Oxidative stress and 'monocyte reprogramming' in septic patients with acute kidney injury requiring CRRT

Oxidative stress (OS) and monocyte HLA-DR expression are known to be predictive of mortality in sepsis; nevertheless, limited information exists regarding sepsis with acute kidney injury (AKI). The aim of the study was to correlate these markers with outcome in septic patients with AKI requiring continuous renal replacement therapy (CRRT). Advanced oxidation protein products (AOPP) were measured in 32 patients on days 1, 3, 7, 14, 21, and 28. In 14 we assessed the percentage of monocytes expressing HLA-DR (%DR+) and the HLA-DR mean fluorescence intensity (MFI). 20 healthy volunteers, 17 septic patients without AKI and 20 septic AKI patients not treated by CRRT were used for comparison. The mortality rate was 59%. Septic CRRT patients had higher AOPP and lower %DR+ (p < 0.001, both) than healthy controls. They also had higher AOPP than septic patients who did not develop AKI (p < 0.001). No difference was found in AOPP, %DR+ and MFI between survivors and non-survivors (day 1 and subsequent measurements). No correlation was seen between severity scores and OS/HLA-DR. OS and HLA-DR expression are altered in septic patients with AKI undergoing CRRT. However, this study was not able to confirm the usefulness of these markers in predicting survival in this subset of patients.