Alveolar capillary dysplasia (ACD) is a rare, likely congenital, disorder of the lungs (pulmonary system) and especially of the blood system serving the lungs. It is a disorder of the newborn. The normal diffusion process of oxygen from the air sacs to the blood in the lungs and, thence, to the heart, fails to develop properly. The disorder is sometimes called misalignment of the pulmonary veins. Rather than misaligned, the pulmonary vein is malpositioned in a site somewhat different from its normal position.
Infants with the disorder present with the signs of lack of oxygen (hypoxemia) and severely increased pulmonary hypertension.
Since treatment is seldom, if ever, effective, life expectancy of the infant is very, very, short.
