Clinical spectrum of active tuberculosis in patients with systemic lupus erythematosus

Abstract

Introduction: There is paucity of data on tuberculosis in Indian patients with systemic lupus erythematosus (SLE). We retrospectively studied clinical features and outcome of tuberculosis in SLE. Methods: Medical records of patients who developed tuberculosis simultaneous or after the diagnosis of SLE were retrospectively reviewed. All patients fulfilled 1997 ACR and/or SLICC 2012 classification criteria for SLE. A diagnosis of tuberculosis required bacteriological, histopathological or CT/MRI suggestive of tuberculosis and initiation of four drug antituberculous therapy. Baseline parameters were compared with the rest of cohort to identify predictors of tuberculosis. Results: In our cohort of 1335 SLE patients, 48 (3.6%) developed tuberculosis. Incidence of tuberculosis was calculated to be 733 per 100,000 patient years and occurred after a mean disease duration of 3.0 ± 4.1 years. Extrapulmonary tuberculosis (n = 37) was commoner than pulmonary tuberculosis (n =11). Most common radiological pattern in pulmonary tuberculosis was miliary and musculoskeletal TB was most common extrapulmonary TB. A microbiological diagnosis was obtained in 52.1% patients. Male gender was associated with higher risk of tuberculosis [OR 3.30 (1.55-7.05)]. Mortality was 14.5% and all patients who died had either disseminated (n = 5) or central nervous system (CNS) tuberculosis (n = 2). Conclusion: Incidence of tuberculosis in SLE is higher than general population and is associated with different phenotype and higher mortality. Male gender was associated with increased risk of tuberculosis in SLE.