil granulocytes. 15. Cutoff
The serum dilution of 1:20 was selected to provide optimal clinical sensitivity and specificity, and it is the same as that of the predicate device.
Sera from 90 apparently healthy subjects (44 females, 46 males) and from 20 patients with infectious diseases (10 females, 5 unknown) were tested. The number of positive results is shown in the Table below:
| NOVA View softwareinterpretation | Manual reading | Digital reading | |
|---|---|---|---|
| Ethanol ANCA | 13 | 15 | 14 |
| Formalin ANCA | 4 | 2 | 2 |
The performance of this serum dilution has been validated as described in sections "Clinical performance" and "Expected values".
16. Comparison with the predicate device
16.1 Conjugate comparison
The conjugate (P/N 508102) is the same that is used in the NOVA Lite DAPI ANA Kit (k 155055). It is the same conjugate as that of the predicate device (P/N 508113), but with blue fluorescent dye DAPI (4',6diamidino-2-phenylindole) added.
To demonstrate the equivalent performance of the conjugate with and without DAPI, a comparison study was performed.
Comparison was performed on 36 specimens (analytically characterized serum samples and controls), in addition to a diluent blank, with FITC IgG Conjugate (508113) and FITC IgG Conjugate with DAPI (508102), using ANCA Ethanol and ANCA Formalin reagents. Results were manually interpreted. Acceptance criteria:
- . Qualitative agreement: ≥ 90%
- Grade agreement: ≥ 90% within ± 1 reactivity grade
Moreover, endpoint titration was performed on 6 positive samples with both FITC IgG Conjugate (508113) and FITC IgG Conjugate with DAPI (508102).
Acceptance criteria:
- . The endpoint dilution is within ±1 dilution step between the two conjugates
The qualitative agreement and the grade agreement between the result obtained with the predicate and the new conjugate was 100% on both Ethanol and Formalin ANCA slides.
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| Grade 508102 | |||||
|---|---|---|---|---|---|
| Ethanol | 0 | 2 | 3 | 4 | Total |
| Grade 508113 | |||||
| 0 | 14 | 0 | 0 | 0 | 14 |
| 2 | 0 | 2 | 1 | 0 | 3 |
| 3 | 0 | 0 | 5 | 2 | 7 |
| 4 | 0 | 0 | 1 | 11 | 12 |
| Total | 14 | 2 | 7 | 13 | 36 |
| Formalin | Grade 508102 | |||||
|---|---|---|---|---|---|---|
| Grade 508113 | 0 | 1 | 2 | 3 | 4 | Total |
| 0 | 20 | 0 | 0 | 0 | 0 | 20 |
| 1 | 0 | 2 | 0 | 0 | 0 | 2 |
| 2 | 0 | 0 | 1 | 1 | 0 | 2 |
| 3 | 0 | 0 | 0 | 1 | 0 | 1 |
| 4 | 0 | 0 | 0 | 1 | 10 | 11 |
| Total | 20 | 2 | 1 | 3 | 10 | 36 |
Endpoint titers obtained with the new conjugate were within ±1 dilution step of those obtained with the predicate conjugate:
| Endpoint titer, Ethanol | Endpoint titer, Formalin | |||
|---|---|---|---|---|
| Sample ID | 508113 | 508102 | 508113 | 508102 |
| pANCA pos (PS0031/120401) | 320 | 320 | 320 | 320 |
| pANCA pos (PS0031/720005) | 640 | 640 | 320 | 320 |
| pANCA pos (PS0031/920124) | 1280 | 1280 | 320 | 320 |
| cANCA pos (PS0030/020187) | 5120 | 5120 | 2560 | 2560 |
| cANCA pos (PS0030/070828) | 1280 | 2560 | 1280 | 1280 |
| cANCA pos (PS0030/090263) | 1280 | 1280 | 2560 | 2560 |
16.2 Method comparison
Results that were obtained with the NOVA Lite DAPI ANCA (Ethanol) Kit and NOVA Lite DAPI ANCA (Formalin) Kit by NOVA View software interpretation, digital image reading and manual reading were compared to those obtained with the manual interpretation of the predicate device. Study includes 100 samples (50 P-ANCA and 50 C-ANCA) and disease control groups (infectious disease, Systemic Lupus Erythemtosus, Progressive Systemic Sclerosis, Rheumatoid arthritis and Chronic Kidney Disease) Qualitative agreement, pattern agreement and grade agreement were calculated between NOVA View software interpretation, manual reading and digital image reading.
