Context: There is little information on the long-term natural history of Silver-Russell syndrome (SRS).
Objective: To describe the phenotypes and metabolic status in adults with SRS.
Design: Clinical and metabolic evaluations in adults with a molecular diagnosis of SRS.
Participants: Seven patients (aged 18 to 46 years; mean age, 26.9 years) were studied. Two had chromosome 7 maternal uniparental disomy, three had 11p15 loss of methylation, and two had 11p15 duplication.
Setting: Single tertiary university center.
Main outcome measures: Netchine-Harbison (NH) clinical score, oral glucose tolerance test, lipid profiles, bone mineral density (BMD; lumbar spine at L1 to L4 and total body), lean body mass (LBM), absolute fat mass (kg), fat mass percentage, fat mass index (FMI), and trunk/limb fat ratio were evaluated.
Results: The NH score declined in all but two patients during adulthood, and all patients but one displayed relative macrocephaly. Two patients were underweight, four patients had a normal body mass index, and one was obese. Two patients had glucose intolerance and hyperinsulinemia; two showed a high total cholesterol level with low high-density lipoprotein (HDL) cholesterol levels. BMD was within the normal range, whereas a high fat mass percentage, FMI, and trunk/limb fat ratio and a low LBM were found. The trunk/limb fat ratio showed an inverse relation with HDL cholesterol levels.
Conclusions: The diagnosis of SRS seems to be reliable in adults, although some clinical signs become less pronounced with age. Glucose, lipids, and body composition should be monitored over time.