Pulmonary agenesis: a predictor of ipsilateral malformations.

Pulmonary agenesis is a rare malformation that can be isolated or associated with other anomalies. We became interested in pulmonary agenesis after evaluation of a child with right pulmonary agenesis, an unlobed left lung, bilateral cleft lip and palate, maxillary and mandibular hypoplasia, bilateral microtia, bilateral radial ray hypoplasia, horseshoe kidney, and complex congenital heart disease. A review of the occurrence of pulmonary agenesis with other congenital anomalies uncovered a striking association with ipsilateral radial ray defects and/or hemifacial microsomia. The presence of bilateral facial or radial ray anomalies was indicative of bilateral pulmonary involvement. A review of the cases of pulmonary agenesis and associated anomalies at the Children's Hospital and Medical Center confirmed the association of pulmonary agenesis and ipsilateral involvement of face and/or radial ray. The association of pulmonary agenesis and ipsilateral malformations may shed light on its pathogenesis. Although the cause of these associated anomalies remains unclear, abnormalities in the development of the aortic arches during embryogenesis is an attractive hypothesis.