AOPP-induced activation of human neutrophil and monocyte oxidative metabolism: A potential target for N-acetylcysteine treatment in dialysis patients

AOPP-induced activation of human neutrophil and monocyte oxidative metabolism: A potential target forN-acetylcysteine treatment in dialysis patients.BackgroundOxidative stress largely contributes to hemodialysis-associated lethal complications, thus explaining the urgent need of antioxidant-based therapeutic strategies in hemodialysis patients. We previously identified advanced oxidation protein products (AOPP) in the uremic plasma as exquisite markers of oxidative stress and potent mediators of monocyte activation. The present study was aimed at searching whether (1) AOPP can also trigger activation of polymorphonuclear neutrophils (PMN), and (2) whether AOPP-induced activation could be inhibited by N-acetylcysteine (NAC), a widely used compound which has been shown to prevent oxidative injury to kidney.MethodsBoth human serum albumin (HAS) AOPP (i.e., HOCl-modified HSA in vitro preparations and AOPP extracted from plasma of hemodialysis patients) were tested for their capacity to trigger phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and myeloperoxidase (MPO)-dependent activities as measured by lucigenin- and luminol-amplified chemiluminescence (CL), respectively, as compared to receptor-dependent [opsonized zymosan or receptor-independent phorbol myristate acetate (PMA)]. The effect of PMN priming by platelet-activating factor (PAF), and the effect of NAC on normal monocyte and on normal or hemodialysis patient's (N = 16) PMN oxidative responses were compared.ResultsHSA-AOPP triggered in a HOCl dose-dependent manner both NADPH-oxidase- and MPO-dependent CL of PMN. This latter was further enhanced by PAF priming. Plasma-derived AOPP obtained from hemodialysis patients also triggered PMN respiratory burst. NAC significantly reduced HSA-AOPP–mediated responses of normal monocyte and of normal and uremic PMN but had no significant effect on opsonized zymosan- or PMA-induced CL responses.ConclusionThis dual potential of NAC to inhibit phagocyte oxidative responses induced by HSA-AOPP without affecting those mediated by compounds mimicking pathogens supports the proposal of a therapeutic trial with NAC aimed at reducing oxidative stress–related inflammation in hemodialysis patients

Hemodialysis without systemic anticoagulation: a prospective randomized trial to evaluate 3 strategies in patients at risk of bleeding.

In this clinical trial, we aimed to compare three means of performing chronic hemodialysis in patients with contra-indication to systemic heparinization.This open-label monocentric randomized « n-of-one » trial, conducted in a single tertiary care center, recruited chronic hemodialysis patients with a contra-indication to systemic heparinization for at least 3 consecutive sessions. All patients underwent hemodialysis with an AN69ST dialyzer, and were administered three alternative dialysis procedures in a random sequence: intermittent saline flushes, constant saline infusion, or pre-dialysis heparin coating of the membrane. The primary outcome was the need to interrupt the dialysis session because of clotting events due to either (i) a complete coagulation of the circuit; (ii) a partial coagulation of the circuit; (iii) a>50% rise over baseline in the venous pressure.At the end of the inclusion period (May, 2007 to December, 2008), the number of patients to include (n=75) was not reached: only 46 patients were included and underwent randomization. The study was terminated, and statistical analysis took into account 224 hemodialysis sessions performed in 44 patients with analyzable data. Heparin adsorption was associated with a significant reduction of the need to interrupt the dialysis session because of clotting events: odds ratio 0.3 (CI 95% 0.2 to 0.6; p3 h dialysis sessions and for having complete blood restitution. There were no significant effects of the dialysis procedure on weight loss, online ionic dialysance, and adverse events.Heparin-coated AN69ST dialysis membrane is a safe and effective method to avoid or delay per-dialytic clotting events in patients with contra-indication to systemic anticoagulation. However, results are not generalizable safely to patients with active bleeding, since weak heparinemia, not assessed in this study, may occur.ClinicalTrials.gov NCT00473109

Allograft function and muscle mass evolution after kidney transplantation

International audienceAdvanced chronic kidney disease is associated with muscle wasting, but how glomerular filtration rate (GFR) recovery after kidney transplantation is associated with muscle mass is unknown

Characteristics of the 44 patients at inclusion.

<p>Characteristics of the 44 patients at inclusion.</p

Dialysis efficiency and tolerance.

<p>CI: confidence interval. OR: Odd Ratio, RC: Regression coefficient, ref: reference OR were computed using a two levels hierarchical logistic mixed model and regression coefficient with a two levels hierarchical linear mixed mode.</p><p>*missing data for 48 sessions;</p><p>**missing data for 23 sessions.</p><p>***p = 0.69 by Fisher’s exact test.</p

Flow Diagram.

<p>Flow Diagram.</p

Course of chronic kidney disease in French patients

Background: In 1998, a French survey showed that the referral of patients with chronic kidney disease to a nephrologist was delayed, resulting in many emergency initiations of dialysis. In 2009, the ORACLE study aimed to describe the renal course of dialysis patients from their first nephrology visit to their first dialysis session.Methods: The ORACLE study was a multicentre retrospective study of all patients who started chronic dialysis. Data were collected at the first nephrology visit and at the first dialysis session.Results: In total, 720 patients were included (69 centres). At the first nephrology visit, the mean Cockcroft-Gault (CG) indicator was 31.8 mL/min (22.7 in 1998) and 52.4% of patients (73% in 1998) had a CG <30. The mean time between the first nephrology visit and the first dialysis session was 48 months (35 months in 1998).Conclusion: In 2009, most patients were referred a long time before dialysis initiation, which likely allowed them to benefit from the impact of nephrology care on early outcomes when on dialysis. However, 34.2% of the dialysis sessions were still initiated under emergency conditions