Phosphathaushalt und Phosphatbindertherapie

The total body phosphate of approximately 600–700 g is distributed to 80–85% in bones and 15% in soft tissues, blood, ECV and ICV in the form of various inorganic and organic phosphate bonds. As approximately 50% of the phosphate uptake from the intestines is passive and uptake is therefore uncontrolled, in normal healthy kidneys the renal excretion of phosphate is of great significance for phosphate homeostasis within the organism. Loss of this renal regulation in dialysis patients leads to the risk of phosphate accumulation in the body and plays a decisive role in extra-osseal calcification including cardiovascular complications and increased mortality. Because insufficient phosphate can be eliminated by dialysis, intestinal phosphate uptake must be reduced by phosphate binders. The application of various phosphate binders, such as calcium-containing phosphate binders or those containing aluminum, iron and lanthanum as well as calcium and metal-free binders including nicotinic acid and chitosan chewing gum will be discussed.