Table 3 Differences in clinical manifestations, radiological characteristics, disease course, treatment and prognosis among patients with ILD, PLC and viral pneumonia

Clinical

Cough, dyspnoea, and worsening hypoxemia and exercise tolerance [14]

Similar with ILD;

Tumour-related symptoms [11]

Similar with ILD;

fever, fatigue, myalgia, sore throat, nasal symptoms and headache [15]

Radiological

Peripheral traction bronchiectasis, mediastinal lymphadenopathy, multiple GGNs, interlobular septal thickening, reticular abnormalities or honeycomb lungs; primarily in the subpleural and basal regions [1]

Interlobular septa thickening (early stage) and nodular thickening (later stage), preservation of lobular architecture; observed reticular, nodular, or reticulonodular patterns with coarse bronchovascular features, as well as hilar/mediastinal adenopathy associated with pleural effusions [9]

Subpleural bronchovascular bundle thickening, multifocal lung consolidation, bronchial air sign, bronchiectasis, paving stone sign and pleural thickening;

observed cord, grid, patchy, nodular, even consolidation, and accompanied by GGNs, pleural effusion and mediastinal lymph adenopathy [16]

Course

Median survival was 36.2–57.7 months with anti-fibrotics [17]

Mean survival was 129days after pulmonary symptoms [11]

Mean hospitalization duration was 17.2–25.9 days [18]

Treatment

Anti-fibrotic therapy

Antitumour therapy

Anti-viral and support therapy

Prognosis

Chronic respiratory failure, lung cancer [17]

Developed fast, approximately 50% patients die within two months of their first respiratory symptoms and three weeks from admission to hospital [11]

Most cured; the mortality rates are 3 − 6.5%, H5N1 (42%) and H7N9 (30%) [15]