{38}------------------------------------------------
Acceptance criteria:
- Qualitative agreement: ≥ 80% (this acceptance criteria only applies to manual and digital because NOVA View always has to be confirmed by digital interpretation)
- Grade agreement: ≥ 90% within ± 1 reactivity grade ●
- Pattern agreement: ≥ 80% between manual and digital interpretation.
The composition of the internal validation study is shown below:
| Characterized MPO/PR3 | 119 |
|---|---|
| Infectious Disease | 20 |
| Systemic Lupus Erythematosus | 35 |
| Progressive Systemic Sclerosis | 20 |
| Rheumatoid arthritis | 34 |
| Inflammatory Bowel Disease | 21 |
| Chronic Kidney Disease | 18 |
| Total | 267 |
Agreement results are summarized below for Inova Only:
Ethanol ANCA
Qualitative agreement:
| n= 267 | Positiveagreement (%)(95% CI) | Negativeagreement (%)(95% CI) | Total agreement(%) (95% CI) |
|---|---|---|---|
| 708298 manual vs704338 manual | 91.8 (87.6-94.7) | 91.2 (77.0-97.0) | 91.8 (87.8-94.5) |
| 708298 manual vs 704338 digital | 80.3 (74.7-84.9) | 97.1 (85.1-99.5) | 82.4 (77.4-86.5) |
| 708298 manual vs 704338 NOVA View | 76.4 (70.5-81.4) | 97.1 (85.1-99.5) | 79.0 (73.7-83.5) |
Grade agreement:
| 708298 Manual Grade | ||||||
|---|---|---|---|---|---|---|
| 704338 ManualGrade | 0 | 1+ | 2+ | 3+ | 4+ | Total |
| 0 | 31 | 10 | 9 | 0 | 0 | 50 |
| 1+ | 3 | 50 | 10 | 1 | 0 | 64 |
| 2+ | 0 | 5 | 46 | 13 | 1 | 65 |
| 3+ | 0 | 0 | 4 | 21 | 7 | 32 |
| 4+ | 0 | 1 | 1 | 8 | 46 | 56 |
| Total | 34 | 66 | 70 | 43 | 54 | 267 |
| Within ± 2 grades | 99.6% |
{39}------------------------------------------------
| 708298 Manual Grade | |||||||
|---|---|---|---|---|---|---|---|
| 704338 DigitalGrade | 0 | 1+ | 2+ | 3+ | 4+ | Total | |
| 0 | 33 | 35 | 11 | 0 | 0 | 79 | |
| 1+ | 1 | 28 | 25 | 3 | 0 | 57 | |
| 2+ | 0 | 2 | 24 | 11 | 1 | 38 | |
| 3+ | 0 | 0 | 8 | 18 | 4 | 30 | |
| 4+ | 0 | । | 2 | ਹ ਹ | 49 | રૂડે જિલ્લામાં આવેલું એક ગામનાં મુખ્યત્વે ખેત-ઉપર તાલુકામાં આવેલું એક ગામનાં મુખ્યત્વે ખેત-ઉપર તાલુકામાં આવેલું એક ગામનાં મુખ્યત્વે ખાતે ખાતમજૂરી તેમ જ પશુપાલન છે. આ ગામમા | |
| Total | 34 | ୧୧ | 70 | 43 | 54 | 267 |
Within ± 2 grades
99.6%
Pattern agreement:
| n=267 | Pattern agreement withpos/neg disagreement |
|---|---|
| 708298 Manual vs 704338 Manual | 89.9% |
| 708298 Manual vs 704338 Digital | 80.1% |
Formalin ANCA
Qualitative agreement:
| n= 267 | Positive agreement(%) (95% CI) | Negative agreement(%) (95% CI) | Total agreement (%)(95% CI) |
