Postnatally diagnosed coexisting congenital diaphragmatic hernia with pulmonary sequestration: a report of two cases.

While the associations between pulmonary sequestration (PS) and congenital diaphragmatic hernia (CDH) are known, CDH may be obscured by PS and thus, overlooked on prenatal ultrasonography when coexisting with PS. We present 2 cases of postnatally diagnosed CDH combined with PS. In both cases, PS was prenatally diagnosed as an isolated lung mass, while CDH was confirmed only after birth. Both newborns were sufficiently stable that management was not required immediately after birth. PS may function as an "anatomical barrier" to prevent herniation of the abdominal contents into the chest, thus acting as a "protector" providing normal lung maturation throughout pregnancy. If PS is suspected prenatally, coexisting CDH may be obscured; thus, close prenatal care and counseling of the parents regarding the possibility of CDH are essential. These infants should be delivered at a tertiary center, and imaging should be performed to exclude coexisting CDH.