tuberculosis testAny of a number of tests used to detect past exposure to, or current infection by M tuberculosis. See Mantoux test, Tuberculin skin test.
1. Tests that document current infection, either by a direct smear of sputum, or by culturing a specimen, eg sputum, lymph node, lung biopsy; M tuberculosis, is notoriously slow to grow, requiring 3+ weeks for definitive identification when cultured in the traditional fashion; more recently, molecular techniques, eg PCR-have been used to shorten the turnaround time for test results
2. Tests that evaluate the immune response, see Mantoux test, Tuberculin test.
Obsolete TTs include colorimetric tests–once believed to measure substance(s) seen in ↑ amounts in Pts with TB, the mirror test and theurorosein test; other TTs, eg the tine and Sterneedle tests, that measure sensitivity to tuberculin, reflect the Pt's immune status, and have been abandoned.