(541 days)
Not Found
No
The summary describes a standard immunoassay system with image capture and data processing for calculating results based on predefined curves and calibrators. There is no mention of AI or ML algorithms being used for image analysis, result interpretation, or any other function.
No
The device is an in-vitro diagnostic immunoassay system used to detect autoantibodies for the diagnosis of celiac disease and dermatitis herpetiformis. It does not provide any therapy or treatment.
Yes
The document states that the Aptiva Celiac Disease IgA Reagent, when used in conjunction with clinical findings and other laboratory tests, "is an aid in the diagnosis of celiac disease and dermatitis herpetiformis." This explicitly indicates a diagnostic purpose.
No
The device description explicitly states that the Aptiva instrument includes "liquid handling hardware, optical module (OM), and integrated computer with proprietary software and touch screen user interface." This indicates the device is a system that includes both hardware and software components, not software only.
Based on the provided information, the Aptiva Celiac Disease IgA Reagent and the Aptiva System are indeed IVDs (In Vitro Diagnostics).
Here's why:
- Intended Use/Indications for Use: The document explicitly states the intended use is for the "semiquantitative determination of anti-tissue transglutaminase IgA autoantibodies and anti-deamidated gliadin peptide IgA autoantibodies in human serum." It also states that the presence of these autoantibodies is "an aid in the diagnosis of celiac disease and dermatitis herpetiformis." This clearly indicates the device is intended for use on biological specimens (human serum) outside of the body to provide information for diagnostic purposes.
- Device Description: The description details a system that processes "clinical specimens" and performs "in vitro diagnostic testing." It describes the use of reagents and an automated analyzer to measure analytes in serum samples.
- Aptiva System Description: The description of the Aptiva System explicitly states it is an "automated particle-based multi-analyzer for in vitro diagnostic testing of clinical specimens."
These points align directly with the definition of an In Vitro Diagnostic device, which is a medical device intended for use in vitro for the examination of specimens, including blood and tissue samples, derived from the human body, solely or principally for the purpose of providing information concerning a physiological or pathological state, or a congenital abnormality, or to determine the compatibility of transplant tissues, organs or blood, or to monitor therapeutic measures.
N/A
Intended Use / Indications for Use
The Aptiva Celiac Disease IgA Reagent is an immunoassay utilizing particle-based multi-analyte technology for the semiquantitative determination of anti-tissue transglutaminase IgA autoantibodies and anti-deamidated gliadin peptide IgA autoantibodies in human serum. The presence of these autoantibodies, in conjunction with clinical findings and other laboratory tests, is an aid in the diagnosis of celiac disease and dermatitis herpetiformis. The Aptiva Celiac Disease IgA Reagent is intended for use with the Inova Diagnostics Aptiva System.
Aptiva System is an automated particle-based multi-analyzer for in vitro diagnostic testing of clinical specimens. The system is based on digital capture of high-resolution images of the paramagnetic particles to determine the analytes in samples.
Product codes (comma separated list FDA assigned to the subject device)
MST, MVM, NSU
Device Description
The Aptiva Celiac Disease IgA reagent utilizes particle based multi-analyte technology (PMAT) in a cartridge format. Each analyte (tissue transglutaminase [tTG] and deamidated gliadin peptide [DGP]) in the Aptiva Celiac Disease IgA reagent is a solid phase immunoassay utilizing fluorescent microparticles. This technology allows each of the two analytes, along with a human IgA capture antibody (IgA Control Microparticle), to be coated onto three uniquely recognizable paramagnetic microparticles, which are combined into one tube.
The Aptiva instrument is a fully automated, random access analyzer. This platform is a closed system with continuous load and random-access capabilities that processes the samples, runs the reagent and reports results. It includes liquid handling hardware, optical module (OM), and integrated computer with proprietary software and touch screen user interface.
The two analyte microparticles, along with the control microparticle, are stored in the reagent cartridge under conditions that preserve the proteins in their reactive states. When the assay cartridge is ready to be used for the first time, the reagent tube seals are pierced using the cartridge lid. The reagent cartridge is then loaded onto the Aptiva instrument, where the microparticles are automatically rehydrated using buffer located within the cartridge.
