Tuberculosis Basics

Tuberculosis (TB) is caused by Mycobacterium tuberculosis. Inhaled bacteria reach the lungs and are taken up by alveolar macrophages. The immune response may clear the bacteria, contain them as TB infection without disease, or fail to contain them so that TB disease develops. An estimated 5–10% of people infected with M. tuberculosis develop TB disease during their lifetime, with the highest risk in the first 2 years after exposure. TB infection and TB disease are not interchangeable. A person with contained TB infection has no symptoms from TB and does not transmit the bacteria. TB disease reflects tissue involvement and may be symptomatic. Subclinical TB disease can be detected by microbiological testing or imaging even when symptoms are absent, and it is likely transmissible; a well appearance therefore does not establish that a person is non-infectious. The RPN’s contribution is to recognize a concerning pattern, begin facility airborne precautions promptly, complete ordered assessments and treatment safely, trend response and adverse effects, reinforce adherence, document findings and actions, and communicate changes to the most responsible provider and infection prevention and control...