tuberculin test [L, tuber + testum, crucible] , a test to determine past or present tuberculosis infection based on a positive skin reaction, using one of several methods. A purified protein derivative of tubercle bacilli, called tuberculin, is introduced into the skin by scratch, puncture, or intradermal injection. If a raised, red, or hard zone forms surrounding the tuberculin test site, the person is said to be sensitive to tuberculin, and the test is read as positive. However, a negative tuberculin reaction does not rule out a diagnosis of previous or active tuberculosis. Sputum and gastric cultures, acid-fast staining, and x-ray studies often are needed to establish a diagnosis of tuberculosis. Kinds include Heaf test, Mantoux test, Pirquet’s test, tine test.