Resolution of hydrops fetalis in congenital cystic adenomatoid malformation after prenatal steroid therapy

Background/Purpose: Development of hydrops fetalis in fetuses with congenital cystic adenomatoid malformations (CCAM) is a significant risk factor for fetal or neonatal demise. In rare cases, resolution of CCAM has occurred, presumably owing to lesion maturation or involution. Steroid therapy, utilized for lung maturity, has been postulated to accelerate this process. The natural history of hydropic fetuses with CCAM after receiving steroid therapy is presented. Methods: The authors prospectively followed up with 3 patients who had antenatally diagnosed CCAM and nonimmune hydrops fetalis with predicted mortality. All patients declined or were not candidates for fetal intervention and were treated with standard prenatal betamethasone to increase lung maturity. Results: Three fetuses had CCAM and nonimmune hydrops fetalis diagnosed prenatally. After a course of prenatal steroids during the second trimester, all 3 patients had resolution of their hydrops and were delivered at term without respiratory distress. Conclusions: Nonimmune hydrops fetalis in fetuses with congenital cystic adenomatoid malformation is a harbinger for fetal demise. The resolution of hydrops in these patients after receiving steroid therapy is an interesting and compelling observation. Because the mechanism of this process is speculative, further studies are needed to elucidate the relationship between antenatal steroids and maturation of congenital cystic adenomatoid malformation. J Pediatr Surg 38:508-510.