抗-HIV1+2筛查试验阳性与免疫印迹试验对比结果的分析

Comparison between the HIV 1+2 screening positive and western blot test results.

目的对比分析艾滋病病毒(HIV 1+2)抗体筛查试验阳性结果与免疫印迹试验结果。方法对150份筛查复检为阳性标本的酶联免疫吸附试验(ELISA)与明胶颗粒凝集试验(PA)的结果,分别与同时检测的免疫印迹试验(WB)的结果进行比较,计算出ELISA、PA的符合率、敏感性和特异性,并依据ELISA的OD值变化探求与PA及WB结果的关系。结果ELISA、PA与WB的阳性符合率分别为89.93%和86.81%;ELISA的敏感性为100%,特异性为90.34%;PA的敏感性为100%,特异性为87.33%。凡经ELISA检测其S/CO值(平均18.63)远高于阳性对照S/CO值(平均6.677)的强阳性标本,与PA、WB的阳性符合率同为100%;经ELISA检测其S/CO值(平均0.8596)≤1或略大于1的标本,与PA、WB的阳性符合率分别为21.05%和0;经ELISA检测其S/CO值(平均2.648)>1、小于阳性对照S/CO值的标本,与PA、WB的阳性符合率分别为66.67%和0。结论筛查试验存在一定的假阳性结果,HIV抗体结果的报告必须以WB结果为准;ELISA、PA与WB确认结果不符的情况仅出现于确认为HIV-1抗体阴性及不确定的标本中。

Objective To compare and analyze the HIV 1 ＋ 2 screening positive results and Western Blot Test Resuits. Methods ELISA and PA results among 150 screening positive specimens were compared with Western Blot Test results. The coincidence rates of both sensitivity and specificity of ELISA and PA were calculated,and the relationship between PA and WE results was also explored in accordance with the variations of ELISA OD value. Results The positive coincidence rate of ELISA and PA with WE was 89.93 % and 86.81% respectively. The sensitivity was 100 % and specificity was 90.34% for ELISA, while the sensitivity was 100% and specificity was 87.33% for PA. Both of the coincidence rates of ELISA were 100% when the S/CO value （mean 18.63） was much higher than the cutoff value （mean 6.677） .The coincidence rate was 21 .05% and 0 when the S/CO value （mean 0.8596） was≤1 or slightly larger than the cutoff value among the specimens and the coincidence rate was 66.67 % and 0 when the S/CO value （mean 2. 648） was 〉 1 and 〈 the positive control value. Conclusion The final HIV antibody test results must be confirmed by Western Blot Test as several false positives do existe in the screening test. The results of ELISA and PA conflict with WE results only in confirmed HIV-1 negative or unconfirmed specimens.