Frequency and clinical correlations of granulomas in children with Crohn disease.

BACKGROUND: Granulomas are pathognomonic findings of Crohn disease (CD); however, their occurrence and clinical significance are not well characterized. Our aim was to determine the frequency and distribution of granulomas in untreated and treated patients with CD and their relation to age and disease severity.

PATIENTS AND METHODS: Records from patients with CD undergoing colonoscopy with terminal ileum biopsy over 7 years were reviewed. Clinical information and laboratory, pathology, and radiology results were recorded. The frequency and distribution of granulomas were determined.

RESULTS: From 376 patients with CD, 75% underwent concurrent esophagogastroduodenoscopy and colonoscopy. Of those, 65% (184/282) were untreated. Granulomas were identified in 48% (136/282) of all patients and in 61% (112/184) of untreated patients and 24.5% (24/98) of treated patients (P < 0.0005). The upper tract and terminal ileum biopsies were essential to the identification of 42% of patients with granulomas. The presence of granulomas at diagnosis was related to anti-Saccharomyces cerevisiae antibodies, hypoalbuminemia, perianal disease, and gastritis at presentation (P = 0.03, P = 0.008, P = 0.03, and P = 0.001), respectively, and to perianal disease and infliximab treatment at the latest visit (P = 0.02 and P = 0.01), respectively. Granulomas were not related to age, sex, ethnicity, weight and height z scores, hemoglobin, C-reactive protein, erythrocyte sedimentation rate, CARD15/NOD2 mutations, abdominal surgery, or stricturing or fistulizing disease.

CONCLUSIONS: Granulomas were identified in 61% of fully investigated pediatric patients with CD at diagnosis, including a substantial proportion of patients in whom colonoscopy to the cecum would have been insufficient for diagnosis. Granulomas were more frequent in untreated patients (P < 0.0005), and their prevalence was not affected by age. The presence of granulomas at diagnosis was associated with perianal disease, gastritis, hypoalbuminemia, anti-Saccharomyces cerevisiae antibodies, and infliximab treatment.