The diagnosis of Crohn's disease in patients who have undergone ileal pouch-anal anastomosis (IPAA) surgery for ulcerative colitis or indeterminate colitis can be difficult.
However it is important for prognostic and therapeutic purposes, write researchers at the Centre for Inflammatory Bowel Disease at the Cleveland Clinic Foundation in Cleveland, Ohio, USA.
They studied 87 patients who had undergone IPAA for inflammatory bowel disease in an attempt to identify diagnostic features of Crohn's disease in such patients.
Study subjects were classified as having ulcerative colitis (n = 28), Crohn's disease (n = 27), or indeterminate colitis (n = 32). Classifications were made following review of the original colectomy pathology and postoperative clinical course.
| Afferent limb ulcers were identified in 45% of patients with Crohn's disease|
| Gastroenterology |
Each patient underwent a pouch endoscopy with biopsies of the pouch and afferent limb. In all the cases both the endoscopist and the pathologist were blinded to the diagnosis that each patient had been given.
Afferent limb ulcers were identified on endoscopy in 12 of 27 patients with Crohn's disease (45%). A further 4 of 28 patients (14%) with ulcerative colitis were also found to have afferent limb ulcers.
Following exclusion of those patients who had taken nonsteroidal anti-inflammatory drugs (NSAIDs) within the past month, afferent limb ulcers were present in 7 of 18 patients with Crohn's disease (37%) and 0 of 17 patients with ulcerative colitis.
The researchers then controlled for both NSAID use and smoking. This produced an odds ratio for afferent limb ulcers of 4.67.
In the case of ulcerative colitis patients, 4 of 11 patients (36%) who had taken NSAIDs in the past month, and 0 of 17 who had not taken NSAIDs, were found to have afferent limb ulcers.
The researchers end by concluding that for those who are not taking NSAIDs, afferent limb ulcers seen on endoscopy are suggestive of Crohn's disease in patients with inflammatory bowel disease.