Tuberculosis Diagnosis Adults and Children

Publication Date: December 8, 2016

Key Points

Key Points

TB disease remains one of the major causes of morbidity and mortality in the world.

The emergence of drug-resistant tuberculosis has become apparent over the past 2 decades—in particular, multidrug-resistant tuberculosis (MDR-TB; resistant to isoniazid and rifampin) and extensively drug-resistant tuberculosis (XDR-TB; resistant to isoniazid and rifampin, plus any fluoroquinolone and at least 1 of 3 injectable second-line drugs [ie, amikacin, kanamycin, or capreomycin]).

Transmission

  • Mycobacterium tuberculosis (Mtb) is transmitted from person to person via the airborne route. Several factors determine the probability of Mtb transmission:
    1. Infectiousness of the source patient: A positive sputum smear for acid-fast bacilli (AFB) or a cavity on chest radiograph are strongly associated with infectiousness.
    2. Host susceptibility of the contact.
    3. Duration of exposure of the contact to the source patient.
    4. The environment in which the exposure takes place. A small, poorly ventilated space provides the highest risk.
    5. Infectiousness of the Mtb strain.
  • Those who are household contacts and are exposed to patients who are smear positive have higher rates of both infection and disease.
  • Medical procedures that generate aerosols of respiratory secretions, such as sputum induction and bronchoscopy, entail significant risk for Mtb transmission unless proper precautions are taken.

Diagnosis

...agnosi...

...ng for Latent Tuberculosis Infection (LT...

...ends performing an interferon-γ release...

...anel suggests performing an IGRA ra...

...anel suggests performing an IGRA instead...

...e panel suggests a second diagnostic...

...gests performing a TST rather than an IGRA in heal...


...sting for TB Diseas...

...e panel recommends that acid-fast...

...ts that both liquid and solid mycobacterial c...

...anel suggests performing a diagnostic nucleic acid...

...commends performing rapid molecular drug sus...

...uggests mycobacterial culture of respiratory...

...he panel suggests sputum induction rat...

...ts flexible bronchoscopic sampling, rather...

The panel suggests that postbronchoscopy...

...panel suggests flexible bronchoscopic sampl...

...el suggests that cell counts and chemi...

...l suggests that adenosine deaminase levels be...

...suggests that free IFN-γ levels b...

...he panel suggests that AFB smear microscopy...

...ecommends that mycobacterial cultures be perf...

...suggests that NAAT be performed, rather...

...suggests that histological examination b...

...recommends a culture isolate from each...

...ial Laboratory Tests for the Detection of MtbHa...

...gure 1. Paradigm for Evaluation of Those wit...

...Summary of Recommendations for Testing for LT...