Spontaneous Umbilical CSF Fistula Due to Migration of the Peritoneal End of VP Shunt: A Case Report and Review of Pathogenesis.

Abdominal complications after ventriculoperitoneal (VP) shunt surgery for hydrocephalus have been known to occur. The more common complications include peritoneal pseudocyst, obstruction of the lower end, and shunt infection. Perforations of the intra-abdominal hollow viscera leading to spontaneous extrusions of the peritoneal catheter via the natural orifices have also been reported. A rarer phenomenon still is the migration of the lower end of the VP shunt through the anterior abdominal wall, leading to the formation of a spontaneous umbilical fistula at a site unrelated to the surgical site. Eight cases have been described in the literature so far with various causes elucidated. We report this condition in a child 4.5 years after his shunt surgery and postulate different mechanisms for both early and late presentations of this condition.