Post-COVID-19 sequelae of the respiratory system. A single-centre experience reporting the compromise of the airway, alveolar and vascular components

The long-term sequelae of COVID-19 have now become more common and appreciable. The SARS-CoV-2 virus can cause a variety of infectious and non-infectious pulmonary complications. The purpose of this study is to raise awareness about post-COVID-19 pulmonary sequelae, both infectious and non-infectious, in this geographical area. A retrospective study was conducted from July 1^st 2020 to December 20^th 2020. A total of 1200 patients were evaluated, with 83 suffering from post-COVID-19 pulmonary complications. The patients' mean age was 62 years (IQR 55-69), with 63 (75.9%) being male. The most common co-morbid illnesses were hypertension (49, 59%) and diabetes (45, 54.2%). The majority of them (37, 44.6%) had severe COVID-19, followed by critical COVID-19 (33, 39.8%). There was no statistically significant difference in recurrence of respiratory symptoms or duration of current illness between non-severe, severe, and critical COVID-19 patients. Non-infectious complications were observed in the majority of patients (n=76, 91.5%), including organizing pneumonia/ground glass opacities in 71 (88%) patients, fibrosis in 44 (55%), pulmonary embolism in 10 (12.5%), pneumomediastinum in 6 (7.4%) and pneumothorax in 7 (8.6%). Infective complications (25, 30.1%) included aspergillus infection in 10 (12.0%) and bacterial infection in 5 (8.47%), with more gram-negative infections and one patient developing Mycobacterium tuberculosis. Post COVID-19 mortality was 11 (13.3%). The long-term pulmonary sequelae of COVID-19 are not rare. Cryptogenic organizing pneumonia, ground glass opacities, and fibrosis were common post-COVID-19 sequelae in our patients. This necessitates frequent close monitoring of these patients in order to initiate early appropriate management and prevent further morbidity and eventual mortality.