Congenital Cystic Adenomatoid Malformation in the Newborn: Two Case Studies and Review of the Literature

Abstract

Congenital cystic adenomatoid malformation (CCAM) is a congenital malformation of the lung that can present on imaging studies as abnormal air, air/fluid-filled cysts, or fluid-filled/solid-appearing cysts. The use of ultrasound in prenatal management has increased the number of cases diagnosed in utero. Early diagnosis is vital in the medical management of CCAM. Outcome varies from hydrops and fetal demise to complete resolution before birth. Many CCAMs diagnosed in utero may decrease in size even if substantial mediastinal shift and lung compression are noted at the time of diagnosis. Once the disorder has been diagnosed, use of serial ultrasound is helpful in providing medical management of the fetus. Two cases of CCAM in the newborn are presented that reflect characteristic clinical features but with distinctly different outcomes, one patient successfully re-sponding to resection and ventilatory support, the other succumbing in the first day of life. The embryology, histology, prenatal and postnatal clinical presentation, and treatment of this malfor-mation are discussed on the basis of a review of the literature. Recent developments in fetal diagnosis and treatment, including fetal surgery, are also presented. We conclude that CCAM should be considered in the differential diagnosis in the presence of respiratory distress and me-diastinal shift. It is especially important for respiratory therapists, nurses, and other members of neonatal transport teams to consider CCAM in the differential diagnosis for any patient who presents with respiratory distress and a chest radiograph showing mediastinal shift. The treatment of choice for this lesion is surgical resection by either segmentectomy or lobectomy. Even in cases of relatively asymptomatic patients with CCAM, surgical resection should be considered because of the reported association of carcinoma and unresected CCAM.