TB Flashcards
Who should be screened for Tb?
Household contact of or recent exposure to active case
Mycobacterial lab personnel
Immigrants from high burden countries
Homeless, incarcerated, institutionalized
What is the cutoff for tuberculin skin testing size of induration?
15 mm in most patients
5-10 mm in higher risk patients
How to treat latent Tb?
Rifapentine + Isoniazid once weekly for 3 months
OR
Rifampin once daily for 4 months
OR
Rifampin plus Isoniazid once daily for 3 months
Given via DOT (directly observed therapy)
*Alt: Isoniazid monotherapy for 6-9 months
Initial therapy for Tb?
Intensive phase for 2 months followed by maintenance phase for 4 months. Think 4 for 2, then 2 for 4. Via DOT (Directly Observed Therapy). Can be via video.
Intensive: RIPE (Rifampin, Isoniazid, Pyrazinamide, Ethambutol) for 2 months
Maintenance: Isoniazid + Rifampin
- Given daily is prefered, but M-F or Thrice weekly are acceptable
What Rifamycin can be used if you want to avoid rifampin due to drug interaction concerns (treating TB)?
Rifabutin
*Rifampin is a strong induce of 3A4, and also a susbtrate
What if you are taking a protease inhibitor for HIV (e.g. Darunavir) and you need RICE therapy?
Substitute Rifabutin for Rifampin to avoid drug interaction.
What should you give with Isoniazid to reduce neurotoxicities? (periph neuropathies, and other toxicitiies)
Pyridoxine (50 mg daily)
What if you start intensive therapy for Tb, but sputum cultures are still positive after 2 months?
Still switch to continuation phase, but extend to 7 months instead of 4 months.
When is Tb therapy considered “failed”?
After 4 months of treatment (2 months intensive, then 2 months continuation), and still getting positive cultures.
What if there’s skeletal or CNS involvement with Tb infection?
Longer continuation phase (RI), 7-10 months.
