结核菌素抗体对儿童结核病的诊断价值

The Body Fluid Purified Protein Derivative Antibody Tests:Diagnosis Value in Pediatric Tuberculosis

目的评价体液结核菌素(PPD)抗体在小儿结核病中的诊断价值。方法回顾性分析126例行PPD检查的住院患儿,其中确诊结核病22例。利用临床流行病学方法分别计算体液PPD抗体检测对结核病的特异性、敏感性、似然比、预测值及不同患病率下的验后概率。结果体液PPD抗体检测对小儿结核病的敏感性和特异性分别为45．45％和 91．35％,阳性和阴性似然比分别为5．25和0．597,阳性预测值为52．63％,阴性预测值为88．79％。患病率为15％时,验后概率为48．09％。结论体液PPD检测对小儿结核病的诊断价值有限,临床医师应谨慎对待体液 PPD检测阳性结果,其诊断价值与所处医院患儿结核病患病率有关。

Objective To evaluate the diagnosis value of purified protein derivative （PPD） antibody tests in childhood tuberculosis. Methods We reviewed 126 cases of hospitalization children tested body fluid PPD antibody by Enzyme-Linked Immunosorbent Assay （ELISA）. Twenty-two them were diagnosed with tuberculosis. We determined the sensitivity, specificity, diagnostic likelihood ratio, positive prognostic value, negative prognostic value, post-test probability, respectively. Results The following accuracy statistics for the PPD body liquid antibody tests in this study： sensitivity, 45.45%; specificity, 91.35%; diagnostic likelihood ratio positive, 5.25; diagnostic likelihood ratio negative, 0.597; positive predictive value, 52.63%; negative predictive value, 88.79% and post-test probability, 48.09% in 15% of prevalence. Conclusion This study shows that body fluid PPD tests have limited value for diagnosis of tuberculosis in pediatric tuberculosis. Clinic physicians should be wary of the positive results of body fluid PPD antibody tests. The value of diagnosis is related to prevalence of tuberculosis in the specific hospital.