Cytokine levels in cerebrospinal fluid and delayed ischemic deficits in patients with aneurysmal subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) induces an inflammatory reaction and may lead to ischemic brain damage. The pathogenesis of brain dysfunction and delayed ischemic symptoms remain difficult to understand despite extensive surveys of such reactions. Cytokine production in the central nervous system following SAH and its relation with clinical outcome have hardly been studied. This study was aimed to determine whether the levels of IL-1 beta, IL-6 and TNF-alpha in the initial cerebrospinal fluid would increase following aneurysmal SAH, and be related with development of delayed ischemic deficit and clinical outcome. Nineteen patients suffering from aneurysmal SAH and 12 control volunteers were the subjects in this study. Cerebrospinal fluid samples were obtained on admission and the levels of each cytokine were determined with enzyme-linked immunosorbent assay. Patients with aneurysmal subarachnoid hemorrhage showed elevated levels of IL-1 beta, and TNF-alpha on admission. The patients with poor neurological status showed high levels of IL-1 beta, and IL-6. The patients who developed delayed ischemic deficit had high level of IL-6. We suggest that elevated level of IL-6 in cerebrospinal fluid of patients with aneurysmal SAH on admission can predict the high risk of delayed ischemic deficit.