Electron Microscopic Characteristics of The Blood-Air Barrier Interstitium in Fibrous Cavernous Pulmonary Tuberculosis in Comparison with Chronic Nonspecifi c Lung Diseases

Abstract

Aim. To describe the ultrastructural characteristics of the blood-air barrier (BAB) interstitium in fi brous cavernous pulmonary tuberculosis (FCT) in comparison with chronic nonspecifi c lung diseases (CNSLD).Materials and methods. The fragments of the pericavernal zone and lung tissue were taken for the study at the resection border from the dead or operated for CNSLD persons (n = 163), and the perifocal and boundary zone of lung tissue. 116 CNSLD patients were divided into 3 subgroups: 1) chronic lung abscess (n = 42); 2) bronchiectasis (n = 44); 3) lung cyst (n = 30). The lung fragments of 30 patients who died from pathology not associated with lung diseases (myocardial infarction, acute cerebrovascular accident) were used as a control group to compare the morphological parameters. The criteria for inclusion of patients in the study: age from 18 to 65 years, negative clinical and laboratory data on the presence of comorbid pathology (viral hepatitis B, C and HIV). For TEM, lung fragments 1×1×1 mm in size were cut out and fi xed in a 2.5% glutaraldehyde solution in phosphate buffer (pH = 7.2–7.4) and washed in 0.1 M phosphate buffer (pH = 7.4), followed by dehydration in alcohols of an ascending concentration and placing in a mixture of Epon and Araldite resins according to the scheme. Ultrathin sections were made with Reynolds staining. Viewing and photographing preparations was carried out on a PEM-100 transmission electron microscope (Ukraine) (magnifi cation range from ×1000 to ×30 000). Results. It was established that changes in BAB components in all groups had similar features in the form of severe interstitial fi brosis, the signs of endothelial cell degeneration and destruction of varying degrees of severity, as well as the heterogeneity of the endothelial and epithelial basement membranes.Conclusion. Ultrastructural changes in the BAB components of the removed lung part in patients with FCT and chronic nonspecifi c lung diseases are characterised by a polymorphism with prevailing dystrophic and destructive changes in the perifocal zone of infl ammation, and compensatory-adaptive processes on the peripheral, especially at the resection border.