Study of the association between serum levels of kynurenine and cardiovascular outcomes and overall mortality in chronic kidney disease.

Background: Kynurenine is a protein-bound uremic toxin. Its circulating levels are increased in chronic kidney disease (CKD). Experimental studies showed that it exerted deleterious cardiovascular effects. We sought to evaluate an association between serum kynurenine levels and adverse fatal or nonfatal cardiovascular events and all-cause mortality in CKD patients. Methods: The CKD-REIN study is a prospective cohort of people with CKD having an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m². Baseline frozen samples of total and free fractions of kynurenine and tryptophan were measured using a validated liquid chromatography tandem mass spectrometry technique. Cause-specific Cox models were used to estimate hazard ratios (HRs) for each outcome. Results: Of the 2406 included patients (median age: 68 years; median eGFR: 25 ml/min/1.73 m2), 52% had a history of cardiovascular disease. A doubling of serum-free kynurenine levels was associated with an 18% increased hazard of cardiovascular events [466 events, HR (95%CI):1.18(1.02,1.33)], independently of eGFR, serum-free tryptophan level or other uremic toxins, cardioprotective drugs, and traditional cardiovascular risk factors. Serum-free kynurenine was significantly associated with non-atheromatous cardiovascular events [HR(95%CI):1.26(1.03,1.50)], but not with atheromatous cardiovascular events [HR(95%CI):1.15(0.89,1.50)]. The association of serum-free kynurenine with cardiovascular mortality was also independently significant [87 events; adjusted HR(95%CI):1.64(1.10,2.40)]. However, the association of serum-free kynurenine with all-cause mortality was no more significant after adjustment on serum-free tryptophan [311 events, HR(95%CI):1.12(0.90, 1.40)]. Conclusions: Our findings imply that serum-free kynurenine, independently of other cardiovascular risk factors (including eGFR), is associated with fatal or nonfatal cardiovascular outcomes, particularly non-atheromatous cardiovascular events; in patients with CKD. Strategies to reduce serum kynurenine levels should be evaluated in further studies.

Point of care creatinine derived eGFR measurement in capillary blood for identifying patients at risk.

Introduction: The aim of the study was to assess the clinical reliability of eGFR values estimated with a creatinine measurement from a point of care (StatSensor®) compared with measured GFR (mGFR) by a gold standard method. Methods: We prospectively included 113 patients undergoing renal function assessment. We compared eGFR using creatinine from capillary blood or venous blood measured by StatSensor® and measured GFR (mGFR) by Passing Bablok regression. Performance of eGFR was estimated by biais, precision and accuracy. Results: A total of 113 subjects were included. Median eGFR values were 59 (10-132), 52 (10-123) and 51 (10-131) ml/min/1.73 m2 for enzymatic, capillary and venous measurements, respectively. There was no difference between P30 and P10 for the three eGFR values (p = 0.11 and p = 0.1 respectively). StatSensor® eGFR tended to be underestimated compared to mGFR. For CKD stage 4/5 patients, concordance was 79 and 84% for eGFR with capillary creatinine and venous creatinine respectively. For mGFR< 60 ml/min/1.73 m2, concordance was 84 and 88% with capillary creatinine and venous creatinine respectively. Conclusion: The use of a handheld blood creatinine monitoring system with eGFR calculation provides a good estimation of GFR and allow to identify patients at high risk of acute kidney injury.

Natriuretic Peptides as Predictors of Protein-Energy Wasting in Hemodialysis Population.

OBJECTIVE: Imbalance between anabolism and catabolism is linked to cachexia and protein-energy wasting (PEW), especially in frail populations such as patients with chronic kidney disease. PEW is responsible of poor outcomes with increased morbidity and mortality. Several causes are involved in PEW such as insulin resistance, acidosis, or hyperparathyroidism. Natriuretic peptides (NPs) have recently been described as activators of resting energy expenditure through the induction of browning of white adipose tissue in rodents with chronic kidney disease. The present study was therefore implemented to investigate whether NPs could be associated with PEW criteria and predict clinical outcomes. METHODS: We quantified serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) in a prospective cohort of 231 patients undergoing maintenance hemodialysis and atrial natriuretic peptide in a subgroup of 35 patients. Body composition parameters were measured with bioimpedance spectroscopy. RESULTS: NT-proBNP was inversely associated with serum albumin, prealbumin, and body mass index and, conversely, positively associated with age and C-reactive protein. NT-proBNP as well as atrial natriuretic peptide were significantly higher in patients with PEW criteria. NT-proBNP was negatively associated with body fat mass. In multiple linear regression, NT-proBNP remained associated with body mass index. Kaplan-Meier analysis revealed a significant correlation between serum NT-proBNP concentrations and all-cause mortality and cardiovascular events. This association remained significant after multivariable Cox regression models adjusted for demographic factors and cardiovascular risk factors. CONCLUSION: Accumulation of NPs seems to be associated with poor nutritional status and reduced survival among hemodialysis patients. Further studies are needed to confirm this association using resting energy expenditure measurement and adipose tissue biopsy.

