A 28-year-old HIV-positive man with CD4 count 42 cells/µL has a new headache and is found to have a single ring-enhancing lesion in the right basal ganglia on MRI. Toxoplasma IgG is positive. CSF PCR for T. gondii is positive. What empirical therapy should be started?

• A Pyrimethamine plus sulfadiazine plus leucovorin ✓
• B Trimethoprim-sulfamethoxazole (TMP-SMX) high dose
• C Clindamycin plus atovaquone
• D Azithromycin plus pyrimethamine

Explanation

Cerebral toxoplasmosis in HIV is treated with pyrimethamine (200 mg loading dose, then 75 mg/day) plus sulfadiazine (1–1.5 g every 6 hours) plus leucovorin (10–25 mg/day to prevent pyrimethamine-induced bone marrow suppression) for at least 6 weeks (acute phase). This is the standard of care per IDSA guidelines. TMP-SMX is used as prophylaxis (CD4 <100 cells/µL) and has been studied as an alternative treatment but is not the first-line therapy. Clindamycin plus pyrimethamine is an alternative for sulfa-allergic patients.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.