Ulcerative colitis and Sweet's syndrome: a case report and review of the literature.

A 47-year-old man with a history of ulcerative colitis on prednisone and azathioprine was admitted to the hospital with a four-day history of fever, skin rash, arthralgias and leukocytosis. A skin biopsy demonstrated neutrophilic infiltration of the dermis that was consistent with Sweet's syndrome. He improved after several days with an increase in his prednisone and azathioprine. Sweet's syndrome is a rare cutaneous manifestation of inflammatory bowel disease, with approximately 40 cases reported in the literature. In a previously reported case of a patient with ulcerative colitis-associated Sweet's syndrome who was on azathioprine at the time of the skin eruption, the azathioprine was stopped, raising the possibility of drug-induced Sweet's syndrome. In the present case, the azathioprine was actually increased with complete resolution of the skin manifestations. This would support the theory that immunosuppressive therapy is the mainstay of therapy for this condition. In conclusion, Sweet's syndrome is a neutrophilic dermatosis that is rarely associated with ulcerative colitis. It may occur while on immunosuppressive therapy and responds to an intensification of immunosuppression.