(90 days)
Not Found
No
The device description and performance studies focus on a turbidimetric immunoassay and standard statistical analysis of results, with no mention of AI or ML.
No
This device is an in vitro diagnostic assay used to measure fecal calprotectin, which aids in the diagnosis and differentiation of certain conditions. It does not directly provide therapy or treatment to a patient.
Yes
The "Intended Use / Indications for Use" section explicitly states that the device is an "in vitro diagnostic assay" intended to "aid in the diagnosis of inflammatory bowel disease (IBD)".
No
The device is an in vitro diagnostic assay that involves physical reagents and is performed on clinical chemistry analyzers, indicating it is a hardware-dependent system, not software-only.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The "Intended Use / Indications for Use" section explicitly states that the device is an "in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin... in human stool." This directly aligns with the definition of an IVD, which are tests performed on samples taken from the human body to detect diseases, conditions, or infections.
- Device Description: The description details a laboratory test (particle-enhanced turbidimetric immunoassay) performed on patient samples (stool extracts). This is characteristic of an IVD.
- Performance Studies: The document describes various performance studies (Precision, Linearity, Accuracy, Method Comparison, Clinical Sensitivity/Specificity) which are standard requirements for demonstrating the analytical and clinical performance of an IVD.
- Predicate Device: The mention of a "Predicate Device" (BÜHLMANN fCAL® ELISA) with a K number (K181012) indicates that this device is being compared to a previously cleared IVD by a regulatory body (likely the FDA in the US, given the K number format).
All of these points strongly support the classification of this device as an In Vitro Diagnostic.
N/A
Intended Use / Indications for Use
The BÜHLMANN fCAL turbo is an in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin, a neutrophilic protein that is a marker of intestinal mucosal inflammation, in human stool. The BÜHLMANN fCAL turbo aids in the diagnosis of inflammatory bowel disease (IBD), specifically Crohn's disease (CD) and ulcerative colitis (UC) and aids in the differentiation of IBD from irritable bowel syndrome (IBS) in conjunction with other laboratory and clinical findings.
Product codes (comma separated list FDA assigned to the subject device)
NXO
Device Description
The BÜHLMANN fCAL® turbo, a particle-enhanced turbidimetric immunoassay (PETIA), is performed using patient stool extracts collected without preservatives. Calprotectin within the sample extract mediates immunoparticle agglutination; sample turbidity is proportional to calprotectin concentration. The detected light absorbance allows quantification of calprotectin concentration via interpolation of an established calibration curve. The assay is validated for use on clinical chemistry analyzers such as the Roche cobas® c501/c502 platforms.
The BÜHLMANN fCAL® turbo Reagent Kit is to be used in conjunction with the BÜHLMANN fCAL® turbo Calibrator Kit and BÜHLMANN fCAL® turbo Control Kit, which are available separately.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Intestinal mucosal (via human stool sample)
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 (Single-Site Repeatability Study Results):
- Sample size: 80 for each of 8 samples (S01-S08)
- Key results:
- S01 (Mean 42.9 µg/g): Within-run %CV 8.3%, Within-laboratory %CV 9.1%
- S08 (Mean 5405.6 µg/g): Within-run %CV 0.7%, Within-laboratory %CV 1.4%
Precision (Multi-Site Reproducibility Study Results):
- Sample size: 75 for each of 8 samples (S01-S08)
- Key results:
- S01 (Mean 47.2 µg/g): Within-run %CV 7.6%, Total Precision %CV 9.1%
- S08 (Mean 5475.6 µg/g): Within-run %CV 1.3%, Total Precision %CV 3.2%
Precision (Lot-to-Lot Precision Study Results):
- Sample size: 75 for each of 8 samples (S1-S8)
- Key results:
- S1 (Mean 45.2 µg/g): Within-Run %CV 7.1%, Total Precision %CV 11.3%
- S8 (Mean 5303.1 µg/g): Within-Run %CV 1.8%, Total Precision %CV 3.6%
Extraction Reproducibility Study Results:
- Sample size: 80 for each of 10 samples (S1-S10)
- Key results:
- S1 (Mean 47.7 µg/g): Within-Run %CV 2.4%, Total Precision (Between-operator) %CV 7.2%
- S10 (Mean 3330.4 µg/g): Within-Run %CV 2.8%, Total Precision (Between-operator) %CV 4.5%
Linearity Study:
- Study procedures: Two dilution series, each using a stool specimen extract with concentration above and below the anticipated analytical measuring range, combined in various mixing ratios. Each dilution tested in 4 replicates.
- Key results:
- Linear regression for Run 1 (37.6 – 12,216.0 µg/g): R2 = 0.9983
- Linear regression for Run 2 (33.5 – 13,339.5 µg/g): R2 = 0.9984
- Supports claimed direct measuring range: 30 - 2000 ug/g
- Supports claimed measuring range with automatic dilution: 30 - 10,000 ug/g
High Dose Hook Effect:
- Key results: No high dose hook effect at theoretical concentrations up to 45,715 ug/g.