Is a treat-to-target approach to lipid-lowering therapy appropriate in patients with chronic kidney disease? A prospective French cohort study.

BACKGROUND: Whereas European guidelines recommend adjusting lipid-lowering therapy (LLT) to meet prespecified targets ('treat-to-target') for low-density lipoprotein cholesterol (LDL-C), other guidelines do not ('fire and forget'). In a large observational prospective cohort, we sought to evaluate which strategy could be associated with better cardiovascular outcomes in chronic kidney disease (CKD). METHODS: In CKD-REIN, patients (CKD stages 3 and 4) on LLT were categorized according to achievement of LDL-C targets for high and very high cardiovascular risk (< 2.6 and < 1.8 mmol/L, respectively) at baseline. Primary outcome was fatal/non-fatal atheromatous cardiovascular disease (CVD). Secondary outcomes were non-atheromatous CVD, atheromatous or non-atheromatous CVD, and major adverse cardiovascular events. RESULTS: The population comprised 1521 patients (68 ± 12 years, 31% women, mean estimated glomerular filtration rate [eGFR] 35 mL/min/1.73 m2). Overall, 523 (34%) met their LDL-C targets at baseline. Median follow-up was 2.9 years (interquartile range 2.2-3.0). Incidence rates per 100 patient-years were 6.2% (95% confidence interval [CI] 5.5-7.0) for atheromatous CVD, 9.2% (8.3-10.1) for non-atheromatous CVD, 15.2% (14.0-16.4) for atheromatous/non-atheromatous CVD, and 6.3% (5.5-7.1) for major adverse cardiovascular events. Corresponding rates in patients who achieved targets were 6.6%, 9.8%, 16.1%, and 6.3%, respectively. Target achievement was not associated with risk of fatal/non-fatal atheromatous CVD (adjusted hazard ratio 1.04, 95% CI 0.76-1.44, p = 0.77) or fatal/non-fatal atheromatous or non-atheromatous CVD (0.98, 0.78-1.23, p = 0.91). CONCLUSIONS: These findings do not appear to support a treat-to-target approach in CKD patients on LLT, and may favor the hypothesis of an advantage of fire-and-forget. Randomized trials are needed to confirm this theory.

Urgent-start dialysis in patients referred early to a nephrologist-the CKD-REIN prospective cohort study.

BACKGROUND: The lack of a well-designed prospective study of the determinants of urgent dialysis start led us to investigate its individual- and provider-related factors in patients seeing nephrologists. METHODS: The Chronic Kidney Disease Renal Epidemiology and Information Network (CKD-REIN) is a prospective cohort study that included 3033 patients with CKD [mean age 67 years, 65% men, mean estimated glomerular filtration rate (eGFR) 32 mL/min/1.73 m2] from 40 nationally representative nephrology clinics from 2013 to 2016 who were followed annually through 2020. Urgent-start dialysis was defined as that 'initiated imminently or <48 hours after presentation to correct life-threatening manifestations' according to the Kidney Disease: Improving Global Outcomes 2018 definition. RESULTS: Over a 4-year (interquartile range 3.0-4.8) median follow-up, 541 patients initiated dialysis with a known start status and 86 (16%) were identified with urgent starts. The 5-year risks for the competing events of urgent and non-urgent dialysis start, pre-emptive transplantation and death were 4, 17, 3 and 15%, respectively. Fluid overload, electrolytic disorders, acute kidney injury and post-surgery kidney function worsening were the reasons most frequently reported for urgent-start dialysis. Adjusted odds ratios for urgent start were significantly higher in patients living alone {2.14 [95% confidence interval (CI) 1.08-4.25] or with low health literacy [2.22 (95% CI 1.28-3.84)], heart failure [2.60 (95% CI 1.47-4.57)] or hyperpolypharmacy [taking >10 drugs; 2.14 (95% CI 1.17-3.90)], but not with age or lower eGFR at initiation. They were lower in patients with planned dialysis modality [0.46 (95% CI 0.19-1.10)] and more nephrologist visits in the 12 months before dialysis [0.81 (95% CI 0.70-0.94)] for each visit. CONCLUSIONS: This study highlights several patient- and provider-level factors that are important to address to reduce the burden of urgent-start dialysis.

