Urinary calcium excretion was assessed in 83 consecutive children with gross or microscopic hematuria in whom the presence of proteinuria or urinary-tract infection had been excluded. Twenty-three children had hypercalciuria. Clinical features that were more commonly associated with hypercalciuria included gross hematuria and a family history of urolithiasis. No clinical or pathological basis for the hematuria was determined in 22 of the 23 children with hypercalciuria or in 38 of the 60 children with normal calcium excretion. Urolithiasis developed in two children with hypercalciuria during the period of study. Oral calcium-loading tests were performed in all 23 children with hypercalciuria. Absorptive hypercalciuria was demonstrated in 10 children, whereas 13 had renal (fasting) hypercalciuria. Hematuria resolved during anticalciuric therapy in 20 of the 23 patients with hypercalciuria. We conclude that determination of urinary calcium excretion is warranted in the routine evaluation of children with hematuria.

Our clinical experience with 47 pediatric patients with stones is reviewed. Surgical therapy was standard with successful stone manipulation in 12 of 13 patients. In 91 per cent of our patients factors causing or predisposing to stone disease were discovered. A thorough metabolic evaluation, including an oral calcium loading test in 20 children, proved to be helpful. A new patient subgroup relating unexplained hematuria to eventual stone formation is described. Our protocol for metabolic evaluation and recommendations for treatment based on the results of such an evaluation are given. We have found the metabolic evaluation of the child with stones meaningful and particularly helpful in planning subsequent therapy for these patients.