[Acute kidney injury--prevention, risk stratification and biomarkers]

Acute kidney injury influences negatively morbidity and mortality of the critically ill patient and causes increased costs by prolonged length of stay in the intensive care unit. At present the diagnosis and classification of acute kidney injury is derived from the RIFLE and AKIN criteria based on serum creatinine and urine output. The possible pre-, intra- and postrenal causes of acute kidney injury are the starting points of preventive therapy and risk stratification.Because of the unreliability of serum creatinine in critically ill patients the development of new biomarkers raises hope. But none of the promising candidates is used in clinical routine up to now. For evaluation of clinical benefit the results of large prospective multicenter studies have to be awaited.