Major findings - The clinical diagnosis usually requires the presence of 3 or more the following:
(1) macrosomia
(2) hemihyperplasia (hemihypertrophy)
(3) macroglossia, usually present at birth
(4) abdominal wall defect - omphalocele, umbilical hernia, diastasis recti (separation of rectus abdominis muscles)
(5) ear anomalies (anterior linear lobe creases, posterior helical pits)
(6) visceromegaly
(7) renal abnormalities (nephromegaly, duplicate collecting system, medullary sponge kidney, hydronephrosis, renal medullary dysplasia, others)
(8) neonatal hypoglycemia due to hyperinsulinemia
(9) embryonal tumors
Supportive findings:
(1) polyhydramnios
(2) prematurity
(3) enlarged placenta
(4) cardiomegaly with or without cardiomyopathy
(5) structural cardiac defects
(6) nevus flammeus or other hemangiomata
(7) cleft palate
(8) advanced bone age (on radiographs)
(9) midfacial hypoplasia and infraorbital creases
The final diagnosis involves demonstration of a suitable mutation at 11p15.
Potential complications:
(1) persistent hypoglycemia if hyperinsulinemia persists
(2) mental retardation
(3) Wilm's tumor, adrenocortical tumors, hepatoblastomas, rhabdomyosarcoma, neuroblastoma and other embryonal tumors
