(294 days)
The Sofia Lyme FIA employs immunofluorescence for the rapid differential detection of human IgM and IgG antibodies to Borrelia burgdorferi from serum and plasma specimens from patients suspected of B. burgdorferi infection. This qualitative test is intended for use as an aid in the diagnosis of Lyme disease. A negative result does not preclude infection with B. burgdorferi. All positive results for IgM and/or IgG should be further tested by a corresponding second-tier western blot assay. Test results are to be used in conjunction with information obtained from the patient's clinical evaluation and other diagnostic procedures.
The Sofia Lyme Control Set is intended for use as assayed quality control materials to verify the performance of the Sofia Lyme FIA test system.
The Sofia Lyme FIA is an immunofluorescence-based, lateral flow assay for detection of IgM and/or IgG antibodies to Borrelia burgdorferi in patient specimens. Reagents for the assay are ready-to-use and provided in the kit.
The assay uses a bidirectional test strip format to detect both IgM and IgG antibodies to B. burgdorferi. One side of the test strip detects IgM antibodies to B. burgdorferi and the other side of the test strip detects IgG antibodies to B. burgdorferi.
To perform the test, the patient specimen (30 uL serum/plasma) is added to a pre-filled Reagent Vial. 100 uL of the diluted sample is then dispensed into the round sample well located near the center of the Test Cassette. The Test Cassette is loaded into Sofia for an automatically defined development time (WALK AWAY Mode) or pre-incubated on the bench top prior to loading into Sofia (READ NOW Mode). Sofia scans the test strip, analyzes the fluorescent signal, and then displays two (2) test results: IgM (positive, negative or invalid) and IgG (positive, negative or invalid). As an option, the results are automatically printed on the integrated printer.
Each Sofia Lyme FIA kit will contain one Positive and one Negative Control—each provided in separate dropper bottles. The external controls will be provided separately as well in a Sofia Lyme Control Set. The Positive and Negative QC controls are formulated with patient Lyme IgM and IgG positive serum that are diluted into 1X PBS and 0.3% Microcide is added to the solution as an antimicrobial. The External Controls will be tested by adding 2 drops to the test cassette.
The provided text describes the 510(k) summary for the Sofia Lyme FIA and Sofia Lyme Control Set, which employs immunofluorescence for the rapid differential detection of human IgM and IgG antibodies to Borrelia burgdorferi. The device is intended as an aid in the diagnosis of Lyme disease.
Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state numerical "acceptance criteria" for the performance studies in the format of a predefined threshold. Instead, it describes various studies undertaken and concludes that these studies "demonstrated the substantial equivalence" to the predicate devices (Vidas Lyme IgG and Vidas Lyme IgM) and that there was "good performance," "comparable performance," and "very good" specificity.
| Performance Characteristic | Acceptance Criteria (Implicit from "Conclusion" and study descriptions) | Reported Device Performance |
|---|---|---|
| Overall Performance | Demonstrate substantial equivalence to predicate devices (Vidas Lyme IgM and Vidas Lyme IgG) in terms of safety and effectiveness. | "These studies demonstrated the substantial equivalence of the Sofia Lyme FIA to the Vidas Lyme IgG and Vidas Lyme IgM tests. Such studies are a critical element in establishing the fundamental safety and effectiveness of the product and its appropriateness for commercial distribution." |
| Analytical Studies | Good performance in Limit of Detection, cross-reactivity, interfering substances, specimen handling, operating temperature, and various flex studies. | "All studies demonstrated good performance." |
| Precision | Total precision results for IgM and IgG not significantly different within-run, within-day, between day and total for various sample concentrations (negative, high negative, low positive, moderate positive). | "The total precision results for IgM and IgG were not significantly different within-run, within-day, between day and total when tested with the negative (C0), high negative (C5), low positive (C95) and moderate positive (2-3X LOD) samples." |
| CDC Reference Panel | Good overall agreement for Clinical Status of IgG and IgM samples between Sofia Lyme FIA and Western Blot. | "When testing the CDC reference panel, the overall agreement for Clinical Status of IgG and IgM samples between Sofia Lyme FIA and Western Blot was good." |
| Clinical Sensitivity | Comparable performance to a 510(k) cleared test for well-characterized clinically or culture-confirmed Lyme disease samples. | "The clinical sensitivity was compared to a 510(k) cleared test and the performance was comparable." |
| Clinical Specificity | Very good specificity using serum from asymptomatic (healthy, normal) populations in endemic and non-endemic regions. | "The overall specificity of the Sofia Lyme FIA was very good." |
| Method Comparison | Comparable performance to Vidas Lyme IgG and Vidas Lyme IgM tests when testing prospectively collected serum specimens from subjects suspected of Lyme disease. | "This study demonstrated that Sofia Lyme FIA has comparable performance to the Vidas Lyme IgG and Vidas Lyme IgM tests when testing prospectively collected serum specimens from subjects suspected of having Lyme disease." |
| Reproducibility | Accurate results obtained by operators across laboratories with a panel of test samples at various concentrations. | "The operators and laboratories obtained accurate results with the Sofia Lyme FIA." |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the exact sample sizes for each test set in the "Performance Data" section.
