Cutaneous polyarteritis nodosa in a patient with Crohn's disease.

A 19-year-old Japanese woman with a 4-year history of Crohn's disease (CD) developed high fever, polyarthralgia, and painful subcutaneous nodules of the legs. A skin biopsy showed panarteritis with fibrinoid necrosis in the deep dermis. Endoscopic examination showed aphthous lesions in the entire colon. She was diagnosed with cutaneous polyarteritis nodosa (PAN) associated with CD. Steroid therapy improved her symptoms. To our knowledge, this is the first Japanese case of cutaneous PAN associated with CD.