Bone Mineral Density and Skeletal Manifestations in Patients with Sotos Syndrome - Abstract
Objective: Sotos syndrome is a rare overgrowth disorder. Bone mineral density (BMD) and bone turnover data in patients with Sotos syndrome are scarce. We describe the skeletal status of a paediatric cohort and also pursue the best method to adjust bone mineral density for their tall stature.
Patients and methods: Bone mineral density, bone geometry and laboratory metabolic bone profile were measured in children with diagnosis of Sotos syndrome. Dietary and fracture history, skeletal deformities and presence of pain and comorbidities were recorded.
Results: Eighteen patients aged five to eighteen years old were assessed; twelve (67%) had scoliosis. There was no history of fracture or significant bone pain. However, they all had suboptimal dietary calcium intake. Median, unadjusted for body size BMD Z-scores of lumbar spine and total body less head were normal. However, the Z-scores BMD obtained through height-age (“Ht-A”) and bone age (“BA”) adjustment were lower, especially at the lumbar spine site. Bone markers were within normal values. Regarding bone turnover, a strong negative correlation was found between Z-score BMD TBLH (“BA”) and urinary calcium excretion (UCa/Ucr) (r: -0.731, p<0.05). Finally, a positive correlation was found between Z-score BMD LS (“BA”) and osteocalcin (OC) (r: 0.57, p<0.05).
Conclusion: There was no evidence of osteoporosis in our cohort. Bone mineral density adjustment with bone age reflected our cohort’s bone profile more effectively than with
height-age, as it was correlated significantly with urinary calcium excretion and osteocalcin. Therefore, UCa/Ucr and OC could potentially have a prognostic value for skeletal health.