Congenital aganglionic megacolon in Nigerian adults: two case reports and review of the literature.

Congenital aganglionic mega colon (Hirschsprung's disease) is a motor disorder in the gut, due to a defect in the craniocaudal migration of the neuroblast originating from the neural crest that occurs during the first twelve weeks of gestation, causing a functional intestinal obstruction, with its attendant complications, in infants. Despite modern pediatric practice, with emphasis on early diagnosis, Hirschsprung's disease is seen in adults in regions where perinatal care is limited. We report two cases of Nigerian adults with longstanding, recurrent constipation, getting relieved by laxatives and herbal enemata, and then presented to our Emergency Department with a history of progressive abdominal distention, colicky pain, occasional vomiting, and weight loss. Per rectal examination revealed a gripping sensation in the rectum, 10 cm from the anal verge, with rectal fecal load. Barium enema showed a grossly distended proximal large colon, with high fecal retention, with the transition zone at the middle one-third of the rectum. Due to difficulty in bowel preparation of these patients, emergency laparotomy was done. The first case had a diverting sigmoid colostomy and later had a low anterior resection. The second case had a one-stage procedure. Histology of both the cases showed aganglionosis of the stenotic segment and a normal distal rectum. Both patients had complete resolution of the symptoms, without complications, in a three-year follow-up. The related literatures were reviewed. Hirschsprung's disease should be considered in adults patient presenting with chronic constipation. Low anterior resection of the rectum would be a surgical option for the treatment of short and zonal segment of adult Hirschsprung's disease.