Uremia Retention Molecules and Clinical Outcomes

Chronic kidney disease is characterized by the accumulation of organic compounds in the bloodstream that may exert a variety of toxic effects in the body. These compounds, collectively known as uremic toxins, may be classified according to their physicochemical properties as free water-soluble low molecular weight molecules, middle molecules or protein-bound uremic toxins. Most of these retention molecules, due to either their size and/or binding to protein, constitute a complex therapeutic challenge to the nephrologist, particularly in end-stage renal disease, because of their limited removal by conventional dialysis therapies. Therefore, we review in this article the current clinical evidences that have supported the important role of uremic toxins in uremia by contributing to the adverse outcomes related to chronic kidney disease, such as increased mortality and cardiovascular events, as well as renal impairment progression that cannot be solely explained by traditional risk factors. These observations have ultimately contributed to testing new therapeutic targets, such as the gut, and the development of modern dialysis strategies to manage chronic kidney disease patients.