COVID-19 and severe pulmonary alveolar proteinosis (PAP): A case report.

Background: Pulmonary alveolar proteinosis (PAP) is a rare lung disease that mainly presents with dyspnea. PAP diagnosis can be easily missed in the background of a coronavirus disease 2019 (COVID-19) infection, due to the similarity of their presentation and radiological findings. We present a case report of a post-COVID-19 patient, who later developed severe PAP.