Luh K T, Yu C J, Yang P C, Lee L N
Department of Laboratory Medicine, National Taiwan University Hospital, Taipei.
Respirology. 1996 Jun;1(2):145-51. doi: 10.1111/j.1440-1843.1996.tb00024.x.
An ELISA diagnostic test for tuberculosis antigen A60 (TBA60) IgG/IgM was used in a tertiary referral hospital in Taiwan. From June 1992 to December 1993, serum samples obtained from 907 patients were analyzed for TBA60 IgG and IgM titres. The final diagnosis of these patients was confirmed by microbiological study and clinical follow up for 18-24 months. Among 147 patients with active pulmonary tuberculosis, IgG was positive in 112 (76.2%), IgM was positive in 14 (9.52%). Among 90 patients with active extrapulmonary tuberculosis, IgG was positive in 53 (58.9%), IgM was positive in 9 (10%). Among 153 patients with inactive tuberculosis, IgG was positive in 28 (18.3%), IgM was positive in 1 (1.6%). Among 517 patients with nontuberculous disease, IgG was positive in 50 (9.7%), IgM was positive in 3 (0.6%). In this study population with 26% (237/907) active tuberculous infection rate, the TBA60 ELISA IgG had a diagnostic sensitivity of 69.6% and a specificity of 92.1%. These results indicate a positive predictive value of 67.9% and a negative predictive value of 89.2%. The sensitivity of IgM was 10.5% and specificity, 99.4%. The serum IgG tire had good correlation with the extent of pulmonary TB had a higher percentage of IgG seropositivity (83.9%) than those with smear-negative pulmonary TB (70.6%) and extrapulmonary TB (58.9%). In 50 cases with active tuberculosis, follow-up examinations were carried out one month after treatment. In 18 cases with initially negative IgG and IgM titres, 13 showed elevation of serum IgG titres into positive level, one had positive seroconversion of IgM which was the only serological marker indicating active infection. Therefore, 77.8% (14/18) gained diagnostic benefit from follow-up serological examination. It was concluded that TBA60 IgG and IgM ELISA is a useful test when diagnosing tuberculosis. This test also assists in the clinical judgement of tuberculosis when used as an adjunct to symptoms and sputum smear, and for monitoring therapeutic response at the commencement of treatment.
台湾一家三级转诊医院采用了一种检测结核抗原A60（TBA60）IgG/IgM的酶联免疫吸附测定（ELISA）诊断试验。1992年6月至1993年12月，对907例患者的血清样本进行了TBA60 IgG和IgM滴度分析。这些患者的最终诊断通过微生物学研究及18至24个月的临床随访得以确认。在147例活动性肺结核患者中，IgG阳性者112例（76.2%），IgM阳性者14例（9.52%）。在90例肺外活动性结核患者中，IgG阳性者53例（58.9%），IgM阳性者9例（10%）。在153例非活动性结核患者中，IgG阳性者28例（18.3%），IgM阳性者1例（1.6%）。在517例非结核疾病患者中，IgG阳性者50例（9.7%），IgM阳性者3例（0.6%）。在该研究人群中，活动性结核感染率为26%（237/907），TBA60 ELISA IgG的诊断敏感性为69.6%，特异性为92.1%。这些结果表明其阳性预测值为67.9%，阴性预测值为89.2%。IgM的敏感性为10.5%，特异性为99.4%。血清IgG滴度与肺结核的病情程度具有良好的相关性，痰涂片阳性肺结核患者的IgG血清阳性率（83.9%）高于痰涂片阴性肺结核患者（70.6%）及肺外结核患者（58.9%）。50例活动性结核患者在治疗1个月后进行了随访检查。在最初IgG和IgM滴度为阴性的18例患者中，13例血清IgG滴度升高至阳性水平，1例IgM发生血清学阳转，这是唯一表明活动性感染的血清学标志物。因此，77.8%（14/18）的患者通过随访血清学检查获得了诊断益处。研究得出结论，TBA60 IgG和IgM ELISA在诊断结核病时是一种有用的检测方法。该检测方法在辅助症状及痰涂片检查用于结核病临床判断以及监测治疗开始时的治疗反应方面也有帮助。
