Crohn's disease and Sweet's syndrome: an uncommon association.

Sweet's syndrome or acute febrile neutrophilic dermatosis (SS) is characterized by the sudden onset of painful erythematous lesions (papules, nodules, and plaques) together with fever and neutrophilia. The lesions are typically located on hands, arms, upper trunk, neck and face, showing an asymmetric distribution. Acute phase reactants are usually elevated and dermal infiltration of neutrophils without vasculitis is seen on skin biopsies. It is considered as a marker of systemic disease in over half of the cases, and is associated with infections, inflammatory bowel disease, autoimmune connective tissue disorders and various neoplasias. Its association with Crohn's disease (CD) is unusual and it appears mainly in association with colonic involvement. Fewer than 50 cases have been published in the medical literature since its first description in 1964, some concurrent with the first episode of CD. We present two patients with Crohn's disease and Sweet's syndrome diagnosed in our department at the time of CD diagnosis, as well as their response to treatment, subsequent course of the disease, and a review of the scientific literature.