Antimicrobials USMLE Step 1 Practice Question
A 42-year-old man with newly diagnosed HIV infection presents to clinic for initiation of antiretroviral therapy. CD4+ count is 150 cells/μL, and viral load is 180,000 copies/mL. He has no prior opportunistic infections and physical examination is unremarkable. He is started on efavirenz 600 mg daily, tenofovir 300 mg daily, and emtricitabine 200 mg daily. On day 2 of therapy, the patient reports dizziness, vivid nightmares, and difficulty concentrating at work. He denies fever, headache, visual changes, or focal neurologic deficits. Vital signs are stable: BP 122/78 mmHg, HR 82/min, RR 16/min, temperature 37.1°C. CSF studies are not obtained. Which of the following is the most likely explanation for this patient's neuropsychiatric symptoms?
Answer choices
- AEfavirenz neurotoxicity; symptoms typically improve with continued therapy or dose adjustmentCorrect answer
- BImmune reconstitution inflammatory syndrome affecting the central nervous system
- CCytomegalovirus ventricoencephalitis requiring immediate empiric antiviral therapy
- DEmtricitabine-induced peripheral neuropathy progressing to CNS involvement
- ETenofovir-associated renal dysfunction with secondary metabolic encephalopathy
- FAcute hepatitis B reactivation with hepatic encephalopathy
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