a branch of medicine concerned with the causes, development, clinical and morphological manifestations, treatment, epidemiology, and prevention of tuberculosis. In the USSR phthisiology is an independent discipline that evolved from internal medicine. State medical and research establishments that also functioned as centers for the control of tuberculosis were founded as early as 1917. They developed into a network of tuberculosis clinics, sanatoriums, hospitals, and research institutes engaged in improving the diagnosis, prevention, and treatment of various forms of tuberculosis and in elaborating the theoretical basis of phthisiology. There are several specialized fields, for example, phthisiochemistry, phthisiopediatrics, and phthisiourology.

Phthisiologists use a variety of diagnostic methods: clinical, roentgenographic, endoscopic, biochemical, bacteriological, and immunological. Traditional therapy included hygienic and dietary regimens, sanatorium treatment, induced pneumothorax, and symptomatic treatment. In the second half of the 20th century such treatment was supplemented by the use of antituberculous agents that act specifically on the causative agent of the disease. Along with surgery (chiefly pulmonary, bone-and-joint, and urogenital), antituberculous drugs have become the principal therapeutic agents. Advances in the prevention of tuberculosis have resulted from improved economic and hygienic conditions and from special prophylactic measures, for example, immunization with BCG vaccine and chemoprophylaxis.

In 1976 there were more than 23,000 phthisiologists in the USSR. Phthisiology is taught at medical institutes, institutes for advanced medical training, tuberculosis institutes, and major general hospitals. Specialists are trained during internship, residencies, or graduate study.

The All-Union Society of Phthisiologists was founded in 1947; it belongs to the International Union Against Tuberculosis, which itself was founded in 1920. The Bulletin of the International Union Against Tuberculosis has been published in Paris since 1924. International conferences have been held since 1888; the 21st conference was held in Moscow in 1971. The Soviet journal Problemy tuberkuleza has been published since 1923; there also are numerous clinical journals that discuss various aspects of phthisiology. Outside the USSR the subject is discussed in journals specializing in respiratory diseases.