Differential analysis of human immunodeficiency virus-related antibody detected by enzyme linked immunosorbent assay and western blot

Objective To investigate the difference of enzyme linked immunosorbent assay(ELISA)and western blotting(WB)in detection of human immunodeficiency virus(HIV)antibody. Methods HIV antibody detections were performed for 105 suspected HIV-infected patients in areas of Tongchuan City of Shaanxi Province, after the initial screening by ELISA and recheck of reverse transcription-polymerase chain reaction(RT-PCR), the results were re-verified by WB. The differences between result of early screening by detection of ELISA as well as recheck of RT-PCR and WB verification, and between ratio of the absorbance value to cut-off value(S/CO)of ELISA detection and results of WB verification were analyzed. Result of reaction band type of WB test was observed. Results Out of 105 suspected HIV-infected patients, 98 cases were diagnosed as double positive findings detected by ELISA and RT-PCR, and 87 positive cases were confirmed as HIV infection by WB, with a coincidence rate of 88.78%(87/98). In patients with positive results by ELISA but negative results by RT-PCR, one case was confirmed as positive result by WB, with a coincidence rate of 20.00%(1/5). The coincidence rates were the highest when S/CO value<1 and S/CO≥10 obtained by ELISA test compared with the WB verification result. Among the 87 positive samples confirmed by WB, the occurrence rates of gp160 and gp120 reached 100.00%, followed by gp41, p24 - and p17, with their occurrence rates of 95.40, 64.37% and 56.32%, respectively, and another 2.30% samples showed no specific HIV antibody band. Conclusion Both ELISA and WB detection can improve the coincidence rate of HIV antibody detection. However, there are negative or uncertain samples after WB validation. Therefore, such patients should be tracked and given further testing.