体金法与TPPA法在街头献血者梅毒筛查中的应用

Analysis of the application of colloidal gold and TPPA in screening for syphilis among street blood donors

目的:探究分析胶体金法(TPAb)与梅毒螺旋体明胶颗粒凝集试验(TPPA)在街头献血者梅毒筛查中的应用。方法:选取2019-01~2020-06参与街头无偿献血者6250例,其中5018例无偿献血者血液标本(甲组),先采用TPPA法进行梅毒抗体检测,对于TPPA阳性者进一步应用胶体金法进行复查。对1232例血液标本(乙组),先采用胶体金法进行检测,对胶体金法阳性者进一步用TPPA法进行复查。选取8例两种检测均阳性的标本,取阴性血清分别按比例进行稀释,分别采用胶体金法和TPPA法对各稀释后的标本进行定性检测,评价胶体金法相比于TPPA法的灵敏度及可检测范围。结果:甲组5018例血液标本组经TPPA检测显示阳性104例,胶体金法复查显示阳性100例,阳性符合率为96.15%;以TPPA法为“金标准”,胶体金法阳性漏诊率为0.08%。乙组经胶体金法检测显示阳性23例,1209例阴性。采用TPPA法对胶体金法检测阳性的23例标本进行复查,阳性符合率为86.96%,胶体金法检测的假阳性率为13.04%。胶体金法可检测至TPPA法下限的1/4~1/2,有着较宽的检测范围,能够检测到下限的1024倍甚至以上。结论:胶体金法由于敏感度高、操作简便、试剂便于保存、可独立包装、易对结果作出判断等优势,可作为基层医院的梅毒筛查手段。

Objective:To explore the application of colloidal gold assay(TPAB)and Treponema pallidum gelatin particle agglutination test(TPPA)in the screening of syphilis in street blood donors.Methods:From January 2019 to June 2020,6250 samples of free blood donors were selected,of which 5018 samples were collected(group A).First,TPPA method was used to detect syphilis antibody,and then colloidal gold method was used to reexamine those positive for TPPA.Blood samples of 1232 patients(group B)were detected by colloidal gold method first,and those positive for colloidal gold method were further reexamined by TPPA method.Eight samples positive for both tests were selected,and the negative serums were diluted proportionally.Colloidal gold method and TPPA method were used for qualitative detection of each diluted specimen,respectively,to evaluate the sensitivity and detectable range of Colloidal gold method compared with TPPA method.Results:A total of 104 cases of 5018 cases in group A were positive by TPPA test,and 100 cases were positive by colloidal gold test.The positive coincidence rate was 96.15%.Taking TPPA method as the"gold standard",the rate of missed diagnosis by colloidal gold method was 0.08%.In group B,23 cases were detected positive by colloidal gold method,and 23 cases were reexamined by TPPA method.The positive coincidence rate was 86.96%,and the false positive rate was 13.04%.Colloidal gold method can be detected to 1/4-1/2 of the lower limit of TPPA method,with a wide detection range,and can detect 1024 times or more of the lower limit.Conclusion:Colloidal gold method can be used as a screening method for syphilis in primary hospitals because of its advantages such as high sensitivity,simple operation,convenient preservation of reagents,independent packaging and easy judgment of results.