Autoimmune Hemolytic Anemia From Tofacitinib Use in a Patient With Ulcerative Colitis.

Tofacitinib is a Janus kinase inhibitor commonly used in the management of rheumatoid arthritis and moderate-to-severe ulcerative colitis. Anemia is a rare side effect of this medication often with minimal changes in hemoglobin levels. We report the first case of autoimmune hemolytic anemia from tofacitinib use in a patient with inflammatory bowel disease. This patient developed transfusion-dependent anemia after the initiation of tofacitinib and underwent extensive workup that revealed a diagnosis of autoimmune hemolytic anemia. The medication was discontinued, and she was treated with steroids and rituximab, leading to the improvement and stabilization of her hemoglobin levels.