(222 days)
The Biotest EA IgM ELISA is an enzyme immunoassay using recombinant antigens for the qualitative detection of IgM antibodies to the Epstein-Barr Virus early antigens (EA) p54 and p138 in human serum or plasma. Results obtained with this test, in conjunction with other clinical and patient data obtained in assays for other Epstein-Barr virus-specific antibodies such as anti-Early Antigen IgG and anti-EBNA-1 IgG, assist in serological diagnosis of EBV infection in pediatric and adult populations.
Using recombinant DNA technology, Biotest has developed three highly purified EBV antigens for use in their ELISA test system.
- EBNA-1 p72: Major antigen of the EBNA complex. The recombinant protein does not contain the glycine-alanine copolymer, a structural feature of EBNA-1, which shows cross-reactivities with certain autoantibodies and CMV (IgM response).
- EA-D p64: Early antigen. Dominant immunogen of the EA-D complex.
- EA p138: Early antigen and major DNA binding protein. This highly reactive antigen is not detectable in EA immunofluorescence assays based on chemically induced Raji cells (deletion within the Raji genome).
The EBV immune status will be determined by the detection of specific antibodies directed against EBV proteins according to the principle of the indirect ELISA. The antigens are purified to apparent homogeneity and immobilized on the solid phase (microtest plate, 96 wells). If the patient's serum contains specific antibodies they will bind during the first incubation. Non-specific antibodies are removed by washing steps. During a second incubation the captured IgM antibodies are labeled. This is performed by addition of murine monoclonal anti-human IgM antibody-enzyme-conjugates. The final reaction converts a colorless substrate to a colored product. The concentration of color after a definite time is related to the concentration of antibody in the serum sample.
This appears to be a 510(k) summary for the Biotest Anti-EBV Recombinant EA IgM ELISA test. Let's break down the acceptance criteria and study details.
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state pre-defined "acceptance criteria" in terms of specific performance thresholds for sensitivity and specificity. Instead, it presents the results of a comparison study against a predicate device and clinical interpretation. However, we can infer the reported performance metrics.
| Performance Metric | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Primary Comparison (vs. VCA IgM/IgG IFA) | Not explicitly stated, but demonstrating substantial equivalence to the predicate device in terms of diagnostic performance. | Relative Sensitivity: 84.1% (Combined Sites) |
| Relative Specificity: 89.4% (Combined Sites) | ||
| Relative Agreement: 87.0% (Combined Sites) | ||
| Clinical Interpretation | Not explicitly stated, but demonstrating agreement with expected serological patterns. | Total Clinical Sensitivity: 98.2% |
| Total Clinical Specificity: 97.1% | ||
| Total Clinical Agreement: 98.0% | ||
| Cross-Reactivity | No unexpected cross-reactivity with common interfering substances (HSV, VZV, CMV, Toxoplasma, RF, ANA, ASL). | No cross-reactivity observed in tested rheumatoid factor positive, antinuclear antibody positive, and ASL positive samples. Limited non-reactivity in a subset of samples from patients acutely infected with HSV I/II, VZV, CMV, Toxoplasma (e.g., 4 of 5 for HSV I/II). |
| Reproducibility | Acceptable inter-run, intra-run, and inter-lab variability. | Inter-run % C.V.: 9.7% - 16.9% (Site 1), 3.1% - 7.7% (Site 2) |
| Intra-run % C.V.: 2.8% - 6.3% (Site 1), 6.8% - 14.7% (Site 2) | ||
| Inter-lab % C.V.: 7.9% - 15.7% |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: 408 patient samples.
- Data Provenance: Clinical study conducted at two geographically distinct locations. Samples were obtained from both pediatric and adult patients (ages 1 to 74). The study is retrospective in the sense that samples were collected and categorized prior to testing with the Biotest ELISA, allowing for comparison to existing diagnostic methods and clinical records. The document doesn't specify countries of origin, but given the US FDA submission, it's highly likely to be within the US.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not explicitly detail the number or qualifications of experts used to establish the "ground truth" for the test set.
- For the "direct comparison with VCA IgM/IgG IFA", the predicate device (Gull VCA IGM test kits, which is an Indirect Fluorescent Antibody (IFA) assay) serves as the reference, which itself would have been interpreted by trained laboratory personnel.
- For the "comparison with clinical interpretation," the ground truth was "based on antibody patterns and clinical diagnosis at the time the specimen was drawn." This implies that the initial diagnoses and serological classifications (e.g., acute, past, negative) were made by healthcare professionals and laboratory personnel, but no specific number or qualification of these experts is provided in this summary.
4. Adjudication Method for the Test Set
The document does not explicitly describe an adjudication method for conflicting results.
- For the direct comparison, it appears the results of the Biotest EA IgM ELISA were compared directly to the results of the VCA IgM/IgG IFA, with agreement or disagreement noted.
- For the clinical interpretation, "Result matches Biotest" and "Result does not match Biotest" categories suggest a direct comparison of the Biotest result against an established clinical interpretation for each sample.
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
- No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This document describes the validation of an ELISA diagnostic kit, not an AI-powered image analysis or diagnostic tool that would involve human readers interpreting results with or without AI assistance. Therefore, there is no effect size for human reader improvement with AI.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- Yes, a standalone performance evaluation was done. The Biotest EA IgM ELISA is a laboratory diagnostic test. Its performance (sensitivity, specificity, reproducibility, cross-reactivity) was evaluated as a standalone device, meaning the algorithm/assay itself directly produces the result (positive/negative) without human intervention in the interpretation of the assay's output during the performance study itself. Human intervention would be involved in performing the test and interpreting the final clinical significance, but the device's diagnostic output is standalone.
7. The Type of Ground Truth Used
Two types of ground truth were used:
- Predicate Device Comparison: The results of commercially available or published EBV VCA IgM/IgG IFA tests. This serves as a "reference standard" from an established, legally marketed diagnostic method.
- Clinical Interpretation: "Stage of infection based on antibody patterns and clinical diagnosis at the time the specimen was drawn." This combines serological profiles (antibodies against other EBV antigens) with the clinical presentation of the patient. This represents a more comprehensive "clinical ground truth."
8. The Sample Size for the Training Set
The document does not specify a separate "training set" or its sample size. This is typical for traditional immunoassay device submissions. The "clinical study of 408 patient samples" appears to be the primary validation set (test set) for evaluating the device's performance characteristics. Diagnostic kits like this are generally developed and optimized during an internal R&D phase, and the studies presented are for validation rather than training of a machine learning model.
9. How the Ground Truth for the Training Set Was Established
As no explicit "training set" is mentioned in the context of machine learning model development, this question is not directly applicable. For the development and optimization of the ELISA kit itself (which would be analogous to "training" in a broad R&D sense), the ground truth would have been established through extensive research using characterized EBV-infected and uninfected samples, likely verified by a combination of established serological methods, PCR, and clinical diagnosis, but these details are not part of this 510(k) summary.
§ 866.3235 Epstein-Barr virus serological reagents.
(a)
Identification. Epstein-Barr virus serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies to Epstein-Barr virus in serum. The identification aids in the diagnosis of Epstein-Barr virus infections and provides epidemiological information on diseases caused by these viruses. Epstein-Barr viruses are thought to cause infectious mononucleosis and have been associated with Burkitt's lymphoma (a tumor of the jaw in African children and young adults) and postnasal carcinoma (cancer).(b)
Classification. Class I (general controls).