An extremely rare complication of Meckel's diverticulum: enterocutaneous fistulization of umbilical hernia.

INTRODUCTION

Meckel's diverticulum is the most common malformation of the gastrointestinal tract with an incidence of 2% of the population. This congenital anomaly results from incomplete yolk duct development[1]. Meckel's diverticulum has a complication rate of 4-6%. Most common complications are haemorrhage, perforation, obstruction and inflammation[4]. It is mostly asymptomatic and most often diagnosed when complications occur. Also it may be diagnosed incidentally during laparoscopy or laparatomy for unrelated conditions[1].

Fistula formation (between abdominal organs), herniation (of abdominal wall), and Littre hernia (protrusion of a Meckel's diverticulum through an abdominal wall defect) are well-described complication. However, umbilical herniation of Meckel's diverticulum is rare[3]. Herein is presented a case with enterocutaneous fistula between Meckel's diverticulum and umbilicus associated with umbilical hernia.

CASE REPORT

A 40-year-old man was admitted to the department of General Surgery with a 24 h history of abdominal pain focused on the umbilical region, as well as fever, anorexia and vomiting. He had a history of previous umbilical abscess drainage five years ago. He reported no other medical history. Examination of the abdomen showed tenderness over the umbilical region without abdominal guarding and rigidity. A leakage of intestinal fluid through an opening (an external fistula orifice) was determined inside the umbilicus. There was no increase in local heat, swelling or edema. The laboratory findings, including complete blood count and electrolytes, and abdominal X-ray showed no abnormality. Abdominal ultrasound showed a well-limited liquid collection of 1.5x1.5 cm subcutaneously under the umbilicus. The contrast-enhanced abdominal computerized tomography scan revealed a small intestine segment lying subcutaneously throughout the fascia defect on the umbilicus The intestine was fistulized throughout the umbilical hernia into the external layer of the skin (Figure 1). With the clinical and radiological findings, the patient was initially diagnosed as enterocutaneous fistula with a Meckel's diverticulum. In the surgery, abdomen was opened and the exploration revealed Meckel's diverticulum (lying subcutaneously throughout the fascia defect on the umbilicus) and a fistula between this and the umbilicus. There was no fluid contamination in the abdomen. A diverticulectomy and an excision including the fistula tract and umbilicus were performed (Figure 2). The patient was discharged at fifth postoperative day safely. Histopathologic examination approved Meckel's diverticulum.

Figure 1.

Contrast enhanced CT shows an intestine fistulized throughout the umbilical hernia into the external layer of the umbilical skin

Figure 2.

Intraoperative image showing the Meckel's diverticulum forming enterocutaneous fistulization of Littre's umbilical hernia

DISCUSSION

Various complications of Meckel's diverticulum include ulcerations, gastrointestinal bleeding, intestinal obstructions due to bands, intussusceptions, diverticulitis, perforations and neoplasms[2, 3]. In patients under 18, the most common presentation is haemorrhage, while in adults it is intestinal obstruction. Beyond all, development of fistula is a rare complication. In literature, enterocolonic fistula, vesicodiverticular fistula and ileorectal fistula have been reported as case reports and recently a fistula between Meckel's diverticulum and the appendix has been published[5]. However, the search of Pubmed literature failed to find any previous study regarding a fistula between a Meckel's diverticulum and the umbilicus.

A possible explanation for this situation is that Meckel's diverticulum may congenitally be localized in the umbilical hernia sac. An inflammatory attack of Meckel's diverticulum in the hernia sac leads to an abscess formation and sinus. When missed, or undiagnosed, an enterocutaneous fistula may occur. Based on the experience in this case, complications of Meckel's diverticulum should be considered during differantial diagnosis of enterocutaneous fistula.