Postcovid syndrome: risk factors, pathogenesis, diagnosis and treatment of patients with respiratory damage after COVID-19 (overview)

In COVID-19 of moderate to severe degree, there are significant inflammatory changes in the lungs and other organs involved in the pathological process with corresponding symptoms and functional disorders lasting longer than 12 weeks. They are designated as postcovid syndrome (PCS) and require further treatment. The article presents the pathogenetic mechanism of PCS, in which organ damage has the systemic nature. Special attention is paid to the changes in the organs of the respiratory system (atelectasis in the alveoli within the lungs, remodeling of the bronchial epithelium, hyaluronan deposition in the lumen of alveoli, bronchi and perialveolar interstitial with the formation of connective tissue), which in the long term lead to fibrous changes, especially in patients with severe COVID-19 and concomitant respiratory diseases. This, in turn, makes oxygen and carbon dioxide to pass through the alveoli wall with difficulties, decreases exercise tolerance and life quality, and increases mortality in elderly patients. The article also outlines the main directions of pathogenetically conditioned therapy of patients with respiratory disorder in the outpatient settings, providing a decrease in rehabilitation period and improving the patients condition. KEYWORDS: postcovid syndrome, alveolar epithelium, atelectasis, comorbidity, rehabilitation. FOR CITATION: Bilichenko T.N. Postcovid syndrome: risk factors, pathogenesis, diagnosis and treatment of patients with respiratory damage after COVID-19 (overview). Russian Medical Inquiry. 2022;6(7):367–375 (in Russ.). DOI: 10.32364/2587-6821-2022-6-7-367-375.