Insidious pulmonary fibrosis occurring at the hypoperfusion area in a patient with chronic pulmonary thromboembolism

A 69-year-old woman who had been diagnosed with chronic pulmonary thromboembolism (CPTE) developed ground glass opacities in the right lung where perfusion scintigraphy showed defects of the bloodstream. Bronchoalveolar lavage fluid (BALF) showed that some macrophages had phagocytosed hemosiderin. Video-assisted thoracoscopic surgical biopsy revealed lung fibrosis, narrowing of the pulmonary artery and organization of many cholesterol granulomas. We hypothesized that hyperperfusion of the bronchial artery, which occurred to compensate for hypoperfusion of the pulmonary artery, induced alveolar hemorrhage following thrombolytic and anticoagulation treatments, and that the degraded products from blood cells induced the formation of lung fibrosis and cholesterol granulomas.