Growth and bone mineral density in long-lasting idiopathic hypercalciuria

Growth retardation and osteopenia have been reported in some children with idiopathic hypercalciuria (IHC), particularly in those with nephrocalcinosis. The duration of hypercalciuria might be a risk factor for osteopenia. A retrospective longitudinal analysis of statural growth and a cross-sectional evaluation of bone mineral density (BMD) was carried out in 26 IHC children followed for 4-13 years. None of the patients had nephrocalcinosis. Growth, including pubertal growth spurt, was normal in all subjects. BMD Z score less than -1 was recorded in 3 subjects with hyperuricosuria. BMD Z score averaged -0.68+/-0.99 in the 9 subjects with associated hyperuricosuria and 0.21+/-0.64 in the 17 with occasional or no hyperuricosuria (P=0.018). Our analysis shows that children with long-lasting IHC without nephrocalcinosis have normal growth, but those with associated hyperuricosuria may be at risk for osteopenia.