(40 days)
The Sigma Diagnostics INFINITY™ Uric Acid Reagent is intended for the in vitro quantitative, diagnostic determination of uric acid in human serum, plasma or urine on both automated and manual systems.
The Sigma Diagnostics INFINJTY™ Uric Acid Reagent is a device intended to measure uric acid in serum, plasma or urine. Measurements obtained by the device are used in the diagnosis and treatment of numerous renal and metabolic disorders, including renal failure, gout, leukemia, psoriasis, starvation or other wasting conditions, and of patients receiving cytotoxic drugs.
This reagent is based upon the methods of Trivedi and Kabasakalland with a modified Trinder peroxide assay using 2,4,6-Tribromo-3-hydroxy benzoic acid (TBHB).
The series of reactions involved in the assay system is as follows:
-
Uric Acid is oxidized to allantoin by uricase with the production of H2O2. 1 .
Uric Acid + O2 + H2O _ Uricase _ Allantoin + CO2 + H2O2 -
The peroxide reacts with 4-aminoantipyrine (4-AAP) and TBHB in the presence of 2. peroxidase to yield a quinoneimine dye. The resulting change in absorbance at 520 nm (500-550 nm) is proportional to uric acid concentration in the sample.
HoOs + 4-AAP + TBHB Peroxidase \ Ouinoneimine + H2O
Here's a breakdown of the acceptance criteria and study information for the Sigma Diagnostics INFINITY™ Uric Acid Reagent, Procedure 684, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Metric/Criterion | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Substantial Equivalence | The device should be substantially equivalent to a legally marketed predicate device. | The device is stated to be substantially equivalent to, and the same product as, the TRACE Scientific Uric Acid Reagent kit (K971485). |
| Correlation with Predicate Device (Sigma Diagnostics Uric Acid Reagent, Procedure No. 685) | Implied to show a strong linear relationship. | INFINITY Uric Acid = 0.96 (Uric Acid 685) + 0.23 |
| Correlation Sample Size (N) | Not explicitly stated, but typically a sufficient number of samples for regression analysis. | N = 126 |
| Sample Type for Correlation | Not explicitly stated as an acceptance criterion, but plasma samples were used. | Plasma samples |
Note: For an in vitro diagnostic (IVD) like this, specific analytical performance characteristics (e.g., precision, accuracy, linearity, lower limit of detection, upper limit of quantitation, interference) would typically be detailed in the full 510(k) submission but are not explicitly presented as acceptance criteria or reported performance values in this summary. The submitted information focuses on substantial equivalence to a predicate.
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: 126 samples were used for the correlation study.
- Data Provenance: The document does not specify the country of origin of the data. It also does not explicitly state whether the data was retrospective or prospective. Given the nature of a correlation study comparing a new reagent to an existing one, it's generally conducted prospectively using fresh or banked clinical samples. The use of "plasma samples" suggests human biological samples.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not applicable and not provided in the document.
For an IVD like a uric acid reagent, the "ground truth" for the test set is established by the reference method (the predicate device, in this case, Sigma Diagnostics Uric Acid Reagent, Procedure No. 685). The accuracy of the predicate device is assumed based on its prior clearance and validation. Clinical experts are not typically involved in establishing the "ground truth" for individual quantitative measurements in such a direct comparison study; instead, the existing, validated method serves as the comparator.
4. Adjudication Method for the Test Set
This information is not applicable and not provided in the document.
Adjudication methods (like 2+1, 3+1) are typically used in studies involving subjective interpretations (e.g., image-based diagnosis) where multiple human readers assess cases and a consensus or tie-breaking mechanism is needed to establish ground truth. For a quantitative chemical assay, the comparison is directly between the numerical results of two different analytical methods.
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
This information is not applicable and not provided in the document.
MRMC studies and the concept of "human readers improving with AI assistance" pertain to artificial intelligence (AI) systems designed to aid human interpretation, particularly in image analysis. This document describes a chemical reagent for quantitative laboratory measurement, not an AI-assisted diagnostic tool for subjective human interpretation.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
This information is not applicable and not provided in the document, as it describes a chemical reagent, not a software algorithm. The "device performance" refers to the analytical performance of the reagent system.
7. The Type of Ground Truth Used
The "ground truth" for the correlation study was the measurement of uric acid levels obtained by the predicate device, Sigma Diagnostics Uric Acid Reagent, Procedure No. 685 (K853357). This can be considered a form of reference method comparison or comparative measurement data.
8. The Sample Size for the Training Set
This information is not applicable and not provided in the document.
Chemical reagents like this do not typically have "training sets" in the sense of machine learning algorithms. Their performance characteristics are established through analytical validation studies (e.g., linearity, precision, accuracy, interference studies) and then compared to a predicate using clinical samples (the "test set" in this context). The formulation and optimization of the reagent itself would involve R&D, but not a "training set" of data in the AI sense.