|---|---|---|---|
| 708297 manualvs704337 manual | 94.4 (89.8-97.0) | 90.5 (83.4-94.7) | 92.9 (89.2-95.4) |
| 708297 manual vs704337 digital | 79.0 (72.1-84.6) | 99.0 (94.8-99.8) | 86.9 (82.3-90.4) |
| 708297 manual vs704337 NOVA View | 72.2 (64.9-78.5) | 97.1 (91.9-99.0) | 82.0 (77.0-86.2) |
Grade agreement:
| 708298 Manual Grade | ||||||
|---|---|---|---|---|---|---|
| 704338 ManualGrade | 0 | 1+ | 2+ | 3+ | 4+ | Total |
| 0 | 95 | 9 | 0 | 0 | 0 | 104 |
| 1+ | 9 | 36 | 12 | 1 | 0 | 58 |
| 2+ | 1 | 4 | 36 | 8 | 2 | 51 |
| 3+ | 0 | 0 | 1 | 23 | 4 | 28 |
| 4+ | 0 | 0 | 0 | 1 | 25 | 26 |
| Total | 105 | 49 | 49 | 33 | 31 | 267 |
| Within ± 2 grades | 100% |
{40}------------------------------------------------
| 708298 Manual Grade | ||||||
|---|---|---|---|---|---|---|
| 704338 Digital Grade | 0 | 1+ | 2+ | 3+ | 4+ | Total |
| 0 | 104 | 27 | 7 | 0 | 0 | 138 |
| 1+ | 1 | 21 | 13 | 1 | 0 | 36 |
| 2+ | 0 | 1 | 23 | 6 | 1 | 31 |
| 3+ | 0 | 0 | 6 | 21 | 3 | 30 |
| 4+ | 0 | 0 | 0 | 5 | 27 | 32 |
| Total | 105 | 49 | 49 | 33 | 31 | 267 |
| Within ± 2 grades | 100% |
Within ± 2 grades
Pattern agreement:
| n=267 | Pattern agreement with pos/neg disagreement |
|---|---|
| 708297 Manual vs 704337 Manual | 92.1% |
| 708297 Manual vs 704337 Digital | 86.9% |
17. Clinical performance
Prevalence of ANCA positivity on Formalin and Ethanol slides for NOVA View manual reading and digital interpretation.
| Diagnosis | N | NOVA View Pos (% pos) | Manual pos (% pos) | Digital pos (% pos) | |||
|---|---|---|---|---|---|---|---|
| Ethanol | Formalin | Ethanol | Formalin | Ethanol | Formalin | ||
| ANCA Associated Vasculitis (AAV)** | 185 | 111(60%) | 113 (61%) | 131 (71%) | 139 (75%) | 129 (70%) | 134 (72%) |
| Characterized MPO/PR3 | 59 | 57 (97%) | 56 (95%) | 59 (100%) | 59 (100%) | 59 (100%) | 58 (98%) |
| Infectious Disease | 40* | 5 (13%) | 4 (10%) | 12 (30%) | 6 (15%) | 9 (23%) | 5 (13%) |
| Autoimmune thyroid disease | 15* | 14 (93%) | 6 (40%) | 13 (87%) | 6 (40%) | 13 (87%) | 7 (47%) |
| Chronic Kidney Disease (CKD) | 18* | 9 (50%) | 0 (0%) | 13 (72%) | 1 (6%) | 10 (56%) | 1 (6%) |
| Dermatitis | 12* | 3 (25%) | 0 (0%) | 4 (33%) | 0 (0%) | 3 (25%) | 0 (0%) |
| Diabetes Type II | 20* | 8 (40%) | 0 (0%) | 8 (40%) | 0 (0%) | 8 (40%) | 1 (5%) |
| Celiac (tTG IgA POS) | 61* | 11 (18%) | 5 (8%) | 14 (23%) | 4 (7%) | 13 (21%) | 3 (5%) |
| Chronic Obstructive Pulmonary Disease (COPD) | 20* | 8 (40%) | 0 (0%) | 9 (45%) | 2 (10%) | 9 (45%) | 2 (10%) |
