Idiopathic Obliterative Bronchiolitis in a Young Woman: A Rare Case of a Transbronchial Lung Biopsy Contributing to the Diagnosis

Idiopathic obliterative bronchiolitis (OB) is a rare disease that usually requires a surgical lung biopsy. A 25-year-old woman with progressive exertional dyspnea for several months showed a severe mixed restrictive and obstructive pattern on spirometry. Chest computed tomography showed a mosaic pattern, and pulmonary ventilation-perfusion scintigraphy showed a matched defect. The bronchoscopic specimens obtained from both the alveolar and bronchiolar regions of the predicted lesion area contributed to the diagnosis of OB. She had no underlying causes of secondary OB, and she was diagnosed with idiopathic OB. Since lung transplantation was indicated, she was referred to a lung transplantation-certified hospital.