Granulomatous vasculitis in Crohn's disease: a clinicopathologic correlate of two unusual cases

Cutaneous complications occur not uncommonly in patients with Crohn's disease (CD). Gastrointestinal CD often shows non-caseating granulomas and a rare cutaneous finding in CD is a sterile granulomatous infiltrate not contiguous with the GI tract, termed extraintestinal CD (ECD). The clinical presentation of ECD is diverse. The most common histopathological presentation is a superficial and deep granulomatous infiltrate that often accompanies a mixed perivascular infiltrate. Here we report two patients with CD and skin lesions characterized on microscopy by granulomatous vasculitis. A 29-year-old female presented with papules and ulcerated nodules above the ankle. The biopsy showed dermal and superficial subcutaneous involvement by a vasocentric infiltrate of mononuclear and multinucleated histiocytes as well as mural fibrin deposition. A 35-year-old male presented with two tender indurated erythematous plaques with punched-out centers on the lower leg. Histopathologically, a granulomatous vasculitis of small and medium-sized vessels in the dermis and subcutis was evident. These two cases represent the rarely described phenomenon of cutaneous granulomatous vasculitis in CD. Previously reported examples of this entity are reviewed.