ABSTRACT
Introduction. COVID-19 is a highly contagious infectious disease caused by the novel coronavirus SARS-CoV-2. After the acute phase and discharge from the hospital, convalescent people continue to have respiratory symptoms, changes in pulmonary function (PF) and indicators of chest computed tomography (CT). Aim. To evaluate changes in PF and quantitative CT data in patients after severe coronavirus pneumonia. Materials and methods. A cross-sectional observational study was conducted: 55 patients (including 28 men, aged 32–78 years) with a diagnosis of “lung interstitial process due to a coronavirus infection” were examined. All patients underwent a study of PF (spirometry, body plethysmography, measurement of the diffusion lung capacity: DLCO ) in the interval of 24–305 days after discharge from the hospital. CT scan of the chest was performed simultaneously with the functional examination (±30 days), the parameters were calculated: ground glass areas, functional lung tissue volume (FV), affected tissue volume (AV), CovidQ (AV/FV ratio). Results. A decrease in DLCO was found in 28 patients. Restrictive disorders – in 13 patients, obstructive disorders – in 2 patients. At the time of the CT examination, all patients had residual changes in both lungs of varying severity. Functional parameters (FVC, TLC and DLCO ) were statistically significantly correlated with the CT data. Conclusion. During the recovery period in patients after COVID-19, lung structural changes, according to CT scans, persist for at least 3 months. Pulmonary ventilation indicators in most patients normalize during this time, half of the patients retained a decrease in diffusion lung capacity. © 2022, Remedium Group Ltd. All rights reserved.
ABSTRACT
AIM: To evaluate dynamic changes in the lungs, hemostasis system, immune system in different terms after coronavirus pneumonia. MATERIALS AND METHODS: Ventilation-perfusion single-photon emission computed tomography/computed tomography (CT), functional methods of lung investigation, evaluation of hemostasis system, immune status and specific humoral immune response were performed and evaluated in different terms after coronavirus pneumonia. A total of 71 patients were examined according to this protocol. We examined patients with the lesion volume not less than 50% according to chest CT. All patients were divided into 2 groups depending on the distance from the acute stage of coronavirus pneumonia. Group 1 included patients who were examined early (3060 days after hospital discharge), group 2 included patients who were examined later (61180 days after hospital discharge). RESULTS: We obtained gradual regression of pathologically-modified tissue from 67.3% during the inpatient phase to 30.9% during the early period and to 19.7% during the late period of examination, according to CT scan of the chest organs. The same tendency was demonstrated by diffusion capacity of the lungs. Perfusion scintigraphy data showed a decrease in perfusion deficit from 26.012.8% during the early period of examination to 19.46.2% during the late period of examination. On the contrary, ventilatory scintigraphy demonstrates the increase of isotope passage time through the alveolar-capillary membrane over time (from 48.231.3 minutes in the early period to 83.637.2 minutes in the late period). An increase in D-dimer was detected in 24% of patients in the early group. The levels of inflammatory markers, indices of immune status, and specific humoral immune response did not differ in the two described groups. CONCLUSION: The results demonstrate gradual regression of pathological changes caused by coronavirus infection.