A Case of “Refractory” Crohn's Disease

2011

Question: A 48-year-old man presented to the emergency department with sudden onset of central abdominal pain, vomiting, and collapse. There was no history of altered bowel habit and he had no previous similar episodes. On examination, he had generalized abdominal tenderness. Initial investigations showed a raised white cell count of 18.1 x 109/L, a raised plasma C-reactive protein concentration of 22 mg/L, and a raised platelet count of 509  103/mm3. All other blood tests were unremarkable.

Initial abdominal x-ray showed mild small bowel dilatation and a computed tomography (CT) scan of the abdomen was subsequently performed (Figure A). This showed an area of small bowel wall thickening in the terminal ileum, suggestive of Crohn's disease. He was commenced on prednisolone and Pentasa, which resulted in resolution of his symptoms and was discharged 4 days later. He represented a week later with similar symptoms and therefore a colonoscopy was performed (Figure B) with biopsies of the terminal ileum (Figure C).

Answer to the Clinical Challenges and Images in GI Question: Image 6:
Small Bowel Adenocarcinoma Figure B showed an inflamed and ulcerated terminal ileum on colonoscopy. Biopsies from this (Figure C) revealed that in addition to changes suggestive of Crohn's disease; there was an area of moderate to poorly differentiated
adenocarcinoma. This patient underwent a right hemicolectomy and the resected pathologic specimen also showed fissuring ulceration and active inflammation consistent with Crohn’s disease. He is currently undergoing adjuvant chemotherapy.

Inflammatory bowel disease is linked to large and small bowel malignancies, especially adenocarcinoma. It is very rare for patients to present with small bowel adenocarcinoma at the time of diagnosis with Crohn’s disease. Small bowel adenocarcinoma develops in 2.2% of patients who have long-standing Crohn’s disease although it is seldom diagnosed preoperatively because of its rarity.1 First observations suggest that those at risk of developing small bowel adenocarcinoma were patients who had surgical bypass procedures of bowel segments secondary to inflammatory bowel disease. The risk of small bowel carcinoma in patients with Crohn’s disease is thought to be between 12- and 60-fold of that in the general population.2 Small bowel adenocarcinoma is often diagnosed post-operatively and in areas of strictures.3 Risk factors for small bowel adenocarcinoma in Crohn's disease are chronic active course with stricture, fistulae, and onset of disease before the age of 30 years. Occult small bowel adenocarcinoma developing in areas of strictures poses a diagnostic challenge. Computed tomography is currently the preferred choice for imaging. Magnetic resonance imaging, double contrast enteroclysis, small bowel enteroscopy, and capsule endoscopy are promising new diagnostic tools.

Small bowel adenocarcinoma is rare in patients with Crohn’s disease, but clinicians should have a high index of suspicion, especially in patients who are refractory to initial conventional medical treatment. This case illustrates the importance of performing terminal ileoscopy during colonoscopy to obtain biopsies in patients with intractable Crohn’s disease. Figure D.

References

  1. Tougeron D, Lefebure B, Savoye G, et al. Small-bowel adenocarcinoma in patient with Crohn’s disease: report of a series of three cases. Scand J Gastroenterol 2008;43:1397–1400.
  2. Jess T, Winther KV, Munkholm P, et al. Intestinal and extra-intestinal cancer in Crohn's disease: follow-up of a population-based cohort in Copenhagen County, Denmark. Aliment Pharmacol Ther 2004;19:287–293.
  3. Partridge SK, Hodin RA. Small bowel adenocarcinoma at a strictureplasty site in a patient with Crohn's disease: report of a case. Dis Colon Rectum 2004;47:778 –781.