P089 Small bowel Clostridium difficile masquerading as Crohn's disease

Abstract

CASE: A 38-year old man with a history of perforated diverticulitis s/p sigmoid colectomy presented to the emergency room with 2 days of abdominal pain. He was without any symptoms of diarrhea, hematochezia or melena. He was previously admitted to the hospital for 4 days approximately one month prior to presentation with similar symptoms of abdominal pain. He had a CT scan of the abdomen and pelvis performed during that admission with wall thickening of the terminal ileum, but no colonic inflammation seen. He was treated with a week of ciprofloxacin and metronidazole with transient improvement in his symptoms. He denied any significant social history. Family history was negative for inflammatory bowel disease. He denied any NSAID use, but he did report a 3-day course of clindamycin approximately 3 weeks ago for a dental procedure. His lab values were notable for a mild leukocytosis of 12.6 × 109/L (ref range 4.8–10.8 × 109/L), elevated C-reactive protein at 1.89 mg/dL (ULN ≤ 0.60 mg/dL), normal lactate at 1.0 mmol/L (ref range 0.6–2.2 mmol/L), and a negative QuantiFERON TB Gold Plus. He had CT imaging repeated of his abdomen and pelvis that was significant for multiple loops of ileal wall thickening consistent with severe ileitis without any inflammation of the large intestine. Given the concern for Crohn's disease, a colonoscopy was performed and a normal terminal ileum was seen for 30 cm. There were multiple small-mouth diverticula seen in the descending, transverse and ascending colon along with a prior end-to-end colo-colonic anastomosis in the sigmoid colon. The mucosa appeared to be normal and healthy in the colon. Random biopsies taken of the terminal ileum and colon were negative for any significant pathological diagnosis. No antibiotics were given prior to colonoscopy. Stool studies returned with a positive Clostridium difficile result, but negative stool culture and parasite screen. He was treated with a 14-day course of metronidazole 500 mg Q8H with resolution of his symptoms. DISCUSSION: This case is atypical given the patient's lack of significant diarrhea, CT imaging findings of distal ileal involvement without any colonic inflammation, and normal findings on both endoscopic evaluation and pathology. While C. difficile is the most common cause of healthcare associated infectious diarrhea, small bowel infection with C. difficile is a rare presentation. The pathophysiology of C. difficile enteritis is not well understood, but most cases reported in the literature have been described in patients with altered bowel anatomy such as colectomy, pouch construction or other large and small bowel surgery. In these cases, the small bowel is postulated to be more susceptible to colonization and infection in the setting of surgical intervention. This case highlights that C. difficile can solely affect the small bowel of patients with limited colonic resections which is important for practicing gastroenterologists.