Secondary organizing pneumonia after coronavirus disease 2019: Two cases

Coronavirus disease 2019 (COVID-19) has been reported to induce persistent symptoms even after an acute phase. However, the pathophysiology and treatment of this condition have been unclear. We report two patients who recovered from COVID-19, but presented persistent respiratory symptoms. Their respiratory conditions deteriorated, and computed tomography showed remaining ground glass opacities and consolidations. The pathological findings of transbronchial lung biopsy corresponded to organizing pneumonia. We diagnosed them with secondary organizing pneumonia after COVID-19. Subsequently, we administered systemic corticosteroids. Their symptoms, oxygenations, radiologic findings, and pulmonary functions rapidly improved after the treatment of corticosteroids. The two cases showed that secondary organizing pneumonia may be a cause of persistent respiratory failure after COVID-19. In this condition, corticosteroids may be effective.