A patient's serum is diluted 1:46 with Aptiva system rinse by the instrument in a disposable cuvette. A small amount of the diluted sample is combined with assay buffer and the microparticle suspension in a second cuvette, and mixed (final serum dilution: 1:230). This reaction cuvette is incubated for 9 ½ minutes at 37°C. The cuvette is then exposed to a small magnet that holds the microparticles in place. The liquid is aspirated, and the microparticles are resuspended as system rinse is added to the cuvette and the magnet is removed. This wash cycle is repeated one more time. During the third wash, no system rinse is added after the aspiration step. After the third wash, phycoerythrin conjugated polyclonal anti-human IgA (known as PE Tracer IgA) is added to the microparticles in the cuvette, and mixed. Again, the cuvette is incubated for 9 ½ minutes at 37℃. Three wash steps, as described above, are performed on the microparticles. Following the wash steps, the microparticles are transferred to the of the instrument, where a charge coupled device (CCD) camera takes multiple images in order to identify and count the three unique microparticle regions, as well as determine the amount of conjugate on the microparticles. A third particle, coated with goat antibodies, is present in the reagent as a control to flag low concentrations of IgA in the sample as an assay verification step. The median fluorescent intensity (MFI) is proportional to the amount of PE Tracer that is bound to the human IgA, which is proportional to the amount of IgA antibodies bound to the corresponding microparticle regions.
For quantitation, the DGP IgA and tTG IgA assays (together as part of the Aptiva Celiac Disease IgA Reagent) each utilizes a predefined lot specific Master Curve that is uploaded onto the instrument through the reagent cartridge RFID tag. Every new lot of reagent cartridge must be calibrated before first use with the reagent specific calibrators. Based on the results obtained with the calibrators included in the Aptiva Celiac Disease IgA Calibrator kit (sold separately), an instrument specific Working Curve is created for each assay, which is used to calculate reported fluorescent light units (FLU) from the median fluorescent intensity (MFI) instrument signal obtained for each sample, on each of the two assays within the reagent.
Aptiva Celiac Disease IgA Calibrators and Aptiva Celiac Disease IgA Controls are sold separately.
The Aptiva Celiac Disease IgA Reagent kit contains the following materials:
One (1) Aptiva Celiac Disease IgA Reagent Cartridge, containing the following reagents for 250 determinations:
- a. Aptiva Celiac IgA microparticle containing 3 unique microparticle regions coated with recombinant tissue transglutaminase, deamidated gliadin peptide, or goat anti-human IgA antibody.
- b. Assay buffer - colored pink, containing protein stabilizers and preservatives.
- c. PE Tracer IgA phycoerythrin (PE) labeled anti-human IgA antibody, containing buffer, protein stabilizers and preservative.
- d. Rehydration Buffer - containing protein stabilizers and preservatives.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not Found
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Not Found
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Precision:
The precision of the Aptiva Celiac Disease IgA reagent was evaluated on 9 samples for DGP IgA and 10 samples for tTG IgA, containing various concentrations of antibodies in accordance with CLSI EPO5-A3, Evaluation of Precision of Quantitative Measurement Procedures; Approved Guideline. Samples were run in duplicates, twice a day, for 20 days. Data were analyzed with the Analyse-it for Excel method evaluation software, and repeatability (within-run), between run, between day and within-laboratory precision) were calculated. Acceptance criteria: Total %CV:
§ 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).
0
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June 16, 2021
Inova Diagnostics, Inc. Ronda Elliott VP, Quality Systems and Regulatory Affairs 9900 Old Grove Road San Diego, California 92131
Re: K193604
Trade/Device Name: Aptiva Celiac Disease IgA Reagent Regulation Number: 21 CFR 866.5750 Regulation Name: Radioallergosorbent (RAST) immunological test system Regulatory Class: Class II Product Code: MST. MVM. NSU Dated: October 20, 2020 Received: October 21, 2020
Dear Ronda Elliott:
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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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
1
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 Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
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 https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Ying Mao for Chief Division of Immunology and Hematology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
2
Indications for Use
510(k) Number (if known) K193604
Device Name Aptiva Celiac Disease IgA Reagent
Indications for Use (Describe)
The Aptiva Celiac Disease IgA Reagent is an immunoassay utilizing particle-based multi-analyte technology for the semiquantitative determination of anti-tissue transglutaminase IgA autoantibodies and anti-deamidated gliadin peptide IgA autoantibodies in human serum. The presence of these autoantibodies, in conjunction with clinical findings and other laboratory tests, is an aid in the diagnosis of celiac disease and dermatitis herpetiformis. The Aptiva Celiac Disease IgA Reagent is intended for use with the Inova Diagnostics Aptiva System.
