Practical pediatric nephrology Hematuria associated with hypercalciuria and hyperuricosuria: a practical approach

Hematuria is one of the most common urinary abnormalities found in children. When hypercalciuria was identified as a potential etiology of painless hematuria, many questions arose concerning the general importance of this observation. Subsequently, increased uric acid excre- tion also has been purported to cause hematuria in children. This review traces the history of these observations and describes the clinical characteristics of the clinical syn- drome of hematuria associated with hypercalciuria and hyperuricosuria. Diagnostic criteria of excessive urinary excretion of calcium and uric acid are reviewed; differences in urinary calcium and uric acid excretion between infants and older children are emphasized. Aside from urolithiasis, few long-term consequences from hypercalciuria or hy- pemricosuria have been identified, although some debate exists concerning the effect of chronic hypercalciuria upon bone mineralization.