[The past, the present and the future of renal replacement therapy]

Abstract

The observation that renal failure leads to 'uraemia' through retention of solutes that would otherwise be excreted by healthy kidneys, has been formulated as early as the first half of 19th century. The discovery of osmosis and a colloid membrane facilitated the first testing ofdialysis, originally in animals and in the first quarter of 20th century also in humans. In the mid 1940s, dialysis became the method of choice for the treatment of acute renal failure. At the beginning of 1960s, the development of long-term venous access made programmes of chronic haemodialysis possible in many countries. These achievements, together with kidney transplantation, saved or significantly extended life of millions of patients with chronic renal failure. The last 50 years saw a dramatic increase in the number of chronically dialyzed patients; the safety and efficacy of haemodialysis methods improved and effective treatments have been introduced of a number of complications associated with chronic renal failure (e.g. hypertension, anaemia or bone disease). Despite this, mortality of, particularly older chronically dialyzed patients, is very high and their quality of life sometimes low. High cardiovascular mortality, frequently due to chronic heart failure and sudden death (unlike ischemic heart disease in healthy population), is a dominating problem. However, it is difficult to reduce the high cardiovascular morbidity and mortality of haemodialyzed patients. Patient prognosis might probably be improved by more frequent use of convective methods of blood purification and frequent haemodialysis as well as effective management ofdyslipidemia. Nevertheless, early diagnosis of patients with chronic renal insufficiency and early management of all general as well as renal failure-specific risk factors in patients with mild to moderate chronic renal insufficiency is essential if the prognosis ofhaemodialyzed patients is to be improved. Future developments of renal replacement therapies are difficult to predict. The treatment should be individualized; early transplantation, peritoneal or home (frequent) haemodialysis should be performed in younger patients and conservative treatment, in addition to chronic haemodialysis, should be used in older patients. Miniaturization as one of the potential future trends could facilitate the use of portable artificial kidney. Artificial membranes coated with proximal tubule cells and ex vivo kidney cultivation represent another interesting perspective.