A case report of acute fibrinous and organizing pneumonia

Rationale: Acute fibrinous and organizing pneumonia (AFOP) is a newly evolving rare non-infectious lung pathology, characterized by intra-alveolar fibrin balls on histology. It is usually difficult to be diagnosed and mistaken for other lung diseases. Patient concerns: In this article, an interesting case about a male patient with a 15-day history of high-grade fever, chills, and no productive cough was presented. He was misdiagnosed as the lung infection early, but exhibited no response to the antibiotic therapy. Diagnosis: The diagnosis of AFOP was determined by the lung biopsy and pathology. Interventions: With the diagnosis of AFOP, all antibiotics were discontinued, and 40mg methylprednisolone daily was given intravenously. Outcomes: The patient responded well to the treatment with steroids. Lessons: AFOP is a rare lung disease characterized by bilateral basilar infiltrates and histological findings of organizing pneumonia and intra-alveolar fibrin in the form of "fibrin balls". Lung biopsy and histopathology were the most important diagnostic methods for the AFOP. Glucocorticoid was an effective drug for the treatment. Subacute patients of AFOP have excellent prognosis with corticosteroids.