Expression of cellular retinoic acid-binding protein-I (CRABP-I) in the cerebrospinal fluid of adult onset moyamoya disease and its association with clinical presentation and postoperative haemodynamic change

Objective The elevation of cellular retinoic acid-binding protein-I (CRABP-I) has been suggested as a candidate in the pathogenesis of paediatric moyamoya disease (MMD). However, few studies have addressed CRABP-I in adult onset MMD. The aim of this study was to examine the expression of CRABP-I in the cerebrospinal fluid (CSF) of adult onset MMD, and to evaluate its association with clinical presentation and postoperative haemodynamic change. Methods This study examined the CSF from 103 patients: bilateral MMD, n= 58 (56.3%); unilateral MMD, n= 19 (18.4%); atherosclerotic cerebrovascular disease (ACVD), n= 21 (20.4%); and control group, n= 5 (4.9%). The intensity of CRABP-I was confirmed by western blotting and expressed as the median (25th-75th percentile). The differences in CRABP-I expression according to disease entity (unilateral MMD vs bilateral MMD vs ACVD), initial presenting symptoms (haemorrhage vs ischaemia) and postoperative haemodynamic change (vascular reserve in single photon emission CT and basal collateral vessels in digital subtraction angiography) were analysed. Results CRABP-I intensities in bilateral MMD (1.45 (0.86-2.52)) were significantly higher than in unilateral MMD (0.91(0.78-1.20)) (p=0.044) or ACVD (0.85 (0.66-1.11)) (p= 0.004). No significant differences were noted based on the initial presenting symptoms (p= 0.687). CRABP-I was not associated with improvement in vascular reserve (p= 0.327), but with decrease in basal collateral vessels (p= 0.023) postoperatively. Conclusions Higher CRABP-I in the CSF can be associated with typical bilateral MMD pathogenesis in adults. Additionally, postoperative basal collateral change may be related to the degree of CRABP-I expression.