Objective: To improve understanding of the clinical, radiological and pathological characteristics of acute fibrinous and organizing pneumonia (AFOP).
Methods: The clinical data of 5 AFOP patients were retrospectively analyzed. AFOP was diagnosed via percutaneous lung biopsy guided by chest computerized tomography (CT) in the Affiliated Drum Tower Hospital of Nanjing University Medical School during March 2011 to June 2012. The clinical, radiological and pathological characteristics of those patients were summarized.
Results: Among the 5 patients, 2 were male and 3 were female, aging 43-61 years. They were all subacute onset. The main clinical manifestations were dyspnea, productive cough, fever and chest pain with hypoxemia via blood gas analysis. Bilateral infiltrates with diffuse and pathy distribution were the predominant features in chest HRCT. The pathological examination revealed slightly widened alveolar septa, 1ymphocyte and plasma cell infiltration and the presence of intra-alveolar fibrin in the form of fibrin "balls" (organization) within the alveolar spaces. No neutrophil, and eosinophil infiltration and hyaline membrane formation were detected, which was different from other well-recognized histologic patterns of acute lung injury, such as diffuse alveolar damage, cryptogenic organizing pneumonia and eosinophilic pneumonia. All patients were treated by corticosteroids and showed significant clinical and radiological improvement.
Conclusions: AFOP has nospecific features, and its diagnosis depends on pathological examination. Treatment with corticosteroids is optimal. However, whether it is a unique interstitial disease needs to be further clinically investigated.