Focal active colitis: a prospective study of clinicopathological correlations in 90 patients

Considerable controversy exists about the clinical implication of a diagnosis of focal active colitis (FAC). The aim of this study was to assess clinicopathological correlations of FAC in 90 adults, representing the largest and only prospective series of FAC.

Patients were assessed by comprehensive clinical follow-up and questionnaires. Fifteen histopathological features were scored and correlated with clinical outcome. In 24% of patients drugs, especially NSAIDs, were implicated. Infection was a probable cause in 19%. In 14 patients (15.6%), predominantly women, a diagnosis of chronic inflammatory bowel disease was ultimately made. Most were Crohn's disease, but this is the first study in which FAC has presaged an ultimate diagnosis of ulcerative colitis in adults (in two patients). A specific subtype of FAC, termed basal FAC, was significantly associated with drugs. These excepted, this study has found no histopathological parameters of FAC, such as amount, location and/or distribution, to correlate with clinical outcome or allowed selection of those patients more likely to show subsequent evidence of chronic inflammatory bowel disease.

This study has provided powerful information on the implication of a diagnosis of FAC. In a small but not inconsiderable case number, the ultimate diagnosis will be chronic inflammatory bowel disease.