2nd August 2023

A 42-year-old man presents with new onset confusion and drowsiness.

A 42-year-old man presents with new onset confusion and drowsiness. His husband states that he has not been his usual self the past week, complaining of severe headaches. He has a past medical history of HIV. Examination reveals a reduced GCS and neurological examination is difficult to perform due to the patient’s inability to cooperate. An urgent CT head reveals multiple ring-enhancing lesions.

What is the most likely diagnosis?

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