The role of advanced oxidation protein products in intensive care unit patients with acute kidney injury

Introduction Oxidative stress (OS) is an Imbalance between the production of oxidizing chemical species and the antioxidant defense It is known that OS increases in critically ill patients with acute kidney injury (AKI) Measurement of advanced oxidation protein products (AOPPs) has been found to be a simple tool for monitoring OS Aims The aims of this study were to evaluate OS in intensive care unit (ICU) patients by AOPP levels and compare its levels between patients with and without AKI, we also wanted to assess the ability of AOPP to predict the development of AKI in this population Patients, Material, and Methods We performed a prospective cohort study to compare AOPP levels between critically ill AKI (as defined by Risk-Injury-Failure-Loss-End Stage Renal Disease [RIFLE] criteria) and non AKI patients Blood samples were collected from all consecutively admitted patients upon arrival to ICU and daily for up to 4 days We collected 234 blood samples from 86 adult medical and surgical ICU patients The levels of AOPP were determined in the plasma and measured by spectrophotometry at 340 nm and compared between non-AKI (n = 71) and AKI patients (n = 15) We further subdivided the AKI patients according to severity of AM (worst RIFLE class attained in ICU) Results Among the 86 patients, 15 (17 44%) developed AKI during their stay in ICU whereas 71 patients (82 56%) did not Among the AKI patients, 5 had AKI on ICU admission, whereas 10 developed it later The levels of AOPP were significantly higher among AKI patients compared with non AKI patients (153 +/- 117 8 versus 129 0 +/- 114 9 mu mol/L, respectively, P = 034) Patients with the most severe AKI (RIFLE class Failure) had markedly elevated AOPP levels compared with RIFLE class Risk and Injury patients (P = 012) Area under the curve of receiver operating characteristic for prediction of AKI within 48 hours after first blood sample collection was 0 5835 (P = not significant) Conclusions This is the first study to explore the relationship between seventy of AKI and AOPP In our adult ICU population, AOPP levels were higher in AKI compared with non-AKI critically ill patients On the other hand, AOPP levels were not found to be a useful biomarker for AKI as it was unable to identify patients who developed AKI within 24, 48, 76 and 96 hours (C) 2010 Elsevier Inc All rights reserved