Cerebral abscess is one of a number of differential for a ring enhancing lesion in the brain.

The avid diffusion restriction makes an abscess highly likely, despite this patient had no fever or raised WCC. The immune response may be suppressed.

MR spectroscopy could have been performed to add further weight to the diagnosis.

Neurosurgery was performed. The final microbiological analysis identified the causative organism as Staphylococcus aureus.