Background: Symptomatic, sterile cerebrospinal fluid (CSF) ascites is a rare complication of ventriculoperitoneal (VP) shunt surgery. To date, reports in the literature have linked this unusual circumstance to various intra-abdominal, CNS, or nonspecific inflammatory causes.
Case report: We present the case of a four-year-old boy with a recently fenestrated arachnoid cyst and VP shunt, who presented with sudden-onset, sterile CSF ascites. The ascites resolved with conversion of the preexisting VP shunt to a ventriculoatrial shunt.