A Histopathological Study of Congenital Pouch Colon and its Impact on Management

Background: Congenital Pouch colon(CPC) is a rare variant of anorectal malformations (ARM) whose etiopathogenesis and management are not yet standardized. This prospective study seeks to establish the histopathological characteristics and it’s inference on the etiopathogenesis, management and prognosis of CPC. Methods: This was a prospective comparative study including all neonates with CPC and other high ARM. The excised pouch from the neonates with CPC and a strip of sigmoid colon from other high ARM patients were sent for biopsy and the histopathological features compared. Results: Histopathogical abnormalities were seen involving all the layers of the colonic pouch including mucosa, submucosa and muscularis propria. The statistically significant histopathological differences in the colonic pouch as compared to normal sigmoid colon were mucosal necrosis, focal erosions, inflammation and haemorrhage, muscularis mucosa fibrosis, submucosal congestion and haemorrhage, widening, fibrosis and presence of lymphoid follicles and circular and longitudinal muscle disarray and fibrosis. Also seen was a significant inflammatory infiltrate permeating all the layers of the pouch. Conclusion: CPC has histopathological abnormalities in all the layers of the colon. It is thus pathologically abnormal tissue. The widespread inflammatory reaction in all layers of the CPC raises the possibility of some environmental factor having a role in etiopathogenesis of CPC.