ABSTRACT
The endothelium is a tissue most vulnerable to the SARS-CoV-2 virus. Systemic endothelial dysfunction leads to the development of endothelitis which causes the main manifestations of the disease and systemic disturbance of microcirculation in various organs. Pulmonary microcirculatory damage, the most striking clinical manifestation, was the reason to perform SPECT to detect microcirculation disorders. Aim. To assess microcirculatory changes in the lungs of patients who had no previous respiratory diseases and had a COVID-19 infection at different times from the onset of the disease. Methods. SPECT data were analyzed in 136 patients who had a proven coronavirus infection of varying severity from May 2020 to June 2021. Results. All patients showed changes in microcirculation in the lungs in the post-COVID period. The severity of microcirculation disorders had a significant correlation (rs = 0.76;p = 0.01) with the degree of damage to the pulmonary parenchyma and an average correlation (rs = 0.48;p = 0.05) with the timing of the post-COVID period and the degree of residual lesions on CT (rs = 0.49;p = 0.01). The examined patients with persistent clinical complaints had pulmonary microcirculatory lesions, which may indicate the development of vasculitis, at all stages of the post-COVID period. Despite regression of the lesions confirmed by CT in 3 to 6 months after the acute COVID-19 infection, specialists from Russian and other countries report that 30–36% of patients develop pulmonary fibrosis. Similar changes were identified in 19.1% of the examined patients in our study. Conclusion. Microcirculation disorders are detected in all patients in the post-COVID period, irrespective of the severity according to CT. Progressive decrease in microcirculation in the lower parts of the lungs, local zones of hypoperfusion with the critically low accumulation of radiopharmaceuticals, persistent areas of compaction of the lung tissue (so-called “ground glass”), reticular changes, and the development of traction bronchiectasis, a decrease in the diffusion capacity of the lungs and alveolar volume may indicate fibrotic lesions with subsequent development of virus-associated interstitial lung disease. © 2021 Medical Education. All rights reserved.
ABSTRACT
Purpose. To evaluate the radiological patterns of a new COVID-19 coronavirus infection. Materials and methods. Review of literature sources. Results. COVID-19 causes the acute severe viral pneumonia. Radiological diagnostics of COVID-19 is very important, because CT can be the first study that shows the signs of viral lung lesion, and allows to assess the severity of the lesion and adverse prognostic signs of its further development. The initial CT pattern of COVID-19 is a pattern of infiltration of secondary pulmonary lobules on the type of «frosted glass» (a symptom of «dry leaf») with a subsequent decrease in the volume of lesions at favorable results, or their increase, accession of CT pattern of «cobblestone road» and the appearance in the area of «frosted glass» the alveolar infiltration in unfavorable course of disease. These symptoms are the precursors to the development of respiratory distress syndrome. At a later primary examination, the primary CT symptoms are the pattern of «cobblestone road» and areas of alveolar infiltration, which correlates with an unfavorable further course and outcome. There was noted that viral pneumonia in COVID-19 was characterized by the location of changes in the posterior subpleural and peribronchial areas. All authors confirmed that cavities, nodules, pleural and pericardial effusions, and lymphadenopathy were absent in COVID-19. In the course of observation, quantitative characteristics of the lesions with a score were proposed, the use of which can help in determining the prognosis. Also identified temporary staging of the process and the formation in some of patients the residual changes in the lungs the same as in influenza pneumonia H1N1 (2008–9гг, 2015–16.) and SARS SARS-CoV-2 (2003)which can start the process of development of progressive pulmonary fibrosis. There is a need for frequent CT studies (every 4 days) to enable timely assessment of rapid dynamics and changes in treatment tactics. The analysis of the results of the examination should be performed by at least 2 radiologists experienced in thoracic radiology, with the involvement of a third independent expert, in case of disagreement. All the authors confirmed the low information content of traditional radiography in assessing viral lung lesions. In some studies, chest radiographs were not performed, only CT as a more sensitive method for detecting early changes, similar to previous outbreaks of coronavirus. However, the role of traditional radiography was recognized as unquestionable when evaluating changes in reanimation department conditions. Conclusions. The accumulation of experience in clinical and radiological examination of COVID-19 patients allowed to determine the radiological semiotics of the process, which is important for determining the treatment tactics. ;