Accuracy/Recovery:
- Sample size: 7 samples
- Key results: Total recovery ranged from 93.6% to 102.0%.
Analytical Sensitivity:
- Key results:
- LoB = 16.7 µg/g
- LoD = 23.7 µg/g
- LoQ = 30 µg/g
Interfering Substances:
- Study procedures: Stool specimen extracts with calprotectin concentrations of 30 µg/g, 100 µg/g, 300 µg/g, and 550 µg/g.
- Key results: Various analytes, pharmaceuticals, nutritional supplements, and enteropathological microorganisms (E. coli, Salmonella, Klebsiella, Citrobacter, Shigella, Yersinia) did not interfere.
Method Comparison:
- Sample size: 248 clinical study samples tested, 220 had valid results within the linear measuring range for both assays.
- Comparison: BÜHLMANN fCAL® turbo vs. predicate device (BÜHLMANN fCAL® ELISA assay).
- Analysis: Passing-Bablok regression analysis.
- Key results:
- Slope (95% CI): 1.025 (0.990, 1.058)
- Intercept (µg/g) (95% CI): -4.5 (-8.7, 0.3)
- Correlation r: 0.972
Clinical Sensitivity/Specificity (IBD vs. IBS):
- Sample size: 265
- Borderline values considered Positive:
- Sensitivity = 91.1%; 95% C.I. (85.0%, 95.3%)
- Specificity = 76.2%; 95% C.I. (67.9%, 83.2%)
- PPV = 79.9%; 95% C.I. (72.7%, 85.9%)
- NPV = 89.2%; 95% C.I. (81.9%, 94.3%)
- Borderline values considered Negative:
- Sensitivity = 80.0%; 95% C.I. (72.3%, 86.4%)
- Specificity = 87.7%; 95% C.I. (80.8%, 92.8%)
- PPV = 87.1%; 95% C.I. (79.9%, 92.4%)
- NPV = 80.9%; 95% C.I. (73.4%, 87.0%)
Clinical Sensitivity/Specificity (IBD vs. non-IBD):
- Sample size: 337
- Borderline values considered Positive:
- Sensitivity = 91.1%; 95% C.I. (85.0%, 95.3%)
- Specificity = 74.3%; 95% C.I. (67.7%, 80.1%)
- PPV = 70.3%; 95% C.I. (62.9%, 76.9%)
- NPV = 92.6%; 95% C.I. (87.4%, 96.1%)
- Borderline values considered Negative:
- Sensitivity = 80.0%; 95% C.I. (72.3%, 86.4%)
- Specificity = 85.1%; 95% C.I. (79.5%, 89.8%)
- PPV = 78.3%; 95% C.I. (70.4%, 84.8%)
- NPV = 86.4%; 95% C.I. (80.9%, 90.9%)
Expected Values/Reference Range:
- Sample size: 141 apparently healthy normal adults (> 21 years of age) with no symptoms or signs of gastrointestinal disease.
- Key results:
- 160 µg/g: 17 subjects (12.1%)
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
Clinical Sensitivity/Specificity (IBD vs. IBS) - Borderline Values Considered Positive:
- Sensitivity = 91.1%; 95% C.I. (85.0%, 95.3%)
- Specificity = 76.2%; 95% C.I. (67.9%, 83.2%)
- PPV = 79.9%; 95% C.I. (72.7%, 85.9%)
- NPV = 89.2%; 95% C.I. (81.9%, 94.3%)
Clinical Sensitivity/Specificity (IBD vs. IBS) - Borderline Values Considered Negative:
- Sensitivity = 80.0%; 95% C.I. (72.3%, 86.4%)
- Specificity = 87.7%; 95% C.I. (80.8%, 92.8%)
- PPV = 87.1%; 95% C.I. (79.9%, 92.4%)
- NPV = 80.9%; 95% C.I. (73.4%, 87.0%)
Clinical Sensitivity/Specificity (IBD vs. non-IBD) - Borderline Values Considered Positive:
- Sensitivity = 91.1%; 95% C.I. (85.0%, 95.3%)
- Specificity = 74.3%; 95% C.I. (67.7%, 80.1%)
- PPV = 70.3%; 95% C.I. (62.9%, 76.9%)
- NPV = 92.6%; 95% C.I. (87.4%, 96.1%)
Clinical Sensitivity/Specificity (IBD vs. non-IBD) - Borderline Values Considered Negative:
- Sensitivity = 80.0%; 95% C.I. (72.3%, 86.4%)
- Specificity = 85.1%; 95% C.I. (79.5%, 89.8%)
- PPV = 78.3%; 95% C.I. (70.4%, 84.8%)
- NPV = 86.4%; 95% C.I. (80.9%, 90.9%)
Predicate Device(s)
BÜHLMANN fCAL® ELISA, K181012
Reference Device(s)
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information
Not Found
§ 866.5180 Fecal calprotectin immunological test system.