Adverse outcomes of proton pump inhibitors in patients with chronic kidney disease: The CKD-REIN cohort study.

AIMS: Long-term use of proton pump inhibitors (PPIs) has been associated with adverse kidney events in the general population, but their impact among chronic kidney disease (CKD) patients is unclear. We studied the prevalence and incidence (new users) of PPI prescriptions and their relation to kidney outcomes and mortality in CKD patients. METHODS: We collected drug prescriptions prospectively in a cohort of 3023 nephrology outpatients with CKD stages 2-5 at inclusion. Hazard ratios (HR, 95% confidence intervals [95% CI]) for acute kidney injury (AKI), end-stage kidney disease (ESKD), and mortality associated with new PPI prescriptions as a time-dependent variable were estimated with cause-specific Cox models in 1940 non-users with eGFR ≥ 15 mL/min/1.73 m2 at baseline, adjusted for comorbidities, laboratory data and drugs. RESULTS: There were 981/3023 (32%) prevalent users (67 ± 13 years, 65% men) at baseline, and 366/3023 (12%) were prescribed PPI (new users) over a median follow-up of 3.9 years (interquartile range, 3-4.2). Among these new users, their median cumulative duration of prescription was 1 year (interquartile range: 0.4-2.3). During follow-up, 354 patients developed ESKD and 216 died before ESKD. The adjusted HRs associated with PPI prescription were 1.74 (95% CI, 1.26-2.40) for ESKD and 2.42 (95% CI, 1.73-3.39) for all-cause mortality. Over the first 3 years of follow-up, 211 AKI events had occurred. The adjusted HR for AKI associated with PPI prescription was 2.89 (95% CI, 1.91-4.38). CONCLUSIONS: Long-term PPI prescription was common in CKD patients. Our results call attention to its potential risks of both acute and chronic kidney failure.

Accumulation of natriuretic peptides is associated with protein energy wasting and activation of browning in white adipose tissue in chronic kidney disease.

Protein energy wasting is a common feature of patients with chronic kidney disease (CKD) and is associated with poor outcomes. Protein energy wasting and cachexia, a severe form of protein energy wasting, are characterized by increased resting energy expenditure but the underlying mechanisms are unclear. Browning corresponds to the activation of inducible brown adipocytes in white adipose tissue and occurs in states of cachexia associated with hypermetabolic disease such as cancer. Here we tested the hypothesis that CKD-associated protein energy wasting could result from browning activation as a direct effect of the uremic environment on adipocytes. In a murine model of CKD (5/6 nephrectomy), there was increased resting energy expenditure, expression of uncoupling protein 1 (a thermogenic protein uncoupling oxidative phosphorylation in mitochondria) and citrate synthase activity (a proxy of mitochondrial density in white adipose tissue). Mice with CKD also exhibited increased levels of atrial natriuretic peptide, a well known activator of browning. The incubation of primary adipose cells with plasma from patients receiving dialysis treatment and having signs of protein energy wasting led to an increased synthesis of uncoupling protein 1. Similarly, primary adipose cells exposed to atrial natriuretic peptide at concentrations relevant of CKD led to a significant increase of uncoupling protein 1 content. Thus, accumulation of cardiac natriuretic peptides during CKD could contribute to the browning of white adipose tissue and protein energy wasting.

Adverse Drug Reactions in Patients with CKD.

