Residual Lung Abnormalities in Survivors of Severe or Critical COVID-19 at One-Year Follow-Up Computed Tomography: A Narrative Review Comparing the European and East Asian Experiences

Abstract

The literature reports that there was a significant difference in the medical impact of the coronavirus disease (COVID-19) pandemic between European and East Asian countries; specifically, the mortality rate of COVID-19 in Europe was significantly higher than that in East Asia. Considering such a difference, our narrative review aimed to compare the prevalence and characteristics of residual lung abnormalities at one-year follow-up computed tomography (CT) after severe or critical COVID-19 in survivors of European and East Asian countries. A literature search was performed to identify articles focusing on the prevalence and characteristics of CT lung abnormalities in survivors of severe or critical COVID-19. Database analysis identified 16 research articles, 9 from Europe and 7 from East Asia (all from China). Our analysis found a higher prevalence of CT lung abnormalities in European than in Chinese studies (82% vs. 52%). While the most prevalent lung abnormalities in Chinese studies were ground-glass opacities (35%), the most prevalent lung abnormalities in European studies were linear (59%) and reticular opacities (55%), followed by bronchiectasis (46%). Although our findings required confirmation, the higher prevalence and severity of lung abnormalities in European than in Chinese survivors of COVID-19 may reflect a greater architectural distortion due to a more severe lung damage.

Keywords: COVID-19; SARS-CoV-2; follow-up studies; multidetector computed tomography.

Figure 1

Cropped axial thin-section computed tomography (CT) images with lung window setting show some examples of long-term chest CT findings in survivors of coronavirus disease (COVID-19): (a) ground-glass and subpleural curvilinear opacities; (b) reticular opacities with architectural distortion and bronchiectasis; (c) reticular opacities with architectural distortion and traction bronchiectasis.

Figure 2

Prevalence of different types of CT lung abnormalities in survivors of severe or critical COVID-19 at one-year follow-up (European studies). ANY, any residual lung abnormalities; GGO, ground-glass opacities; RO, reticular opacities; LO, linear opacities; C, consolidation; B, bronchiectasis; H, honeycombing.

Figure 3

Prevalence of different types of CT lung abnormalities in survivors of severe or critical COVID-19 at one-year follow-up (Chinese studies). ANY, any residual lung abnormalities; GGO, ground-glass opacities; RO, reticular opacities; LO, linear opacities; C, consolidation; B, bronchiectasis; H, honeycombing.