(a)
Identification. A fecal calprotectin immunological test system is anin vitro diagnostic device that consists of reagents used to quantitatively measure, by immunochemical techniques, fecal calprotectin in human stool specimens. The device is intended forin vitro diagnostic use as an aid in the diagnosis of inflammatory bowel diseases (IBD), specifically Crohn's disease and ulcerative colitis, and as an aid in differentiation of IBD from irritable bowel syndrome.(b)
Classification. Class II (special controls). The special control for these devices is FDA's guidance document entitled “Class II Special Controls Guidance Document: Fecal Calprotectin Immunological Test Systems.” For the availability of this guidance document, see § 866.1(e).
0
Image /page/0/Picture/0 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.
June 25, 2019
Roshana Ahmed President Quaras. LLC 2101 Camino Rey Fullerton, California 92833
Re: K190784
Trade/Device Name: BUHLMANN fCAL turbo Regulation Number: 21 CFR 866.5180 Regulation Name: Fecal calprotectin immunological test system Regulatory Class: Class II Product Code: NXO Dated: March 25, 2019 Received: March 27, 2019
Dear Roshana Ahmed:
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 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
1
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,
Doug Jeffery, Ph.D. Acting Deputy Division Director 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) K190784
Device Name BÜHLMANN fCAL turbo
Indications for Use (Describe)
The BÜHLMANN fCAL turbo is an in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin, a neutrophilic protein that is a marker of intestinal mucosal inflammation, in human stool. The BÜHLMANN fCAL turbo aids in the diagnosis of inflammatory bowel disease (IBD), specifically Crohn's disease (CD) and ulcerative colitis (UC) and aids in the differentiation of IBD from irritable bowel syndrome (IBS) in conjunction with other laboratory and clinical findings.
| 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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3
510(k) Summary
I. Submitter
BÜHLMANN Laboratories AG Baselstrasse 55 Schönenbuch CH-4124 Switzerland Phone: +41 61 487 12 50
Contact Person: Laura Zurbrügg Date Prepared: June 20, 2019
II. Device
| Device Proprietary Name: | BUHLMANN fCAL® turbo |
|---|---|
| Common or Usual Name: | Fecal calprotectin immunological test system |
| Classification Name: | Calprotectin, Fecal |
| Regulation Number: | 21 CFR 866.5180 |
| Product Code: | NXO |
| Device Classification: | II |
III. Predicate Device
Substantial equivalence is claimed to the following device:
- BÜHLMANN fCAL® ELISA, K181012, BÜHLMANN Laboratories AG
IV. Device Description
The BÜHLMANN fCAL® turbo, a particle-enhanced turbidimetric immunoassay (PETIA), is performed using patient stool extracts collected without preservatives. Calprotectin within the sample extract mediates immunoparticle agglutination; sample turbidity is proportional to calprotectin concentration. The detected light absorbance allows quantification of calprotectin concentration via interpolation of an established calibration curve. The assay is validated for use on clinical chemistry analyzers such as the Roche cobas® c501/c502 platforms.
The BÜHLMANN fCAL® turbo Reagent Kit is to be used in conjunction with the BÜHLMANN fCAL® turbo Calibrator Kit and BÜHLMANN fCAL® turbo Control Kit, which are available separately.
4
V. Indications for Use
The BÜHLMANN fCAL® turbo is an in vitro diagnostic assay intended for the quantitative measurement of fecal calprotectin, a neutrophilic protein that is a marker of intestinal mucosal inflammation, in human stool. The BÜHLMANN fCAL® turbo aids in the diagnosis of inflammatory bowel disease (IBD), specifically Crohn's disease (CD) and ulcerative colitis (UC) and aids in the differentiation of IBD from irritable bowel syndrome (IBS) in conjunction with other laboratory and clinical findings.
VI. Comparison of Technological Characteristics
The BÜHLMANN fCAL® turbo and the predicate device share the following characteristics:
- measurement of human fecal calprotectin in human stool;
- use of a quantitative platform;
- use of manual weighing extraction method for stool samples; and ●
- clinical decision thresholds. ●
The BÜHLMANN fCAL® turbo is technologically different from the predicate device as follows:
- assay method;
- use of an alternate, automated, detection method;
- use of polyclonal antibodies; and ●
- broader measuring range. ●
The tables below compare key technological features between the subject and predicate device.
