Latent tuberculosis infection

Asymptomatic state with positive tuberculin skin test or IGRA in the absence of active tuberculosis. Preventive therapy reduces reactivation risk by 60–90%.

ICD-10 Z22.71 drug

Also known as: LTBI, Latent TB

Drugs used for this condition

ARifampicinFirst line · Antituberculous antibioticRifampicin 600 mg daily for 4 months (4R) is one of the preferred regimens for latent tuberculosis infection. CDC 2020 lists 4R alongside 3HP (isoniazid + rifapentine for 12 weeks) and 3HR (isoniazid + rifampicin for 3 months), favoring these over isoniazid monotherapy for 9 months in terms of tolerability and completion. Efficacy is 80–90% with proper course completion.

How to read tiers A–F

Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.

AStrong evidence – first or second line in international guidelines
BRecommended in selected cases
CStudy data contradict each other
DBenefit not proven, no documented harm
FDocumented harm, or risk without benefit