Peroral extrusion of the peritoneal catheter in an infant.

Peroral extrusion of the distal end of a ventriculo-peritoneal shunt tube is the potentially hazardous end result of a bowel perforation with only few case reports in the literature. The distal end of the peritoneal catheter got fractured in a 4-year-old child and it protruded out through the mouth. The cranial incision was opened and the shunt divided below the chamber. The ventricular end and the chamber and distal end were removed through this incision. In the present successfully managed case we review the current strategies in the management of such a rare complication and discuss the possible pathogenesis of this entity.

Introduction

Ventriculoperitoneal (VP) shunt surgery is one of the most commonly used techniques for the treatment of hydrocephalus and can be associated with a number of complications and if not recognized in a timely manner these complications can be fatal.[1-3] One such rare complication is peroral extrusion of the distal end of a ventriculo-peritoneal that can be the end result of a bowel perforation by shunt catheter.[13-10]

In present successfully managed case, we review the current strategies in the management of such a rare complication and discuss the possible pathogenesis of this rare complication.

Case Report

A 4-year male child presented with the history of one episode of vomiting and following which the parents noticed that there was a tube protruding through the mouth. The distal end of the peritoneal catheter got fractured and parents brought the same with them. The child was operated for congenital hydrocephalus at the age of 6 months and a right ventriculo-peritoneal shunt was placed. He was asymptomatic since that time with normal development. There was no history of features of meningitis or intestinal obstruction including pain abdomen. There was no history of fever, excessive crying, or any significant problem preceding this event.

On admission to the hospital, the patient was conscious, had spontaneous eye opening, and had no neurological deficits. The shunt tract was normal with no signs of inflammation. The abdomen was soft and bowel sounds were normal. Plain radiography showed no displacement of the cranial end of the shunt tube; however the peritoneal end was seen traversing posteriorly to the stomach on the left side and entering into the stomach in a retrograde manner [Figures 1 and 2].

Figure 1

Plain X-ray film showing the peritoneal end of the shunt along with the nasogastric tube in the stomach (in inset please note the bile staining of the peritoneal catheter)

Figure 2(a-f)

CT scan showing the trajectory of the peritoneal end as seen that it is traversing posterior to the stomach on the left side and entering into the stomach in a retrograde manner, perforating probably the stomach

It was decided to remove the shunt and decide regarding the need for replacement depending upon the presence or absence of infection. The cranial incision was opened and the shunt divided below the chamber. The ventricular end and the chamber and distal end were removed through this incision. The child was maintained on intravenous fluids and antibiotics for 36 hours. The child was then started on oral feeds, which he tolerated well. He was given cephalosporin antibiotics.

The child was discharged after 2 weeks, at which time he was totally asymptomatic. At 12-month follow-up the child remained asymptomatic.

Discussion

Spontaneous bowel perforation is a rare complication of a VP Shunt, seen in only 0.01-0.07% of cases,[511] Extrusion most commonly occurs through the anal orifice (61.9%)[9] and peroral extrusion is extremely rare.[13-10] Usually these patients present with features of ventriculitis or meningitis due to an enteric organism, as in the present case patients with proximal perforations involving stomach or proximal jejunum are less prone to severe infectious complications than are perforations of the distal intestine like the colon.[4] It has not been clear why the shunt tube should extrude through the mouth although it has been proposed that shunt tract infection can probably lead to inflammation and adherence of the tube to the proximal gut and subsequent perforation.[4]

In the present case probably the peritoneal end was traversed behind the stomach and trapped at some point and was continued to be pushed behind by the intraabdominal pressure creating a vicious cycle resulting in the perforation of stomach as was supported by the trajectory of the tubing on imaging findings. As in the present case once perforated and lying in the stomach or the jejunum, the tube may be made to travel into the oral cavity by forceful repeated vomiting and retching,[4] bowel perforation and shunt tube extrusion do not always have a benign course and can be associated with very high mortality.[13410]

Due to rarity of such complication, the correct management is not certain; however peroral extrusion of the shunt tube needs prompt treatment. The first step should be to look for any infection and for shunt tract inflammation, followed by removal of extruded shunt tube and the ventricular end through a clean cranial incision, and attention to bowel perforation.[4] Most of the time in these patients a major laparotomy is not necessary as the opening in the bowel is small and can seal off spontaneously.[410]

Although majority of the patients will need replacement of the shunt device; however, as in the present case, a few may not require the replacement of shunt due to spontaneous opening up of CSF pathways which were not yet mature when the initial shunt was placed, making the patient shunt independent.[4]