Hypercalciuria in children with urolithiasis
F. B. Stapleton, H. N. Noe, S. Roy 3rd and G. Jerkins
The pathogenetic roles of idiopathic renal hypercalciuria and absorptive
hypercalciuria in children with urolithiasis have not yet been determined.
Oral calcium loading studies were performed in 21 children with unexplained
calcareous urolithiasis. Thirteen children, aged 20 months to 17 years,
were found to have renal hypercalciuria after an overnight fast (urinary
calcium-urinary creatinine [UCa/UCr] ratio in milligrams, greater than
0.21). Four children were found to have absorptive hypercalciuria. In this
group, fasting UCa/UCr values were normal (SEM, 0.12 +/- 0.02); however,
UCa/UCr values were elevated (SEM, 0.31 +/- 0.01) after the oral calcium
load. Serum parathyroid hormone values were normal in all children with
hypercalciuria. Urinary calcium excretion was normal in four patients.
These data indicate that hypercalciuria may frequently occur in children
with urolithiasis and that detailed metabolic evaluation is warranted in
children with kidney stone disease.
