Idiopathic hypercalciuria in childhood

In children, urinary calcium excretion of more than 0,1 mmol/kg/day in the absence of known causes of hypercalciuria is defined as idiopathic hypercalciuria (IHC). Dietary factors such as intake of calcium, protein, phosphate and sodium must considered since they influence the excretion of calcium. IHC does not cause acute symptoms, but under certain conditions it may result in abdominal pain, dysuria, he maturia, nephrolithiasis, nephrocalcinosis or feeding problems. Up to now the exact pathogenesis is unknown. Traditional and new concepts of pathogenesis are discussed. The risk of the development of complications cannot be predicted at the moment. Complications in IHC necessitate treatment to achieve normocalciuria. In many cases dietary management (normal calcium and balanced sodium and protein intake) is sufficient. Hydrochlorothiazide and inhibitors of prostaglandin synthesis may be suitable drugs for reducing hypercalciuria.