BACKGROUND AND OBJECTIVES: Little is known about the burden of adverse drug reactions in CKD. We estimated the incidence of overall and serious adverse drug reactions and assessed the probability of causation, preventability, and factors associated with adverse drug reactions in patients seen by nephrologists. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The Chronic Kidney Disease-Renal Epidemiology and Information Network cohort included 3033 outpatients (65% men) with CKD and eGFR<60 ml/min per 1.73 m2, with follow-up for 2 years. Adverse drug reactions were identified from hospitalization reports, medical records, and participant interviews and finally assessed for causality, preventability, and immediate therapeutic management by experts in pharmacology. RESULTS: Median (interquartile range) age was 69 (60-76) years old; 55% had eGFR≥30 ml/min per 1.73 m2, and 45% had eGFR<30 ml/min per 1.73 m2. Participants were prescribed a median (range) of eight (five to ten) drugs. Over 2 years, 536 patients had 751 adverse drug reactions, 150 (in 125 participants) classified as serious, for rates of 14.4 (95% confidence interval, 12.6 to 16.5) and 2.7 (95% confidence interval, 1.7 to 4.3) per 100 person-years, respectively. Among the serious adverse drug reactions, 32% were considered preventable or potentially preventable; 16 caused death, directly or indirectly. Renin-angiotensin system inhibitors (15%), antithrombotic agents (14%), and diuretics (10%) were the drugs to which the most adverse drug reactions were imputed, but antithrombotic agents caused 34% of serious adverse drug reactions. The drug was discontinued in 71% of cases, at least temporarily. Adjusted hazard ratios for serious adverse drug reaction were significantly higher in patients with eGFR<30 versus ≥30 ml/min per 1.73 m2 (1.8; 95% confidence interval, 1.3 to 2.6), in those prescribed more than ten versus less than five medications (2.4; 95% confidence interval, 1.1 to 5.2), or in those with poor versus good adherence (1.6; 95% confidence interval, 1.4 to 2.4). CONCLUSIONS: Adverse drug reactions are common and sometimes serious in patients with CKD. Many serious adverse drug reactions may be preventable. Some specific pharmacologic classes, particularly antithrombotic agents, are at risk of serious adverse drug reactions. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN), NCT03381950.

Predictive factors of renal involvement in cryoglobulinaemia: a retrospective study of 153 patients.

BACKGROUND: The course of cryoglobulinaemia varies widely, from asymptomatic patients to severe vasculitis syndrome. Renal involvement (RI) is the major prognostic factor, and frequently occurs several years after diagnosis. However, predictive factors for RI are not well known. The aim of our study was to identify RI predictive factors during cryoglobulinaemia. METHODS: We retrospectively reviewed the clinical charts of a consecutive series of 153 patients positive for cryoglobulinaemia in the University Hospital of Lyon (France). RI was defined either histologically or biologically if cryoglobulinaemia was the only possible cause of nephropathy. RESULTS: Among the 153 positive patients (mean age 55 years, 37% male), cryoglobulinaemia was associated with RI in 45 (29%) patients. Sixty-five percent of patients had Type II cryoglobulinaemia, 28% had Type III and 7% had Type I. Autoimmune diseases were the most common aetiology (48%), followed by infectious diseases (18%) and lymphoproliferative disorders (13%). Membranoproliferative glomerulonephritis was the main histological pattern (93% of the 14 histological analyses). A multivariable logistic regression showed that Type II cryoglobulinaemia, a high serum cryoglobulin concentration, the presence of an IgG kappa monoclonal component and diabetes were independently associated with the risk for developing RI. CONCLUSION: We identified several factors predictive of RI in patients with cryoglobulinaemia, which were different from the diagnostic criteria for cryoglobulinaemic vasculitis. This could suggest a specific pathophysiology for RI. We suggest performing an extensive renal monitoring and ensure nephroprotection when a diagnosis of cryoglobulinaemia is made in patients with these predictive factors.

Risk profile, quality of life and care of patients with moderate and advanced CKD: The French CKD-REIN Cohort Study.

Background: The French Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort study was designed to investigate the determinants of prognosis and care of patients referred to nephrologists with moderate and advanced chronic kidney disease (CKD). We examined their baseline risk profile and experience. Methods: We collected bioclinical and patient-reported information from 3033 outpatients with CKD and estimated glomerular filtration rates (eGFRs) of 15-60 mL/min/1.73 m2 treated at 40 nationally representative public and private facilities. Results: The patients' median age was 69 (60-76) years, 65% were men, their mean eGFR was 33 mL/min/1.73 m2, 43% had diabetes, 24% had a history of acute kidney injury (AKI) and 57% had uncontrolled blood pressure (BP; >140/90 mmHg). Men had worse risk profiles than women and were more likely to be past or current smokers (73% versus 34%) and have cardiovascular disease (59% versus 42%), albuminuria >30 mg/mmol (or proteinuria > 50) (40% versus 30%) (all P < 0.001) and a higher median risk of end-stage renal disease within 5 years, predicted by the kidney failure risk equation {12% [interquartile range (IQR) 3-37%] versus 9% [3-31%], P = 0.008}. During the previous year, 60% of patients reported one-to-two nephrologist visits and four or more general practitioner visits; only 25% saw a dietician and 75% were prescribed five or more medications daily. Physical and mental quality of life (QoL) were poor, with scores <50/100. Conclusions: The CKD-REIN study highlights high-risk profiles of cohort members and identifies several priorities, including improving BP control and dietary counselling and increasing doctors' awareness of AKI, polypharmacy and QoL. Trial registration: ClinicalTrials.gov identifier: NCT03381950.

