Descripción de un caso: Hallazgos prenatales del síndrome de Silver-Russell

Introduction

Silver-Russell syndrome is a congenital disorder that causes prenatal and postnatal growth restriction, relative macrocephaly, prominent forehead, triangular facies, clinodactyly, body asymmetry, severe feeding difficulties, and low body mass index. The most common underlying mechanisms are hypomethylation of the paternal allele at the imprinting control region 1 (ICR 1) located at 11p15.5 (seen in 50% of patients) and maternal uniparental disomy for chromosome 7 (seen in 7%–10% of patients).

Clinical findings

We present the case of a 29-year-old pregnant woman with low risk for chromosomal abnormalities at the first trimester screening. The 20-week ultrasound shows early intrauterine growth restriction (IUGR). We performed an amniocentesis with normal QF-PCR, foetal karyotype and array-CGH. Intrauterine growth restriction Type I persists at 31 + 4 weeks with estimated foetal weight, abdominal circumference, and femur length below the 1^st centile. The biparietal diameter and head circumference centiles were normal. Prominent forehead, small face, and fifth finger clinodactyly of right hand were detected. At 37 weeks, a boy weighing 1,410 g was born by caesarean section.

Diagnosis, therapeutic intervention, and results

Physical examination revealed a peculiar phenotype suggestive of Silver-Russell syndrome. The genetic study confirmed hypomethylation of ICR1 in the 11p15.5 region. Prenatal ultrasound images are shown.

Conclusions

It is important to diagnose this entity and determine genotype-phenotype correlations in order to provide the best therapeutic options, ensure adequate follow-up, and offer timely family genetic counselling.