Latent tuberculosis

This code represents a state where an individual is infected with Mycobacterium tuberculosis but does not have active tuberculosis disease. The bacteria are present in the body but are inactive, causing no symptoms and not contagious.

This code is used for patients who have a positive tuberculosis test (e.g., TST or IGRA) but no clinical, bacteriological, or radiological evidence of active disease. It is appropriate for documenting latent tuberculosis infection (LTBI) identified through screening or contact tracing.

• Do not use this code if there is any indication of active tuberculosis disease; use codes from Chapter A15-A19 instead.
• Ensure documentation clearly states "latent" or "inactive" tuberculosis, or a positive test result without active disease.
• Distinguish from nonspecific reactions to TB tests, which are coded elsewhere.