Serum levels of the adipokine zinc-alpha2-glycoprotein (ZAG) predict mortality in hemodialysis patients.

Wasting has been associated with increased cardiovascular and all-cause mortality in chronic kidney disease (CKD). We investigated whether serum zinc-alpha2-glycoprotein (ZAG), a potent cachectic and lipid-mobilizing factor that is increased in patients with CKD, predicts clinical outcomes in patients on chronic hemodialysis. We quantified serum ZAG at baseline in a prospective cohort of 252 patients undergoing maintenance hemodialysis. Serum ZAG concentrations were inversely associated with serum albumin, creatinine, and triglycerides and, conversely, positively associated with age. Although ZAG is strongly linked to protein energy wasting (PEW) in patients with cancer, higher ZAG concentrations were not associated with PEW in our cohort. During a mean study follow-up of 954 days, 49 patients died and 62 patients experienced a cardiovascular event. Kaplan-Meier analysis revealed a significant correlation between serum ZAG concentrations and all-cause mortality and cardiovascular events. In separate multivariable Cox regression models, serum ZAG concentrations remained significantly associated with all-cause mortality and cardiovascular events after adjustment for demographic factors (age, sex, and dialysis vintage), metabolic parameters (serum albumin, prealbumin, triglycerides, cholesterol, normalized protein catabolic rate, and body mass index), and cardiovascular risk factors (diabetes, dyslipidemia, history of cardiovascular disease, smoking, and diuretic use as a proxy of residual renal function). Thus, serum ZAG appears to be a strong and independent predictor of mortality and cardiovascular events in patients with end-stage renal disease. Further studies are necessary to confirm this association and to elucidate the underlying mechanisms.

Adjunction of a MEK inhibitor to Vemurafenib in the treatment of metastatic melanoma results in a 60% reduction of acute kidney injury.

INTRODUCTION: A combined therapy MEK inhibitor, Cobimetinib (CB) and BRAF inhibitor, Vemurafenib (VMF), results in an improvement in progression-free survival among patients with BRAF V600-mutated metastatic melanoma. VMF skin adverse effects attributed to ERK paradoxical activation are decreased by the adjunction of CB. The aim of this study was to determine if this combination also improved the renal side effects of VMF. PATIENTS AND METHODS: To investigate the incidence of acute kidney injury (AKI), we conducted a retrospective observational monocentric study in Lyon Sud University Hospital in France. We included 38 patients with metastatic BRAF-mutated melanomas treated by VMF and CB between March 2015 and June 2016. According to the NCI-CTCAE classification, AKI was defined as an increase in serum creatinine exceeding the baseline concentration by 1.5-fold. Serum creatinine was measured before treatment, then on a monthly basis during treatment, and 1 month after treatment discontinuation. Patients were divided into two main groups: AKI-positive (AKI+) and AKI-negative (AKI-), and further subdivided into three groups according to AKI severity (stage 1-5). RESULTS: Of 38 patients, 29 (76%) were AKI-, and all 9 AKI+ patients (24%) were diagnosed within the first trimester of treatment. Three-quarters of AKI (n = 7, 77%) had stage 1 AKI and the remaining 23% stage 2 AKI. Pre-treatment renal function was significantly better in AKI+ group: 105 vs. 80 ml/min/1.73m² AKI-, p = 0.009. Compared to previous results, the AKI incidence under the combined VMF-CB vs. VMF monotherapy was reduced by 60%. CONCLUSION: We reported a reduced incidence and severity of nephrotoxicity of the association inhibitors of BRAF and MEK compared to a BRAF inhibitor monotherapy.

New insights into renal toxicity of the B-RAF inhibitor, vemurafenib, in patients with metastatic melanoma.

