Sepsis and acute kidney injury as two-way street: values of biomarkers

The brief review, dedicated to Septic Acute Injury (S-AKI) — the syndrome simultaneously corresponding to criteria of sepsis and acute kidney Injury. Sepsis or AKI are diagnosed 30–50 % of critical patients. Sepsis is promoting the developing of AKI and AKI is promoting the development of sepsis. Morbidity and lethality in S-AKI is higher than that is sepsis and in AKI separately. The main mechanisms of the development of: a) AKI in sepsis — the toxic septic blood containing huge amounts of proinflammatory factors damage the renal tubules resulting tubular disfunction; b) sepsis in AKI — uremia is damaging distal organs and functions of immune systems which provoke sepsis development. For early diagnostics of S-AKI in patients admitting in critical care units the simultaneous measurements and monitoring of sepsis and kidney biomarkers are to be made. The problems of such measurements is that AKI decreases the clearance of septic markers and their levels are increasing in noninfectious conditions. From the other hand in septic conditions inflammation can increase the levels of renal markers independently of renal pathologies. In general in sepsis, AKI and in S-AKI the increased levels of sepsis markers reflect simultaneously severity of infectious inflammation and of renal disfunction, and kidney markers reflect simultaneously severity of renal disfunction and of infectious inflammation. The correction of cut-off values of septic markers used for S-AKI diagnostics must be based on the degree of severity of renal disfunction in critical patients.