A comprehensive study of the surgical biopsy material in cases of differential diagnosis of tuberculosis and mycobacteriosis including histological, cultural and molecular studies of tissue samples makes it possible to diagnose pulmonary mycobacteriosis caused by NTMB not previously established by other methods.

The possibility of diagnosing mycobacteriosis based on the molecular genetic testing of paraffin blocks of histological biomaterial by the LPA method (DNA hybridization with linear probes) (GenoType Mycobacterium CM / AS) has been shown.

The histological changes of the inflammatory process in pulmonary mycobacteriosis were characterized by a spectrum of various tissue changes similar to those in tuberculosis with the formation of foci of caseous necrosis, epithelioid-giant cell and macrophage granulomas with the development of fibrosis and lymphocytic infiltration.