PURPOSE: Vemurafenib (VMF) is a B-RAF inhibitor used in the treatment of B-RAF-V600-mutant metastatic melanomas. Reports of acute kidney injury (AKI) in patients treated with VMF are scarce. METHODS: To investigate the incidence and severity of AKI, we conducted a retrospective, observational, monocentric study in the Lyon Sud Hospital University, France, which included 74 patients with metastatic B-RAF-mutated melanomas treated with VMF, between June 2011 and August 2014. According to the Kidney Disease Improving Global Outcomes Guidelines, AKI is defined as an increase in serum creatinine concentration exceeding the baseline concentration by 1.5 fold. Serum creatinine was thus determined before treatment, on a monthly basis during treatment, and 3 months after treatment discontinuation. Patients were divided into two main groups: AKI-positive (AKI+) and AKI-negative (AKI-) and further subdivided into three groups according to AKI severity (stage 1, 2 or 3). To visualize the tissue damage caused by VMF, kidney biopsies were performed for two stage 1 AKI+ patients. RESULTS: Of the 74 patients, 30 (40.5 %) were AKI-, and of the 44 AKI+ patients (59.5 %), 29 (66 %) were diagnosed within the first three months of treatment. There were significantly more men in the AKI+ group: n = 33 (75 %) versus n = 12 (40 %) women, p = 0.004 with an odds ratio for developing AKI of 4.6 (95 % CI 1.48-14.23). Most AKI + cases were considered as stage 1 (n = 40; 91 %) and the remaining four (9 %) as stage 2 AKI. Kidney biopsies revealed interstitial fibrosis and acute focal tubular damage. However, renal failure was reversible in 80 % of patients within 3 months of VMF discontinuation. CONCLUSIONS: We observed frequent, reversible, moderately severe AKI with some histological evidence of tubular and interstitial damage in VMF-treated patients, suggesting that renal function should be carefully monitored in male patients, especially during the first 3 months.

[Conservative treatment, hemodialysis or peritoneal dialysis for elderly patients: The choice of treatment does not influence the survival]. / Traitement conservateur, hémodialyse ou dialyse péritonéale chez le sujet âgé : le choix du traitement ne modifie pas la survie.

Hemodialysis is the predominant replacement therapy in the 70 year-old French population (18% in peritoneal dialysis, 72% in hemodialysis from the REIN registry). Managing older patients reaching the end stage renal disease poses many ethical questions, since outcomes balanced regarding survival and quality of life. The aim of this study was to compare the survival of patients aged over 70 years according to the ESRD treatment choice: conservative treatment without dialysis (CT), hemodialysis (HD) and peritoneal dialysis (PD). We included all patients over 70 years reaching stade IV CKD integrated in a predialysis information program between 01/01/2005 and 31/12/2010. We compared their survival from the start of their program, in function of their treatment choice: HD, PD or CT. On this period, 148 patients were included, we excluded from analysis 17 patients who had a contraindication to PD, 26 patients who did not make a choice because their kidney function was stabilized, 4 patients lost to follow-up and 12 patients who died before the treatment choice. The average age was 79±6 years, 40% of patients were women, and the mean eGFR was 16±9 mL/min/1.73 m(2) at the entry in the program. Among the 89 patients, 21 choose CT (24%), 68 accepted dialysis (76%), including 48 HD (71%) and 20 PD (29%). No significant eGFR difference at the inclusion time between the groups. The time initiation of dialysis was significantly shorter in the PD group (146 days vs 442 in the HD group; P=0.004). Survival between the groups of patients who accepted or refused dialysis was not statistically different (749 days or 2 years in the HD + PD group vs 562 days, or 1 year and 6 months in the CT group; P=0.95) and between the HD group (760 days or 2 years and 2 months) and the PD group (343 days or 11 months; P=0.32). As measured from the time they entered in the predialysis program, the survival of older patients over 70 years does not seem to depend on their choice of treatment modality. Whether they accepted or refused dialysis, whatever their choice concerning hemodialysis or peritoneal dialysis, their survival was close to one year.

Postconditioning with cyclosporine a reduces early renal dysfunction by inhibiting mitochondrial permeability transition.

