turner syndrome

diagnosis

the most common prenatal ultrasound findings include cystic hygroma, hydrops fetalis, cardiac abnormalities and renal abnormalities, mainly horseshoe kidney. of the fetuses with cystic hygroma detected during the first trimester of pregnancy, about 20% have 45,x. however, in the second trimester of pregnancy, 40% of the cases detected with cystic hygroma have 45,x karyotype. in the newborn period, the major clinical manifestations include dysmorphic facial features with epicanthic folds, ptosis, hypoplasia of the malar areas, prominent ears and retrognathia. the neck is short and webbed with low nuchal hairline, the internipple distance is increased and there is a broad chest. coarctation of the aorta occurs in about 50% of the cases with 45,x and 15% of the cases with other chromosome abnormalities associated with turner syndrome. less common cardiac anomalies include bicuspid aortic valve, vsd, asd and hypoplastic left heart. lymphoedema, usually transient in childhood, occurs in about 80% of the newborns and is mainly noted on the hands and feet. in some, the lymphoedema recurs. renal abnormalities, mainly in the form of horseshoe kidney occur in 20% of the newborns and other renal abnormalities are seen in 20% of the cases. obstructive uropathy with oligohydramnios, potter sequence and cystic dysplasia have also been reported. gonadal dysgenesis or streak gonads are characteristic but usually develop after infancy. skeletal findings include cubitus valgus, short fourth metacarpals, hypoplasia of the cervical vertebrae. without hormone therapy, the bone age remains delayed and osteopenia develops. hypothyroidism, diabetes mellitus, and autoimmune thyroiditis are common. maternal serum screening between 15 and 18 weeks gestation was found positive for down syndrome in turner syndrome associated with hydrops fetalis, with both human chorionic gonadotropin and estriol contributing.