Acute kidney injury in allopurinol-induced DRESS syndrome: A case report of concurrent tubulointerstitial nephritis and kidney-limited necrotizing vasculitis

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a rare but potentially fatal adverse drug reaction with variable renal involvement. We report the case of a man who presented with allopurinol-induced DRESS and acute kidney injury (AKI) requiring hemodialysis. Kidney biopsy revealed eosinophilic tubulointerstitial nephritis and necrotizing vasculitis of the intralobular arteries without systemic markers of vasculitis. After cyclophosphamide and glucocorticoids, his symptoms and AKI resolved. To our knowledge, this is the first case of kidney-limited necrotizing vasculitis, questioning whether a biopsy should be routinely performed in patients with DRESS accompanied by severe AKI. It is possible that kidney-limited necrotizing vasculitis is an under-diagnosed manifestation of DRESS syndrome, and in such a setting, early recognition, stopping the offending agent, and use of aggressive immunosuppressive therapy, including cyclophosphamide, may lead to a favorable outcome.