Shahrekord University of Medical Sciences Journal of Shahrekord University of Medical Sciences 2717-0071 27 2 2025 06 29 Pulmonary alveolar proteinosis or coronavirus disease 19 pneumonia: A clinical case study 86 89 10.34172/jsums.998 EN Huriyeh Hashemi https://orcid.org/0000-0003-3412-1997 Amir Mohamad Mozafari https://orcid.org/0000-0001-9212-9597 Nahid Etemadi Toudeshki https://orcid.org/0000-0002-8803-8251 Mihan Pourabdollah Toutkaboni https://orcid.org/0000-0003-2654-9029 Zohre Naderi https://orcid.org/0000-0002-0554-6067 Journal Article 10.34172/jsums.998 2024 06 28 2024 11 09 The COVID-19 pandemic has resulted in a significant number of hospitalizations worldwide, complicating the diagnosis of rare respiratory diseases, such as pulmonary alveolar proteinosis (PAP), which can present with clinical symptoms and radiological findings similar to those of COVID-19. Consequently, accurate diagnosis is crucial. This report describes a case involving a young man with a history of progressive shortness of breath who was initially treated for COVID-19 pneumonia based on high-resolution computed tomography (HRCT) findings. However, following three negative polymerase chain reaction tests from the patient’s throat swab and a lack of clinical improvement despite COVID-19 treatment, he underwent bronchoscopy and bronchoalveolar lavage. The results of these procedures demonstrated PAP. Given that COVID-19 presents with a wide range of manifestations and that HRCT of the lungs is currently the most sensitive diagnostic test for the disease, it is essential to consider the patient’s medical history when diagnosing various pulmonary conditions. More precisely, a thorough assessment of the patient’s history can significantly influence the diagnostic outcome.