The treatment for hydrocephalus is either by a V-P or a V-A shunt procedure. V-A shunting is used infrequently because of life-threatening complications like venous thrombosis, bacteraemia and sepsis; hence, the V-P shunt is preferred. Occlusion of the shunt tube and infection are frequently observed complications of V-P shunt.1
Other rare complications include intracranial haematoma, intestinal perforation by the tube,2
and tube migration to the thorax and scrotum.3
CSF ascites is a very rare complication of V-P shunt. To the best of our knowledge, only 28 cases of shunt ascites have been reported in the world literature4
and, out of these, 4 cases had craniopharyngioma. Several aetiological factors have been discussed in literature, but all are elusive. An imbalance between peritoneal absorptive capacity and amount of CSF production is implicated as a major cause of shunt ascites. Therefore, patients with excessive amounts of CSF production like choroid plexus papilloma are at the risk of developing CSF ascites following V-P shunt.5
Similarly, patients with high CSF protein due to chronic infection (tuberculous meningitis)6
or brain tumours, especially optic glioma,7
may have difficulties in CSF absorption through the peritoneum due to high viscosity. Peritoneal inflammation due to repeated shunt revisions,8
or non-specific inflammatory response to shunt material,9
may also play a role in decreasing the absorptive ability of the peritoneum. Recently, vascular permeability factor secreted by both low and high grade gliomas are implicated in the formation of shunt ascites.10
However, in most reported cases, the aetiology was unknown and V-A shunt was effective. Out of the four cases of shunt ascites reported in patients with craniopharyngioma, only two had resolution of ascites following V-A shunting.4
Our patient had shunt ascites 1 year following V-P shunt. Non-specific peritoneal inflammation to shunt material or some putative inflammatory factor released from craniopharyngioma might be the cause for his ascites, which successfully resolved after V-A shunt.
- Shunt ascites is a rare complication following V-P shunt procedure.
- The diagnosis requires a high index of suspicion.
- Removal of the V-P shunt and placement of a V-A shunt is curative.