Interventions for bone disease in children with chronic kidney disease

Chronic kidney disease (CKD) resulting in reduced kidney function and the need for dialysis and kidney transplant is associated with abnormalities in blood calcium and phosphorus levels leading to high levels of the parathyroid hormone (PTH) and to bone disease. This may result in bone deformities, bone pain, fractures and reduced growth rates. Commonly used treatments (Vitamin D compounds and phosphate binders) aim to prevent or correct these outcomes. However these treatments may raise levels of blood calcium, allow calcium and phosphorus deposition in blood vessels and lead to early cardiovascular disease, which is known to be a problem in adults with CKD. This review identified only 15 small RCTs involving 369 children comparing different vitamin D compounds, different routes and frequencies of administration of vitamin D compounds and different phosphate binders. Only five RCTs reported on growth rates and no differences were detected between treatments. Renal bone disease, as assessed by changes in PTH levels, was improved by all vitamin D preparations regardless of preparation used or the route or frequency of administration. Fewer episodes of high blood calcium levels and lower overall serum calcium levels occurred with the non calcium-containing binder, sevelamer, compared with calcium-containing binders. As newer treatments for renal bone disease are developed, comparisons with the current standard therapies will be required in well designed RCTs in children using outcome measures including those of direct clinical relevance to children and their families such as rates of growth, reduction in bone fractures and bone pain and reduction in calcification in blood vessels.