[Development of systemic lupus erythematosus after thymectomy performed in a patient with myasthenia gravis].

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease, with not fully understood, complex origin. Several factors are suspected of involvement in the development of the disease. Genetic predisposition, environmental factors, some drugs, estrogens, cigarette smoking and ultra violet radiation seems to be the most important among them. The case of a patient with myasthenia gravis (MG) followed by thymectomy and lupus erythematosus (SLE) diagnosed one year later presented in this study.