Morphometric studies were carried out in 50 patients who died of MM, 40 of them died with signs of renal failure and 10 with no signs of CRF. When performing a morphometric study of the lungs and bronchi, a comparative analysis was conducted with similar indicators of 30 absolutely healthy people, equivalent in age and sex, who died from injuries incompatible with life, and did not have a history of hemoblastosis and bronchopulmonary pathology (control group) .
A morphological study of the bronchi of different caliber in MM patients showed an increase in the number of neutrophils, eosinophils, lymphocytes, plasma and mast cells. Morphometric parameters of segmental bronchi are given. In most patients with MM, the height of the epithelium of the mucous membrane of the segmental bronchi is reduced, compared to the same indicator in the control, and a decrease in the thickness of the mucous membrane is diagnosed. In some patients, thinning of the basement membrane was noted, and growth of connective tissue in the submucosal layer.
Due to edema, lymphoid and plasma cell infiltration, an increase in the thickness of the interalveolar septa was observed in MM patients who died without renal failure – 59 ± 5.5 μm (P <0.001). In patients with MM who died in the presence of renal insufficiency, calcification, symptoms of uremic pneumonitis and edema of the interstitial lung tissue were associated with the above pathological processes, therefore the thickness of the alveolar partitions was even greater (80.3 ± 10 μm; P <0.001). In the control, this indicator is 40 ± 0.08 microns.
The reduction in the area of part of the alveoli in patients with MM who died without CKD phenomena (95 ± 8 μm 2 ; P <0.01) is associated with a thickening of the interalveolar septa, manifestations of pulmonary paraproteinosis, and changes in the bronchi and blood vessels. In the presence of chronic kidney disease, swelling of the lung stroma, calcification, uremic pneumonitis. Therefore, in chronic renal failure, changes in the affected alveoli are more pronounced (area – 71.7 ± 5.5 μm 2 ; P <0.001). In the remaining parts of the lung, a compensatory expansion of the alveoli was observed (181 ± 15 μm 2 ; P <0.05).
In patients with MM with a pronounced osteo-destructive process of the chest and CRF (stage IIIA and stage II, stage IIIB), changes in the diaphragm were observed that were absent in the control group. Myocytes of medium size prevailed, but at the same time, the number of large and small myocytes increased. In these patients, a significant growth of the stroma around the vessels, in the intramuscular space, and large areas of lipomatosis were detected. The development of morphological changes in the diaphragm in patients with MM is promoted by its lymphoid and plasma cell infiltration, the presence of protein stasis in small vessels with impaired microhemocirculation and a decrease in the contractile ability of the diaphragm. In the presence of renal failure, uremic damage and edema of the diaphragmatic muscle also contribute to dystrophic changes. .
Direct radiographic signs of specific myelomatous lesion of the lungs (the presence of paraproteinosis of the lungs, amyloidosis, plasma cell and lymphoid infiltration) could not be detected in any patient, since they rarely reach such marked sizes when they can be determined radiographically. However, when carrying out the proposed complex of additional instrumental studies with a high degree of probability, it can be concluded that there is a specific myelomatosis lesion of the lungs. In order to identify statistically significant indicators that could indicate the presence of myelomatous lesions of the bronchopulmonary system, discriminant analysis was performed. In the study accompanying these patients instrumental examination of the bronchopulmonary system,after autopsy, morphological changes in the lungs and bronchi are studied. The results of the discriminant analysis are as follows.