Focal active colitis: Diagnostic relevance and long-term clinical outcomes

Area of Science:

• Gastroenterology
• Histopathology
• Clinical Outcomes

Background:

• Focal active colitis (FAC) is a histopathologic finding of focal neutrophilic crypt injury.
• The clinical significance of FAC, especially its link to inflammatory bowel disease (IBD), requires further investigation.

Purpose of the Study:

• To evaluate the clinical implications and long-term outcomes of patients diagnosed with focal active colitis (FAC).
• To determine the association between FAC and the development of inflammatory bowel disease (IBD) and other gastrointestinal conditions.

Main Methods:

• Retrospective review of colorectal biopsies diagnosed with FAC from 2005-2024.
• Analysis of clinical outcomes, endoscopic findings, and subsequent diagnoses in adult patients with isolated FAC and follow-up data.

Main Results:

• Out of 419 patients, only 2.15% developed IBD (Crohn's disease, ulcerative colitis, or unclassified).
• Common associations included Irritable Bowel Syndrome (IBS) (33.2%), infectious colitis (11.2%), and drug-induced colitis (8.6%).
• No specific histologic features predicted progression to IBD.

Conclusions:

• Focal active colitis (FAC) is frequently associated with non-IBD conditions like IBS, infections, or drug reactions.
• The progression of FAC to IBD is uncommon (2.15%), and no histological predictors were identified.
• FAC is a nonspecific finding; symptomatic patients require follow-up, while incidental cases are typically clinically insignificant.