Biological agents are widely used for various immune-mediated diseases, with
remarkable effectiveness in the treatment of rheumatoid arthritis (RA), psoriasis,
psoriatic arthritis, ankylosing spondylitis and Crohn's disease. However, attention
needs to be drawn to the adverse effects of these therapies and the risk of
reactivating underlying granulomatous infectious diseases such as tuberculosis,
leprosy, syphilis, leishmaniasis, among others. The objective of this paper is to
describe a case of leprosy in a patient with RA using anti-TNF alfa, demonstrating
the need for systematic investigation of skin lesions suggestive of leprosy in
patients who require rheumatoid arthritis therapeutic treatment, especially in
endemic regions like Brazil.