| Rheumatoid Arthritis (RA) | 35* | 25 (71%) | 6 (17%) | 26 (74%) | 5 (14%) | 25 (71%) | 5 (14%) |
| Crohn's Disease | 11* | 6 (55%) | 3 (27%) | 6 (55%) | 2 (18%) | 6 (55%) | 2 (18%) |
| Ulcerative Colitis | 15* | 4 (27%) | 0 (0%) | 8 (53%) | 2 (13%) | 5 (33%) | 1 (7%) |
| Allergy | 7* | 2 (29%) | 0 (0%) | 3 (43%) | 1 (14%) | 2 (29%) | 2 (29%) |
| Apparently healthy | 89 | 4 (4%) | 0 (0%) | 8 (9%) | 0 (0%) | 4 (4%) | 0 (0%) |
| Progressive systemic sclerosis | 25* | 14 (56%) | 1 (4%) | 18 (72%) | 3 (12%) | 14 (56%) | 2 (8%) |
| Sinusitis | 18* | 1 (6%) | 0 (0%) | 5 (28%) | 1 (6%) | 2 (11%) | 0 (0%) |
| Systemic Lupus Erythematosus | 23* | 16 (70%) | 4 (17%) | 18 (78%) | 9 (39%) | 15 (65%) | 5 (22%) |
| Total | 653 |
*used for specificity calculation
{41}------------------------------------------------
| NOVA View Pos (% pos) | Manual pos (% pos) | Digital pos (% pos) | |||||
|---|---|---|---|---|---|---|---|
| Diagnosis | N | Ethanol | Formalin | Ethanol | Formalin | Ethanol | Formalin |
| GPA | 113 | 53 (47%) | 67 (59%) | 67 (59%) | 83 (73%) | 65 (57%) | 80 (71%) |
| MPA | 21 | 18 (86%) | 12 (57%) | 20 (95%) | 15 (71%) | 20 (95%) | 15 (71%) |
| eGPA | 12 | 3 (25%) | 2 (17%) | 6 (50%) | 3(25%) | 5 (42%) | 3 (25%) |
| UndifferentiatedAAV | 39 | 37 (95%) | 32 (82%) | 38 (97%) | 38 (97%) | 39 (100%) | 36 (93%) |
**The specific ANCA Associated Vasculitides samples tested are outlined in the table below
17.1 Clinical sensitivity and specificity
To assess clinical performance, a clinical study was performed by Inova Diagnostics on 653 clinically or analytically characterized serum samples were analytically characterized (anti-MPO/PR3 positive) samples and 89 samples were derived from healthy individuals; these samples were excluded from the sensitivity and specificity calculations.
Additionally, 287 clinically or analytically characterized serum samples were tested at Inova (Site#1) and at two external clinical sites (Site#2 and Site #3) with both Ethanol and Formalin ANCA, as described in section "Between sites/instruments reproducibility". The contained 49 analytically characterized samples that were excluded from the sensitivity and specificity calculations (clinical cohort n=238). The composition of the combined clinical cohort (n=653) is described in the "Clinical Performance" section.
Sensitivity (on ANCA-associated vasculitis – AAV) and specificity, calculated on the combined population, are shown below.
