Background: Despite the multiple endocrine, cardiovascular, and gastroenterologic problems of patients with Williams-Beuren Syndrome (WBS), Studies considering metabolism and bone quality in WBS are almost entirely absent from the literature.
Objective and hypotheses: We evaluate bone mineral status and metabolism in a cohort of patients with WBS.
Method: Thirty-one children (15 females, 16 males; mean age 9.61±2.74 years) and ten young adults (six females, four males; mean age 21.4±5.1 years) with WBS were evaluated and compared with two age-, sex-, and body-size-matched healthy control groups. IN WBS and controls we evaluated ionised and total calcium, phosphate, parathyroid hormone (PTH), 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, osteocalcin, bone alkaline phosphatase levels, and urinary deoxypyridinoline concentrations. We also calculated the phalangeal amplitude-dependent speed of sound (AD-SoS) and the bone transmission time (BTT) z-scores. Spearmans (rank) correlation test showed that AD-SoS z-score values were significantly inversely correlated with age (P<0.005). Both BSAP and osteocalcin levels also showed a significant correlation with total calcium values (P<0.005). PTH correlated significantly with ionised calcium (P<0.05) and osteocalcin (P<0.005).
Results: WBS patients showed a significantly reduced AD-SoS z-score (P<0.0001) and BTT z-score (P<0.0001) than the controls. This finding persisted when we divided the sample into paediatric or adult patients. WBS also had significantly higher ionised (P<0.001) and total calcium (P<0.0001) levels as well as higher PTH levels (P<0.0001) compared with the controls. However, WBS children and adolescents had significantly lower serum osteocalcin levels (P<0.001) and urinary deoxypyridinoline concentrations (P<0.0001) than the controls.
Conclusion: WBS subjects exhibit a significant reduction in bone mineral status and impaired bone metabolism; this suggests the need to closely monitor these subjects.
10 - 12 Sep 2016
European Society for Paediatric Endocrinology