Diagnostic accuracy study of a factor VIII ELISA for detection of factor VIII antibodies in congenital and acquired haemophilia A.

摘要: Antibody formation to factor VIII (FVIII) remains the greatest clinical and diagnostic challenge haemophilia-treating physician. Current guidance for testing inhibitory FVIII antibodies (inhibitors) recommends functional Nijmegen-Bethesda assay (NBA). A ELISA offers a complementary, immunological approach antibody testing. It was aim of this study retrospectively evaluate performance (index) detection antibodies, compared with NBA (reference). All samples sent routine at two haemophilia Comprehensive Care Centres, were tested in parallel using solid-phase, indirect kit (Immucor). total 497 from 239 patients (severe A=140, non-severe A=85, acquired A=14) available analysis. Sixty-three positive by (prevalence 12.7 %, 95 % confidence interval [CI], 9.9–15.9 %), median inhibitor titre 1.2 BU/ml (range 0.7–978.0). The demonstrated specificity 94.0 % (95 %CI, 91.3–96.0), sensitivity 77.8 % 65.5–87.3), negative predictive value 96.7 % 94.5–98.2), 65.3 % 53.5–76.0), likelihood ratio 0.2 0.1–0.4), 13.0 8.7–19.3) odds 54.9 27.0–112.0). Strong correlation (r=0.77, p< 0.001) seen between results (log adjusted) optical density. In conclusion, simple, specific, surveillance method enabling batch non-urgent presence antibodies.