(117 days)
The INCSTAR Toxoplasma IgG "fast" ELISA kit contains instructions and materials for the qualitative and/or semi-quantitative detection of IgG antibodies to Toxoplasma gondii in human serum by indirect enzyme-linked immunosorbent assay (ELISA) technique. When performed according to instructions, the Toxoplasma IqG "fast" ELISA test is of value in the determination immunological response to infection with Toxoplasma gondii. The evaluation of paired sera, acute and convalescent, by demonstrating seroconversion or a significant rise in antibody can aid in the diagnosis of primary or reactivated infection with Toxoplasma gondii. This product is not FDA cleared for use in testing (i.e., screening) blood or plasma donors.
The method for the determination of specific anti-Toxoplasma IgG utilizes the enzyme-linked immunosorbent assay (ELISA) technique. Polystyrene microtiter wells are coated with purified Toxoplasma gondii antigen. Diluted patient serum is incubated with the purified antigen bound to the solid surface of a microtiter well. The Toxoplasma IgG antibodies present in a patient's serum will be captured by the solid phase. After washing, affinity purified polyclonal goat antihuman IgG (Fc) antibodies conjugated to horseradish peroxidase are added to the well. After this incubation, chromogen containing tetramethylbenzidine is added. Enzyme action on the chromogen results in a color reaction. The color can be detected with a photometer at a dual wavelength of 450 nm / 630 nm. The measured enzyme activity is directly proportional to the concentration of specific anti-Toxoplasma IgG bound to the solid phase.
This is an ELISA kit, not an AI device. The questions are not applicable. I will extract the available information.
Acceptance Criteria and Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Relative Sensitivity: 97% to 100% (95% CI) | 97% to 100% |
| Relative Specificity: 95% to 100% (95% CI) | 95% to 100% |
| Overall Agreement: 97% to 100% (95% CI) | 97% to 100% |
Study Details
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Sample size used for the test set and the data provenance: 294 serum samples representing 263 individuals. The provenance of the data (e.g., country of origin, retrospective or prospective) is not explicitly stated, but the samples represented a mixed population including infants, transplant patients, immunocompromised hosts, pregnant women being screened for Toxoplasmosis, and patients with various other illnesses.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts: Not applicable. The "ground truth" was established by comparison to a legally marketed predicate device (Gull Toxoplasma IgG ELISA, K915891), not by expert opinion.
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Adjudication method for the test set: Not applicable. The comparison was against a predicate device.
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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: Not applicable. This is an ELISA kit, not an AI device.
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If a standalone (i.e., algorithm only without human-in-the-loop performance) was done: Not applicable. This is an ELISA kit, not an AI device. The performance reported is that of the assay.
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The type of ground truth used: Comparison with the results generated from the legally marketed predicate device, the Gull Toxoplasma IgG ELISA (K915891).
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The sample size for the training set: Not applicable. This is an immunoassay kit, not a machine learning model where a "training set" would be used in the same context. The device's performance characteristics are established through validation studies.
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How the ground truth for the training set was established: Not applicable.
§ 866.3780
Toxoplasma gondii serological reagents.(a)
Identification. Toxoplasma gondii serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies toToxoplasma gondii in serum. Additionally, some of these reagents consist of antisera conjugated with a fluorescent dye (immunofluorescent reagents) used to identifyToxoplasma gondii from clinical specimens. The identification aids in the diagnosis of toxoplasmosis caused by the parasitic protozoanToxoplasma gondii and provides epidemiological information on this disease. Congenital toxoplasmosis is characterized by lesions of the central nervous system, which if undetected and untreated may lead to brain defects, blindness, and death of an unborn fetus. The disease is characterized in children by inflammation of the brain and spinal cord.(b)
Classification. Class II (performance standards).