Comparison of cerebrospinal fluid biomarkers between idiopathic normal pressure hydrocephalus and subarachnoid hemorrhage-induced chronic hydrocephalus: A pilot study

Abstract

Background: We examined the cerebrospinal fluid (CSF) markers of subarachnoid hemorrhage (SAH)-induced and idiopathic normal pressure hydrocephalus (INPH) to investigate the pathophysiology and mechanism of communicating hydrocephalus compared to obstructive hydrocephalus. Material/Methods: We obtained CSF samples from 8 INPH, 10 SAH-induced hydrocephalus, and 6 unmatched patients with non-hemorrhagic obstructive hydrocephalus during their ventriculoperitoneal shunt operations. Transforming growth factor (TGF)-beta 1, tumor necrosis factor (TNF)-alpha, vascular endothelial growth factor (VEGF), and total tau in the CSF were analyzed via enzyme-linked immunosorbent assay. Results: The mean VEGF levels in the CSF of patients with SAH-induced hydrocephalus, INPH, and obstructive hydrocephalus were 239 +/- 131, 239 +/- 75, and 163 +/- 122 pg/mL, respectively. The total tau concentrations in the CSF of the groups were 1139 +/- 1900, 325 +/- 325, and 1550 +/- 2886 pg/mL, respectively. TNF-alpha values were 114 +/- 34, 134 +/- 38, and 55 +/- 16 pg/mL, respectively. TGF-beta 1 values were 953 +/- 430, 869 +/- 447, and 136 +/- 63 pg/mL, respectively. A significant difference in TNF-alpha and TGF-beta 1 levels was observed only between SAH-induced and chronic obstructive hydrocephalus, and between INPH and chronic obstructive hydrocephalus (p<0.01). Conclusions: No significant differences in the 4 CSF biomarker levels were observed between INPH and SAH-induced hydrocephalus, whereas CSF TNF-alpha and TGF-beta 1 levels were increased compared to those in patients with chronic obstructive hydrocephalus. Post-SAH hydrocephalus and INPH are probably more destructive to neural tissues, and then stimulate the inflammatory reaction and healing process, compared with obstructive hydrocephalus.