Advances in the diagnosis and treatment of latent tuberculosis infection.

Purpose of review This review describes the major developments in the rationale for treating latent tuberculosis infection; new approaches to identifying persons with latent infection who are most likely to progress to active disease; and the development of novel short-course regimens for treatment of latent tuberculosis. Recent findings As many as one-third of the world's population has latent infection with Mycobacterium tuberculosis. Models demonstrate that tuberculosis will not be eliminated without large-scale treatment of persons with latent TB. Current tools for identifying persons at risk for active tuberculosis disease include TST and IGRA, which have poor positive predictive values. Newer approaches using gene expression profiling show promise and are being studied in the ongoing trials. Development of short-course regimens are a major advance in treatment of latent TB. Three months of rifapentine with isoniazid, 4 months of rifampin, and 1 month of rifapentine with isoniazid have been found to be noninferior to the standard 9 months of isoniazid. Progress towards TB elimination can be accelerated by instituting public health measures that take into account new developments in identifying and treating persons with latent tuberculosis infection who are most likely to progress to active disease.