(165 days)
The LEUKO EZ VUE™ test is an immunochromatographic test for the qualitative detection of elevated levels of fecal lactoferrin, a marker for fecal leukocytes and an indicator of intestinal inflammation. The LEUKO EZ VUE™ test detects lactoferrin in liquid, semi-solid, and solid fecal specimens. A positive test result indicates an increased level of fecal lactoferrin and warrants additional testing. FOR IN VITRO DIAGNOSTIC USE.
The LEUKO EZ VUE™ test is a 10 minute immunochromatographic device for the detection of elevated levels of lactoferrin, a marker for fecal leukocytes and an indicator of intestinal inflammation. The test utilizes the same polyclonal antibodies against human lactoferrin as our previously cleared LEUKO-TEST assay. The polyclonal antibodies to human lactoferrin are immobilized on nitrocellulose and the conjugate consists of the same antibodies linked to colloidal gold particles. The membrane cassette contains two stripes of immobilized antibodies. One stripe contains anti-lactoferrin antibodies. The other, representing a control stripe, contains anti-IgG antibodies. The diluted sample and gold conjugate migrate by capillary action when the sample is added to the well. If elevated lactoferrin is present in the sample, gold conjugate-lactoferrin complexes form and are captured by the immobilized anti-lactoferrin antibodies in the stripe. The lactoferrin-conjugate-antibody complexes appear as a single red line in the test portion of the Results window. In the control stripe, conjugate binds to the immobilized anti-IgG antibodies, demonstrating correct migration of the sample and conjugate along the membrane. The conjugate-anti-IgG antibodies appear as a single red line in the control portion of the Results window.
Here's a summary of the acceptance criteria and study details for the LEUKO EZ VUE™ device, based on the provided 510(k) summary:
Acceptance Criteria and Device Performance
The acceptance criteria for the LEUKO EZ VUE™ were based on its agreement with the predicate device, LEUKO-TEST.
| Acceptance Criteria | Reported Device Performance (%) | 95% Confidence Intervals |
|---|---|---|
| Percent Positive Agreement with LEUKO-TEST | 93% | 86 – 97% |
| Percent Negative Agreement with LEUKO-TEST | 80% | 74 – 84% |
| Overall Percent Agreement with LEUKO-TEST | 83% | 80 – 86% |
Study Information
This study evaluated the performance of the LEUKO EZ VUE™ test against the predicate LEUKO-TEST in clinical studies.
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Sample size used for the test set and the data provenance:
- Sample Size: 375 specimens
- Data Provenance: The document does not specify the country of origin. It indicates "clinical studies" without further detail on the nature (retrospective or prospective) of the data collection for these specific comparative studies.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- The "ground truth" for this study was established using the results of the LEUKO-TEST (K931241/A1), which is a previously cleared latex agglutination test. The document does not mention the use of experts to establish a separate ground truth or to interpret the LEUKO-TEST results for the purpose of this comparative study.
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Adjudication method for the test set:
- Not applicable. The study compares the LEUKO EZ VUE™ to the LEUKO-TEST directly, rather than against an expert-adjudicated ground truth.
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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:
- No, an MRMC comparative effectiveness study was not done. This device is a rapid in-vitro diagnostic test, not an AI-assisted diagnostic tool requiring human interpretation. The output is a visual presence of a red line.
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If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Yes, the LEUKO EZ VUE™ test's performance was evaluated as a standalone device by comparing its results directly to the LEUKO-TEST results. It is an immunochromatographic device that provides a visual reading ("red line in the test portion of the Results window").
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The type of ground truth used:
- The ground truth for comparison was the results obtained from the LEUKO-TEST (K931241/A1).
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The sample size for the training set:
- The document does not explicitly mention a "training set" or its size. As this is a performance comparison of an in-vitro diagnostic device against a predicate, typical machine learning training set paradigms are not directly applicable in the same way. The study focuses on evaluating the device's performance on a set of clinical samples.
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How the ground truth for the training set was established:
- Not applicable, as a distinct "training set" with established ground truth, in the context of machine learning, is not described for this type of IVD performance study. The performance evaluation samples were compared against the results of the predicate LEUKO-TEST.
§ 866.5570 Lactoferrin immunological test system.
(a)
Identification. A lactoferrin immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the lactoferrin (an iron-binding protein with the ability to inhibit the growth of bacteria) in serum, breast milk, other body fluids, and tissues. Measurement of lactoferrin may aid in the diagnosis of an inherited deficiency of this protein.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 866.9.