Aptiva System is an automated particle-based multi-analyzer for in vitro diagnostic testing of clinical specimens. The system is based on digital capture of high-resolution images of the paramagnetic particles to determine the analytes in samples.
| Type of Use (Select one or both, as applicable) |
|---|
| ------------------------------------------------- |
X Prescription Use (Part 21 CFR 801 Subpart D)
Over-The-Counter Use (21 CFR 801 Subpart C)
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3
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510(k) Summary
Page 1 of 19
Aptiva Celiac Disease IgA Reagent
4
Page 2 of 19
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.
| Administrative data | ||
|---|---|---|
| Submitter: | Inova Diagnostics, Inc | |
| 9900 Old Grove Road, | ||
| San Diego, CA, 92131 | ||
| Purpose of submission: | New device | |
| Device in the submission: | Aptiva Celiac Disease IgA Reagent | |
| Revision Date: | June 4, 2021 | |
| Scientific contact: | Andrea Seaman, Manager, Research and Development | |
| Inova Diagnostics, Inc. | ||
| 9900 Old Grove Road, San Diego, CA, 92131 | ||
| Phone: 858-586-9900 x1395 | ||
| Fax: 858-863-0025 | ||
| Email: aseaman@inovadx.com | ||
| Quality Systems contact: | Ronda Elliott, VP, Quality Systems and RA | |
| Inova Diagnostics, Inc | ||
| 9900 Old Grove Road, San Diego, CA, 92131 | ||
| Phone: 858-586-9900 x1381 | ||
| Fax: 858-863-0025 | ||
| Email: relliott@inovadx.com | ||
| Device name (kit): | Proprietary name: | Aptiva Celiac Disease IgA Reagent |
| Common name: | anti-deamidated gliadin peptide (DGP) antibody | |
| immunoassay, anti-tissue transglutaminase | ||
| antibody immunoassay | ||
| Classification name: | DGP IgA: Radioallergosorbent (RAST) | |
| immunological test system | ||
| tTG IgA: Multiple autoantibodies immunological |
test system
5
| Regulation Medical Specialty | Immunology |
|---|---|
| Review Panel | Immunology |
| Product Code | DGP IgA: MST |
| tTG IgA: MVM | |
| Aptiva instrument: NSU | |
| Regulation Number | 866.5750, 866.5660, Aptiva instrument: 862.2570 |
| Device Class | 2 |
Predicate device
QUANTA Flash® DGP IgA, 510(k) number: K113863. Date of clearance: September 20, 2012. QUANTA Flash® h-tTG IgA, 510(k) number: K094060. Date of clearance: October 13, 2010.
Device description
The Aptiva Celiac Disease IgA reagent utilizes particle based multi-analyte technology (PMAT) in a cartridge format. Each analyte (tissue transglutaminase [tTG] and deamidated gliadin peptide [DGP]) in the Aptiva Celiac Disease IgA reagent is a solid phase immunoassay utilizing fluorescent microparticles. This technology allows each of the two analytes, along with a human IgA capture antibody (IgA Control Microparticle), to be coated onto three uniquely recognizable paramagnetic microparticles, which are combined into one tube.
The Aptiva instrument is a fully automated, random access analyzer. This platform is a closed system with continuous load and random-access capabilities that processes the samples, runs the reagent and reports results. It includes liquid handling hardware, optical module (OM), and integrated computer with proprietary software and touch screen user interface.
The two analyte microparticles, along with the control microparticle, are stored in the reagent cartridge under conditions that preserve the proteins in their reactive states. When the assay cartridge is ready to be used for the first time, the reagent tube seals are pierced using the cartridge lid. The reagent cartridge is then loaded onto the Aptiva instrument, where the microparticles are automatically rehydrated using buffer located within the cartridge.
