Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Chung-Ang University School of Medicine, Seoul, Korea.
Respiration. 2010;79(6):454-60. doi: 10.1159/000277926. Epub 2010 Jan 21.
Early diagnosis of active pulmonary tuberculosis (PTB) is critical for TB control, and difficult in patients with smear-negative sputum.
We wanted to evaluate the usefulness of clinical findings, high-resolution computed tomography (HRCT), interferon-gamma-releasing assay (IGRA) and polymerase chain reaction (PCR) of sputum in the diagnosis of smear-negative PTB.
From June 2006 to September 2008, 178 patients with suspected PTB on the basis of clinical and radiological findings visited our institute. After excluding smear-positive cases (n = 77) and cases with an inconclusive diagnosis (n = 17), we studied 84 patients. Their clinical records, HRCT, sputum TB-PCR assay and IGRA results were retrospectively evaluated. A QuantiFeron-TB Gold (QFT-G; Cellestis Ltd., Carnegie, Vic., Australia) assay was used for the IGRA.
Active PTB was diagnosed in 40 (48%) of 84 patients; lack of sputum and young age were significantly associated with an increased risk of PTB. The sensitivities of sputum PCR assay, IGRA, and HRCT were 43.2, 84.4 and 80.0%, respectively, and the specificities were 97.7, 82.9 and 70.5%, respectively. Among the 38 patients suspected of having PTB based on HRCT, 24 patients showed positive results on the IGRA, and 23 of these were diagnosed with active PTB. Among the 35 patients suggested not to have TB based on HRCT, 25 showed negative results on the IGRA, and 23 (92%) of these were diagnosed as not to have TB.
The combined results of HRCT and the IGRA could help decision-making for early initiation of treatment in smear-negative patients.
早期诊断活动性肺结核（PTB）对于结核病控制至关重要，但在痰涂片阴性的患者中较为困难。
我们旨在评估临床发现、高分辨率计算机断层扫描（HRCT）、γ干扰素释放试验（IGRA）和痰聚合酶链反应（PCR）在诊断痰涂片阴性 PTB 中的作用。
2006 年 6 月至 2008 年 9 月，根据临床和影像学表现，我们机构共收治了 178 例疑似肺结核患者。排除痰涂片阳性病例（n=77）和诊断不明确病例（n=17）后，我们对 84 例患者进行了研究。回顾性评估了他们的临床记录、HRCT、痰 TB-PCR 检测和 IGRA 结果。使用 QuantiFeron-TB Gold（QFT-G；Cellestis Ltd.，Carnegie，Vic.，Australia）检测用于 IGRA。
84 例患者中确诊活动性 PTB 40 例（48%）；无痰和年龄较轻与 PTB 风险增加显著相关。痰 PCR 检测、IGRA 和 HRCT 的灵敏度分别为 43.2%、84.4%和 80.0%，特异性分别为 97.7%、82.9%和 70.5%。在 38 例根据 HRCT 怀疑患有 PTB 的患者中，24 例 IGRA 结果阳性，其中 23 例诊断为活动性 PTB。在根据 HRCT 提示无结核的 35 例患者中，25 例 IGRA 结果阴性，其中 23 例（92%）诊断为无结核。
HRCT 和 IGRA 的联合结果有助于在痰涂片阴性的患者中尽早开始治疗决策。
