S-100 PROTEIN PLASMA-LEVELS AFTER ANEURYSMAL SUBARACHNOID HEMORRHAGE

We investigated the level of S-100 protein in blood as an indicator of brain damage in 71 patients suffering from subarachnoid haemorrhage ( SAH) due to ruptured aneurysms. Concentrations of S-100 protein were d etermined by micro-titre based immunofluorometic assay detecting predo minantly S-100(b) on blood samples obtained 24 hours, 3 days and 7 day s after onset of symptoms in patients with SAH and from 120 healthy co ntrol subjects. Neurological status was assessed using the Hunt and He ss (HH) scale on admission and by the Glasgow Outcome Scale (GOS) 6 mo nths later. Mean concentrations of S-100 protein in blood were signifi cantly (p < 0.0001) higher in patients 24 hours (0.263 +/- 0.387 mu g/ l), 3 days (0.192 +/- 0.288 mu g/l) and 7 days (0.256 +/- 0.442 mu g/l ) after onset of SAH symptoms compared to controls (0.050 +/- 0.081 mu g/l). More severe neurological symptoms (higher HH scale scores) on a dmission correlated with higher S-100 levels on admission (R = 0.70) a nd Day 3 (R = 0.66) (p < 0.0001). Worse outcome (low er GOS score) 6 m onths after SAH was also associated with higher plasma concentration o f S-100 in the first week after SAH. In summary, this study showed tha t in patients with SAH due to ruptured aneurysm, S-100 protein levels correlate with early neurological deficit and are as sensitive as HH s cores in predicting neurological outcome (GOS scores). Measurement of S-100 protein in blood is a reliable non-invasive method and may be cl inically useful to screen for and monitor progression of central nervo us system diseases of various origins.