Ethanol:
Digital:
| cANCA Pattern | pANCA Pattern | |||
|---|---|---|---|---|
| Sensitivity (%)(95% CI) | Specificity (%)(95% CI) | Sensitivity (%)(95% CI) | Specificity (%)(95% CI) | |
| GPA | 29.2 (21.6-38.23) | 91.6 (88.0-94.1) | 27.4 (20.1-36.3) | 66.6 (61.2-71.5) |
| MPA | 4.8 (0.8-22.7) | 91.6 (88.0-94.1) | 90.5 (71.1-97.3) | 66.6 (61.2-71.5) |
| eGPA | 8.3 (1.5-35.4) | 91.6 (88.0-94.1) | 33.3 (13.8-60.9) | 66.6 (61.2-71.5) |
| AAV | 24.0 (17.8-31.5) | 91.6 (88.0-94.1) | 37.0 (29.6-45.1) | 66.6 (61.2-71.5) |
{42}------------------------------------------------
Manual:
| cANCA Pattern | pANCA Pattern | |||
|---|---|---|---|---|
| Sensitivity (%)(95% CI) | Specificity (%)(95% CI) | Sensitivity (%)(95% CI) | Specificity (%)(95% CI) | |
| GPA | 29.2 (21.6-38.23) | 91.3 (87.6-93.9) | 30.1 (22.4-39.1) | 59.7 (54.2-64.9) |
| MPA | 4.8 (0.8-22.7) | 91.3 (87.6-93.9) | 90.5 (71.1-97.3) | 59.7 (54.2-64.9) |
| eGPA | 8.3 (1.5-35.4) | 91.3 (87.6-93.9) | 33.3 (13.8-60.9) | 59.7 (54.2-64.9) |
| AAV | 24.0 (17.8-31.5) | 91.3 (87.6-93.9) | 39.0 (31.5-47.1) | 59.7 (54.2-64.9) |
NOVA View:
| cANCA Pattern | pANCA Pattern | |||
|---|---|---|---|---|
| Sensitivity (%)(95% CI) | Specificity (%)(95% CI) | Sensitivity (%)(95% CI) | Specificity (%)(95% CI) | |
| GPA | 12.4 (7.2-20.4) | 95.9 (93.0-97.7) | 25.8 (18.1-35.3) | 69.6 (64.1-74.6) |
| MPA | 0.0 (0.0-15.5) | 95.9 (93.0-97.7) | 85.7 (65.4-95.0) | 69.6 (64.1-74.6) |
| eGPA | 0.0 (0.0-25.9) | 95.9 (93.0-97.7) | 18.2 (5.1-47.7) | 69.6 (64.1-74.6) |
| AAV | 9.3 (5.4-15.6) | 95.9 (93.0-97.7) | 9.3 (5.4-15.6) | 69.6 (64.1-74.6) |
Formalin (C-ANCA):
Digital:
| Sensitivity (%) (95% CI) | Specificity (%) (95% CI) | |
|---|---|---|
| GPA | 70.8 (61.8-78.4) | 91.3 (87.6-93.9) |
| MPA | 71.4 (50.0-86.2) | 91.3 (87.6-93.9) |
| eGPA | 25.0 (8.9-53.2) | 91.3 (87.6-93.9) |
| AAV | 67.1 (59.1-74.2) | 91.3 (87.6-93.9) |
Manual:
| Sensitivity (%) (95% CI) | Specificity (%) (95% CI) | |
|---|---|---|
| GPA | 73.5 (64.6-80.7) | 89.7 (85.9-92.6) |
| MPA | 71.4 (50.0-86.2) | 89.7 (85.9-92.6) |
| eGPA | 16.7 (4.7-44.8) | 89.7 (85.9-92.6) |
| AAV | 68.5 (60.6-75.5) | 89.7 (85.9-92.6) |
NOVA View:
| Sensitivity (%) (95% CI) | Specificity (%) (95% CI) | |
|---|---|---|
| GPA | 38.7 (28.5-50.0) | 98.7 (96.6-99.5) |
| MPA | 47.1 (26.2-69.0) | 98.7 (96.6-99.5) |
| eGPA | 16.7 (4.7-44.8) | 98.7 (96.6-99.5) |
| AAV | 37.5 (28.8-47.1) | 98.7 (96.6-99.5) |
{43}------------------------------------------------
Sensitivity and specificity were also calculated on the 238 clinical samples that were run during the between sites reproducibility study at all three sites (patterns were not taken into consideration when calculating sensitivity and specificity in this section):
Site #1 (Inova), Ethanol ANCA
| n=238 | Sensitivity (%)(95% CI) | Specificity (%)(95% CI) |
|---|---|---|
| Manual | 88.8 (80.0-94.0) | 50.6 (42.9-58.3) |
| Digital | 87.5 (78.5-93.1) | 57.6 (49.8-65.0) |
| NOVA View | 85.0 (75.6-91.2) | 62.7 (54.9-69.8) |
Site #1 (Inova), Formalin ANCA
| n=238 | Sensitivity (%)(95% CI) | Specificity (%)(95% CI) |
|---|---|---|
| Manual | 92.5 (84.6-96.5) | 90.5 (84.9-94.2) |
| Digital | 88.8 (80.0-94.0) | 92.4 (87.2-95.6) |
| NOVA View | 83.8 (74.2-90.3) | 96.8 (92.8-98.6) |
Site #2, Ethanol ANCA
| n=238 | Sensitivity (%) (95% CI) | Specificity (%) (95% CI) |
|---|---|---|
| Manual results | 75.0 (64.5-83.2) | 57.0 (49.2-64.4) |
| Digital results | 71.3 (60.5-80.0) | 65.6 (57.9-72.6) |
| NOVA View results | 70.0 (59.2-78.9) | 69.5 (61.8-76.2) |
Site #2, Formalin ANCA