- For the Clinical Sensitivity Study, it used "well-characterized clinically or culture confirmed Lyme disease samples."
- For the Specificity Study, it used "serum obtained from asymptomatic (healthy, normal) populations in both endemic and non-endemic regions."
- For the Method Comparison, it used "prospectively collected serum specimens from subjects suspected of having Lyme disease."
The provenance of the data (country of origin, retrospective/prospective) is partially mentioned:
- The Specificity Study included data from both endemic and non-endemic regions, suggesting a diverse geographical origin for these samples.
- The Method Comparison study used "prospectively collected serum specimens." No explicit mention of the country(ies) of origin is given beyond "endemic and non-endemic regions."
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not specify the "number of experts" or their "qualifications" involved in establishing ground truth for the test sets.
- For the CDC Reference Panel, the ground truth is implicitly established by the CDC and Western Blot results, which are established methods for Lyme disease confirmation.
- For the Clinical Sensitivity Study, samples were "well-characterized clinically or culture confirmed Lyme disease samples." This implies a clinical diagnosis and/or laboratory confirmation (e.g., culture), but it doesn't detail the number or qualifications of clinicians/pathologists involved.
4. Adjudication Method for the Test Set
The document does not explicitly describe an "adjudication method" (e.g., 2+1, 3+1, none) for resolving discrepancies in ground truth establishment for the test set. Ground truth appears to be based on established clinical/laboratory practices (clinical diagnosis, culture, Western Blot).
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done
No Multi Reader Multi Case (MRMC) comparative effectiveness study comparing human readers with and without AI assistance is mentioned. The device, Sofia Lyme FIA, is an automated diagnostic test that provides a reading directly, not an AI-assisted interpretation for human readers.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
Yes, the studies described are standalone performance studies of the Sofia Lyme FIA device. The device uses immunofluorescence and an automated analyzer to produce results ("Sofia scans the test strip, analyzes the fluorescent signal, and then displays two (2) test results"). There is no mention of a human-in-the-loop for interpreting the device's primary output. The results are then to be "used in conjunction with information obtained from the patient's clinical evaluation and other diagnostic procedures," indicating that while the device is standalone, its results are part of a broader diagnostic process.
7. The Type of Ground Truth Used
The ground truth used for validation includes:
- Established Reference Methods: Western Blot (for the CDC reference panel).
- Clinical Diagnosis/Culture Confirmation: For the clinical sensitivity study, "well-characterized clinically or culture confirmed Lyme disease samples" were used.
8. The Sample Size for the Training Set
The document does not provide information regarding a separate "training set" or its sample size. This type of regulatory submission typically focuses on validation and clinical performance of the finalized device, rather than the developmental training phase of an algorithm.
9. How the Ground Truth for the Training Set was Established
Since no specific "training set" is mentioned or detailed, there is no information provided on how its ground truth was established.
§ 866.3830
Treponema pallidum treponemal test reagents.(a)
Identification. Treponema pallidum treponemal test reagents are devices that consist of the antigens, antisera and all control reagents (standardized reagents with which test results are compared) which are derived from treponemal sources and that are used in the fluorescent treponemal antibody absorption test (FTA-ABS), theTreponema pallidum immobilization test (T.P.I.), and other treponemal tests used to identify antibodies toTreponema pallidum directly from infecting treponemal organisms in serum. The identification aids in the diagnosis of syphilis caused by bacteria belonging to the genusTreponema and provides epidemiological information on syphilis.(b)
Classification. Class II (performance standards).