Ipuge Y A, Rieder H L, Enarson D A
Ministry of Health, Dar es Salaam, Tanzania.
Trans R Soc Trop Med Hyg. 1996 May-Jun;90(3):258-61. doi: 10.1016/s0035-9203(96)90239-4.
Routine results of direct examination of sputum smears for acid-fast bacilli from 34 laboratories in Tanzania were analysed. These represented 8 regions providing 94 laboratory-years of work; 61,580 tuberculosis suspects were evaluated with the aid of 141,371 smears. The average proportion of cases found among suspects was 18.9% (range 14.3-23.8% in the 8 regions). The number of cases missed among suspects with incomplete examinations was calculated based on the number observed among suspects with a complete set of 3 smears examined, and an incremental yield of 83.4% with the first, 12.2% with the second, and 4.4% with the third smear was estimated for the total number of expected cases. These data suggest that (i) the method frequently employed for calculating requirements for laboratory supplies in low income countries, based on the estimate that 10 suspects need examination to identify one case of sputum smear-positive tuberculosis, is generous in the context of Tanzania and (ii) under routine conditions the incremental yield from a third smear examination after 2 negative examinations is relatively small.
对坦桑尼亚34个实验室痰涂片抗酸杆菌直接检查的常规结果进行了分析。这些实验室代表8个地区，提供了94个实验室年的工作量；借助141,371份涂片对61,580名结核病疑似患者进行了评估。在疑似患者中发现的病例平均比例为18.9%（8个地区的范围为14.3%-23.8%）。根据对全套3份涂片检查的疑似患者中观察到的病例数，计算了检查不完整的疑似患者中漏诊的病例数，并估计了预期病例总数中首次涂片的增量检出率为83.4%，第二次涂片为12.2%，第三次涂片为4.4%。这些数据表明，（i）在坦桑尼亚的情况下，低收入国家常用的根据估计10名疑似患者需要检查才能确诊1例痰涂片阳性结核病来计算实验室用品需求的方法是宽松的，以及（ii）在常规条件下，2次阴性检查后第三次涂片检查的增量检出率相对较小。
