Mycobacterium tuberculosis infection precipitates SLE in patients from endemic areas.

In a cohort of 70 systemic lupus erythematosus (SLE) patients diagnosed over 2 years period, 14 patients were found to have confirmed antecedent tuberculosis (20.0%) which was 40 times higher (p < 0.001, 95%CI 36.2-48.6) than the prevalence of tuberculosis in the local population. Demonstration of anti-histone antibodies in similar proportion of SLE patients with and without antecedent anti-TB treatment and similar proportion of renal involvement (36 vs. 40%) between anti-TB drug exposed and non-exposed patients ruled out the drugs to be causative factors in precipitating SLE in these patients with antecedent history of tuberculosis. A cohort of 30 confirmed pulmonary tuberculosis patients were also studied in parallel to demonstrate high incidence of autoantibodies in these patients but no SLE. This study suggests a role of prior tuberculosis in precipitating SLE in genetically predisposed patients.