RT Journal Article
SR Electronic
T1 Urinary Excretion of Calcium Following an Oral Calcium Loading Test in Healthy Children
JF Pediatrics
JO Pediatrics
FD American Academy of Pediatrics
SP 594
OP 597
VO 69
IS 5
A1 Stapleton, F. Bruder
A1 Noe, H. Norman
A1 Jerkins, Gerald
A1 Roy, Shane
YR 1982
UL http://pediatrics.aappublications.org/content/69/5/594.abstract
AB The ratio of urinary calcium (UCa)/urinary creatinine (UCr) concentrations (mg/mg) during calcium loading has been used to diagnose hypercalciuric states in adults. The UCa/UCr ratios have been examined before and after an oral dose of calcium in 48 healthy children following five days of abstinence from dietary milk products. No differences in UCa/UCr ratios were observed between sexes, races, or age groups. UCa/UCr ratio before the calcium dose was 0.09 ± 0.12 (mean ± 2 SD) and increased to 0.12 ± 0.15 in urine samples collected for four hours after the calcium load. A direct relationship between UCa/UCr ratio and urinary sodium (UNa)/UCr ratio was observed (r = .57, P < .01). In six children, calcium loading studies were repeated without prior restriction of dietary calcium. Dietary calcium intake before the calcium loading had little effect upon UCa/UCr ratio before the calcium dose in these six children (0.068 vs 0.08); however, UCa/UCr values after the calcium load were significantly lower (0.08 vs 0.15) when no dietary calcium restriction preceded the calcium-loading study. These data may allow characterization of renal hypercalciuria and gastrointestinal hyperabsorption of calcium in children with urolithiasis.