A patient's serum is diluted 1:46 with Aptiva system rinse by the instrument in a disposable cuvette. A small amount of the diluted sample is combined with assay buffer and the microparticle suspension in a second cuvette, and mixed (final serum dilution: 1:230). This reaction cuvette is incubated for 9 ½ minutes at 37°C. The cuvette is then exposed to a small magnet that holds the microparticles in place. The liquid is aspirated, and the microparticles are resuspended as system rinse is added to the cuvette and the magnet is removed. This wash cycle is repeated one more time. During the third wash, no system rinse is added after the aspiration step. After the third wash, phycoerythrin conjugated polyclonal anti-human IgA (known as PE Tracer IgA) is added to the microparticles in the cuvette, and mixed. Again, the cuvette is incubated for 9 ½ minutes at 37℃. Three wash steps, as described above, are performed on the microparticles. Following the wash steps, the microparticles are transferred to the of the instrument, where a charge coupled device (CCD) camera takes multiple images in order to identify and
6
count the three unique microparticle regions, as well as determine the amount of conjugate on the microparticles. A third particle, coated with goat antibodies, is present in the reagent as a control to flag low concentrations of IgA in the sample as an assay verification step. The median fluorescent intensity (MFI) is proportional to the amount of PE Tracer that is bound to the human IgA, which is proportional to the amount of IgA antibodies bound to the corresponding microparticle regions.
For quantitation, the DGP IgA and tTG IgA assays (together as part of the Aptiva Celiac Disease IgA Reagent) each utilizes a predefined lot specific Master Curve that is uploaded onto the instrument through the reagent cartridge RFID tag. Every new lot of reagent cartridge must be calibrated before first use with the reagent specific calibrators. Based on the results obtained with the calibrators included in the Aptiva Celiac Disease IgA Calibrator kit (sold separately), an instrument specific Working Curve is created for each assay, which is used to calculate reported fluorescent light units (FLU) from the median fluorescent intensity (MFI) instrument signal obtained for each sample, on each of the two assays within the reagent.
Aptiva Celiac Disease IgA Calibrators and Aptiva Celiac Disease IgA Controls are sold separately.
The Aptiva Celiac Disease IgA Reagent kit contains the following materials:
One (1) Aptiva Celiac Disease IgA Reagent Cartridge, containing the following reagents for 250 determinations:
- a. Aptiva Celiac IgA microparticle containing 3 unique microparticle regions coated with recombinant tissue transglutaminase, deamidated gliadin peptide, or goat anti-human IgA antibody.
- b. Assay buffer - colored pink, containing protein stabilizers and preservatives.
- PE Tracer IgA phycoerythrin (PE) labeled anti-human IgA antibody, containing buffer, C. protein stabilizers and preservative.
- d. Rehydration Buffer - containing protein stabilizers and preservatives.
Intended use(s)
The Aptiva Celiac Disease IgA Reagent is an immunoassay utilizing particle-based multi-analyte technology for the semi-quantitative determination of anti-tissue transglutaminase IgA autoantibodies and antideamidated gliadin peptide IgA autoantibodies in human serum. The presence of these autoantibodies, in conjunction with clinical findings and other laboratory tests, is an aid in the diagnosis of celiac disease and dermatitis herpetiformis.
The Aptiva Celiac Disease IgA Reagent is intended for use with the Inova Diagnostics Aptiva System.
Indications for use
Same as intended use.
Substantial equivalence
The Aptiva Celiac Disease IgA Reagent has the same intended use and assay principle as the predicate devices.
