Secondary Eosinophilic Colitis Obscuring the Diagnosis of Crohnʼs Disease

Abstract

A 30 year-old male presented with a 3-month history of abdominal pain, nausea, vomiting, diarrhea, bleeding per rectum, and weight loss. He was hospitalized with similar symptoms at another facility 3 weeks ago where he was diagnosed to have ulcerative colitis based on colonoscopy and was treated with steroids. He had some improvement but after his medication ran out, his symptoms began to worsen. On admission, he had leukocytosis and stool Clostridium difficile toxin was positive while all other stool studies were negative. CT scan of the abdomen/pelvis showed inflammation in the terminal ileum and cecum. Colonoscopy revealed an ulcerated proliferative mass with multiple polyploid lesions nearly occluding the lumen in the proximal ascending colon and cecum, scattered aphthoid ulcers in the rectum and normal intervening colonic mucosa. Biopsy of the cecal lesion showed focal architectural distortion, acute and chronic inflammation with marked eosinophilic infiltration and absence of granulomas. Rectal biopsy showed mild inflammation and random biopsies of the intervening colon mucosa were normal. Patient was treated with oral metronidazole for 10 days without improvement in symptoms even though repeat stool C. diff toxin was negative. Mesalamine was started for presumed inflammatory bowel disease (IBD) resulting in minimal improvement. A CT enterography was then performed and showed severe bowel wall thickening and mucosal enhancement in the cecum, proximal ascending colon and terminal ileum, and a possible fistula tract between the cecum and ascending colon. Thereafter, IV methyl prednisolone was started with consequent rapid improvement in symptoms. He was then discharged home on a 2 month slow taper of prednisone and sulfasalazine. Eosinophilic colitis is a diagnosis of exclusion with a wide differential for the etiology. Although no granulomas were seen on the colon biopsies, the focal architectural distortion, colo-cecal fistula on imaging, and improvement with steroids suggested Crohn's disease over idiopathic eosinophilic colitis or ulcerative colitis. Incidentally, gASCA (anti-Saccharomyces cerevisiae antibody) levels were high (163 units), highly indicative of Crohn's disease over ulcerative colitis. The association between IBD and mucosal eosinophilia has been increasing, although the pathophysiology is unknown; but in a patient like ours the clinical suspicion for IBD, particularly Crohn's disease, must remain high.Figure 1Figure 2Figure 3