Renal tract ultrasonography and calcium homeostasis in Williams-Beuren syndrome

Abstract

Renal ultrasound scan, circulating creatinine and calcium, and the urinary calcium excretion rate were investigated in 57 patients with clinically and genetically typical Williams-Beuren syndrome (25 female and 32 male subjects, aged from 1.0 year to 23 years, median 8.5 years) on regular follow up at our institution. Twenty-three unilateral abnormalities were detected in 20 patients: pelvic dilatation ( n=6), renal hypoplasia ( n=5), isolated renal cyst ( n=3), kidney surface irregularity ( n=3), kidney duplication ( n=2), renal agenesis ( n=1), megaureter ( n=1), pelvic kidney dystopia ( n=1), and renal stone ( n=1). Both infantile hypercalcemia and nephrocalcinosis was absent in the 57 patients. Mild hypercalcemia was noted in 1 and mild hypercalciuria in 2 patients after the 1st year of life. In conclusion, the study indicates the frequent occurrence of intrinsic renal tract abnormalities detected by ultrasonography in Williams-Beuren syndrome. However, the study does not confirm the importance given in the past to the occurrence of hypercalcemia and hypercalciuria.

Clinical follow‐up of young adults affected by Williams syndrome: Experience of 45 Italian patients

“…Eleven of 45 (24%) experienced urinary tract structural abnormalities at abdominal ultrasound examination. This percentage is consistent with previously reported studies [Pankau et al, 1996;Sforzini et al, 2002].…”

Severe Infantile Hypercalcemia Associated With Williams Syndrome Successfully Treated With Intravenously Administered Pamidronate

“…35 The authors concluded that, in WS, hypercalcemia is not frequent and hypercalciuria is rare after the first 1 year of life; they speculated that the issue of disturbed calcium homeostasis in WS has been overemphasized in the past. Our report challenges these views, given the severity of hypercalcemia for patients 1 and 2, nephrocalcinosis for patients 2 and 3, and the age of onset and recurrence of hypercalcemia for patient 3.…”

Williams syndrome with severe hypercalcaemia

“…The moderate–severe forms most often occur within the first year of life and resolve by age 4 12 13. Nephrocalcinosis is detected in approximately 5%–10% of patients undergoing renal ultrasonography 8. Hypercalcaemia causes dehydration by directly affecting renal distal tubular function, impairing concentrating ability leading to polyuria.…”