7
Comparison to predicate device
Aptiva Celiac Disease IgA Reagent – DGP IgA Assay
| Similarities | ||
|---|---|---|
| Item | Aptiva Celiac Disease IgA Reagent (DGP IgA) | QUANTA Flash DGP IgA |
| Intended Use | The Aptiva Celiac Disease IgA Reagent is an immunoassay utilizing particle-based multi-analyte technology for the semi-quantitative determination of anti-tissue transglutaminase IgA autoantibodies and anti-deamidated gliadin peptide IgA autoantibodies in human serum. The presence of these autoantibodies, in conjunction with clinical findings and other laboratory tests, is an aid in the diagnosis of celiac disease and dermatitis herpetiformis. The Aptiva Celiac Disease IgA Reagent is intended for use with the Inova Diagnostics Aptiva System | The QUANTA Flash DGP IgA is a chemiluminescent immunoassay (CIA) for the semi-quantitative determination of IgA anti-deamidated gliadin peptide (DGP) antibodies in human serum. The presence of IgA anti-DGP antibodies, in conjunction with clinical findings and other laboratory tests, can aid in the diagnosis of the gluten sensitive enteropathies: celiac disease and dermatitis herpetiformis. |
| Assay Methodology | solid phase (heterogeneous) immunoassay | solid phase (heterogeneous) immunoassay |
| Antigen | deamidated gliadin peptide | deamidated gliadin peptide |
| Sample Type | human serum | human serum |
| Solid Phase | paramagnetic microparticles | paramagnetic microparticles |
| Differences | ||
| Item | Aptiva Celiac Disease IgA Reagent (DGP IgA) | QUANTA Flash DGP IgA |
| Detection/Operating Principle | fluorescent immunoassay | chemiluminescent immunoassay |
| Conjugate | phycoerythrin conjugated polyclonal anti-human IgA antibody | Isoluminol conjugated monoclonal anti-human IgA antibody |
| Units | fluorescent light units (FLU) | chemiluminescent units (CU) |
| Cut-off | 5 FLU | 20 CU |
| Similarities | ||
| Item | Aptiva Celiac Disease IgA Reagent | |
| (DGP IgA) | QUANTA Flash DGP IgA | |
| Analytical Measuring | ||
| Range | 0.72 FLU - 250.00 FLU | 5.2 CU - 2367.3 CU |
| Control | Controls have lot specific values assigned. | |
| Control 1 | ||
| DGP IgA - 6.65 FLU (4.65 – 8.64) | ||
| tTG IgA - 10.00 FLU (5.00-100.00) | ||
| Control 2 | ||
| DGP IgA - 13.65 FLU (9.56–17.75) | ||
| tTG IgA - 50.00 FLU (25.00 – 250.00) | Controls have lot specific values assigned. | |
| Negative Control | ||
| DGP IgA - 9.7 CU (5.8 – 13.6) | ||
| h-tTG IgA - 10.2 CU (6.1 – 14.3) | ||
| Positive Control | ||
| DGP IgA – 50.9 CU (30.5 – 71.3) | ||
| h-tTG IgA - 62.5 CU (37.5-87.5) | ||
| Calibration | Lot specific Master Curve + 3 | |
| calibrators (sold separately) | Lot specific Master Curve + 2 | |
| calibrators (sold separately) |
8
Aptiva Celiac Disease IgA Reagent – tTG IgA Assay
| Similarities | ||
|---|---|---|
| Item | Aptiva Celiac Disease IgA Reagent | |
| (tTG IgA) | QUANTA Flash tTG IgA | |
| Intended Use | The Aptiva Celiac Disease IgA Reagent is an immunoassay utilizing particle-based multi-analyte technology for the semi-quantitative determination of anti-tissue transglutaminase IgA autoantibodies and anti-deamidated gliadin peptide IgA autoantibodies in human serum. The presence of these autoantibodies, in conjunction with clinical findings and other laboratory tests, is an aid in the diagnosis of celiac disease and dermatitis herpetiformis. The Aptiva Celiac Disease IgA Reagent is intended for use with the Inova Diagnostics Aptiva System | The QUANTA Flash h-tTG IgA is a chemiluminescent immunoassay (CIA) for the semi-quantitative detection of IgA anti-human tissue transglutaminase (h-tTG) antibodies in human serum. The presence of IgA anti-h-tTG antibodies, in conjunction with clinical findings and other laboratory tests, can aid in the diagnosis of the gluten sensitive enteropathies celiac disease (CD) and dermatitis herpetiformis (DH). |
