Antimicrobials USMLE Step 1 Practice Question
A 42-year-old man with active pulmonary tuberculosis is on antimicrobial therapy. After 6 weeks of treatment, he develops progressive numbness and tingling in his feet bilaterally. Vital signs are stable (BP 128/82, HR 78, RR 16, Temp 37°C). Physical examination reveals diminished ankle reflexes; chest X-ray shows improvement in infiltrates. Serum pyridoxine level is low at 8 ng/mL. He denies alcohol use. His physician adds pyridoxine supplementation. Which tuberculosis drug most likely caused this peripheral neuropathy?
Answer choices
- ARifampin
- BIsoniazidCorrect answer
- CStreptomycin
- DPyrazinamide
- EEthambutol
- FThiacetazone
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