(260 days)
The Access Toxo IgG assay is a paramagnetic-particle, chemiluminescent immunoassay for the qualitative and quantitative determination of IgG antibodies to Toxoplasma gondii in human serum using the Access Immunoassay Systems. The Access Toxo IgG assay aids in the diagnosis of Toxoplasma gondii infection and may be used to assess the immune status of pregnant women.
This product is not FDA cleared/approved for the screening of blood or plasma donors. Assay performance characteristics have not been established for immunocompromised or immunosuppressed patients, cord blood, neonatal specimens or infants.
The Access Toxo IgG assay is a paramagnetic-particle, chemiluminescent immunoassay for the qualitative and quantitative detection of Toxoplasma gondii-specific IgG antibody in adult human serum using the Access Immunoassay Systems.
The Access Toxo IgG assay consists of the reagent pack, calibrators, and quality controls (OCs), packaged separately. Other items needed to run the assay include substrate and wash buffer.
This document describes the premarket notification (510(k)) for the Beckman Coulter Access Toxo IgG assay, a chemiluminescent immunoassay for detecting IgG antibodies to Toxoplasma gondii in human serum. This product is intended to aid in the diagnosis of Toxoplasma gondii infection and assess the immune status of pregnant women.
The submission claims substantial equivalence to a legally marketed predicate device, the Access Toxo IgG assay (K080869). The primary difference highlighted is the instrument used: the new device runs on the DxI 9000 Access Immunoassay Analyzer, while the predicate runs on the Access 2 Immunoassay System.
Here's an analysis of the provided information, focusing on the study that proves the device meets the acceptance criteria:
1. Table of Acceptance Criteria and Reported Device Performance
Strictly speaking, the document does not present "acceptance criteria" in a separate table with yes/no compliance. Instead, it details specific performance metrics and their measured values. The implicit acceptance criterion for most analytical performance studies (like imprecision and method comparison) is that the new device's performance is acceptable for its intended use and comparable to or better than the predicate. For Linearity, LoB, LoD, and LoQ, the acceptance criterion is that the study supports the claimed values.
| Performance Characteristic | Acceptance Criteria (Implicit from Study Design/Claims) | Reported Device Performance (Access Toxo IgG on DxI 9000) |
|---|---|---|
| Method Comparison (vs. Access 2 Immunoassay System) | High Positive Percent Agreement (PPA) and Negative Percent Agreement (NPA) to demonstrate interchangeability between instruments. | PPA: 100.00% (40/40) with 95% CI = 91.24% to 100% (for Reactive samples) |
| NPA: 100.00% (99/99) with 95% CI = 96.26% to 100.00% (for Non-Reactive samples) | ||
| Imprecision (Within-Laboratory) | SD 3.2 IU/mL. (These are the design criteria mentioned, implying they are the acceptance threshold.) | Sample 1 (2.7 IU/mL): Overall Precision SD 0.38 (13.9% CV) - *Meets SD criterion (0.38 |
§ 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).