Endocrine manifestations in children with Williams–Beuren syndrome

Aim: Endocrine abnormalities in Williams–Beuren syndrome (WBS) include growth retardation, precocious puberty, hypercalcaemia and thyroid disorders. We aimed to characterise these abnormalities in a national cohort of children with WBS. Methods: A retrospective study comprising a national cohort of individuals with WBS in Israel (16 males, 18 females) followed between 2010 and 2016. Results: The age at diagnosis of WBS was 1.4 ± 1.0 years. Height standard deviation score (SDS) at last visit was correlated with the midparental height SDS (r = 0.46 p = 0.007). Yet, participants did not reach their midparental height, with a difference of 1.40 ± 0.85SD (p < 0.001). Short stature below the 3rd percentile was found in 14 participants (41%). Mean insulin-like growth factor 1 SDS was low (−0.61 ± 1.64) and was correlated with the mean height SDS (r = 0.63 p = 0.038). Two participants were diagnosed with growth hormone deficiency, and initiation of growth hormone treatment improved their height velocity. A total of eight participants (23.5%) had mild hypercalcaemia, five girls (14.7%) had precocious puberty and five participants (14.7%) had thyroid abnormalities. Conclusion: Individuals with WBS had a distinct growth pattern consisting of growth restriction at all ages, resulting in final adult height in the low-normal range. Precocious puberty, hypercalcaemia and thyroid abnormalities should be screened for and treated as needed.