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.