Original ArticleClusterin, a New Cerebrospinal Fluid Biomarker in Severe Subarachnoid Hemorrhage: A Pilot Study

BackgroundInflammation following subarachnoid hemorrhage (SAH) involves numerous mediators with biomarker properties. Preliminary studies indicated that clusterin, a multifunctional chaperon protein, was a potential biomarker in SAH. We aimed to clarify the status of clusterin in SAH.MethodsFrom 27 patients with severe SAH, 47 cerebrospinal fluid (CSF) samples were collected 0-3, 5-7, and 10-14 days after SAH. Control CSF was collected from 25 age- and sex-matched healthy control subjects undergoing spinal anesthesia for minor surgery. Clusterin concentrations were assayed using enzyme-linked immunosorbent assay and compared with inflammatory markers, imaging findings, and treatment outcome.ResultsIn healthy control subjects, mean CSF clusterin level (1908.5 ng/mL ± 36.0) was significantly higher than in the patient group (P < 0.001). In the patient group, mean clusterin level was 741.1 ng/mL ± 759.2 0-3 days, 601.6 ng/mL ± 507.2 5-7 days, and 639.2 ng/mL ± 446.8 10-14 days after SAH. Clusterin level failed to differentiate between good (Glasgow Outcome Scale 4-5) and poor (Glasgow Outcome Scale 1-3) outcomes 0-3 days and 10-14 days after SAH (P = 0.238 and P = 0.225), but significantly higher levels of CSF clusterin were found 5-7 days after SAH in patients with good outcome (P = 0.017). There was a significant correlation between CSF clusterin level 5-7 days after SAH and Glasgow Outcome Scale at 3 months (correlation coefficient = 0.633). The best correlation was found for World Federation of Neurological Societies scale (correlation coefficient = −0.741).ConclusionsSAH is associated with immediate decrease in CSF clusterin concentrations. Clusterin level at one point was a good predictor of outcome, and it may serve as a biomarker.