两种血吸虫病免疫诊断试剂的比较研究

Comparison study on two immuno-assays for schistosomiasis diagnosis

目的评价日本血吸虫抗体磁分离酶联免疫试剂盒（magnetic particle antibody immunoassay,MPAIA）与血吸虫循环抗原酶联免疫吸附试剂盒（ELISA）在血吸虫病免疫诊断中的应用效果.方法采取随机单盲法,分别用MPAIA法和ELISA法检测经病原学确诊的急性和慢性日本血吸虫病、并殖吸虫病、钩虫病、旋毛虫病、囊尾蚴病、华支睾吸虫病、乙肝患者血清及非疫区健康人血清,评价这两种试剂盒的灵敏度、特异度、Youden指数、一致百分率、阳性似然比和阴性似然比等指标. 结果MPAIA法和ELISA法检测确诊急性日本血吸虫病患者血清阳性符合率分别为100%和89.13%,MPAIA与ELISA法的差别无统计学意义（χ^2=1.125,P〉0.05）,两者检出结果呈高度一致（kappa=0.891）;检测确诊慢性日本血吸虫病患者血清阳性符合率分别为100%和17.65%,MPAIA法显著高于ELISA法（χ^2=36.36,P〈0.05）,两者结果一致性低（kappa=0.194）.检测非疫区健康人特异度分别为100%和98%;MPAIA法除与并殖吸虫交叉反应率为8.33%外,与其他寄生蠕虫病无交叉反应发生,ELISA法与其他寄生蠕虫无交叉反应现象,根据金标准确定的血吸虫病阳性检测结果和非疫区健康人检测结果,上述两种检测试剂的Youden指数为1和0.5436,一致百分率为100%和76.19%,阳性似然比为∞和28.18,阴性似然比为0和0.44. 结论MPAIA与ELISA法均可用于现场筛查,但MPAIA在检测慢性血吸虫方面检测性能优于ELISA.

Objective To evaluate the efficacy of Schistosoma japonicum antibody immunoassay kit （magnetic particle antibody immunoassay, MPAIA） and Schistosoma circulating antigen detection kit （ELISA） for schistosomiasis diagnosis. Methods The serum samples of the patients suffering from schistosomiasis, paragonimosis, hookworm disease, trichinelliasis, cysticercosis, clonorchiasis or hepatitis and healthy people were tested single-blinded and randomly by MPAIA and ELISA respectively to evaluate diagnostic performance by the parameters of sensitivity, specificity, Youden index, coincidence rate, positive likelihood ratio and negative likelihood ratio, etc.. Results For acute schistosomiasis japonica, the sensitivity of MPAIA and ELISA were 100% and 89. 13% , respectively. There was no difference between the performance of two kits （χ^2= 1. 125,P〉0.05）, and the consensus was high （kappa = 0.891）. For chronic schistosomiasis japonica, the sensitivity were 100% and 17. 65% .respectively. MPAIA was significantly more sensitive than ELISA（χ^2 = 36. 36,P〈0.05）, and the consensus was very low （kappa =0.194）. In non-endemic area, the specificity of the two kits were 100% and 98% respectively when used in healthy people. Except cross-reactivity of 8. 33% with paragonimiasis, MPAIA exhibited no cross-reactivity with other helminthes infection. When MPAIA and ELISA were used to test individuals infected with schistosomiasis japonica and healthy people from non-endemic area, who had been diagnosed using the gold-standard method, the Youden＇s index were 1 and 0. 5436 while the coincidence ratio were 100% and 76. 19% , positive likelihood ratio were oo and 28. 18, negative likelihood were 0 and 0.44, respectively. Conclusion Both MPAIA and ELISA can be used for on-site screening of schistosomiasis, but MPAIA is superior to ELISA for the detection of chronic schistosomiasis.