Tuberculosis Preventive Treatment

Some individuals exposed to Mycobacterium tuberculosis develop a latent infection and remain at a lifelong risk of developing tuberculosis (TB) disease, a state called as TB infection (TBI). TB preventive treatment (TPT) aims to treat TBI and prevent progression to active TB in an exposed or infected person. Currently, it is not possible to confirm TBI microbiologically, but can be identified indirectly by means of immune-based tests [Tuberculin skin test (TST), interferon-gamma release assays (IGRAs)]. It is crucial to rule out active TB before initiating TPT. TPT regimens have evolved with time. The most widely used regimen is 6 mo of daily Isoniazid (INH) (6H). Another regime in pipeline for persons >2 y, but not yet widely available, is 3HP (3 mo of weekly Isoniazid and Rifapentine). TPT to contacts of drug resistant TB (DR-TB) patients needs to be tailored depending on the resistance pattern in the index case, and relies on a bacteriological confirmation of the same. Individuals receiving TPT should be closely monitored for emergence of any signs or symptoms suggestive of active TB disease while on TPT.