Gangrenous Meckel's diverticulum secondary to ascariasis in a child.

Meckel's diverticulum is the most common congenital anomaly of the gastrointestinal tract, which is usually asymptomatic. In patients with intestinal ascariasis, Meckel's diverticulum may pursue a silent course or may be complicated by diverticulitis, gangrene and perforation. We report an unusual complication of volvulus of Meckel's diverticulum and an adjacent segment of ileum due to incarceration of worm bolus in a narrow based Meckel's diverticulum leading to gangrene and perforation.

INTRODUCTION

Ascaris lumbricoides infestation of the intestine is a very common problem faced in developing countries. Though usually asymptomatic, ascariasis-related intestinal complications can be seen in children with a high worm load. Meckel's diverticulum with intestinal ascariasis may remain asymptomatic or present with complications. Ascariasis can directly complicate a Meckel's diverticulum or could be complicated secondarily due to involvement of the segment of ileum on which it is located. The risk of complications increase when associated with a narrow based Meckel's and a high burden of intestinal roundworms. Surgical complications associated with A. lumbricoides infestation include diverticulitis, gangrene or perforation of the Meckel's diverticulum.

CASE REPORT

A two-year-old boy presented to us with a history of excessive cry, bilious vomiting and abdominal distension since three days with worms in the vomitus. On examination the child was pale, toxic, dehydrated and febrile (101°F). Abdomen was distended, tender with generalized rebound tenderness. On investigation he was anemic (hemoglobin of 5.9 gm/dl), with leucocytosis (18.5 × 109/L). Plain X-ray abdomen revealed multiple air fluid levels with no free gas under the diaphragm. Ultrasonography of the abdomen showed dilated small bowel loops with multiple worms and free fluid having internal echoes. Child was resuscitated with intravenous fluids and blood transfusion done. Exploratory laparotomy revealed about 500 ml of purulent fluid with round worms in the peritoneal cavity in the right iliac fossa [Figure 1]. There was a volvulus with gangrene and perforation of Meckel's diverticulum and adjacent 10 cm of the ileum [Figure 2] with worm bolus incarcerated in the Meckel's. The base of the Meckel's was narrow [Figure 3]. In addition, worms were present in whole of the small bowel. Gangrenous Meckel's diverticulum and ileum was resected, worms removed and primary anastomosis done. Peritoneal lavage was given and drain kept. Abdomen was closed in layers. Child had an uneventful post operative period and was discharged on seventh day.

Figure 1

Showing round worm in the peritoneal cavity

Figure 2

Showing volvulus with gangrene and perforation of Meckel's diverticulum and adjacent ileum

Figure 3

Showing narrow-based gangrenous Meckel's diverticulum attached to the ileum

DISCUSSION

Meckel's diverticulum is the most frequent congenital anomaly of the gastrointestinal (GI) tract, occurring in 2% of the population.[1] It is located on the antimesenteric border of the ileum and in 90% of the cases within 90 cm from the ileo-cecal valve, although it has been reported up to 180 cm. Most cases remain asymptomatic throughout life. Symptoms develop in 4.2%–6.4% cases,[23] about half of whom are in age group of less than two years. Hemorrhage is the most common presentation, which occurs in 25%–50% of patients who present with a complication.[45] Intestinal obstruction follows bleeding as the next most common complication, occurring in 25% of the symptomatic patients. It usually results from either an intussusception or a volvulus around mesodiverticular band. This is followed by diverticulitis in 20% of symptomatic cases. A long Meckel's diverticulum with a narrow base predisposes to intraluminal obstruction causing inflammation, necrosis, and perforation akin to acute appendicitis. In addition, an isolated perforation of a Meckel's peptic ulcer may also occur.[4] Meckel's diverticulum rarely undergoes torsion from axial twisting of the diverticulum around its narrow base resulting in vascular compromise and gangrene.[2]

A variety of abdominal complications of A. lumbricoides occur in children due to their wandering nature. Intestinal obstruction, gangrene and perforation are the common complications of ascariasis, intestinal obstruction being the commonest.[6] Intestinal obstruction can be due to a worm bolus, intussusception or volvulus of the small gut. Association of A. lumbricoides with Meckel's diverticulum in children rarely leads to its complications. Heavy worm infestation may lead to Meckel's diverticulitis secondary to worm incarceration.[7] Incarceration is usually caused by interlocking of multiple small sized roundworms in a long narrow based diverticulum. Worm bolus induced obstruction can occasionally lead to the gangrene and perforation of ileum and Meckel's diverticulum secondary to pressure necrosis leading to peritonitis.[8] Bowel necrosis and perforation are a consequence of vascular compromise due to the pressure of impacted worms.[910] Gangrene of Meckel's diverticulum may also occur following volvulus of adjacent ileal segment due to incarcerated worm bolus as happened in our case. Here we report this unusual complication of Ascaris infestation in a Meckel's diverticulum.