How mutations affecting FOXF1 or its regulatory region cause<unk>  is unknown.<unk> -causing mutations result in abnormal development of lung vasculature and alveoli. In<unk> , the interstitium of alveoli is thickened, with few to no<unk> es located at the alveolar surface to perform gas exchange, and with lower<unk>  density overall. This reduction in<unk> es and their misplacement away from the alveolar surface result in poor oxygenation and retention of carbon dioxide in the blood and high pulmonary blood pressure. There is also evidence of direct connections between pulmonary arteries and systemic vessels, which would deliver deoxygenated blood to the body, also contributing to low blood oxygenation. Another characteristic histologic finding is the presence of a pulmonary vein located next to a pulmonary artery and bronchus in the same bronchovascular bundle. In a normal lung, the pulmonary vein courses with lymphatic vessels in the lung septa.
Alveolar capillary dysplasia
Persistent fetal circulation
Pulmonary alveolar proteinosis
Sepsis
Congenital pulmonary airway malformation
Pneumonia
Pulmonary alveolar microlithiasis
Infant respiratory distress syndrome