Technological comparison
Comparison of Assay
| Similarities | ||
|---|---|---|
| BÜHLMANN fCAL® turbo | BÜHLMANN fCAL® ELISA | |
| (K181012) | ||
| Analyte | Human fecal calprotectin | |
| (MRP8/14) | Human fecal calprotectin | |
| (MRP8/14) | ||
| Assay format | Quantitative | Quantitative |
| Specimen type | Human stool | Human stool |
| Extraction | ||
| Method | Manual Weighing (1:50 dilution in | |
| Extraction Buffer) | Manual Weighing (1:50 dilution in | |
| Extraction Buffer) | ||
| Clinical Decision | ||
| Thresholds | Normal: 160 µg/g | Normal: 160 µg/g |
5
| Differences | ||
|---|---|---|
| BÜHLMANN fCAL® turbo | BÜHLMANN fCAL® ELISA | |
| (K181012) | ||
| Method | PETIA | ELISA |
| Automation | Automated | Not automated |
| Solid phase | Polystyrene nanoparticles (beads) | 96-well polystyrene microtiter plate |
| Detection method | Automated clinical chemistry | |
| analyzer read at 546 nm | Microtiter plate reader read at | |
| 450 nm | ||
| Analyte-specific | ||
| antibody | ||
| components | Polyclonal antibodies against | |
| human calprotectin coated on | ||
| polystyrene beads | Capture antibodies: monoclonal | |
| antibodies against human | ||
| calprotectin coated on microtiter | ||
| plates | ||
| Detection antibodies: monoclonal | ||
| antibodies against human | ||
| calprotectin conjugated to HRP | ||
| Measuring range | Direct measuring range: | |
| 30 – 2000 µg/g | ||
| Measuring range with automatic | ||
| dilution: 30 – 10,000 µg/g | 30 – 1800 µg/g |
Comparison of Calibrators
| BÜHLMANN fCAL® turbo | BÜHLMANN fCAL® ELISA | |
|---|---|---|
| Indications for | ||
| Use | The BÜHLMANN fCAL® turbo | |
| Calibrator Kit is intended for use | ||
| with the BÜHLMANN fCAL® | ||
| turbo Reagent Kit for the | ||
| determination of fecal calprotectin | ||
| levels in extracted stool samples. | ||
| Comprised of six (6) calibrators, | ||
| each calibrator establishes a point | ||
| of reference for the working curve | ||
| that is used to calculate test results | ||
| from patient samples. | N/A | |
| Method | BÜHLMANN fCAL® turbo | BÜHLMANN fCAL® ELISA |
| Analyte | Native human calprotectin | |
| Source: human granulocyte extract | Native human calprotectin | |
| Source: human serum | ||
| Calibrators | 6 levels: | |
| Target values: 0, 50, 200, 500, | ||
| 1000, 2000 µg/g | 5 levels: | |
| 4, 12, 40, 120, and 240 ng/mL | ||
| Conversion factor | N/A | 7.5 |
| Value assignment: | Calibrator values assigned using a | |
| value transfer protocol for each | ||
| calibrator lot. Values are indicated | ||
| in the QC datasheet. | Nominal values: | |
| 30 µg/g, 90 µg/g, 300 µg/g, 900 | ||
| µg/g, 1800 µg/g |
6
| BÜHLMANN fCAL® turbo | BÜHLMANN fCAL® ELISA | |
|---|---|---|
| Configuration | Available as a separate | |
| BÜHLMANN fCAL® turbo | ||
| Calibrator Kit. | Included within the BÜHLMANN | |
| fCAL® ELISA kit. |
Comparison of Controls
| BÜHLMANN fCAL® turbo | BÜHLMANN fCAL® ELISA | |
|---|---|---|
| Indications for | ||
| Use | The BÜHLMANN fCAL® turbo | |
| Control Kit, comprised of a high | ||
| and low control, is intended for use | ||
| with the BÜHLMANN fCAL® | ||
| turbo Reagent Kit, for quality | ||
| control, in the determination of | ||
| fecal calprotectin levels in extracted | ||
| stool samples. | N/A | |
| Method | BÜHLMANN fCAL® turbo | BÜHLMANN fCAL® ELISA |
| Analyte | Native human calprotectin | |
| Source: human granulocyte extract | Native human calprotectin | |
| Source: human serum | ||
| Levels | 2 (low and high) | 2 (low and high) |
| Physio-chemical | ||
| characteristics | Ready to use | Ready to use |
| Configuration | Available as a separate | |
| BÜHLMANN fCAL® turbo Control | ||
| Kit | Included within the BÜHLMANN | |
| fCAL® ELISA kit |
Discussion
As seen above, differences between the subject and predicate device include the assay and detection methods, antibodies, and reportable measuring range. These technological differences do not create new questions of safety and effectiveness and the differences are addressed by the performance studies identified below.
