The mask of acute bacterial pneumonia may disguise the face of tuberculosis

INTRODUCTION: Pulmonary tuberculosis (TB) can present as acute pneumonia. Differentiation of tuberculous from non-tuberculous community-acquired pneumonia (CAP) is an important challenge in endemic areas. The purpose of this study was the comparison between characteristics of tuberculous and non-tuberculous CAP patients. METHODS: In this prospective and observational study, all adult patients (aged ≥16 years) who were admitted to Imam Reza Hospital in Mashhad (Iran) with the diagnosis of CAP, between February 2013 and January 2014, were enrolled. Clinical, radiological, and microbiological data of the patients were collected and reviewed. Statistical analyses were performed using SPSS 14 software and R programming language. RESULTS: We studied 120 patients with diagnosis of acute CAP including 21 (17.5%) tuberculous and 99 (82.5%) non-tuberculous CAP. The etiologies of CAP in the latter group were as follow: S. pneumoniae 29 (29.3%), followed by S. aureus, polymicrobial including anaerobes, and other agents. The diagnosis of pneumonia remained unknown in 49 (40%) patients. We found approximately equal gender distribution among two study groups (14/21 vs. 61/99, 63.6% vs. 62.9%, p=0.948). Fifty percent of patients with tuberculous CAP had opioid addiction that was more frequent compared with non-tuberculous group (p=0.240). 52.4%, 63.2%, 30%, and 90% of patients with tuberculous CAP had severe presentation based on PSI, IDSA/ATS, CURB-65, and SMART-COP, respectively. CONCLUSIONS: The diagnosis of TB should be considered in all patients who presented with CAP in endemic regions. It could not be differentiated from other causes of pneumonia on clinical and radiological grounds.