It's not a berry aneurysm, or a subarachnoid haemorrhage.

A berry aneurysm tends to cause problems when it bursts, causing a subarachnoid haemmorhage which is immediately fatal in 30% of cases. The patient is likely to collapse when the aneurysm bursts, but would previously be fine, and would not have bacteria in his CSF - he'd have blood in it from the rupture.

You're in the right system, though...