(90 days)
MRL Diagnostics' HSV-2 ELISA IgG test is intended for qualitatively detecting the presence or absence of human IgG class antibodies to HSV-2 in human sera. In conjunction with the MRL HSV-1 ELISA IgG, the test is indicated for testing sexually active adults or expectant mothers for aiding in the presumptive diagnosis of HSV infection. The predictive value of a positive or negative result depends on the population's prevalence and the pretest likelihood of HSV-2 infection. The performance of this assay has not been established for use in a pediatric population, for neonatal screening, for testing of immunocompromised patients, or for use with automated equipment.
In the MRL Diagnostics HSV-2 ELISA IgG assay, the polystyrene microwells are coated with recombinant gG-2 antigen. Diluted serum samples and controls are incubated in the wells to allow specific antibody present in the samples to react with the antigen. Nonspecific reactants are removed by washing, and peroxidase-conjugated anti-human IgG is added and reacts with specific IgG. Excess conjugate is removed by washing. Enzyme substrate and chromogen are added, and the color is allowed to develop. After adding the Stop Reagent, the resultant color change is quantified by a spectrophotometric reading of optical density (OD). Sample optical density readings are compared with reference cut-off OD readings to determine results.
Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text for the MRL Diagnostics HSV-2 ELISA IgG device (K993724):
The provided text describes a 510(k) summary for a medical device, which typically focuses on demonstrating substantial equivalence to a predicate device rather than setting explicit "acceptance criteria" for performance in the same way a clinical trial might. However, we can infer performance targets based on the data presented and comparisons to the reference methods.
1. Table of Acceptance Criteria (Inferred) and Reported Device Performance
| Characteristic | Inferred Acceptance Criteria/Target (from Predicate/Clinical Relevance) | Reported Device Performance (MRL HSV-2 ELISA IgG) |
|---|---|---|
| Relative Sensitivity (Sexually Active Adults) | High sensitivity, comparable to WB (e.g., >90%) | 96.1% (73/76) against Western Blot (95% CI: 88.9-99.2%) |
| Relative Specificity (Sexually Active Adults) | High specificity, comparable to WB (e.g., >95%) | 97.0% (159/164) against Western Blot (95% CI: 93.0-99.0%) |
| Relative Sensitivity (Expectant Mothers) | High sensitivity, comparable to WB (e.g., >95%) | 100% (58/58) against Western Blot (95% CI: 93.8-100%) |
| Relative Specificity (Expectant Mothers) | High specificity, comparable to WB (e.g., >95%) | 96.1% (172/179) against Western Blot (95% CI: 92.1-98.4%) |
| Sensitivity (Culture Positives) | High sensitivity, comparable to culture (e.g., >90%) | 96.8% (61/63) against Culture (95% CI: 89.0-99.6%) |
| 98.4% (61/62) against Western Blot (95% CI: 91.3-100%) | ||
| Specificity (Low Prevalence Population) | High specificity (e.g., >95%) | 98.7% (77/78) against Western Blot (95% CI: 93.1-100%) |
| Type Specificity (HSV-1 WB Positives, HSV-2 WB Neg) | High type-specificity (e.g., >90% to avoid confusion with HSV-1) | 96.5% (276/286) against Western Blot (95% CI: 93.7-98.3%) |
| Agreement with CDC Panel | High agreement (e.g., >95%) | 100% total agreement with CDC results (100% agreement with positive, 100% with negative specimens) |
| Cross-reactivity with Related Viruses | Low cross-reactivity (e.g., >90% negative agreement) | CMV: 91.7%, EBV VCA: 90.9%, HHV6: 90.9%, VZV: 90.5% (Total: 90.9%) |
| Intra-assay Reproducibility (%CV) | Low variability (e.g., |
§ 866.3305 Herpes simplex virus serological assays.
(a)
Identification. Herpes simplex virus serological assays are devices that consist of antigens and antisera used in various serological tests to identify antibodies to herpes simplex virus in serum. Additionally, some of the assays consist of herpes simplex virus antisera conjugated with a fluorescent dye (immunofluorescent assays) used to identify herpes simplex virus directly from clinical specimens or tissue culture isolates derived from clinical specimens. The identification aids in the diagnosis of diseases caused by herpes simplex viruses and provides epidemiological information on these diseases. Herpes simplex viral infections range from common and mild lesions of the skin and mucous membranes to a severe form of encephalitis (inflammation of the brain). Neonatal herpes virus infections range from a mild infection to a severe generalized disease with a fatal outcome.(b)
Classification. Class II (special controls). The device is classified as class II (special controls). The special control for the device is FDA's revised guidance document entitled “Class II Special Controls Guidance Document: Herpes Simplex Virus Types 1 and 2 Serological Assays.” For availability of the guidance revised document, see § 866.1(e).