Sulfasalazine-induced lupus syndrome in a patient with Crohn's disease.

The case is described of a young woman with Crohn's disease of the rectum and terminal ileum in whom systemic lupus erythematosus syndrome was diagnosed after 3 yr of symptoms and 4 yr treatment with sulfasalazine. Polyarthralgias and pleuritic chest pains resolved and leucopenia, anemia, and high titers of antinuclear and DNA antibodies returned to normal after withdrawal of the drug. No HLA antigen association was found but a slow acetylation phenotype was present. Consideration should be given to this complication of sulfasalazine therapy in patients with inflammatory bowel disease in whom arthropathy or other features of lupus syndrome appear after treatment is instituted.