Is focal active colitis of greater clinical significance in pediatric patients? A retrospective review of 68 cases with clinical correlation.

Focal active colitis (FAC) is a histopathologic finding of uncertain clinical significance in individual patients. In adults, infection accounts for approximately 50%, Crohn's disease (CD) for 0-13%, and 20%-30% are idiopathic. One previous study of 29 cases of pediatric FAC showed a 28% rate of CD. This study reviewed a larger cohort of pediatric patients to determine what proportion had IBD, and whether an amount or pattern of inflammation could predict IBD. Sixty-eight patients aged ≤18years with FAC were identified and reviewed. Patients with a prior diagnosis of IBD or chronic colitis in the index biopsies were excluded. Slides were assessed for a number of inflammatory criteria. Clinical data and final diagnoses were recorded. Data were analyzed using Pearson correlations and Fisher's exact χ2 analyses. Sixteen patients (24%) had a final diagnosis of IBD. When cases with terminal ileal (TI) inflammation were excluded, 6 of 54 patients had a final diagnosis of IBD (11%). A final diagnosis of IBD was significantly associated with crypt abscesses and elevated serum inflammatory markers. IBD was significantly associated with TI inflammation. An amount or pattern of inflammation that could be used to predict IBD was not determined. This study demonstrated a 24% rate of IBD in pediatric patients with FAC; however, when patients with associated TI inflammation were excluded, the rate was 11%, similar to reported rates in adults. FAC in pediatric patients without terminal ileal inflammation does not appear to warrant more aggressive follow-up.