Tumor necrosis factor alpha serum levels and inflammatory response in acute ischemic stroke.

OBJECTIVE To assess the implication of tumor necrosis factor alpha (TNF-alpha) and interleukine-6 (IL-6) in acute ischemic stroke and to correlate this with lesion size, vascular risk factors, and neurological impairment. METHODS We included 70 patients consecutively admitted to the Department of 1st Neurology, Haydarpasa Numune Educational and Research Hospital, Istanbul, Turkey, between September 2001 and April 2002, with first-ever ischemic cerebral infarction within the first 24 hours from onset. The TNF-alpha, IL-6, fibrinogen, C-reactive protein, erythrocyte sedimentation rate (ESR) and leukocytes were determined in plasma on admission. Neurological impairment was evaluated with the modified Rankin Scale. RESULTS We found higher baseline levels of TNF-alpha and IL-6 in the plasma of patients with acute ischemic stroke and neurological impairment in comparison to control subjects. In the large infarct group, TNF-alpha, IL-6, low-density lipoprotein-cholesterol and fibrinogen were found significantly higher compared to the small infarct group. While an association between TNF-alpha and IL-6 values and lesion size were determined, no relation was found between localization and etiology. The TNF-alpha level was found to be in positive correlation with IL-6, fibrinogen, and ESR. The IL-6 level was found to be in positive correlation with ESR fibrinogen, and leukocytes. CONCLUSION Inflammatory findings are associated with the early stage of ischemic stroke. The TNF-alpha and IL-6 were also higher in patients with clinical worsening. The release of proinflammatory cytokines after focal cerebral ischemia indicates a step leading to tissue necrosis or reflects the amount of ischemic brain injury, since the higher concentrations of TNF-alpha and IL-6 are found in patients with large infarctions.