Post-COVID Interstitial Lung Disease: How do We Deal with This New Entity?

• Published in: Balkan medical journal Vol. 41; no. 5; pp. 377 - 386
• Main Authors: Yüksel, Aycan, Karadoğan, Dilek, Hürsoy, Nur, Telatar, Tahsin Gökhan, Köse Kabil, Neslihan, Marım, Feride, Kaya, İlknur, Er, Aslıhan Banu, Erçelik, Merve, Polat Yuluğ, Demet, Yumrukuz Şenel, Merve, İlgar, Ceren, Gültekin, Ökkeş, Çakmakcı Karakaya, Selin, Yılmaz Kara, Bilge, Özçelik, Neslihan, Selimoğlu, İnci, Uyar Er, Kübra, Kotan, Abdurrahman, Veysel Keskin, Hasan, Akgün, Metin
• Format: Journal Article
• Language: English
• Published: Turkey Galenos Yayinevi Tic. Ltd 01.09.2024; Galenos Publishing House
• Subjects: Aged; Care and treatment; Coronaviruses; COVID-19 - complications; COVID-19 - physiopathology; Cross-Sectional Studies; CT imaging; Diagnosis; Dyspnea - etiology; Dyspnea - physiopathology; Female; Humans; Lung diseases; Lung diseases, Interstitial; Lung Diseases, Interstitial - etiology; Lung Diseases, Interstitial - physiopathology; Male; Medical research; Medicine, Experimental; Middle Aged; Post-Acute COVID-19 Syndrome; Pulmonary function tests; Respiratory Function Tests - methods; Risk Factors; SARS-CoV-2; Tomography, X-Ray Computed - methods; Turkey
• ISSN: 2146-3123; 2146-3131; 2146-3131
• DOI: 10.4274/balkanmedj.galenos.2024.2024-3-82

In the postacute phase of coronavirus disease-2019 (COVID-19), survivors may have persistent symptoms, lung function abnormalities, and sequelae lesions on thoracic computed tomography (CT). This new entity has been defined as post-COVID interstitial lung disease (ILD) or residual disease. To evaluate the characteristics, risk factors and clinical significance of post-COVID ILD. Multicenter cross-sectional analysis of data from a randomized clinical study. In this study, patients with persistent respiratory symptoms 3 months after recovery from COVID-19 were evaluated by two pulmonologists and a radiologist. post-COVID ILD was defined as the presence of respiratory symptoms, hypoxemia, restrictive defect on lung function tests, and interstitial changes on follow-up high-resolution computed tomography (HRCT). At the three-month follow-up, 375 patients with post-COVID-19 syndrome were evaluated, and 262 patients were found to have post-COVID ILD. The most prevalent complaints were dyspnea (n = 238, 90.8%), exercise intolerance (n = 166, 63.4%), fatigue (n = 142, 54.2%), and cough (n = 136, 52%). The mean Medical Research Council dyspnea score was 2.1 ± 0.9, oxygen saturation was 92.2 ± 5.9%, and 6-minute walking distance was 360 ± 140 meters. The mean diffusing capacity of the lung for carbon monoxide was 58 ± 21, and the forced vital capacity was 70% ± 19%. Ground glass opacities and fibrotic bands were the most common findings on thoracic HRCT. Fibrosis-like lesions such as interlobular septal thickening and traction bronchiectasis were observed in 38.3% and 27.9% of the patients, respectively. No honeycomb cysts were observed. Active smoking [odds ratio (OR), 1.96; 95% confidence interval (CI), 1.44-2.67), intensive care unit admission during the acute phase (OR, 1.46; 95% CI, 1.1-1.95), need for high-flow nasal oxygen (OR, 1.55; 95% CI, 1.42-1.9) or non-invasive ventilation (OR, 1.31; 95% CI, 0.8-2.07), and elevated serum lactate dehydrogenase levels (OR, 1.23; 95% CI 1.18-1.28) were associated with the development of post-COVID ILD. At the 6-month follow-up, the respiratory symptoms and pulmonary functions had improved spontaneously without any specific treatment in 35 patients (13.4%). The radiological interstitial lesions had spontaneously regressed in 54 patients (20.6%). The co-existence of respiratory symptoms, radiological parenchymal lesions, and pulmonary functional abnormalities which suggest a restrictive ventilatory defect should be defined as post-COVID-19 ILD. However, the term “fibrosis” should be used carefully. Active smoking, severe COVID-19, and elevated lactate dehydrogenase level are the main risk factors of this condition. These post-COVID functional and radiological changes could disappear over time in 20% of the patients.