18 months computed tomography follow-up after Covid-19 interstitial pneumonia.

Abstract

Background: Our aim is to evaluate the possible persistence of lung parenchyma alterations, in patients who have recovered from Covid-19.Design and methods: We enrolled a cohort of 115 patients affected by Covid-19, who performed a chest CT scan in the Emergency Department and a chest CT 18 months after hospital discharge. We performed a comparison between chest CT scan 18 months after discharge and spirometric data of patients enrolled. We obtained quantitative scores related to well-aerated parenchyma, interstitial lung disease and parenchymal consolidation. A radiologist recorded the characteristics indicated by the Fleischner Society and “fibrotic like” changes, expressed through a CT severity score ranging from 0 (no involvement) to 25 (maximum involvement).Results: 115 patients (78 men, 37 women; mean age 60.15 years old ±12.52). On quantitative analysis, after 18 months, the volume of normal ventilated parenchyma was significantly increased (16.34 points on average ±14.54, p<0.0001). Groundglass opacities and consolidation values tend to decrease (-9.80 and -6.67 points, p<0.0001). On semiquantitative analysis, pneumonia extension, reactive lymph nodes and crazy paving reached statistical significance (p<0.0001). The severity score decreased by 2.77 points on average (SD 4.96; p<0.0001). There were not statistically significant changes on “fibrotic-like” changes correlated with level of treatment and there was not a statistically significant correlation between CT lung score and spirometric results obtained 18 months after discharge.Conclusions: Patients recovered from Covid-19 seem to have an improvement of ventilated parenchyma and “fibrotic-like” alterations. The level of treatment does not appear to influence fibrotic changes. Significance for public health After more than a year from first SARS-CoV-2 infection cases in Europe, alongside the always current problems of diagnosis and clinical management, a new criticism is emerging: the possible long-term outcomes that Covid-19 patients may have. To try to answer at least in part this question, in agreement with the pulmonologists of our center, we decided to select a group of patients who have overcome Covid-19, with heterogeneous levels of intensity of care, and to perform a radiological and clinical 18 months follow-up. In this paper we made a comparison between the chest CT performed at the onset of the disease and the CT performed after 18 months, evaluating the evolution of the parenchymal alterations. We hope that the results obtained in this study can provide useful information in the future follow-up of patients affected by Covid-19, a central issue of public health in the coming years in many areas of the world.