Background Subarachnoid hemorrhage (SAH) is a life threatening and disabling condition. Approximately 70% of patients die or require long â term assisted care due to neurological impairment. First 72 hours of brain injury are crucial for tissue oxygenation, which predicts patient survival. An inflammatory marker, HMGB1 protein, was found to be strongly involved in long term repair and defense programs in cerebral ischemia. The purpose of this study was to evaluate HMGB1 concentration in cerebrospinal fluid and determine the correlation with treatment outcome of SAH patients. Connection between clinical status, inflammatory markers, and imaging studies were also investigated. Methods Thirteen patients (8 females, 5 males), mean age of 57 years (range from 41 to 79 years) with subarachnoid hemorrhage underwent external ventricular drain placement in order to treat acute hydrocephalus. The CSF samples were taken randomly within 3 weeks of their intensive care unit (ICU) stay. Total number of 32 samples was collected. Control group of eight patients (5 females, 3 males), mean age of 53 (range from 31 to 77 years) with minor, non-inflammatory neurological disorders, underwent lumbar puncture procedure. CSF samples from both groups were blindly examined for HMGB1 concentration twice. ELISA kit with detection range from 0.2 to 10 ng/mL was used. Correlation between HMGB1 and other patients parameters i.e. CRP, fibrinogen, WBC, body temperature, Fisher CT an modified Fisher CT scale score were examined in study group then with GOS at 3 month. Statistical analysis was performed with Statistica 10 by StatSoft Inc. Results CSF level of HMGB1 concentration significantly differs between control (mean 0,1 ng/mL) and study group (mean 5,9 ng/mL). HMGB1 level statistical analysis has a Speraman's correlation of -0,88 with treatment outcome. No significant correlation between other examined patient parameters and clinical status was found. In our study HMGB1 have a strongest correlation with treatment outcome of all examined parameters. Single patients present decreasing trend in HMGB1 concentration during they ICU stay. Conclusion Predicting factors of late neurological deterioration in subarachnoid hemorrhage on admission can be used to evaluate patient progress. From our investigation, HMGB1 concentration in CSF was found to be most helpful in predicting treatment outcome early in SAH patients. revealed that the cell line was positive for CD105, Ki67, and Vimentin. The optimal mitochondrial and glycolytic flux parameters were reported at 20.000 cells/well, resulting that this seeding density will be used in our further experiments.