Importance of the cutoff ratio for detecting antibodies against hepatitis A virus in oral fluids by enzyme immunoassay

摘要: Multiple studies have examined the use of oral fluids in modified serum-based assays aiming to replace serum antibody detection for hepatitis A. However, reliable HAV immunity fluid requires an extremely sensitive assay; most immunoassays designed determination lack sufficient sensitivity this purpose. Consequently, "in-house" competitive enzyme immunoassay (EIA) specifically with samples collected using a ChemBio(®) device was developed detect total anti-HAV antibodies (IgG and IgM). This system compared in-house EIA commercial considered be "gold standard" corresponding (n=225) determine accuracy assay evaluate importance cutoff ratio fluids. When median optimal (ROC analysis) obtained from were compared, found 28.8% higher than cutoff. different values reduction about 17% shown essential increase test accuracy. At value 0.351, specificity higher, reaching 91.7% 86.2% (p<0.001, AUROC=0.915), respectively. The convenience, non-invasive nature method make it useful alternative discriminating between HAV-immune non-immune individuals.