Diversion colitis in children: an iatrogenic appendix vermiformis?

Area of Science:

• Pediatric Gastroenterology
• Colorectal Surgery
• Surgical Pathology

Background:

• Diversion colitis (DC) is a common iatrogenic condition in diverted colonic segments after ileostomy or colostomy.
• Understanding its histological features in children is crucial for accurate diagnosis and management.

Purpose of the Study:

• To establish and describe the characteristic histological features of diversion colitis in pediatric patients.
• To differentiate DC from other colonic pathologies in children, such as ulcerative colitis and Hirschsprung's-associated enterocolitis.

Main Methods:

• Analysis of 23 pediatric cases of diversion colitis following colostomy for Hirschsprung's disease.
• Detailed examination of histological findings, including mucosal inflammation, lymphoid hyperplasia, and metaplasia.

Main Results:

• Consistent findings in pediatric DC include prominent follicular lymphoid hyperplasia (100%) and chronic mucosal inflammation (100%).
• Variable acute inflammation (78%), Paneth cell metaplasia (26%), and eosinophil aggregates (43%) were also observed.
• Histological features showed significant similarity to those in adults and the normal appendix.

Conclusions:

• Pediatric diversion colitis exhibits histological characteristics similar to adult DC, aiding in distinguishing it from ulcerative colitis and Hirschsprung's-associated enterocolitis.
• Recognition of these features is vital to prevent misdiagnosis and inappropriate treatment in children.
• The study highlights similarities between diversion colitis and the normal appendix vermiformis.