Pulmonary fibrosis in critical ill patients recovered from COVID-19 pneumonia: Preliminary experience

To investigate chest computed tomography (CT) findings associated with severe COVID-19 pneumonia in the early recovery period.

We retrospectively analyzed the cases of patients diagnosed with severe COVID-19 pneumonia at a single center between January 12, 2020, and March 16, 2020. The twelve ICU patients studied had been diagnosed SARS-CoV-2 (COVID-19) nucleic acid positive. Patient clinical symptoms were relieved or disappeared, and basic clinical information and laboratory test results were collected. The study focused on the most recent CT imaging characteristics.

The average age of the 12 patients was 58.8 ± 16.2 years. The most prevalent symptoms were fever (100%), dyspnea (100%), and cough (83.3%). All patients experienced acute respiratory distress syndrome (ARDS), of which 9 were moderate to severe. Six patients used noninvasive ventilators, and 4 patients used mechanical ventilation. One patient was treated with extracorporeal membrane oxygenation (ECMO). The lymphocyte count decreased to 0.67 ± 0.3 (× 10 ⁹/L). The average day from illness onset to the last follow-up CT was 56.1 ± 7.7 d. The CT results showed a decrease in ground glass opacities (GGO), whereas fibrosis gradually increased. The common CT features included GGO (10/12, 83.3%), subpleural line (10/12, 83.3%), fibrous stripes (12/12, 100%), and traction bronchiectasis (10/12, 83.3%). Eight patients (66.7%) showed predominant reticulation and interlobular thickening. Four patients (33.3%) showed predominant GGO. Lung segments involved were 174/216 (80.6%).

Fibrous stripes and GGO are common CT signs in critically ill patients with COVID-19 pneumonia in the early recovery period. Signs of pulmonary fibrosis in survivors should be carefully monitored.