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What is A 35 year old man has a headache , sleepiness, and poor balance that have worsened over the past week. The patient is known to be HIV - seropositive. On examination, his responses are slow and he has some difficulty in sustaining attention. He has right hemiparesis with increased reflexes on the right. Routine cell counts and chemistries are normal. What is the most appropriate next step? and explain in detail?
Always we should look for an infectious or malignant mass with a contrast enhanced CT,  non - contrast head CT is less sensitive. Antiretroviral therapy is of only long term benefit not for treatment of acute problem.since embolic stroke is unlikely in this case, i.v heparin is not the immediate need before further evaluation.