A 34-year-old man who did not use tobacco complained of hemoptysis with a small volume, severe dry cough, and low-grade fever for 5 months. He denied dyspnea, chest pain, night sweats, or weight loss. Chest CT scanning showed nodules with a cavity in the lower left lung. Pathogenic tests of BAL fluid were negative. Initially, he was diagnosed with pneumonia and received antibiotics. After a week, his symptoms resolved, and he was discharged from the hospital. Two months later, the patient presented again for the onset of dry cough and hemoptysis. Despite symptomatic treatment, his symptoms and chest CT scans had no improvement. Thereby, he was referred to our institution. He was prone to spontaneous bruising since childhood with a family history of spontaneous cerebral aneurysm. At 21 years of age, the patient underwent an appendectomy because of a suspected perforation. Also, he experienced cerebral hemorrhage 3 years earlier.

A 51-year-old man presented with chest tightness, exertional dyspnea, and occasional chest pain for 2 years. The patient visited his local hospital initially, and CT scan revealed a ground glass opacity (GGO) located in the right upper lobe (Fig 1A). He was diagnosed as having pulmonary infection and treated with levofloxacin for 12 days. A repeated chest CT scan 14 days later demonstrated a progressed solid nodule with surrounding ground glass opacity (Fig 1B). With a suspicion of carcinoma in situ, right upper lobectomy was performed via video-assisted thoracoscopic surgery at the local hospital. However, the histologic examination did not show any evidence of malignancy, and the symptoms persisted. Fourteen months later, his dyspnea worsened with extremely low exercise tolerance. The patient denied other symptoms (eg, rash, fever, joint pain, aphthous stomatitis, genital ulceration, other symptoms of arteritis). His appetite was decreased but without significant weight loss. He did not smoke and had a history of fully recovered cerebral infarction 9 months ago. There was no family history of respiratory diseases. After 4 months, a CT pulmonary angiography scan revealed filling defects at the left pulmonary artery and left inferior pulmonary artery (Fig 2A). A vascular narrowing was detected at the left superior pulmonary artery. Accompanied with an increased D-dimer level (> 10 mg/L; normal range, 0-0.5 mg/L), a diagnosis of pulmonary embolism was made. The patient was treated with warfarin, and his symptom of dyspnea was partially relieved. He came to our hospital for further treatment 4 months later.