Can lupus flares be associated with tuberculosis infection?

Systemic lupus erythematosus (SLE) is an autoimmune disease that frequently requires treatment with high doses of corticosteroids and immunosuppressive drugs. Primary defects in the innate immunity also contribute to an increased susceptibility to infections. Patients with SLE are at an increased risk for infections with several pathogens, among them Mycobacterium tuberculosis, which is a significant cause of morbidity and mortality, especially in endemic regions. TB infection requires awareness for several reasons: first, TB infection thrives under conditions of immunosuppression, may it be secondary to the disease itself or its treatment. Second, shared antigens by mycobacteria and autoantigens have been described, which may be targets for autoantibodies. We present four Brazilian patients, in whom a diagnosis of tuberculosis was determined during or following persistent flares of their disease. The association of SLE and TB is discussed, as well as different aspects of the tuberculosis infection in this selected population, and its possible role in the course of SLE.