Internal hernia as a cause of bowel strangulation in pediatric age group.

Sir,

Internal hernia in pediatric age group is a relatively rare but known entity. It can be asymptomatic, cause chronic abdominal pain, or present with acute intestinal obstruction with strangulation and ischemia. We have encountered three cases of internal hernia (transmesenteric, paravesical and paraduodenal) with bowel strangulation in pediatric age group, the diagnosis of which was uncertain in the preoperative period but was evident on table requiring a resection and end to end anastomosis. The purpose of our report is not only to emphasize the importance of the particular condition in pediatric age group but also to consider it as one of the differential diagnoses in a patient being evaluated for intestinal obstruction.

The cases we encountered presented with complaints of abdominal distention, constipation, bilious vomiting, and abdominal pain. Abdomen was grossly distended and tender with absent bowel sounds. X-ray abdomen revealed dilated small bowel loops with multiple air fluid levels. A provisional diagnosis of sub acute small bowel obstruction with peritonitis was made and the patients were posted for exploratory laparotomy. On exploration, dilated small bowel with a loop entangled in a large defect in ileojejunal mesentery [Figure 1] of approximately 6 × 8 cm in size in first case, bowel loop approximately 2 feet distal to D-J junction herniated and strangulated into paraduodenal fossa in the second and strangulated small bowel secondary to herniation into paravesical space was seen in the third case. A resection with end to end anastomosis of bowel was done; patients recovered well in the postoperative period and were subsequently discharged.

Figure 1

Defect in ileojejunal mesentery

Congenital internal hernia (CIH) is classified according to its location in decreasing order of frequency as paraduodenal, transmesenteric, intersigmoid and paravesical hernia. In congenital transmesenteric hernia (TMH), the hernial defect is most often situated in the small bowel mesentery, around 10-15 cm proximal to the ICJ. The defect is usually small, approximately 2 × 3 cm in size. TMH has been reported mainly in children between 3 and 10 years of age.[1] Paraduodenal hernia, the most common cause of internal hernia, may be due to an unusual paraduodenal sac formed by a peritoneal membrane between the transverse and the descending colon.[2] There are 2 types of paraduodenal hernias: Left-sided and right-sided. The left-sided hernia involves the paraduodenal fossa of Landzert while the right-sided ones involve fossa of Waldeyer. Paravesical hernias are probably the rarest of all internal hernia. The supravesical fossa is the abdominal wall area between the remnants of the urachus (median umbilical ligament) and the left or right umbilical artery (medial umbilical ligament).[34] The remnant of the urachus divides into the right and left fossa. There are two variants of supravesical hernias: An external form caused by the laxity of the vesical pre-peritoneal tissue, and an internal one with a growing hernia sac from back to front and above the bladder in a sagittal paramedian direction.[45]