| n=238 | Sensitivity (%)(95% CI) | Specificity (%)(95% CI) |
|---|---|---|
| Manual | 80.0 (70.0-87.3) | 90.5 (84.9-94.2) |
| Digital | 81.3 (71.3-88.3) | 94.3 (89.5-97.0) |
| NOVA View | 76.3 (65.9-84.2) | 94.3 (89.5-97.0) |
Site #3, Ethanol ANCA
| n=238 | Sensitivity (%)(95% CI) | Specificity (%)(95% CI) |
|---|---|---|
| Manual | 72.5 (61.9-81.1) | |
| Digital | 72.5 (61.9-81.1) | 65.8 (58.1-72.8) |
| NOVA View | 70.0 (59.2-78.9) | 68.4 (60.7-75.1) |
{44}------------------------------------------------
Site #3, Formalin ANCA
| n=238 | Sensitivity (%)(95% CI) | Specificity (%)(95% CI) |
|---|---|---|
| Manual | 77.5 (67.2-85.3) | 93.0 (88.0-96.1) |
| Digital | 76.3 (65.9-84.2) | 94.3 (89.5-97.0) |
| NOVA View | 75.0 (64.5-83.2) | 96.8 (92.8-98.6) |
The reason for the low specificity of Ethanol ANCA testing is assumed to be the consequence of ANA interference/cross-reactivity, as many of the control groups (rheumatoid arthritis, thyroid disease, celiac disease, etc.) are known to have an ANA prevalence above that of the healthy population. As ANCA is tested in 1:20 serum dilution, this effect is augmented. However, it is also known that ANA becomes negative, or shows a highly decreased staining intensity on Formalin fixed ANCA slides. Therefore the relationship between Ethanol and Formalin ANCA results was assessed on the control population of the between sites reproducibility study (n=158).
The vast majority of Ethanol ANCA positive samples became negative on Formalin ANCA, as shown in the Tables below (only Inova data are shown):
| NOVA View Result Formalin | |||
|---|---|---|---|
| NOVA View Result Ethanol | neg | pos | Total |
| neg | 99 | 0 | 99 |
| pos | 54 | 5 | 59 |
| Total | 153 | 5 | 158 |
| Manual Result Formalin | |||
|---|---|---|---|
| Manual Result Ethanol | neg | pos | Total |
| neg | 78 | 2 | 80 |
| pos | 65 | 13 | 78 |
| Total | 143 | 15 | 158 |
| Digital Results, Formalin | |||
|---|---|---|---|
| Digital Results Ethanol | neg | pos | Total |
| neg | 90 | 1 | 91 |
| pos | 56 | 11 | 67 |
| Total | 146 | 12 | 158 |
It was confirmed that the remaining Formalin positive samples showed significant decrease in staining intensity, implying that those were ANA positive samples:
| Median LIU,NOVA View | Median grade,manual | Median grade,digital | |
|---|---|---|---|
| Ethanol ANCA | 553 | 2.5 | 2.5 |
| Formalin ANCA | 76 | 1.0 | 1.0 |
{45}------------------------------------------------
17.2 Expected values
Expected values were analyzed on 89 samples from apparently healthy subjects: 29 females, 6 with unknown gender, with mean age of 45.7 years (range of 18-68).
With Ethanol ANCA, there were 4 positive results with NOVA View software interpretation, 8 with manual interpretation, and 4 with digital interpretation.
There were no positive results with Formalin ANCA testing, by any interpretation method.
18. System description
18.1 NOVA View Automated Fluorescence Microscope and Software
18.1.1 NOVA View Automated Fluorescence Microscope
NOVA View® Automated Fluorescence Microscope is an automated system consisting of a fluorescence microscope and software that acquires, analyzes, stores and displays digital images of stained indirect immunofluorescent slides. It is intended as an aid in the detection and classification of certain antibodies by indirect immunofluorescence technology. The device can only be used with cleared or approved in vitro diagnostic assays that are indicated for use with the device. A trained operator must confirm results generated with the device.