9
| Assay Methodology | solid phase (heterogeneous)
immunoassay | solid phase (heterogeneous)
immunoassay |
|-------------------|--------------------------------------------|--------------------------------------------|
| Antigen | recombinant tissue
transglutaminase | recombinant tissue
transglutaminase |
| Sample Type | human serum | human serum |
| Solid Phase | paramagnetic microparticles | paramagnetic microparticles |
10
| Differences | ||
|---|---|---|
| Item | Aptiva Celiac Disease IgA Reagent | |
| (tTG IgA) | QUANTA Flash tTG IgA | |
| Detection/Operating | ||
| Principle | fluorescent immunoassay | chemiluminescent immunoassay |
| Conjugate | Phycoerythrin conjugated | |
| polyclonal anti-human IgA | ||
| antibody | Isoluminol conjugated | |
| monoclonal anti-human IgA | ||
| antibody | ||
| Units | fluorescent light units (FLU) | chemiluminescent units (CU) |
| Cut-off | 5 FLU | 20 CU |
| Analytical Measuring | ||
| Range | 1.02 FLU - 600.00 FLU | 1.9 CU - 4965.5 CU |
| Calibration | Lot specific Master Curve + 3 | |
| calibrators (sold separately) | Lot specific Master Curve + 2 | |
| calibrators (sold separately) |
Analytical performance characteristics
Quantitation and units of measure
For quantitation, the Aptiva Celiac Disease IgA reagent utilizes predefined lot specific Master Curves, one for tTG IgA and one for DGP IgA that is uploaded onto the instrument through the reagent cartridge RFID. The analyte specific Master Curves are generated at Inova for each reagent lot, where in-house Master Curve Standards with assigned FLU values are run multiple times. The resulting MFI values generated are used to create a unique 4 parameter logistic (4PL) curve for each of the two analytes. The IgA control bead is present in the reagent as a control to flag low concentrations of IgA in the sample as an assay verification step. This microparticle also has an in-house standard which is run each time a new reagent lot is manufactured. The MFI produced by this standard is used as the cut-off threshold for the IgA control microparticle for that reagent lot. These four parameters of the analyte curves, as well as the MFI cut-off for the IgA control microparticle are embedded in the reagent cartridge RFID.
List of Aptiva Celiac Disease IgA Master Curve Standards - DGP IgA:
| Material | Assigned Value (FLU) |
|---|---|
| Celiac IgA Master Curve Standard 1 | 0.00 |
| Celiac IgA Master Curve Standard 2 | 4.81 |
| Celiac IgA Master Curve Standard 3 | 16.83 |
| Celiac IgA Master Curve Standard 4 | 58.89 |
| Celiac IgA Master Curve Standard 5 | 206.13 |
| Celiac IgA Master Curve Standard 6 | 721.45 |
11
| Material | Assigned Value (FLU) |
|---|---|
| Celiac IgA Master Curve Standard 1 | 0.00 |
| Celiac IgA Master Curve Standard 2 | 4.55 |
| Celiac IgA Master Curve Standard 3 | 15.93 |
| Celiac IgA Master Curve Standard 4 | 55.76 |
| Celiac IgA Master Curve Standard 5 | 194.90 |
| Celiac IgA Master Curve Standard 6 | 685.57 |
List of Aptiva Celiac Disease IgA Master Curve Standards – tTG IgA
IgA Control Microparticle Standard: 1 mg/dL human IgA
Precision
The precision of the Aptiva Celiac Disease IgA reagent was evaluated on 9 samples for DGP IgA and 10 samples for tTG IgA, containing various concentrations of antibodies in accordance with CLSI EPO5-A3, Evaluation of Precision of Quantitative Measurement Procedures; Approved Guideline. Samples were run in duplicates, twice a day, for 20 days.
