Soluble urokinase receptor is elevated in cerebrospinal fluid from patients with purulent meningitis and is associated with fatal outcome.

The urokinase-type plasminogen activator system has been suggested to play a pathophysiological role in brain damage. The aim of this study was to evaluate CSF levels of suPAR in 183 patients clinically suspected of having meningitis on admission. Of these, 54 patients were found to have purulent meningitis, 63 had lymphocytic meningitis, 12 had encephalitis, and 54 patients were suspected of, but had no evidence of, meningitis. There was a significant difference in suPAR levels among patient groups (Kruskal Wallis test, p < 0.0001) with significantly higher CSF suPAR levels in patients with CNS infection (purulent meningitis: median suPAR 2.41 microg/l (range 0.12-35), lymphocytic meningitis: 1.10 microg/l (0.15-5.31), and encephalitis (1.77 microg/l (0.17-11.7)) than in patients without meningitis (0.64 microg/l (0-5.34) (Dunn's multiple comparison test, p < 0.05). Also, patients with purulent meningitis had significantly higher CSF suPAR levels than patients with lymphocytic meningitis (p < 0.001). Patients with purulent meningitis who died (n = 8, 4.9 microg/l (1.3-35) had significantly higher CSF levels of suPAR than patients who survived (n = 46, 2.1 microg/l (0.1-24), Mann Whitney, p = 0.046). Employing a cut-off point of 3.1 and above, the OR (95%CI) for fatal outcome was 11.9 (1.4-106), univariate logistic regression analysis, p = 0.026. In conclusion, CSF suPAR levels may be an important predictor for fatal outcome in purulent meningitis.