Lung abnormalities in SARS-CoV-2 infection: An analysis of paired computed tomography scans before and after infection.

Abstract Background Studies on the pulmonary consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are impeded by limited access to pre-SARS-CoV-2 examinations. Methods We invited Copenhagen General Population Study participants with a confirmed SARS-CoV-2 PCR test during the first and second COVID-19 wave in Denmark for a repeat chest CT scan. Paired CT scans were independently assessed for interstitial and non-interstitial abnormalities by two trained radiologist. A semiquantitative CT score (ranging from 0-25) was used to quantify the extent of interstitial abnormalities. Results Of 111 SARS-CoV-2 infected individuals, 102 (91.2%) experienced symptoms and 12 (11.2%) were hospitalized. Follow-up examination was performed at median of 5.4 (IQR 4.1; 7.8) months after a positive SARS-CoV-2 PCR-test. Of 67 individuals with paired CT scans, ground glass opacities and reticulation were present in 31 (46.3%) individuals post-SARS-CoV-2 compared to 23 (34.1%) pre-SARS-CoV-2 (mean CT score 3.0 vs 1.3, p = 0.011). Results were similar for non-hospitalized individuals. We did not detect development of bronchiectasis, emphysema or nodules. Conclusions SARS-CoV-2 infection in predominantly non-hospitalized individuals with mild disease was associated with a small increase in only interstitial lung abnormalities.