Coronavirus disease 2019 (COVID-19) commonly produces non-specific respiratory symptoms and chest computed tomography (CT) abnormalities that can overlap with non-infectious disorders. We describe three patients whose clinical and radiological presentations initially suggested COVID-19 pneumonia but whose severe acute respiratory syndrome coronavirus 2 testing was negative. A 53-year-old woman with rheumatoid arthritis had multifocal bilateral consolidation and ground-glass change; bronchoscopic cryo biopsy showed organising pneumonia, and the abnormalities resolved with prednisolone. A 19-year-old man had bilateral ground-glass opacities, marked peripheral eosinophilia, and bronchoscopic lavage with 50% eosinophils, supporting idiopathic eosinophilic pneumonia; he improved after prednisolone. A 68-year-old man with fever and haemoptysis had bilateral nodular and ground-glass changes; echocardiography revealed severe mitral valve prolapse with chordal rupture and significant mitral regurgitation. These cases demonstrate that COVID-19-like imaging is not specific and that persistent test negativity should prompt careful evaluation for alternative inflammatory, eosinophilic, and cardiogenic causes.

Keywords: COVID-19 Pneumonia; COVID-19 Mimics; Pulmonary Eosinophilia; Cryptogenic Organising Pneumonia; Mitral Valve Regurgitation; Cryo Lung Biopsy

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