ABSTRACT
Objective To investigate the rate and the population distribution of subjects with indeterminate result of HIV antibody test and to understand the relationships between the western blot(WB)banding patterns and HIV infection through follow-up reexamination. Methods Samples with indeterminate results of HIV antibody test were collected by Jiading Center for Disease Control and Prevention from 2013 to 2017. They were used for analysis of the source, the distribution of Western blotting band pattern and the follow-up results. Results Among 698 samples required to be re-tested for confirmation of HIV infection, 151(21.63%)showed indeterminate WB test results. There were 18 types of WB band in 151 HIV antibody-indeterminate samples. The most common band types, accounting for 79.47%, were p24, gp160, and gp160p24. One hundred(among 151)subjects were followed up and the success follow-up rate was 50.00%. Among them, 28(56.00%)samples were still with indeterminate results of HIV antibody, 11(22.00% turned to be negative and 11(22.00%)turned to positive. The follow-up confirmatory tests showed that 67.86% of the samples with p24 band were still with indeterminate results and 40.00% of the samples with gp160 band became HIV antibody-negative. The samples with one of the three band patterns of gp160gp120p24, gp160p24p17 and gp160gp120p66p51 all became HIV antibody-positive. Conclusion The detection rate of indeterminate HIV antibody results varies in different populations. Positive conversion rates with different WB band patterns are different. Follow-up of the populations with specific WB band patterns should be strengthened to detect HIV infection cases as early as possible.
ABSTRACT
BACKGROUND: In Korean Red Cross, recombinant immunoblot assay (RIBA) has been used for the confirmatory test of HCV positive units since 1995. To certify the HCV infection in blood donors who showed the 'indeterminate result on the RIBA test, this study was performed. METHODS: Three enzyme immunoassay (EIA) kits (LG HCD 3.0, DONG-A HCV 3.0, and ORTHO HCV 3.0)and RNA detection method were employed to evaluate infection state of 135 samples of the 'indeterminate in the RIBA test. RESULTS: The 52.6% of the samples showed the same test results with three EIA kits. Fifteen samples (11.1%) were HCV RNA positive with RT-PCR-hybridization technique. Among 15 samples of HCV RNA positive, 13 (86.7%), 13 (86.7%), and 14(93.3%) of samples were positive in LG HCD 3.0, Ortho HCV 3.0 and Dong-A HCV 3.0 EIA, respectively. In the analysis of RIBA band reaction, HCV RNA positivity were correlated with core14, core518, and 897 antigen. However, among 64 samples which react with core antigen only, five samples (7.8%) were HCV RNA positive. CONCLUSION: Based on the results of the present study, it is recommend that the HCV RNA test be used as a method of confirmatory test in order to notify exact HCV positivity status to blood donor who showed indeterminate RIBA result.