Leprosy is clinically characterized by involvement of peripheral nerves and skin. The immunological profile of the individual defines the diversity of clinical manifestations, from skin disorders to systemic manifestations, especially the articulation ones, common in multibacillary forms, which may mimic collagen diseases and often posing diagnostic difficulties in endemic areas. This is a case report of asymmetric polyarthritis of small and large articulations associated with skin lesions which had been treated by a rheumatologist for 2 years with initial clinical diagnosis of rheumatoid arthritis, and later, with the appearance of skin lesions, of systemic lupus erythematosus.