Evaluating the association between congenital cystic adenomatoid malformation of the lung and abdominal wall laxity.

We report a male fetus with congenital cystic adenomatoid malformation of the lung, who was treated by laser with resolution of hydrops. Postnatally, the infant had the typical abdominal wall laxity and undescended testes characteristic of prune-belly syndrome. The sonographic diagnosis of cystic adenomatoid malformation was confirmed histologically after postnatal resection. The relationship between cystic adenomatoid malformation and prune-belly syndrome is evaluated through analysis of the present and previously reported cases. We show that there does appear to be a true association between cystic adenomatoid malformation and prune-belly syndrome. We also, however, demonstrate that the traditional explanation (cystic adenomatoid malformation-related hydrops causes ascitic abdominal distension resulting in prune-belly syndrome) is unlikely to be straightforwardly correct.