7
VII. Performance Data
A. Clinical Thresholds
| Calprotectin Concentration | Interpretation | Follow-Up |
|---|---|---|
| 160 µg/g | Elevated | Retest as appropriate |
B. Precision
Single-Site Repeatability Study Results:
| ID | Mean
[µg/g] | n | Within-run
(Repeatability) | | Between-
run | | Between-
day | | Within-
laboratory | |
|-----|----------------|----|-------------------------------|------|-----------------|------|-----------------|------|-----------------------|------|
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| S01 | 42.9 | 80 | 3.6 | 8.3% | 1.2 | 2.7% | 1.1 | 2.5% | 3.9 | 9.1% |
| S02 | 98.4 | 80 | 2.5 | 2.6% | 1.8 | 1.8% | 2.2 | 2.2% | 3.7 | 3.8% |
| S03 | 166.5 | 80 | 4.3 | 2.6% | 0.8 | 0.5% | 1.9 | 1.2% | 4.8 | 2.9% |
| S04 | 267.6 | 80 | 3.9 | 1.4% | 2.5 | 0.9% | 1.8 | 0.7% | 5.0 | 1.9% |
| S05 | 642.0 | 80 | 20.1 | 3.1% | 14.9 | 2.3% | 0.0 | 0.0% | 25.1 | 3.9% |
| S06 | 1414.2 | 80 | 19.6 | 1.4% | 11.1 | 0.8% | 3.5 | 0.2% | 22.8 | 1.6% |
| S07 | 3251.4 | 80 | 40.8 | 1.3% | 21.4 | 0.7% | 19.7 | 0.6% | 50.1 | 1.5% |
| S08 | 5405.6 | 80 | 40.2 | 0.7% | 56.6 | 1.0% | 34.5 | 0.6% | 77.5 | 1.4% |
Multi-Site Reproducibility Study Results:
| ID | Mean
[µg/g] | n | Within-run
(Repeatability) | | Between-
day | | Between-
site | | Total
Precision | |
|-----|----------------|----|-------------------------------|-----|-----------------|-----|------------------|-----|--------------------|-----|
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| S01 | 47.2 | 75 | 3.6 | 7.6 | 2.4 | 5.0 | 0.0 | 0.0 | 4.3 | 9.1 |
| S02 | 91.1 | 75 | 3.5 | 3.8 | 3.5 | 3.8 | 2.8 | 3.1 | 5.7 | 6.2 |
| S03 | 185.4 | 75 | 5.1 | 2.7 | 2.7 | 1.4 | 5.5 | 3.0 | 7.9 | 4.3 |
| S04 | 276.9 | 75 | 6.4 | 2.3 | 4.5 | 1.6 | 9.7 | 3.5 | 12.5 | 4.5 |
| S05 | 674.5 | 75 | 12.9 | 1.9 | 1.2 | 0.2 | 22.8 | 3.4 | 26.3 | 3.9 |
| S06 | 1519.6 | 75 | 25.3 | 1.7 | 17.8 | 1.2 | 62.3 | 4.1 | 69.6 | 4.6 |
| S07 | 3343.8 | 75 | 54.6 | 1.6 | 35.6 | 1.1 | 100.0 | 3.0 | 119.4 | 3.6 |
| S08 | 5475.6 | 75 | 72.1 | 1.3 | 35.8 | 0.7 | 154.2 | 2.8 | 173.9 | 3.2 |
8
| ID | Mean [µg/g] | n | Within-Run (Repeatability) | Between-Day | Between-Lot | Total Precision | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| SD | %CV | SD | %CV | SD | %CV | SD | %CV | |||
| S1 | 45.2 | 75 | 3.22 | 7.1% | 1.36 | 3.0% | 3.70 | 8.2% | 5.09 | 11.3% |
| S2 | 86.4 | 75 | 3.69 | 4.3% | 1.19 | 1.4% | 5.66 | 6.6% | 6.86 | 7.9% |
| S3 | 175.8 | 75 | 5.04 | 2.9% | 0.29 | 0.2% | 9.90 | 5.6% | 11.11 | 6.3% |
| S4 | 263.9 | 75 | 7.55 | 2.9% | 0.00 | 0.0% | 9.98 | 3.8% | 12.52 | 4.7% |
| S5 | 647.4 | 75 | 15.47 | 2.4% | 0.00 | 0.0% | 15.28 | 2.4% | 21.74 | 3.4% |
| S6 | 1460.7 | 75 | 33.66 | 2.3% | 11.64 | 0.8% | 41.01 | 2.8% | 54.32 | 3.7% |
| S7 | 3234.5 | 75 | 71.23 | 2.2% | 8.90 | 0.3% | 130.29 | 4.0% | 148.76 | 4.6% |
| S8 | 5303.1 | 75 | 97.42 | 1.8% | 11.18 | 0.2% | 163.87 | 3.1% | 190.97 | 3.6% |
Lot-to-Lot Precision Study Results:
Extraction Reproducibility Study Results:
| Sample | n | Mean
(µg/g) | SD
(µg/g) | %CV | Within-Run
(Repeatability) | | Between-
extraction | | Between-
