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Latent tuberculosis — USMLE Step 3 MCQ

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HardInternal Medicine (chronic management)Latent tuberculosisUSMLE Step 3

A 24-week pregnant patient has a positive interferon-gamma release assay after recent household exposure to contagious tuberculosis. Chest radiography is normal and active disease is excluded. Treatment should begin during pregnancy because exposure was recent. Which regimen should be avoided specifically because of pregnancy?

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Correct answer: C — Once-weekly isoniazid plus rifapentine for 3 months

The best answer is “Once-weekly isoniazid plus rifapentine for 3 months”. CDC does not recommend the 3HP isoniazid-rifapentine regimen during pregnancy or when pregnancy is expected during treatment because safety has not been established. Other regimens require individualized toxicity and interaction review. Short-course rifamycin regimens are preferred, but once-weekly isoniazid-rifapentine for 3 months is not recommended during pregnancy or when pregnancy is expected during treatment.

Reference: CDC: Treatment for Latent Tuberculosis Infection: https://www.cdc.gov/tb/hcp/treatment/latent-tuberculosis-infection.html