(175 days)
An enzyme-linked immunosorbent assay (ELISA) designed for the detection and measurement of circulating antibodies to native DNA. These autoantibodies are often associated with systemic lupus erythematosus (SLE) and give positive results in screening tests for antinuclear antibodies.
An enzyme-linked immunosorbent assay (ELISA) designed for the detection and measurement of antibodies to native DNA in human serum.
The ELISA methodology is commonly used for serum antibody evaluations. Purified native DNA has been attached to the inner surfaces of the microwell plate. During the initial incubation step, antibodies in patient serum bind specifically to the immobilized antigen and remain in place after a wash step.
A second antibody which is conjugated to horseradish peroxidase (HRP) is used to recognize the "heavy + light" chain regions of the patient's DNA antibodies that remain after the wash step. In the wells where the second antibody remains bound. the conjugated HRP catalyzes a color change in the substrate. After the reaction is stopped, the color is read in an EIA Plate reader.
Acceptance Criteria and Study Details for Hemagen® DNA Kit (K962276)
Based on the provided text, the Hemagen® DNA Kit is an enzyme-linked immunosorbent assay (ELISA) designed for the detection and measurement of antibodies to native DNA in human serum, primarily associated with systemic lupus erythematosus (SLE).
1. Acceptance Criteria and Reported Device Performance
The acceptance criteria for this device are not explicitly stated in numerical thresholds but are implied through "comparative studies" demonstrating "substantial equivalence" to the predicate device. The performance data provided focuses on precision and comparative analytical performance.
| Acceptance Criteria Category | Specific Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Precision (Reproducibility) | Low variability in repeated measurements (not quantified). | Inter-assay (%CV): Range 6.2-12.4% for IU/mL, 7.4-12.3% for O.D. (n=8 samples, 50 readings each). |
| Intra-assay (%CV): Range 2.6-17.0% for IU/mL, 2.2-13.9% for O.D. (n=8 samples, 20 consecutive readings each). | ||
| Correlation with WHO Standard | High degree of correlation with the WHO Anti-Double Stranded DNA 1st International Standard. | A study was conducted to demonstrate a high degree of correlation between kit calibrators and the W.H.O. Standard (specific coefficients or metrics are not provided). |
| Analytical Sensitivity (vs. Predicate) | 100% agreement with predicate for positive disease samples. | 100% (23/23) for disease state patients (N=100) after adjudication. |
| Analytical Specificity (vs. Predicate) | High agreement with predicate for negative disease samples. | 97.4% (75/77) for disease state patients (N=100) after adjudication. |
| Agreement with Predicate (Normal Donors) | 100% agreement with predicate for healthy normal samples. | 100% (40/40) for normal blood donors (N=40). |
| Interfering Substances | Less than 15% variation from certain levels of interferents. | Variation |
§ 866.5100 Antinuclear antibody immunological test system.
(a)
Identification. An antinuclear antibody immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the autoimmune antibodies in serum, other body fluids, and tissues that react with cellular nuclear constituents (molecules present in the nucleus of a cell, such as ribonucleic acid, deoxyribonucleic acid, or nuclear proteins). The measurements aid in the diagnosis of systemic lupus erythematosus (a multisystem autoimmune disease in which antibodies attack the victim's own tissues), hepatitis (a liver disease), rheumatoid arthritis, Sjögren's syndrome (arthritis with inflammation of the eye, eyelid, and salivary glands), and systemic sclerosis (chronic hardening and shrinking of many body tissues).(b)
Classification. Class II (performance standards).