(287 days)
The Trinity Biotech Captia™ Herpes Simplex Virus (HSV) 1 Type Specific IgG kit is an Enzyme-linked Immunosorbent Assay (ELISA) intended for qualitatively detecting the presence or absence of human IgG class antibodies to HSV-1 in human serum. In conjunction with the Trinity Biotech Captia™ Herpes Simplex Virus (HSV) 2 Type Specific IgG kit, the test is indicated for testing sexually active adults or expectant mothers for aiding in the presumptive diagnosis of HSV infection. Due to the implications of positive results, it is recommended they be confirmed in a low prevalence population with Western blot. 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. The user is responsible for establishing assay performanace in these populations and with automated equipment
The Captia™ HSV 1 IgG Type Specific kit is an Enzyme-Linked Immunosorbent Assav (ELISA) for the qualitative determination of IgG antibodies in human serum to Herpes simplex Type 1 antigen. The Captia™ HSV 1 IgG Type Specific assay may be used as an aid in the diagnoses of Herpes infection.
For In Vitro Diagnostic Use Only.
The Captia™ HSV 1 IgG Type Specific test is an Enzyme-Linked Immunosorbent assay to detect IgG antibodies to Herpes simplex 1 antigen. Purified recombinant HSV gG1 antigen is attached to a solid phase microtiter well. Diluted test sera is added to each well. If the antibodies are present that recognize the antigen, they will bind to the antigen in the well. After incubation, the wells are washed to remove unbound antibody. An enzyme labeled anti-human IgG is added to each well. If antibody is present, it will bind to the antibody attached to the antigen on the well. After incubation, the wells are washed to remove unbound conjugate. A substrate solution is added to each well. If enzyme is present, the substrate will undergo a color change. After an incubation period, the reaction is stopped and the color intensity is measured photometrically, producing an indirect measurement of specific antibody in the patient specimen.
Here's a breakdown of the acceptance criteria and study information for the Captia™ HSV 1 IgG Type Specific ELISA Test Kit, based on the provided text:
Acceptance Criteria and Reported Device Performance
The acceptance criteria are implicitly defined by the performance characteristics presented in the study. The device is deemed acceptable if its agreement with the predicate device (Western Blot or other ELISA) falls within certain confidence intervals, demonstrated across various patient populations.
| Acceptance Criteria (Implied) | Reported Device Performance | 95% Confidence Interval (CI) |
|---|---|---|
| Expectant Mothers (vs. HSV 1 Western Blot) | ||
| % Agreement Positive to WB: Acceptably high | 87.74% (136/155) | 82.6-92.9% |
| % Agreement Negative to WB: Acceptably high | 98.18% (54/55) | 90.3-100.0% |
| Sexually Active Adults (vs. HSV 1 Western Blot) | ||
| % Agreement Positive to WB: Acceptably high | 87.93% (102/116) | 82.0-93.9% |
| % Agreement Negative to WB: Acceptably high | 100.00% (80/80) | 95.5-100.0% |
| Low Prevalence Population (vs. HSV 1 Western Blot) | ||
| % Agreement Positive to WB: Acceptably high | 79.25% (42/53) | 65.9-89.2% |
| % Agreement Negative to WB: Acceptably high | 97.71% (128/131) | 93.5-99.5% |
| Culture Positives (vs. Culture) | ||
| % Agreement Positive to Culture: Acceptably high | 69.81% (37/53) | 55.7-81.7% |
| Culture Positives (vs. HSV 1 Western Blot) | ||
| % Agreement Positive to WB: Acceptably high | 81.82% (36/44) | 67.3-91.8% |
| Alternate HSV 1 Type Specific IgG ELISA | ||
| Percent Positive Agreement: Acceptably high | 93.88% (92 / 98) | 87.2 - 97.7% |
| Percent Negative Agreement: Acceptably high | 97.06% (99 / 102) | 91.6 - 99.4 % |
| Percent Agreement: Acceptably high | 95.50% (191 / 200) | 91.6 - 97.9 % |
| Type Specificity with HSV 2 Western Blot Positives | ||
| Type-specificity relative to WB: Acceptably high | 96.4% (54/56) | 87.7-99.6% |
| Type cross-reactivity relative to WB: Acceptably low | 3.6% (2/56) | 0.43-12.3% |
Study Details
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Sample sizes used for the test set and the data provenance:
- Expectant Mothers: n = 210 sera. Data provenance: Consented, coded, unselected, banked, and masked sera. Country of Origin: Not specified beyond "Pacific Northwest university" which references the Western Blot. Retrospective (banked sera).
- Sexually Active Adults: n = 198 sera. Data provenance: Consented, unselected, and masked sera. Country of Origin: Not specified beyond "Pacific Northwest university". Retrospective (masked sera implies pre-collected).
- Low Prevalence Population: n = 184 sera. Data provenance: Unselected, banked, and masked sera. Country of Origin: Not specified beyond "Pacific Northwest university". Retrospective (banked sera).
- Culture Positives: n = 53 sera. Data provenance: Unselected, retrospective, and masked sera from patients at least six weeks but not more than one year post clinical presentation and culture. Country of Origin: Not specified beyond "Pacific Northwest university". Retrospective.
- Alternate HSV 1 Type Specific IgG ELISA Comparison: n = 200 specimens. Data provenance: Prospective, unselected, sequentially submitted specimens. Country of Origin: Not specified beyond "Pacific Northwest University".
- Type Specificity with HSV 2 Western Blot Positives: n = 56 sera. Data provenance: Samples from the "above described populations" (expectant mothers, sexually active adults, low prevalence persons, and HSV 2 culture positives) that were HSV 2 Western Blot positive and HSV 1 Western Blot negative. Country of Origin: Not specified beyond "Pacific Northwest University". Retrospective.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
The document does not explicitly state the number or qualifications of experts used to establish the ground truth. The ground truth (reference method) was established by an "HSV 1 Western Blot (WB) from a Pacific Northwest university" or "culture" for some cases. While Western Blot interpretation requires expertise, no details about the experts are provided. -
Adjudication method for the test set:
The document does not mention an adjudication method for the test set. Results from the Trinity ELISA were compared directly against the Western Blot or culture reference method. For the expectant mothers and low prevalence population studies, "equivocal" results from the Trinity ELISA were excluded from the percentage agreement calculations but reported in the raw counts. -
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 device is an in-vitro diagnostic ELISA kit, not an AI-assisted diagnostic tool that would involve human readers interpreting results with or without AI. The evaluation is solely on the performance of the assay itself compared to a reference method. -
If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
Yes, the studies presented are all standalone performance evaluations of the Captia™ HSV 1 IgG Type Specific ELISA kit. The performance metrics (e.g., % agreement positive, % agreement negative) are direct comparisons between the ELISA results and the reference method (Western Blot or culture) without human interpretation being factored in beyond the initial reading of the ELISA and the reference method itself. -
The type of ground truth used:
The primary type of ground truth used was:- Expert Consensus / Established Reference Method: Western Blot (HSV 1 Western Blot, HSV 2 Western Blot). The Western Blot is considered a gold standard for type-specific HSV serology.
- Pathology / Outcomes Data: Culture (for the "Culture Positives" study), indicating active infection.
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The sample size for the training set:
The document does not provide information on a training set. The presented studies are performance evaluations of the final device, implying that any training and development would have occurred prior to these validation studies. Therefore, the sample sizes mentioned are for the test sets. -
How the ground truth for the training set was established:
Since no training set details are provided, the method for establishing its ground truth is also not mentioned.
§ 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).