Prenatal catheter placement for fetal cystic adenomatoid pulmonary malformation: a case report

Fetal congenital cystic adenomatoid malformation is a pulmonary developmental anomaly arising from an overgrowth of the terminal respiratory bronchioles. This is such a rare malformation that it is not always thought of as a diagnostic possibility.

In the present case, after a large pulmonary cyst started deviating the mediastinum and following an increase in amniotic fluid volume in the fetus at 28 weeks of gestation, the placement of a catheter for continuous drainage was performed. Subsequent follow-up with ultrasounds and serial echocardiograms revealed normalization of the position of mediastinum, normal amniotic fluid levels, and the correct position of the catheter. The size of the cyst was decreasing daily, but 8 weeks after fetal invasive procedure, there was concern about the stabilization of its size, with the suspicion of obstruction of the catheter. Cesarean delivery was performed at 38 weeks' gestation. The size of the cyst on the day of C-section was 3.0 x 2.9 x 2.1 cm. At delivery, the infant weighed 3,030 g, with no evidence of respiratory distress, revealing the correct location of catheter. At day 4 after delivery a superior right pulmonary lobe resection was performed.

Large pulmonary cysts may produce deviation of mediastinum and can lead to cardiac tamponade, nonimmune hydrops and pulmonary hypoplasia. Precise prenatal imaging and different fetal therapeutic strategies may allow survival of affected fetuses.