Analysis of fluid in craniopharyngioma-related cysts in children: proteins, lactate and pH.

The purpose of this study was to evaluate the possible role of blood-brain barrier disruption in cyst formation in craniopharyngioma. Fifteen samples of cyst fluid and 14 samples of blood serum were collected from 14 patients with cystic forms of craniopharyngiomas and studied biochemically regarding total protein, albumin, immunoglobulins G and M contents, lactate and pH. Analysis of the data obtained for cyst fluids according to Felgenhauer and comparing them to those obtained for the corresponding blood sera led us to prove the hypothesis of blood-brain barrier impairment in patients with cyst formations in craniopharyngioma. We have also revealed an elevated lactate content and decreased pH in cyst fluids compared with blood sera. Thus the pathogenesis of craniopharyngiomal cyst appears to be much more akin to those described for cysts accompanying other brain tumours than it was believed earlier.