NEW METHODS IN MEASURING TUBERCULIN SENSITIVITY

Abstract

Intracutaneous test with “purified protein derivate” /PPD/ of the tbc bacillus are generally as satisfying for most clinical purposes. In many occasions, however, more accurate methods, are needed. This is especially obvious in clinical research. We have made a comparative study using three different methods in measuring tuberculin hypersensitivity: 1.The classic Mantoux test with PPD, 2.Mantoux test+thermographic measurement of the skin reaction, 3.In vitro test in lymphocyte cultures using PPD as immunogen. The number of PPD sensitive cells was compared with that of PHA reactive cells /total number of T lymphocytes./Following conclusions was drawn from the results: 1.The two first mentioned methods are semiquantitative. 2.The thermograph is a useful tool in the clinical characterization of the cellmediated immune reaction in the skin. 3.The in vitro test is by far the most accurate method in measuring tuberculin sensitivity. We emphasize, that the in vitro test should be carried in all occasions when the patient is expected to show a weak reaction to tuberculin or when quantitative data are needed for clinical or scientific purposes.