Congenital acinar dysplasia: a lethal entity.

Congenital acinar dysplasia is a lethal, developmental lung malformation resulting in neonatal respiratory insufficiency. This entity is characterized by pulmonary hypoplasia and arrest in the pseudoglandular stage of development, resulting in the absence of functional gas exchange. The etiology is unknown, but a relationship with the disruption of the TBX4-FGF10 pathway has been described. There are no definitive antenatal diagnostic tests. It is a diagnosis of exclusion from other diffuse embryologic lung abnormalities with identical clinical presentations that are, however, histopathologically distinct.