Abstract

IgA vasculitis (also known as Henoch-Schonlein purpura) is an inflammation of the small blood vessels in the skin, gastrointestinal tract and the kidneys. It has been rarely reported to occur concomitantly in patients with Crohn’s disease and as adverse reaction to TNF inhibitors. Herein we report a case of 19-year-old male patient with Crohn's disease on infliximab who presented with progressive abdominal pain, polyarthralgia and was found to have a purpuric rash, leukocytosis, and proximal colonic thickening on CT scan. He was admitted for evaluation of possible vasculitis. Histopathological examination of a skin lesion on the thigh revealed re-epithelializing blister with necrosis of the roof and an underlying superficial and deep perivascular dermatitis consisting mostly of lymphocytes and numerous eosinophils. Direct immunofluorescence showed deposits of IgA and fibrin in the blood vessels of the papillary dermis. Granular deposits of IgM and IgM cytoid bodies were detected along the basement membrane zone. The patient was administered steroids which led to complete resolution of symptoms. Our case should prompt clinicians and pathologists to consider IgA vasculitis in the differential diagnosis of purpura in patients with Crohn’s disease and initiate appropriate treatment.

Financial Disclosure:
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