Acquired intestinal atresia in young girl: Extremely rare case

Background: A postnatally acquired ileal atresia is very rare. Only few cases are described in literature and the etiology is still unclear. Case Description: A Girl 15 years old was referred to Zainoel Abidin hospital with abdominal distention and can’t pass motion for 10 days ago. She also had intermittent colicky pain and billious vomiting. Previously, she had surgical correction for anorectal malformation with rectovestibular fistulae. Physical examination revealed tachycardia and tachypnea with abdominal distention as well as metallic sound even though there was no sign of peritonitis. Anal position index was normal and rectal vault collapse. Potassium level was low. Abdominal x-ray revealed multiple air-fluid level and gas only in the ileum level with dilatation all small bowel. Exploratory laparotomy was prompted and there was acquired atresia (type II) in the ileum 70 cm from ileocaecal valve due to adhesive band that twisted the bowel to the umbilical area. Proximal tappering and anastomosis end to end ileoileal were performed. She was discharged on operative day 7 with uneventful recovery. Conclusion: Intestinal atresia typically presents in neonatal period with the classical symptoms of abdominal distension and vomiting.


INTRODUCTION
Intestinal atresia is a congenital obstruction of the intestine, sometimes associated with a loss of tissue, resulting in a disruption of intestinal continuity. An atresia can occur anywhere throughout the gut, including the oesophagus, pylorus, pancreatic duct, bile duct and rectum. The incidence of intestinal atresia is approximately 1 in 4000 live births. In 1955 a landmark. study conducted by Louw and Barnard documented that intrauterine mesenteric vascular accidents were responsible for most jejunoileal atresias. 1,2 Acquired or postnatal atresia could arise from a similar aetiology like congenital small bowel atresia but still debate and unclear. 3 This article describes a case of acquired ileal atresia in a 15 years-old female who had an adhesive small bowel obstruction.

CASE REPORT
A Girl 15 years old was referred to Zainoel Abidin Hospital with abdominal distention and can't pass motion for 10 days ago. She also had intermittent colicky pain and billious vomiting. Previously, she had surgical correction for anorectal malformation with rectovestibular fistulae.
Physical examination revealed tachycardia and tachypnea with abdominal distention as well as metallic sound even though there was no sign of peritonitis. Anal position index was normal and rectal vault collapse. Potassium level was low (2,6 Meq/L) and already corrected. Abdominal x-ray revealed multiple air-fluid level and gas only in the ileum level with dilatation all small bowel.
Exploratory laparotomy was prompted and there was acquired atresia (type II) in the ileum 70 cm from ileocaecal valve due to adhesive band that twisted the bowel to the umbilical area ( Figure 2A). The adhesive band was released and proximal tappering and anastomosis end to end ileoileal handsewn was performed. She was discharged on operative day 7 with uneventful recovery.

DISCUSSION
Acquired intestinal atresia was first described by Michaelis in 1971 in a 19 months old boy in whom ileal atresia developed after drainage of a large intraabdominal abscess of undetermined etiology. 4,5 Theories on the pathogenesis of intestinal atresia have been reviewed and concluded that postnatal progression to stenosis and atresia is caused by trauma to the intestine presumably from distension and ischemia. The most common type of congenital atresia was type II, but in acquired atresia is type III A. 5, 6 Acquired atresia of the bowel is known common occur in premature infants after recovery from necrotizing enterocolitis (NEC). Acquired intestinal atresia in non necrotizing enterocolitis affected patients is very rare. 7 We could find only eight case Pediatric Surgery Division, Department of Surgery, Faculty of Medicine, Syiah Kuala University/ Dr. Zainoel Abidin Hospital, Banda Aceh, Aceh, Indonesia reports of acquired atresia of the small bowel in non-NEC patients in literature, but our patient is the older than others. 3- 10 All author report acquired atresia occur in the ileum because of adhesive small bowel obstruction and intussusception. 3-10 In their opinion, chronic entrapment of the ileal segment together with its mesentery by an adhesive band interrupting the blood supply resulted in acquired ileal atresia. 5, 6 Ratan et al. Reported that acquired intestinal atresia is a rare but possible sequela of gut inflammation and/or intussusceptions. 10 In our case, the atresia occurs in mid ileum due to adhesive small bowel obstruction. We think the obstruction already occurs not only for 10 days, but longer before the total obstruction occur. The atresia may be because chronic twisting of the mid ileum segment together with its mesentery by an adhesive band interrupting the blood supply. Ischemia and ongoing inflammation with further resorption of the devitalised segment were likely involved resulting in complete healing of the atretic ends.

CONCLUSION
Intestinal atresia typically present in neonatal period with the classical symptoms of abdominal distension and vomiting. Available reports imply that mechanical forces on the intestine (adhesive band, volvulus, and intussusception) dominate the pathogenesis of acquired intestinal atresia.