Silver-Russell syndrome (SRS) is characterized by intrauterine
(IUGR), postnatal growth restriction, relative macrocephaly and typical
dysmorphic features. Two mechanisms account for 70% of SRS cases:
hypomethylation of 11p15.5 imprinting center region 1 (ICR1) and
maternal uniparental disomy for chromosome 7 (matUPD7). Prenatal
diagnosis is possible only for matUPD7.
We report the antenatal and postnatal data of three unrelated cases
of SRS. Pregnancy was marked by asymmetric IUGR sparing the
head at 22 weeks of gestation (WG) with normal prenatal karyotype.
Cesarean section delivery was induced due to cessation of fetal
growth at 32 WG (case 1) and at 30 WG (case 2) while case 3 was
stillbirth at 27 WG. Postnatal echocardiography detected blocked
supracardiac total anomalous pulmonary venous return (TAPVR) in
case 1 and hypoplastic aortic arch and cardiac TAPVR in case 2. Both
died shortly after birth. Autopsy (refused in case 1) findings were:
multivisceral hypoplasia (case 2), genital and extremity anomalies
(case 3). Hypomethylation of ICR1 11p15.5 was identified in the three
cases and confirmed the clinically suspected diagnosis of SRS.
SRS should be considered in cases with second trimester asymmetric
IUGR sparing the head. Notably, the association of SRS and lethal
cardiopathies is rarely reported. Either they represent two distinct
pathologies or SRS might be underdiagnosed when associated with
lethal cardiopathies. Finally, IUGR, cardiopathies and prematurity led
to death of cases (1 and 2). Should premature delivery in SRS be
avoided to improve prognosis? A reliable prenatal diagnosis for SRS
would prove to be useful.