Medical histories of 244 new cases of infiltrative tuberculosis of the lung were studied. The age of the patients was over 50 years. It was revealed that in the majority of the patients (118 persons, 48.4 per cent) the disease was detected on their taking medical advice and 72.9 per cent (86 subjects of them) had destructive lesions in the lungs. Planned fluorographic examinations revealed such a form of pulmonary tuberculosis less frequently (96 persons, 39.3 per cent) and detection of destructive lesions in them amounted to 63.5 per cent (61 out of 96 persons). In 57.4 per cent of the patients (140 out of 244) concomitant pathological processes in the viscera were detected. 66.4 per cent of them had destructions in the lung tissue.