In recent decades there has been an increase in the number of breast implants for reconstruction and cosmetic purposes. Infection is a severe complication mostly caused by Staphylococcus aureus or coagulase-negative staphylococci. Mycobacteria are an infrequent cause of infection in this type of surgery. We describe a case of Mycobacterium fortuitum infection in a patient with lupus, subjected to a prosthetic replacement. These patients are more prone to unusual opportunistic infections. Treatment always requires both removal of prosthetic material and antibiotic therapy.