9. How the Ground Truth for the Training Set Was Established
This information is not applicable and not provided in the document for the reasons stated in point 8.
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510(k) SUMMARY OF SAFETY AND EFFECTIVENESS
INFINITY™ Uric Acid Reagent, Procedure 684
Sigma Diagnostics INFINITY™ Uric Acid Reagent is intended for the in vitro quantitative, diagnostic determination of uric acid in human serum, plasma or urine on both automated and manual systems.
Uric acid is a metabolite of purines, nucleic acids and nucleoproteins. Consequently, abnormal levels may be indicative of a disorder in the metabolism of these substances. Hyperuricaemia may be observed in renal dysfunction, gout, leukemia, polycythaemia, atherosclerosis, diabetes, hypothyroidism, or in some genetic diseases. Decreased levels are present in patients with Wilson's Disease. 1-3
This reagent is based upon the methods of Trivedi and Kabasakalland with a modified Trinder peroxide assay using 2,4,6-Tribromo-3-hydroxy benzoic acid (TBHB).
The series of reactions involved in the assay system is as follows:
-
Uric Acid is oxidized to allantoin by uricase with the production of H2O2. 1 .
Uric Acid + O2 + H2O _ Uricase _ Allantoin + CO2 + H2O2 -
The peroxide reacts with 4-aminoantipyrine (4-AAP) and TBHB in the presence of 2. peroxidase to yield a quinoneimine dye. The resulting change in absorbance at 520 nm (500-550 nm) is proportional to uric acid concentration in the sample.
HoOs + 4-AAP + TBHB Peroxidase \ Ouinoneimine + H2O
The Sigma Diagnostics INFINITY™ Uric Acid Reagent (Procedure No. 684) is substantially equivalent to, and is the same product as the TRACE Scientific Uric Acid Reagent kit cleared by the FDA as K971485.
Correlation studies to Sigma Diagnostics Uric Acid Reagent, Procedure No. 685 (K853357) using plasma samples vielded a regression equation of:
INFINITY Uric Acid = 0.96 (Uric Acid 685) + 0.23 (N=126)
References
-
- Searcy RL: Diagnostic Biochemistry. McGraw-Hill, New York, NY, 1969
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- Henry RJ, Common C, Winkelman JW (eds), Clinical Chemistry: Principles and Techniques. Harper & Row, Hagerstown, MD, 1974
-
- Balls ME: Adv Clin Chem 18:213, 1976
-
- Trivedi R, Berta E, Rebar L: Clin Chem, 22:1223, 1976
-
- Kabasakallan P, Kalliney S, Wescott A: Clin Chem, 19:522, 1973
- Trinder P: J Clin Pathol, 22:246, 1949 6.
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Image /page/1/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the top half of the circle. Inside the circle is a stylized image of an eagle or other bird-like figure with three lines representing its body or wings.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
SEP 2 8 1999
William R. Gilbert, Ph.D. Manager, Scientific Affairs Sigma Diagnostics® Clinical Technical Services 545 South Ewing Avenue St. Louis, Missouri 63103
Re: K992798
Trade Name: Infinity™ URIC ACID Reagent (Procedure No. 684) Regulatory Class: II Product Code: CDO Dated: August 16, 1999 Received: August 19, 1999
Dear Dr. Gilbert:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we 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). 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.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770) 488-7655.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification"(21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours,
Steven Butman
Steven I. Gutman, M.D, M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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510(k) Number (if known): K992718
Device Name: INFINITY™ Uric Acid Reagent
Indications For Use:
The Sigma Diagnostics INFINJTY™ Uric Acid Reagent is a device intended to measure uric acid in serum, plasma or urine. Measurements obtained by the device are used in the diagnosis and treatment of numerous renal and metabolic disorders, including renal failure, gout, leukemia, psoriasis, starvation or other wasting conditions, and of patients receiving cytotoxic drugs.
in Cooper
(Division Sign-Off)
Division of Clinical Laboratoi vices
510(k) Number 1992798
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use
(Per 21 CFR 801.109)
OR
Over-The-Counter Use __
§ 862.1775 Uric acid test system.
(a)
Identification. A uric acid test system is a device intended to measure uric acid in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of numerous renal and metabolic disorders, including renal failure, gout, leukemia, psoriasis, starvation or other wasting conditions, and of patients receiving cytotoxic drugs.(b)
Classification. Class I (general controls). The device, when it is solely intended for use as an acid reduction of ferric ion test, a phosphotungstate reduction test, a gasometric uricase test, an ultraviolet uricase test, or an oxygen rate uricase test, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9.