Data were analyzed with the Analyse-it for Excel method evaluation software, and repeatability (withinrun), between run, between day and within-laboratory precision) were calculated. Results are summarized in the two tables below.
| Aptiva DGP IgA Precision | | Repeatability | | Between Run | | Between Day | | Within
Laboratory | | |
|--------------------------|-------------------|---------------|-------------|-------------|-------------|-------------|-------------|----------------------|-------------|------|
| Sample | Replicates
(N) | Mean
(FLU) | SD
(FLU) | CV | SD
(FLU) | CV | SD
(FLU) | CV | SD
(FLU) | CV |
| 1 | 80 | 2.02 | 0.08 | 3.8% | 0.03 | 1.5% | 0.08 | 3.9% | 0.11 | 5.7% |
| 2 | 80 | 3.75 | 0.09 | 2.3% | 0.22 | 5.9% | 0.20 | 5.2% | 0.31 | 8.2% |
| 3 | 80 | 4.53 | 0.16 | 3.4% | 0.20 | 4.4% | 0.20 | 4.4% | 0.32 | 7.1% |
| 4 | 80 | 5.41 | 0.23 | 4.2% | 0.24 | 4.4% | 0.20 | 3.7% | 0.38 | 7.1% |
| 5 | 80 | 6.53 | 0.15 | 2.3% | 0.34 | 5.2% | 0.36 | 5.5% | 0.52 | 7.9% |
| 6 | 80 | 12.42 | 0.34 | 2.7% | 0.33 | 2.7% | 0.77 | 6.2% | 0.90 | 7.3% |
| 7 | 80 | 34.03 | 0.98 | 2.9% | 2.54 | 7.5% | 1.77 | 5.2% | 3.25 | 9.5% |
| 8 | 80 | 153.51 | 3.70 | 2.4% | 5.40 | 3.5% | 7.75 | 5.0% | 10.14 | 6.6% |
| 9 | 80 | 203.78 | 4.31 | 2.1% | 2.85 | 1.4% | 6.21 | 3.0% | 8.08 | 4.0% |
Acceptance criteria: Total %CV: 250.00 FLU for DGP IgA or a result >600.00 FLU for tTG lgA after performing an additional 10-fold dilution, thereby bringing the measured value within the AMR. The reported result will be calculated by the software factoring the additional dilution. As the highest value that can be measured is 2500.00 FLU or 6000.00 FLU for DGP IgA or tTG IgA, respectively.
High concentration hook effect
To assess hook effect, 4 samples for DGP IgA and 7 samples for tTG IgA were tested at three increasing 2fold serial dilutions from the standard 1:46 dilution used by the Aptiva Celiac Disease IgA Reagent. All FLU values above the analytical measuring ranges of the two assays are theoretical and were mathematically calculated using the 4 parameters of their respective calibration curves. All samples showed increase in FLU values as dilution factor became more concentrated, thereby confirming that high positive specimens above the AMR do not show hook effect up to 1229.19 FLU for the DGP IgA assay and 1746.20 FLU for the tTG IgA assay (theoretical values calculated) in the Aptiva Celiac Disease IgA Reagent.
Linearity
The Linearity of the AMR was calculated separately for DGP IgA as part of the Aptiva Celiac Disease IgA Reagent.
The linearity of the AMR of DGP IgA and tTG IgA was evaluated by a study according to CLSI EPO6-A, Evaluation of the Linearity of Quantitative Measurement Procedures: A Statistical Approved Guideline. Four human serum samples for each assay with various antibody concentrations were serially diluted to obtain values that cover the entire AMR. The dilutions were assayed in duplicates. Results were analyzed according to the guideline performing regression analysis and identifying the best fitting polynomial.
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Acceptance criteria:
- Best fitting polynomial is a linear one, otherwise, the difference between the best-fitting nonlinear and linear polynomial is less than 15% or ±0.75 FLU for low level samples (allowable nonlinearity).
For DGP IgA, the best fitting polynomial found for samples 1 and 4 was a linear one, while third order polynomial was found for sample 2 and second order polynomial for sample 3. All acceptance criteria were fulfilled.
| Sample | Test Range
(FLU) | Slope
(95% CI) | Y-Intercept
(95% CI) | R² | Average % Recovery |
|----------|---------------------|------------------------|--------------------------|------|--------------------|
| 1 | 59.39 - 296.96 | 0.98
(0.94 to 1.02) | 10.65
(2.20 to 19.10) | 0.99 | 105.9% |
| 2 | 19.28 - 192.82 | 0.98
(0.96 to 1.00) | 2.72
(0.44 to 5.00) | 1.00 | 101.5% |
| 3 | 3.27 - 29.02 | 1.00
(0.96 to 1.04) | 0.61
(-0.12 to 1.34) | 0.99 | 104.1% |
| 4 | 0.48 - 4.79 | 0.94
(0.88 to 0.99) | 0.11
(-0.05 to 0.26) | 0.99 | 100.0% |
| Combined | 0.48 - 296.96 | 1.02
(1.01 to 1.03) | 0.61
(-0.69 to 1.92) | 1.00 | 102.9% |
For tTG IgA, the best fitting polynomial found for all samples was a linear one. All acceptance criteria were fulfilled.
