Asymmetrical Interstitial Lung Disease Suggested to Be Due to Hypoplasia of the Unilateral Pulmonary Artery: A Case Report with a 20-year Follow-up

We herein report a case of asymmetrical interstitial lung disease (ILD) that remained almost completely asymmetrical over time on chest computed tomography (CT). An open lung biopsy from the right lung showed severe pleural adhesion, obstruction of the pulmonary artery, and dilated systemic arteries in addition to the usual interstitial pneumonia pattern. Three-dimensional CT angiography showed partial defects of pulmonary arteries on the affected side. After excluding other known causes of ILD and gastroesophageal reflux, we suspected that decreased pulmonary artery perfusion in the present case may have been responsible for the observed asymmetrical unilateral fibrosis.