Efficacy of Rapid Diagnostic Tests in Relation to ELISA in Hepatitis B and C Infection

Background: Hepatitis B surface antigen and Hepatitis C antibodies in circulation are the common markers used for diagnosis of Hepatitis B and C infection. Though ELISA is the gold standard for detection of these markers, rapid diagnostic tests like immunochromatography is used in most of the centers for quick screening of cases. This study is undertaken to compare the result of both methods. Method: Both ICT and ELISA test were done for Hepatitis B in 275 cases and for Hepatitis C in 207 cases. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of rapid diagnostic test are evaluated keeping ELISA as gold standard. Results: Out of total 275 cases, 33 cases were found to be positive for Hepatitis B by ELISA and 109 by immunochromatography method having sensitivity, specificity, positive predictive value, negative predictive value and accuracy of rapid diagnostic test as 100%, 76.1%, 30.2%, 100% and 78.3% respectively. In Hepatitis C, out of 207, 17 were positive by ELISA and 22 by ICT method with sensitivity, Specificity, positive predictive value, negative predictive value and accuracy of rapid diagnostic test as 100%, 97.4%, 77.27%, 100% and 97.64% respectively. Conclusion: Rapid diagnostic tests for detection of Hepatitis B and C must be used very cautiously after evaluation in particular population and before terming a particular case to be positive. An alternative gold standard method must be used to confirm the case.