Systemic lupus erythematosus (SLE) induced by quinidine.

Only two definite cases of quinidine-induced systemic lupus erythematosus (SLE) are reported in the English-language literature. We have treated five patients who had an SLE-like syndrome while receiving quinidine. Symptoms, signs, and abnormal laboratory values improved after quinidine therapy was discontinued and prednisone therapy was started. The disease did not return after steroids were withdrawn. These cases indicate that quinidine can indeed cause an SLE-like syndrome.