Granulomas in Crohn's disease: does progression through the bowel layers affect presentation or predict recurrence?

Aim The aim of the study was to correlate the presence and pattern of distribution of granulomas in resected specimens to clinical characteristics and outcome in patients undergoing surgery for Crohn's disease. Method Patients with Crohn's disease who underwent surgical resection between 2001 and 2007 were identified. Pathology slides were reviewed for the presence, number and location of granulomas in four representative slides from each specimen. Results Two-hundred and seven patients were identified. At a mean follow up of 14 months, 39 patients had a recurrence, 22 (57%) of whom underwent reoperation. Ninety-four (45%) patients had granulomas present in the surgical specimen. Patients with granulomas were younger (P < 0.001), had a lower preoperative body mass index (P = 0.037), were more likely to be female (P = 0.017) and were more likely to have extra-intestinal manifestations (P = 0.026) or perianal disease (P = 0.012). Sites of disease and procedures performed were similar in both groups. Disease recurrence and reoperative rates were similar in both groups, as were length of stay and morbidity rates. The average number of granulomas present in each sampled pathology slide was 7.2, and there was no correlation between number of granulomas and disease severity. No link was found between the depth of involvement of the granulomas and fistulizing or stricturing disease. Conclusion Granulomas were associated with increased extra-intestinal manifestations and perianal disease, a lower body mass index and younger or female patients. There was no correlation between the presence of granulomas and disease progression or recurrence rates during the short follow-up period of this study.