Association between elevated cerebrospinal fluid D-dimer levels and delayed cerebral ischaemia after aneurysmal subarachnoid haemorrhage.

Delayed cerebral ischaemia (DCI) after aneurysmal subarachnoid haemorrhage (aSAH) is a major contributor to morbidity and mortality. It is currently not possible to reliably predict patients at risk of DCI after aSAH. The aim of this study was to quantify cerebrospinal fluid (CSF) D-Dimer and plasminogen levels and to investigate any association with development of DCI. Cerebrospinal fluid (CSF) samples collected from 30 patients within 72 h post-aSAH (n = 13 DCI and n = 17 non-DCI patients) were analysed. DCI was diagnosed when angiographic vasospasm was detected in the presence of new onset neurological deficit. Enzyme-linked immunosorbent assays were used to quantify D-dimer concentrations while western blotting was used to quantify plasminogen levels. Significant differences in CSF proteins between DCI and non-DCI cohorts were verified using Mann-Whitney test. Sensitivity and specificity of these proteins for detecting DCI was examined using a ROC curve and verified with a Fischer's exact test. CSF levels of D-dimer within 72 h post aSAH were significantly elevated in DCI patients (54.29 ng/ml, 25.35-105.88 ng/ml) compared to non-DCI patients (26.75 ng/ml, 6.9-45.08 ng/ml) [p = 0.03]. In our sample population, D-dimer levels above 41.1 ng/ml had a sensitivity of 69.2% and specificity of 75% for predicting DCI. CSF levels of plasminogen (DCI: 0.50 signal-intensity/μl, 0.20-0.73 signal-intensity/μl, non-DCI: 0.28 signal-intensity/μl, 0.22-0.54 signal-intensity/μl) did not differ between the DCI and non-DCI cohort (p > 0.05). Our study suggests that elevated D-dimer in the first 72 h after aSAH may be a potential predictive biomarker for DCI. Crown