BACKGROUND: Ischemia-reperfusion (IR) injury leads to mitochondrial permeability transition pore opening, which contributes to cell death. The aim of this study is to determine whether ischemic or pharmacological postconditioning with cyclosporine A (CsA) might protect the kidney from lethal reperfusion injury. METHODS: Male mice underwent a unilateral (right) nephrectomy followed by 30 minutes of contralateral (left) clamping of the renal artery. We studied 4 groups at 20 minutes and 24 hours of reperfusion: a sham group (n = 4), an ischemic group (n = 6), CsA-postconditioned group (postcond-CsA, injection of 3 mg/kg of CsA 5 minutes before the end of ischemia, (n = 6), and an ischemic postconditioning (IPC) group (n = 6), consisting of 3 cycles of 30 seconds of renal ischemia with 30 seconds intervening reperfusion. After 24 hours of reperfusion, we measured plasma creatinine, urea, and histological kidney injury. The kidney mitochondria were isolated to assess the mitochondria calcium retention capacity and oxidative phosphorylation. RESULTS: At 24 hours after reperfusion, serum creatinine decreased in postcond-CsA and IPC compared to ischemic group. The histological score was also significantly improved with postcond-CsA and IPC. At 20 minutes and 24 hours of reperfusion, calcium retention capacity was decreased significantly in the ischemic group. The mitochondrial respiration stay decreased in the ischemic group at 24 hours of reperfusion, whereas the respiration was improved significantly in the postcond-CsA and IPC group. Bax and cleaved caspase 3 decreased in PostCsA and IPC group. CONCLUSIONS: Our results suggest that IPC and CsA, administered immediately before reperfusion, protect the kidney from lethal injury.

The spectrum of renal involvement in patients with inflammatory myopathies.

Data regarding the incidence and outcome of renal involvement in patients with inflammatory myopathies (IM) remain scarce. We assessed the incidence and causes of acute kidney injury (AKI) and chronic kidney disease (CKD) in 150 patients with dermatomyositis, polymyositis, and antisynthetase syndrome followed in 3 French referral centers. Renal involvement occurred in 35 (23.3%) patients: AKI in 16 (10.7%), and CKD in 31 (20.7%) patients. The main cause of AKI was drug or myoglobinuria-induced acute tubular necrosis. Male sex, cardiovascular risk factors, cardiac involvement, and initial proteinuria >0.3 g/d were associated with the occurrence of AKI. The outcome of patients with AKI was poor: 13 (81%) progressed to CKD and 2 (12.5%) reached end-stage renal disease. In multivariate survival analysis, age at IM onset, male sex, a history of cardiovascular events, and a previous episode of AKI were associated with the risk of CKD. We also identified 14 IM patients who underwent a kidney biopsy in 10 nephrology centers. Renal pathology disclosed a wide range of renal disorders, mainly immune-complex glomerulonephritis. We identified in 5 patients a peculiar pattern of severe acute renal vascular damage consisting mainly of edematous thickening of the intima of arterioles. We found that AKI and CKD are frequent in patients with IM. Prevention of AKI is crucial in these patients, as AKI is a major contributor to their relatively high risk of CKD. A peculiar pattern of acute vascular damage is part of the spectrum of renal diseases associated with IM.

[Secondary hyperparathyroidism and anemia. Effects of a calcimimetic on the control of anemia in chronic hemodialysed patients. Pilot Study]. / Hyperparathyroïdie secondaire et anémie. Effets d'un calcimimétique sur le contrôle de l'anémie des hémodialysés chroniques. Étude pilote.

