Infection in the subdural space, often present like bacterial meningitis. Can be missed on CT, especially unenhanced, or MRI as it is often just a thin rim of pus between the brain and the skull.
Drain drain drain, its an emergency.
I would avoid the penicillin/beta-lactamase inhibitors as they do not cross the blood brain barrier well.
ICD9 Codes (Soon to be supplanted by ICD10)
subdural empyema 324.9.