Multidisciplinary management of a large microcystic congenital pulmonary airway malformation: case report and literature review.

INTRODUCTION: Congenital pulmonary airway malformations (CPAMs) are rare sporadic lesions frequently associated with poor fetal prognosis. Type 3 CPAMs are characterized by small hyperechogenic cysts (<5 mm). Hydrops often develops secondarily, and the fetal survival rate is approximately 5% in this setting.

CASE PRESENTATION: We present a case of a large type 3 CPAM complicated by fetal hydrops. The lesion was detected at 19 gestational weeks (GW) and confirmed by fetal MRI at 29 GW. At 22 GW, a course of maternal steroids was given as a possible treatment of type 3 CPAM. Peritoneal-amniotic shunt was placed twice to reduce fetal ascites, with unsatisfactory results. Similarly, polyhydramnios was relieved by two amnioreductions, but redeveloped soon after. A baby girl was delivered spontaneously at 33 GW and received a two-stage partial lobectomy in the first three months of life. Desaturations necessitated challenging invasive oscillatory ventilation between stages. Her outcome is unexpectedly positive and she may expect a good quality of life. She now approaches one year of age, with near-to-normal growth and developmental milestones.

DISCUSSION: Type 3 CPAMs complicated by fetal hydrops are associated with high perinatal mortality. While open fetal surgery remains a viable option in select specialist centers, antenatal interventions are typically ineffective. The survival of this infant can be attributed to prenatal management and early postnatal surgical intervention. The lack of guidelines for ventilation in this setting was a significant challenge for neonatal intensivists. Multidisciplinary vigilance and collaboration with frequent specialist follow ups were the key to success for both mother and child.