Data from: Characteristics of patients with smear-negative pulmonary tuberculosis (TB) in a region with high TB and HIV prevalence

Introduction: Smear-negative pulmonary TB (SNPT) represents 30–60% of all pulmonary TB cases. The mortality of these patients can reach 25% in populations with high prevalence of HIV infection, and 10–20% of TB transmission at the population level are attributable to SNPT cases. Methods: We conducted a retrospective study to evaluate epidemiological, clinical, and radiological characteristics of patients with SNPT and to compare these with patients who were diagnosed as having smear-positive pulmonary TB (SPPT). All adult patients (≥ 18 years old) with a positive culture for Mycobacterium tuberculosis, and a diagnosis of pulmonary TB were included in the study. Results: 198 patients met the inclusion criteria (positive culture for Mycobacterium tuberculosis) and were included in the analysis. Of these patients, 69 (34.8%) were smear positive (SPPT) and 129 (65.2%) were smear negative (SNPT). In univariate analysis, cough, dyspnea, and hemoptysis were less frequent in SNPT patients in comparison with SPPT patients. In a multivariate model, having no cough and no radiographic pattern typical of TB were the characteristics independently associated with a diagnosis of SNPT. Conclusions: We found a very high prevalence of SNPT among patients with TB in a setting with high TB and HIV prevalence. The absence of cough in the presence of other symptoms suggestive of TB, and having no radiographic pattern typical of TB where independent predictors of SNPT.

引言：涂片阴性肺结核（Smear-negative pulmonary TB, SNPT）占所有肺结核病例的30%~60%。在HIV感染高流行人群中，此类患者的病死率可达25%，而人群层面10%~20%的结核传播可归因于涂片阴性肺结核病例。
方法：本研究开展回顾性分析，旨在评估涂片阴性肺结核患者的流行病学、临床及影像学特征，并与确诊为涂片阳性肺结核（Smear-positive pulmonary TB, SPPT）的患者进行对比。本研究纳入所有结核分枝杆菌培养阳性、确诊为肺结核的成年患者（年龄≥18岁）。
结果：共计198例符合纳入标准（结核分枝杆菌培养阳性）的患者被纳入分析。其中69例（34.8%）为涂片阳性肺结核患者（SPPT），129例（65.2%）为涂片阴性肺结核患者（SNPT）。单因素分析显示，与SPPT患者相比，SNPT患者的咳嗽、呼吸困难及咯血症状发生率更低。多因素模型分析显示，无咳嗽症状及无典型肺结核影像学表现是与SNPT诊断独立相关的特征。
结论：本研究发现，在结核与HIV均呈高流行的地区，肺结核患者中涂片阴性肺结核的患病率极高。当患者存在其他提示肺结核的症状但无咳嗽，且无典型肺结核影像学表现时，上述两项特征可作为涂片阴性肺结核诊断的独立预测因素。