Evaluation of an indigenous Western Blot kit for human immunodeficiency virus.

PURPOSE The Western Blot test is considered a gold standard test for the confirmation of an ELISA and/or rapid assay screened reactive sample in the diagnosis of HIV infection, especially in the low risk population. In this study, an indigenously developed HIV W. Blot kit (J.Mitra & Co., New Delhi, India) was compared for its performance characteristics with a widely used Western Blot kit, HIV Blot 2.2 (Genelabs, Singapore). Antigens of both HIV-1 and the indicator antigen gp36 of HIV-2 are included in the strips. METHODS A panel of 150 clinical serum samples was used in the evaluation. All the sera were tested simultaneously by both the kits. RESULTS The HIV W. Blot kit had high performance characteristics (100% sensitivity and 100% specificity), like the HIV Blot 2.2. The test procedure was easy to perform. There was clear delineation of the bands. CONCLUSIONS The interpretation of the results on the HIV W. Blot was less prone to subjective errors. The test gave positive bands at even very high serum dilutions in the test kit. This fact indicates that HIV W. Blot probably has a potential application in early phases of infection, when the antibody concentrations are still very low.