Spontaneous Resolution of Nonimmune Hydrops in a Fetus with a Cystic Adenomatoid Malformation

Congenital cystic adenomatoid malformation (CCAM) is a rare pulmonary anomaly. It is a hamartomatous lesion characterized by a cessation of normal bronchiolar maturation, resulting in overgrowth of the terminal bronchioles. There is no preference for sex or location, and usually the lesion is confined to a single lobe. CCAMs have been classified into three subtypes according to the presence of and size of the cysts. Type I lesions have large cysts (2 to 10 cm in diameter), type II have smaller cysts (<1 cm in diameter), and type III is noncystic.¹ There have been several reports of diminution in size of these lesions^2,3 and complete regression.^4,5 However, in those cases fetal hydrops was absent. In the presence of nonimmune hydrops, fetal prognosis is extremely poor without any intervention.⁶ There are only two case reports describing fetal survival without intervention when nonimmune hydrops is present.^7,8 We present a case of survival of a fetus with CCAM and nonimmune hydrops diagnosed at 24 weeks' gestation. (J Perinatol 1998;18:308-10.).