day | | Between-
operator | | Total
Precision | |
|--------|----|----------------|--------------|-----|-------------------------------|------|------------------------|------|-----------------|-----|----------------------|------|--------------------|-----|
| | | | | | SD
(µg/g) | %CV | SD
(µg/g) | %CV | SD
(µg/g) | %CV | SD
(µg/g) | %CV | SD
(µg/g) | %CV |
| S1 | 80 | 47.7 | 2.8 | 5.9 | 1.1 | 2.4 | 0.7 | 1.5 | 1.4 | 2.9 | 3.4 | 7.2 | | |
| S2 | 80 | 72.3 | 3.8 | 5.2 | 3.9 | 5.4 | 4.2 | 5.8 | 0.0 | 0.0 | 6.8 | 9.5 | | |
| S3 | 80 | 96.1 | 3.8 | 3.9 | 2.2 | 2.3 | 1.4 | 1.4 | 0.0 | 0.0 | 4.6 | 4.8 | | |
| S4 | 80 | 170.6 | 4.0 | 2.4 | 2.5 | 1.5 | 8.7 | 5.1 | 0.0 | 0.0 | 9.9 | 5.8 | | |
| S5 | 80 | 277.0 | 3.7 | 1.4 | 27.9 | 10.1 | 10.0 | 3.6 | 11.0 | 4.0 | 31.8 | 11.5 | | |
| S6 | 80 | 421.1 | 9.8 | 2.3 | 5.9 | 1.4 | 15.3 | 3.6 | 0.0 | 0.0 | 19.1 | 4.5 | | |
| S7 | 80 | 573.9 | 5.4 | 0.9 | 39.5 | 6.9 | 0.0 | 0.0 | 0.0 | 0.0 | 39.9 | 6.9 | | |
| S8 | 80 | 1387.4 | 39.1 | 2.8 | 75.1 | 5.4 | 159.9 | 11.5 | 0.0 | 0.0 | 180.9 | 13.0 | | |
| S9 | 80 | 3264.9 | 87.2 | 2.7 | 236.2 | 7.2 | 256.9 | 7.9 | 0.0 | 0.0 | 359.7 | 11.0 | | |
| S10 | 80 | 3330.4 | 89.8 | 2.7 | 92.4 | 2.8 | 75.7 | 2.3 | 0.0 | 0.0 | 149.4 | 4.5 | | |
9
C. Linearity
Study procedures were performed using two dilution series. For each dilution series, a stool specimen extract with concentration above the anticipated upper limit of the analytical measuring range was combined with a stool specimen extract with concentration below the anticipated lower limit of the analytical measuring range, in various mixing ratios covering the range; each dilution was tested in 4 replicates. Results of the linear regression analyses are presented in the table below.
| Best | Measuring
Range [µg/g] | Linear regression parameters | | |
|------|---------------------------|------------------------------|-------------------------|--------|
| | | Intercept
(95% C.I.) | Slope
(95% C.I.) | R2 |
| 1 | 37.6 – 12,216.0 | 5.7
(1.6, 16.9) | 1.057
(1.044, 1.075) | 0.9983 |
| 2 | 33.5 – 13,339.5 | 3.8
(-0.4, 13.3) | 1.031
(1.014, 1.042) | 0.9984 |
The data supports the following claims for analytical measuring range:
Direct analytical measuring range: 30 - 2000 ug/g Measuring range with automatic dilution: 30 - 10,000 ug/g
D. High Dose Hook Effect
No high dose hook effect at theoretical concentrations up to 45,715 ug/g.
E. Accuracy/Recovery
| Sample No | 7226 | 7228 | 7238 | 7236 | 7244 | 7234 | 7246 |
|---|---|---|---|---|---|---|---|
| Baseline result [µg/g] | 44.10 | 65.45 | 116.43 | 138.48 | 230.88 | 510.78 | 1076.33 |
| Expected post-spike result [µg/g] | 101.04 | 122.39 | 173.37 | 195.42 | 458.65 | 738.55 | 1304.10 |
| Observed post-spike result [µg/g] | 94.55 | 114.53 | 170.23 | 186.93 | 453.10 | 753.18 | 1309.28 |
| Total recovery [%] | 93.6% | 93.6% | 98.2% | 95.7% | 98.8% | 102.0% | 100.4% |
F. Analytical Sensitivity
Results of the analytical sensitivity studies support a claimed direct measuring range of 30 -2000 ug/g and a measuring range of 30 - 10,000 µg/g with automatic dilution.
