Pouch colon associated with anorectal malformations fails to show spontaneous contractions but responds to acetylcholine and histamine in vitro.

PURPOSE: Congenital pouch colon (CPC) associated with anorectal malformation (ARM) is most commonly reported from Northern India. So far, no physiologic study comparing the detailed contractile status of CPC with non-CPC conditions are available. The present article deals with the contractile study and histopathologic observations in CPC, which may be useful for better surgical management. METHODS: Freshly excised 12 neonatal CPC and similar number of non-CPC (control) specimens were transferred to ice-cold (4 degrees C-6 degrees C) Krebs-Ringer solution bubbled with 100% oxygen. Longitudinally prepared 2 to 4 colonic strips were obtained from central part of each specimen and subjected to the contraction recording after exposure to cumulative concentrations of acetylcholine (ACh) and histamine. Acetylcholine-induced contractions were evaluated after application of atropine (muscarinic blocker), and histaminergic contractions were recorded after pheniramine (H(1) blocker), lignocaine (neuronal blocker), and atropine. Histopathologic observations were made by using H&E and Masson trichrome stains. RESULTS: Control specimens showed spontaneous contractions, but CPC strips did not. Both control and CPC responded to ACh and histamine. The response to histamine was greater (P < .05) in CPC as compared to control, whereas the response to ACh was more (P < .05) in control. In CPC, response of histamine (100 micromol/L) was blocked by pheniramine (0.32 mmol/L) and lignocaine (4 mmol/L) by 97% and 80%, respectively, and enhanced by 57% after preapplication of atropine (10 micromol/L). Acetylcholine (100 micromol/L)-induced contractions were attenuated (86%) in presence of atropine. Histopathologic examination showed fewer mature ganglion cells with various changes in muscle layers including fibrosis, disruption, hypertrophy, atrophy, and constriction bands. CONCLUSION: Congenital pouch colon associated with ARM lacks normal spontaneous contractions but retains ACh and histamine-induced contractility. In view of the functional and histologic abnormalities, we propose that CPC associated with ARM is an abnormally functional and developed tissue. Therefore, resection of the pouch should be considered for better functional outcome of the remaining bowel.

Perforated congenital diverticulum of the sigmoid colon.

A case of perforation of a congenital sigmoid diverticulum producing diffuse peritonitis in a 4-year-old boy is presented. Physical examination showed an acute abdomen despite a normal computed tomography study. Successful surgical treatment was achieved by excision of the diverticulum, adjacent bowel, and an end-to-end anastomosis.

Uroepithelium in a colonic diverticulum.

Giant colonic diverticula are rare entities and often present in adulthood as acute diverticulitis. The authors present a case of giant colonic pseudodiverticulum lined with uroepithelium causing bowel obstruction in a neonate. The presence of uroepithelium in a colonic pseudodiverticuium remains unexplained and to the authors' knowledge unreported. This heterotopic tissue may be a result of an embryonic rest or could be urachal in origin adhering initially to the colon and eventually detaching from the umbilicus. These lesions should be resected because of the risk of infection, perforation, or obstruction.

Congenital small bowel diverticulosis and intestinal atresia: a rare association.

An unusual case of multiple intestinal atresias with multiple small bowel diverticulae is presented. To the best of our knowledge this is the first reported case of its kind in the literature.