[Value of different combinations of immunological signs for differential diagnosis of lung diseases].

Stemming from the results of a complex immunologic examination of 653 patients with lung diseases, 4 immunologic reactions of highly diagnostic value were identified, i. e. specific antibody formation, blast transformation with PPD and PHA and spontaneous rosette formation. The most valuable combinations of these reactions were defined for each type of the pathology. For tuberculosis, 16 such combinations were found, including 5 without specific antibody formation; 5 in cancer; 3 in nonspecific inflammation; and 1 in sarcoidosis. Diagnostically important combinations of the above immunologic reactions are summarized in the Table whose use in differential diagnosis of doubtful cases of tuberculosis, cancer, nonspecific pneumonia and sarcoidosis can increase their diagnostic probability up to 0.95-0.99 in 30 per cent of the patients without employing invasive methods.