Alveolar Capillary Dysplasia (ACD) is a rare, often lethal, congenital lung developmental disorder marked by an abnormality in the alignment of pulmonary veins and deficient capillary development.
You have millions of air sacs (alveoli) in your lungs. These air sacs move oxygen into your blood. Alveolar walls contain surfactant. This is a substance made of fats, proteins, and other substances.