Cerebrospinal fluid obstruction and malabsorption in human neonatal hydrocephaly.

INTRODUCTION: The pathophysiology involved in human neonatal high-pressure hydrocephalus (HC) includes both cerebrospinal fluid (CSF) malabsorption and obstruction.
OBJECTIVE: The aim was to estimate the relative contribution between CSF malabsorption and obstruction in three different etiological groups of neonatal high-pressure HC by assessment of specific CSF biomarkers indicative of growth factor- and fibrosis-related CSF malabsorption (transforming growth factor beta-1 (TGF beta-1), aminoterminal propeptide of type 1 collagen (PC1NP)].
MATERIALS AND METHODS: Patients were subdivided into three groups. Group A: spina bifida HC (n=12); group B: non-haemorrhagic triventricular HC (n=4); and group C: posthaemorrhagic HC (n=6). To exclude for confounding differences in pro-inflammatory state between the three groups, interleukin-6 (IL-6) CSF concentrations were assessed. Consecutively, the CSF concentrations of TGF beta-1 and PC1NP were compared between the different groups.
RESULTS: Median CSF concentrations of IL-6 were low and did not differ between groups. Median CSF concentrations of PC1NP were significantly lower in group A (median: 180 ng/ml, range 90-808) than in group C (median: 1,060, range 396-1194; p=0.002). TGF beta-1 concentrations were significantly higher in group C (median 355 pg/ml, range 129-843) than in groups A (median 103, range 78-675 pg/ml) and B (median 120 pg/ml, range 91-188; p=0.01 and 0.03, respectively).
CONCLUSIONS: In neonatal posthaemorrhagic HC, high concentrations of malabsorption-related biomarkers contrast with lower concentrations in SB and non-haemorrhagic triventricular HC. During the early development of high pressure HC in SB neonates, CSF biomarkers strongly indicate that CSF obstruction contributes more to the development of HC than malabsorption.