Abstract
BACKGROUND: To improve the understanding of acute fibrinous and organizing pneumonia (AFOP), we present one case of AFOP proven by percutaneous lung biopsy along with clinical features, chest imaging and pathology. CASE PRESENTATION: A 50-year-old man was admitted to our department after he was given empiric therapy for community-acquired pneumonia (CAP). The clinical symptoms of the patient were dry cough, chills, night sweats and high fevers. Chest computed tomography (CT) scan showed a high-density shadow in the right lung lobe, similar to lobular pneumonia. The patient was preliminarily diagnosed with community-acquired pneumonia; however, antibacterial treatment was ineffective. To confirm the diagnosis, we performed bronchoscopy and percutaneous lung biopsy; pathology was consistent with AFOP. After he was treated with glucocorticoids, the patient's symptoms were relieved, and the shadow seen on imaging dissipated during the follow-up period. CONCLUSIONS: AFOP is a rare histopathological diagnosis that can be easily misdiagnosed. Clinicians need to consider the possibility of AFOP in the case of invalid antibacterial therapy.