Starving Colon: A Rare Cause of Colitis in a Patient With a Diversion Ileostomy

Abstract

Introduction An uncommon complication of bowel diversions presents as inflammation of the non-functioning, bypassed segment known as diversion colitis and is difficult to distinguish from other causes of colitis. Because diversion results in a deficiency of short-chain fatty acids (SCFAs) and other nutrients, the suspected pathogenesis likely results from alteration of mucosal cytokines and changes in the gut flora and metabolism. Case Description A 61 year old female with a prior history of perforated diverticulitis complicated by recurrent abscesses status-post Hartmann's procedure presented with worsening nausea, vomiting, and episodes of bloody diarrhea. Previously, she underwent a colostomy takedown, but a diversion ileostomy was required due to concern for a peri-rectal leak. Abdominalexam demonstrated diffuse tenderness with normoactive bowel sounds. Ileostomy had brown stool with some blood present. Laboratory analysis revealed a HGB of 7.7 g/dl, MCV of 75.1 fl, and negative stool studies. Abdominal computed tomography showed new diffuse colonic wall thickening suggesting colitis. Further work up revealed a high ANCA titer and positive ASCA IgG antibodies. A colonoscopy showed active enteritis in the terminal ileum and evidence of pancolitis, endoscopically, concerning for IBD. Biopsies were nonspecific, but displayed acute inflammation without evidence of viral infection. Prior colonoscopies were negative for findings of IBD. It was clinically determined that the etiology was likely diverting colitis based on clinical history with improvement after surgical reanastomosis. Discussion The incidence of diversion colitis is unclear and only documented in small studies. Endoscopy often shows non-specific inflammatory changes including erythema and friability of the mucosa with histology often non-diagnostic. Interestingly, previous studies suggest that diversion colitis arise more often in patients with a history of IBD. There has been no reported case to our knowledge of diversion colitis in a patient with diverting ileostomy, which ultimately recovered after integrity of the bowel was restored. Definitive treatment requires reanastomosis in symptomatic patients. If repair cannot be performed, then SCFAs enemas or 5-aminosalicyclic acid can be utilized. Early recognition and considering the diagnosis of diversion colitis in patients with segment diversions can allow appropriate management when evaluating colitis.