Tissue kallikrein: A potential serum biomarker to predict delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage.

ABSTRACT

BACKGROUND: Delayed cerebral ischemia (DCI) is a severe complication after aneurysmal subarachnoid hemorrhage (aSAH). Tissue kallikrein (TK), a subgroup of serine proteinases, is an important component of the kallikrein-kinin system. Exogenous TK attenuated cerebral vasospasm in a rabbit model of subarachnoid hemorrhage. We intended to discern association of serum TK levels with aSAH-related DCI. METHODS: Serum TK levels were detected in a total of 92 aSAH patients and 92 healthy controls. A multivariate logistic regression model was configured to investigate relationship between TK levels and occurrence of DCI. RESULTS: TK levels were substantially lower in aSAH patients than in controls. TK levels were strongly correlated with World Federation of Neurological Surgeons (WFNS) score and modified Fisher score. Serum TK, WFNS score and modified Fisher score retained as the three independent predictors for DCI. Under receiver operating characteristic curve, predictive capability of TK levels was in the range of WFNS score and modified Fisher score, as well as TK levels could remarkably improve predictive abilities of WFNS score and modified Fisher score. CONCLUSIONS: Serum TK emerges as a potential biomarker for assessment of hemorrhagic severity and prediction of DCI following aSAH.