The NOVA View device has been cleared by the FDA in DEN140039. Subsequently, the use of NOVA View with AUTOLoader has been cleared in K153150.
Device description and Principle of Operation were described in DEN140039 and K153150, and remained unchanged for this submission.
18.1.2 Software
Level of Concern: Moderate.
The NOVA View software version in this submission contains the following changes compared to the version in K153150:
Addition of ANCA module, containing ANCA Ethanol and ANCA Formalin applications, and ANCA SWT application.
When ANCA slides are analyzed by NOVA View, digital images of representative fields of view of the well are captured. At the same time when digital images are taken, NOVA View measures the FITC light intensity of the cells that are included in the region. NOVA View reports the measured fluorescence intensity in units of Light Intensity Units (LIU).
NOVA View provides the trained operator with the acquired digital images and the following supportive information:
- LIU value
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Negative/positive classification
-
Pattern information
| Patterns reported by NOVA View (Ethanol ANCA) | |
|---|---|
| P | P-ANCA |
| C | C-ANCA |
| U | Unrecognized |
| Patterns reported by NOVA View (Formalin ANCA) | |
|---|---|
| N | Nuclear |
| C | Cytoplasmic |
| U | Unrecognized |
Additionally, five programmable pattern buttons are available on the user interface that can be customized based on the end user lab's preferences and routine nomenclature.
NOVA View Ethanol ANCA Single Well Titer (SWT)
The SWT is a software application that estimates the endpoint titer (e.g., the highest dilution that gives positive result) for wells with a positive reaction with Ethanol ANCA, based on the obtained fluorescence intensity and pattern. The highest titer that can be differentiated is 1:1280 for both P-ANCA and C-ANCA. Above this value the NOVA View reports ≥ 1280 titer.
The SWT function was established on 10 anti-MPO (P-ANCA) and 10 anti-PR3 (C-ANCA) positive samples, containing various levels of antibodies. Two-fold serial dilutions were made from each sample, starting from 1:20, up to 1:10,240. Each dilution was processed on ANCA Ethanol slides, and the results were interpreted by NOVA View and by manual reading. Based on the results that were generated on these samples, P-ANCA and C-ANCA specific LIU curves were established based on 4-PL logistic curve fitting. NOVA View uses these built-in curves for titer determination.
The validation of the SWT function was performed on altogether 24 anti-MPO (P-ANCA) and 23 anti-PR3 (C-ANCA) positive samples. All samples were serially diluted and manually titrated, and also run on the NOVA View. SWT was determined for all samples.
Acceptance criteria:
- . SWT is within ± 2 dilution steps of that of the manual titer and the digital titer.
Based on 47 samples, 76.6% of SWT results were within ± 1 dilution step of that of the manual titer, and 91.5% were within ± 1 dilution step of that of the digital titer, and 97.7% of SWT results were within ± 2 dilution steps of that of both the manual titer and digital titer. One out of the 47 samples was outside of this range.
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| SWT, n=47 | within ± 1dilution step | within ± 2dilution steps |
|---|---|---|
| Manual endpoint | 76.6% | 97.9% |
| Digital endpoint | 91.5% | 97.9% |
Additionally, SWT validation was part of the between sites reproducibility study.
Seven positive samples were assayed by all three testing sites (including Inova). 85.7% (12 out of 14) of SWT results at the two external sites were within ± 1 dilution step of that of the manual titer, and 92.9% (13 out of 14) were within ± 1 dilution step of that of the digital titer; 100% of SWT results were within ± 2 dilution steps of that of both the manual titer and digital titer.
§ 866.5660 Multiple autoantibodies immunological test system.
(a)
Identification. A multiple autoantibodies immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the autoantibodies (antibodies produced against the body's own tissues) in serum and other body fluids. Measurement of multiple autoantibodies aids in the diagnosis of autoimmune disorders (disease produced when the body's own tissues are injured by autoantibodies).(b)
Classification. Class II (performance standards).