LoB = 16.7 µg/g LoD = 23.7 µg/g LoQ = 30 µg/g
10
G. Interfering Substances
Study procedures were performed using stool specimen extracts with the following approximate calprotectin concentrations: 30 µg/g, 100 µg/g, 300 µg/g, and 550 µg/g. The following analytes, pharmaceuticals, and nutritional supplements did not interfere with the BÜHLMANN fCAL® turbo:
| Trade name | Active component | Solvent | Concentration
mg/50 mg
stool |
|------------------|-------------------------|---------------------------------|------------------------------------|
| gyno-Tardyferon | Iron (II) sulfate | HCl/NaOH | 0.11 |
| Prednisone | Prednisone | DMSO | 0.31 |
| Imurek | Azathioprine | DMSO | 0.19 |
| Salofalk | Mesalamine; 5-ASA | DMSO | 5.21 |
| Agopton | Lansoprazole | Dimethylformamide | 0.18 |
| Asacol | Mesalamine; 5-ASA | DMSO | 2.50 |
| Vancocin | Vancomycin | H2Odd | 2.00 |
| Sulfamethoxazole | Sulfamethoxazole | DMSO | 1.60 |
| Trimethoprim | Trimethoprim lactate | DMSO/Exbuffer | 0.35 |
| Ciproxine | Ciprofloxacin | solvent from manufacturer/H2Odd | 1.25 |
| Vitamin E | DL-α Tocopherol Acetate | H2O + Tween | 0.30 |
| Bion 3 | Multivitamin | HCl/NaOH | 1.06 |
| Hemoglobin | Hemoglobin | H2Odd | 1.25 |
The following enteropathological microorganisms did not interfere with the BÜHLMANN fCAL® turbo when added to stool extracts at the given cell counts:
| Microorganism | Concentration
(cfu/mL) |
|-----------------------------------------------|---------------------------|
| Escherichia coli | 3.3 x 107 |
| Salmonella enterica subsp. enterica | 9.0 x 107 |
| Klebsiella pneumoniae subsp. pneumonia | 5.3 x 107 |
| Citrobacter freundii | 12.9 x 107 |
| Shigella flexneri | 5.0 x 107 |
| Yersinia enterocolitica subsp. enterocolitica | 9.8 x 107 |
11
H. Method Comparison
A total of 248 clinical study samples were tested using the BÜHLMANN fCAL® turbo and the predicate device (BÜHLMANN fCAL® ELISA assay); valid results within the linear measuring range for both assays were obtained for 220 of these samples. Results were analyzed by Passing-Bablok regression analysis.
| Slope
(95% CI) | Intercept (µg/g)
(95% CI) | Bias at 80 µg/g
(95% CI) | Bias at 160 µg/g
(95% CI) | Correlation
r |
|-------------------|------------------------------|-----------------------------|------------------------------|-------------------------|
| 1.025 | -4.5 | -3.1% | -0.3% | 0.972 |
| (0.990, 1.058) | (-8.7, 0.3) | (-7.2%, 0.5%) | (-2.4%, 2.7%) | |
Frequency counts of BÜHLMANN fCAL® turbo test results and corresponding BÜHLMANN fCAL® ELISA assay results within each of the diagnostic ranges of these tests are provided below.
| # in BÜHLMANN fCAL® ELISA assay range (µg/g) | |||||
|---|---|---|---|---|---|
| 160 | Total | ||||
| # in fCAL | |||||
| turbo range | |||||
| (µg/g) | 160 | 0 | 7 | 92 | 99 |
| Total | 92 | 58 | 98 | 248 |
Estimates of positive percent agreement (PPA) and negative percent agreement (NPA) between the BÜHLMANN fCAL® turbo results and corresponding BÜHLMANN fCAL® ELISA assay results, using both sets of assay cutoffs, with respect to IBD subjects, other GI subjects, normal subjects, and all subjects combined are shown in the table below.
