A Rare Case of Pulmonary Ossification Findings That Rapidly Progressed and Improved During the Course of COVID ‐19 Pneumonia

ABSTRACT An 88‐year‐old man with a history of myocardial infarction, non‐valvular atrial fibrillation and hypothyroidism was admitted to our hospital with a diagnosis of coronavirus disease. On admission, he had hypoxemia, with peripheral blood oxygen saturation at 95% on 5 L of oxygen via face mask ventilation. Chest computed tomography (CT) showed bronchial wall thickening and emphysema in both lungs, ground‐glass opacities and high‐attenuation areas in the bilateral lower lungs. After hospitalization and treatment, hypoxemia improved; however, chest CT showed marked progression of the high‐attenuation areas, suggestive of pulmonary ossification (PO) in both lower lungs. The patient was transferred to a rehabilitation hospital; however, hypoxemia had improved at the time of discharge and chest CT showed marked improvement in the findings suggestive of PO.