[Comparative estimation of tuberculin reactions using a ruler and thermographic film followed by histological examination of the papule in guinea pigs].

The time course of tuberculin reactions during isoniazid treatment was studied on 10 guinea pigs with experimental tuberculosis. Linear, temperature and histological characteristics of papules were investigated. Thermographic estimation of papules was performed with cholesteric liquid crystal films. For pathohistological examination a new histochemical method developed at the Kiev Research Institute of Phthisiology and pulmonology on the basis of trimethine dyes of the oxanol class of organic solvents (with PK-144) was used along with the routine procedures. A decrease in the temperature gradient (difference of temperatures over papules and the symmetric areas of the skin on the other side of the animal body) was stated irrespective of the papule linear size. The thermographic method for estimating tuberculin reactions based on pathophysiological processes in papules during isoniazid treatment for 2.5 months proved to be a finer procedure for evaluating tuberculin papules than measuring their linear size.