UNLABELLED: The main cause of resistance to erythropoiesis-stimulating agents (ESA) used for treatment of anemia in chronic hemodialysed patients (CHP) is the iron deficiency, absolute or functional. Secondary hyperparathyroidism (SHPT) is a secondary factor of resistance. Indeed, it has been reported in the literature an improvement of anemia parameters after surgical parathyroidectomy (PTX). The objective of this study is to assess in CHP, the impact of the correction of SHPT by a calcimimetic, cinacalcet (CI), (which is considered as a pharmacological PTX) on the response to ESA, measured by the erythropoietin resistance index (ERI). Twenty-two CHP with severe SHPT documented by an intact parathyroid hormone (iPTH) above 800pg/mL were included in this prospective pilot study. Mineral bone metabolism, anemia and nutritional parameters were measured baseline and after 6 months of treatment by CI. The effect on anemia was assessed at the end of study by the ERI, the change in Hb concentration, and the proportion of patients with Hb levels above 11g/dL. RESULTS: At the end of study there was a significant decrease (M6 vs M0) in iPTH (1302 vs 674pg/mL or -48%, p=0.006), serum calcium (2.39 vs 2.15mmol/L or -10%), serum phosphate (2 vs 1.7mmol/L or -15%), serum calcium-phosphorus product (CaxP) (4.8 vs 3.8mmol(2)/L(2) or - 20% (p<0.05), and the number of patients with CaxP>4.4mmol(2)/L(2) (64 vs 32%, p<0.05). The level of bone alkaline phosphatase remained stable during the study (28 vs 27 IU/L). The Hb levels increased from 11 to 11.4g/dL, as did the proportion of patients whose Hb concentration reached 11g/dL or higher (50 vs 70%, p<0.05) without important change of the median weekly ESA dosis in the majority of patients, 18 cases (81%) vs four (19%). Two subgroups were identified from the median decreases in iPTH (delta iPTH) between M0 and M6, Group 1 (delta iPTH≥400pg/mL, n=10) and group 2 (delta iPTH<400pg/mL, n=12): in group 1, we found a correlation between the decrease in iPTH by CI and the stability or decrease in ERI (group 1), at comparable dose of dialysis, nutritional and iron intakes and inflammatory profiles; in group 2 without a significant effect of CI on PTH reduction the levels of ERI and ESA dosis were more elevated. CONCLUSION: A treatment by calcimimetic improves the control of anemia by ESA in CHP and interferes positively on a cause of secondary resistance to ESA represented by SHPT. The mechanism of these effects could be linked to the decreased of bone marrow fibrosis and inflammation and to the triptych formed by the reduction in iPTH, CaxP and phosphate.

[Renal consequences of obesity]. / Conséquences rénales de l'obésité

The steady increase in the prevalence of obesity contributes to the increase in the prevalence of chronic kidney disease, through renal damages associated with type-2 diabetes and hypertension. Obesity is also an independent risk factor for the kidney, since it is associated with an increased risk of albuminuria and glomerulosclerosis, and worsens the course of chronic kidney disease regardless of the primary renal disease. The existence of a metabolic syndrome, constant in type-2 diabetes, and associated with abdominal obesity, is not the only requirement for renal anomalies of which the translation is a functional hyperfiltration, a clinical microalbuminuria and histologically a glomerulomegaly and glomerulosclerosis. The estimated glomerular filtration rate (GFR) in obese patients is strongly influenced by the weight or indexation to body surface area, and it is logical to take into account the value of non-indexed GFR to assess renal risk and treatment effects, especially if they lead to weight loss. Hypertension is promoted by salt sensitivity, potentially reversible, and overactivity of the renin-angiotensin system (RAS) in part due to adipose tissue. The cytokines secreted by adipose tissue (adipokines), induce sympathetic hyperactivity through leptin, and low-grade inflammatory state that contributes to the development of glomerular sclerosis lesions, especially because a resistance to adiponectin. The treatment relies on weight loss, possibly through bariatric surgery, and antagonists of the RAS.

[Direct medical cost of erythropoiesis-stimulating agents in anaemia treatment of chronic renal failure patient: a literature review]. / Coût médical direct des agents stimulant l'érythropoïèse dans le traitement de l'anémie chez le patient insuffisant rénal chronique: revue de la littérature.

INTRODUCTION: Management of anaemia in chronic renal insufficiency (CRI) represents an important medico-economic challenge because of the great number of patients and the cost of the erythropoiesis-stimulating agent (ESA). The aim of this study was to identify determinants of the costs associated with these treatments in order to choose, with equal efficacy, the most efficient ASE. METHOD: A bibliographic research was realised by Medline database interrogation. RESULTS: Among the direct medical costs, five studies showed that acquisition of epoetine alfa (EA) compared to darbepoetin alfa (DA) was less expensive. Concerning the costs associated with the route of administration, the subcutaneous injection (SC) of epoetine allowed a gain in costs because of the decrease of doses compared to the intravenous (IV) route. The switch from EA in SC to DA in IV, for hemodialysis patients, was associated with a reduction of the number of injections and with a treatment's cost lower by DA than by EA. Costs related to the regimen of administration, notably those related to nursing, medical and pharmaceutical time, were negligible towards those associated to the acquisition of the ASE. Finally, the costs of the therapeutic follow-up and treatment of the adverse effects of the ASE were similar between the EA and the DA. CONCLUSION: The costs associated with the prices of acquisition of the ASE, negotiated by the structure of care, represent the most important part of the direct medical costs.