Crohn's Disease of the Ileal Pouch 16 Years After Proctocolectomy for Ulcerative Colitis

This 34-year-old man is referred to our institution for possible Crohn’s disease. He was diagnosed with ulcerative colitis at age 6 years. His disease was eventually refractory to medical therapy, and he underwent a 2-stage proctocolectomy with ileal J-pouch to anal sewn anastomosis and temporary ileostomy at age 17 years. After takedown of the ileostomy his bowel function stabilized, with 6 stools daily with abdominal cramping pain, fecal urgency, and smallvolume nocturnal fecal incontinence. He had minimal improvement in symptoms with alternating courses of metronidazole and ciprofloxacin. Pouch endoscopy at age 33 showed multiple pouch ulcers. The anti–Saccharomyces cerevisiae antibodies (ASCA) and the perinuclear antineutrophil cytoplasmic antibody (p-ANCA) were negative. He had temporary relief of symptoms with courses of prednisone 20 mg daily, with recurrence after discontinuation. He developed postprandial abdominal cramping pain, abdominal distention, and nausea that gradually worsened and was not relieved by prednisone 40 mg daily. He did not improve with azathioprine. He developed severe bronchospasm during initial infusion of infliximab, and it was discontinued. At the time of referral he appears about 5 kg below ideal weight. The pouch-anal anastomosis is normally patent. Pouch endoscopy reveals multiple deep ulcers in the pouch and ulcers and narrowing of the lumen in the pre-pouch ileum (Figure 1), and biopsies show nonspecific ileitis. A contrast pouchogram shows a fistula from the pouch to the proximal ileum and a stricture in the pre-pouch ileum, with dilatation of the more proximal ileum (Figure 2). He undergoes abdominal exploration; there is a tight stricture at the junction of the pre-pouch ileum and the proximal pouch, and the distal 20 cm of the pre-pouch ileum is markedly dilated. There is a tight stricture in the midpouch, and the proximal pouch is very large. The pouch is disconnected from the anus and reduced in size. Two strictureplasties are performed, and the pouch is reanastomosed to the anus, and a temporary diverting ileostomy is placed. Azathioprine and adalimumab are started. The temporary ileostomy is taken down after 6 months. At 2 years after his most recent surgery, he reports about 6 stools daily, with rare nocturnal fecal incontinence and daily mild abdominal cramping pain. He continues on azathioprine and adalimumab. Pouch endoscopy shows scattered superficial ulcers in the pouch, with a normal pre-pouch ileum. Laboratory studies including C-reactive protein are normal (Figure 3). Case Discussion Despite advances in diagnostic methods during the past 30 years, there remains uncertainty in differentiating ulcerative colitis from Crohn’s disease of the colon in about 10% of patients. This subset of colitis has been termed indeterminate colitis, and more recently the term inflammatory bowel disease unclassified (IBDU) has been proposed. In a European multicenter study of 97 patients with indeterminate colitis as defined by clinical, radiographic, endoscopic, and histologic criteria, 48.5% were negative for both ASCA and p-ANCA. After a mean follow-up of 9.9 years, only 14.9% of those patients with IBDU who were ASCA and p-ANCA negative developed Crohn’s disease (as did the patient in this case discussion) or ulcerative colitis compared with 48% of patients with a positive serology, with ASCA/p-ANCA as a predictor of Crohn’s disease and ASCA/p-ANCA as a predictor of ulcerative colitis. This patient most likely had Crohn’s disease from the onset, with recurrence in the ileal pouch and pre-pouch ileum after colectomy and pouch anal anastomosis. It was not possible to determine by endoscopy whether inflammatory changes limited to the pouch were due to idiopathic pouchitis or to Crohn’s disease. Pouch biopsies occasionally show noncaseating granulomas, indicative of Crohn’s disease, but this is the exception, and no granulomas were found on biopsies in this patient. There was a pouch to ileal fistula as well as ulceration and stenosis in the pre-pouch ileum; these are hallmarks of Crohn’s disease and are not features of idiopathic pouchitis. The patient had minimal improvement with metronidazole and ciprofloxacin, and this is atypical for patients with idiopathic pouchitis, because a majority responds favorably to antibiotics. Failure to achieve an acceptable symptomatic improvement with antibiotics raises the possibility of another etiology for the pouch inflammation, such as Crohn’s disease as in the case of this patient, or obstruction for a