12
| Subgroup | Metric | Estimate | 95% C.I. |
|---|---|---|---|
| IBD | PPA (lower cutoff) | 68/70 = 97.1% | [90.1%, 99.7%] |
| NPA (lower cutoff) | 6/7 = 85.7% | [42.1%, 99.6%] | |
| PPA (upper cutoff) | 52/56 = 92.9% | [82.7%, 98.0%] | |
| NPA (upper cutoff) | 19/21 = 90.5% | [69.6%, 98.8%] | |
| IBS | PPA (lower cutoff) | 28/32 = 87.5% | [71.0%, 96.5%] |
| NPA (lower cutoff) | 31/33 = 93.9% | [79.8%, 99.3%] | |
| PPA (upper cutoff) | 12/13 = 92.3% | [64.0%, 99.8%] | |
| NPA (upper cutoff) | 49/52 = 94.2% | [84.1%, 98.8%] | |
| Other GI | PPA (lower cutoff) | 20/21 = 95.2% | [76.2%, 99.9%] |
| NPA (lower cutoff) | 16/16 = 100% | [79.4%, 100%] | |
| PPA (upper cutoff) | 13/14 = 92.9% | [66.1%, 99.8%] | |
| NPA (upper cutoff) | 23/23 = 100% | [85.2%, 100%] | |
| Normal | PPA (lower cutoff) | 30/33 = 90.9% | [75.7%, 98.1%] |
| NPA (lower cutoff) | 31/36 = 86.1% | [70.5%, 95.3%] | |
| PPA (upper cutoff) | 15/15 = 100% | [78.2%, 100%] | |
| NPA (upper cutoff) | 52/54 = 96.3% | [87.3%, 99.5%] | |
| All subjects | PPA (lower cutoff) | 146/156 = 93.6% | [88.5%, 96.9%] |
| NPA (lower cutoff) | 84/92 = 91.3% | [83.6%, 96.2%] | |
| PPA (upper cutoff) | 92/98 = 93.9% | [87.1%, 97.7%] | |
| NPA (upper cutoff) | 143/150 = 95.3% | [90.6%, 98.1%] |
I. Clinical Sensitivity/Specificity
IBD vs. IBS:
| Borderline Values
| Considered Positive | Clinical Diagnosis | Total | ||
|---|---|---|---|---|
| BÜHLMANN | ||||
| fCAL® turbo | IBD | IBS | ||
| BÜHLMANN | ||||
| fCAL® turbo | Positive | 123 | 31 | 154 |
| BÜHLMANN | ||||
| fCAL® turbo | Negative | 12 | 99 | 111 |
| Total | 135 | 130 | 265 | |
| Sensitivity = 91.1%; 95% C.I. (85.0%, 95.3%) | ||||
| Specificity = 76.2%; 95% C.I. (67.9%, 83.2%) | ||||
| PPV = 79.9%; 95% C.I. (72.7%, 85.9%) | ||||
| NPV = 89.2%; 95% C.I. (81.9%, 94.3%) |
13
| Borderline Values
| Considered Negative | Clinical Diagnosis | Total | ||
|---|---|---|---|---|
| IBD | IBS | |||
| BÜHLMANN | ||||
| fCAL® turbo | Positive | 108 | 16 | 124 |
| Negative | 27 | 114 | 141 | |
| Total | 135 | 130 | 265 | |
| Sensitivity = 80.0%; 95% C.I. (72.3%, 86.4%) | ||||
| Specificity = 87.7%; 95% C.I. (80.8%, 92.8%) | ||||
| PPV = 87.1%; 95% C.I. (79.9%, 92.4%) | ||||
| NPV =80.9%; 95% C.I. (73.4%, 87.0%) |
IBD vs. non-IBD:
| Borderline Values | Clinical Diagnosis | Total | |||
|---|---|---|---|---|---|
| Considered Positive | IBD | Non-IBD | |||
| BÜHLMANN | Positive | 123 | 52 | 175 | |
| fCAL® turbo | Negative | 12 | 150 | 162 | |
| Total | 135 | 202 | 337 | ||
| Sensitivity = 91.1%; 95% C.I. (85.0%, 95.3%) | |||||
| Specificity = 74.3%; 95% C.I. (67.7%, 80.1%) | |||||
| PPV = 70.3%; 95% C.I. (62.9%, 76.9%) | |||||
| NPV = 92.6%; 95% C.I. (87.4%, 96.1%) |
| Borderline Values | Clinical Diagnosis | Total | |||
|---|---|---|---|---|---|
| Considered Negative | IBD | IBS | |||
| BÜHLMANN | Positive | 108 | 30 | 138 | |
| fCAL® turbo | Negative | 27 | 172 | 199 | |
| Total | ા રેર | 202 | 337 | ||
| Sensitivity = 80.0%; 95% C.I. (72.3%, 86.4%) | |||||
| Specificity = 85.1%; 95% C.I. (79.5%, 89.8%) | |||||
| PPV = 78.3%; 95% C.I. (70.4%, 84.8%) | |||||
| NPV =86.4%; 95% C.I. (80.9%, 90.9%) |
14
J. Expected Values/Reference Range:
Stool samples were obtained from 141 apparently healthy normal adults (> 21 years of age) with no symptoms or signs of gastrointestinal disease. The test results were categorized by the assay cut-offs below.
| Calprotectin level by BÜHLMANN fCAL turbo | ||||
|---|---|---|---|---|
| 160 μg/g | Total | |||
| Number of | ||||
| subjects (%) | 106 (75.2%) | 18 (12.8%) | 17 (12.1%) | 141 (100%) |
VIII. Conclusion
The information provided above supports that the BÜHLMANN fCAL® turbo is as safe and effective as the predicate device. Although differences exist between the subject and predicate device, verification and validation studies support that these differences do not raise any new questions of safety and effectiveness. Therefore, it is concluded that the BÜHLMANN CAL® turbo is substantially equivalent to the predicate device.
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