Abstract
Acute interstitial nephritis (AIN) is a common cause of acute kidney injury and renal failure. It is typically drug induced but can also be idiopathic or secondary to chronic infective or inflammatory conditions. Recent case reports suggest vedolizumab can be a causative agent for AIN. We report the case of a young man who presented with renal failure, fevers and constitutional symptoms. He had a complex history of refractory ulcerative colitis, prior colectomy and ileo-pouch-anal anastomosis with recurrent pouchitis. He had been receiving regular vedolizumab infusions for 6 months by the time of his presentation. A renal biopsy 4 months into his follow-up demonstrated AIN. Steroid prophylaxis with vedolizumab was trialled but ultimately failed, with worsening AIN and incomplete renal function recovery. To our knowledge, this is the first case of vedolizumab-induced AIN demonstrating a failure of steroid prophylaxis to prevent recurrence of AIN following vedolizumab rechallenge.