Advanced age, symptoms lasting more than 24 h before hospital presentation, absence of otitis or sinusitis, diabetes mellitus, alcoholism, absence of fever, absence of headache, elevated heart rate, low diastolic blood pressure, low GCS score, cranial nerve palsy, seizures, focal neurological deficits at admission, elevated CRP levels in blood, low thrombocyte count in blood, low CSF leukocyte count, low CSF-to-blood glucose ratio, and elevated CSF protein levels were all associated with unfavourable outcome. Here, CRP is linked to sinusitis.