| Sample | Test Range
(FLU) | Slope
(95% CI) | Y-Intercept
(95% CI) | R² | Average % Recovery |
|----------|---------------------|---------------------|----------------------------|------|--------------------|
| 1 | 69.43 - 694.33 | 1.04 (1.00 to 1.08) | -17.18
(-34.97 to 0.60) | 0.99 | 96.7% |
| 2 | 10.28 - 102.79 | 1.01 (0.97 to 1.04) | 1.12
(-1.06 to 3.30) | 1.00 | 102.9% |
| 3 | 1.98 - 19.80 | 0.94 (0.87 to 1.01) | -0.58
(-1.38 to 0.23) | 0.98 | 87.2% |
| 4 | 0.78 - 7.76 | 1.06 (0.98 to 1.14) | 0.27
(-0.10 to 0.65) | 0.98 | 113.2% |
| Combined | 0.78 - 694.33 | 1.01 (1.00 to 1.02) | -1.13
(-3.58 to 1.32) | 1.00 | 100.0% |
These data demonstrate the linearity of the analytical measuring range (0.72 FLU – 250.00 FLU) of the DGP IgA assay and the analytical measuring range (1.02 FLU - 600.00 FLU) of the tTG IgA assay, both as part of the Aptiva Celiac Disease IgA Reagent.
Interference
The interference study was performed according to CLSI EPO7-A2, Interference Testing in Clinical Chemistry; Approved Guideline - Second Edition. A set of three human serum specimens, one positive, one near the cutoff and one negative sample were tested using interfering substances (bilirubin, hemoglobin, triglycerides, cholesterol, rheumatoid factor IgM and human IgG). All interferents were spiked into every serum specimen and the resulting samples were assessed in triplicates with the Aptiva Celiac Disease IgA assays. Recovery of the unit values was calculated compared to control samples.
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Acceptance criteria for the interference studies were 85% - 115% recovery, or ± 15% of the cut-off (±0.75 FLU) difference, whichever is greater.
No interference was detected for DGP or tTG IgA with bilirubin up to 1 mg/mL (recovery: from 96.4%-101.5% and from 96.2% to 99.7% for DGP IgA and tTG IgA respectively), hemoglobin up to 2 mg/mL (recovery: from 102.7% to 108.4% and from 100.4% to 111.8% for DGP IgA and tTG IgA respectively), triglycerides up to 1000 mg/dL (recovery: from 102.6% to 107.7% and from 98.2% to 110.3% for DGP IgA and tTG IgA respectively), cholesterol up to 332.5 mg/dL (recovery: from 102.4% to 103.9% or -0.43 FLU and from 99.6% to 109.5% or -0.44 FLU for DGP IgA and tTG IgA respectively), RF IgM up to 250 IU/mL (recovery: 93.1% to 99.2% or 0.30 FLU and 98.8% to 102.6% or 0.35 FLU for DGP IgA and TTG IgA, respectively) and human IgG up to 70 mg/mL (recovery: from 99.8% to 102.3% or -0.36 FLU and from 99.5 to 102.4% or 0.32 FLU for DGP IgA and tTG IgA, respectively).
Sample Stability and Handling
For the DGP IgA assay, eight test samples were tested and for tTG IgA assay six test samples were tested. The samples used for this study were achieved by combining high and low antibody level to yield their desired reactivity. Test samples covered the analytical measuring ranges of each analyte. All samples were tested in duplicates for up to 21 days while stored at 2-8℃, up to 48 hours while stored at room temperature, and after repeated freeze/thaw cycles up to 5 cycles. Results were compared to those obtained on control samples (time zero / zero cycles).
Acceptance criteria: percent recovery is between 85-115% for positive samples, and between 80-120% for negative samples (