Multiple single cannulation technique of arteriovenous fistula: A randomized controlled trial.

INTRODUCTION: Despite the impact needling has had on vascular access survival and patient outcome, there is no universal or standardized method proposed for proper cannulation. Rigorous studies are needed, examining cannulation practices, and challenges to achieving complication-free cannulation. METHODS: This randomized, open-label trial was conducted at 18 dialysis units owned by a large private dialysis provider operating in Portugal. Eligible patients were adults on chronic hemodialysis, with a new arteriovenous fistula (AVF); cannulated for at least 4 weeks complication-free. Patients were randomly assigned in a 1:1 ratio to one of three cannulation techniques (CT): Multiple Single cannulation Technique (MuST), rope-ladder (RLC), and buttonhole (BHC). The primary endpoint was AVF primary patency at 1 year. FINDINGS: One hundred seventy-two patients were enrolled between March 2014 and March 2017. Fifty-nine patients were allocated to MuST, 56 to RLC, and 57 to BHC. MuST and RLC were associated with a better AVF primary patency than BHC. Primary patency at 12 months was 76.3% in MuST, 59.6% in BHC, and 76.8% in RLC group. Mean AVF survival times were 10.5 months (95% CI = 9.6, 11.3) in the MuST group, 10.4 months (95% CI = 9.5, 11.2) in RLC, and 9.5 months (95% CI = 8.6, 10.4) in BHC. BHC was a significant risk predictor for AVF survival with 2.13 times more events than the other two CT (HR 2.13; 95% CI = 1.07, 4.21; p = 0.03). DISCUSSION: MuST was easy to implement without a diagram and there is no need to use blunt needles. This study showed MuST was efficacious and safe in maintaining the longevity of AVF in dialysis patients.

RENA Study: Cross-Sectional Study to Evaluate CKD Prevalence in Portugal.

INTRODUCTION: Chronic kidney disease (CKD) is a major global public health problem associated with increased risk of cardiovascular morbidity, premature mortality, and decreased quality of life. In Portugal, the PREVADIAB study showed a prevalence of CKD stages 3-5 of 6.1%. To overcome the limitations of the PREVADIAB study, the RENA study aimed to provide an estimate of the prevalence of CKD at a national level and to characterize CKD patients. METHODS: This was a cross-sectional study including users of Primary Health Care Units aged 18 or more. After obtaining written informed consent, sociodemographic and clinical data were recorded through a structured questionnaire, anthropometric measurements were taken, and blood and urine samples were collected. All participants initially meeting the criteria for CKD were contacted at least 3 months after the initial assessment for confirmation of the analytical results. RESULTS: A total of 3,135 individuals were included, 65.4% were female, and the mean age was 56.7 ± 15.9 years. The prevalence of hypertension, dyslipidemia, and diabetes was 38, 32, and 16%, respectively, and 31% were obese. After data adjustment by gender, age group, and geographical region, the global prevalence of CKD was 20.9% (95% CI: 6.5-35.3%), with no differences between genders and a significant increase with the advance of the age groups. CONCLUSION: Our study showed a CKD prevalence above the worldwide and Europe average. Despite the study limitations, it has become clear that it is urgent to identify CKD patients earlier and to develop awareness and educational programs to prevent CKD and its associated diseases.

Outcomes of acute kidney injury in a nephrology ward.

Acute kidney injury (AKI) is a global problem which predicts immediate and long-term adverse outcomes. We evaluated the AKI progression to end-stage renal disease, as well as the mortality associated with AKI and the in-hospital readmission rate because of a cardiovascular event in AKI patients admitted in a nephrology ward. A 5-year retrospective study was set in a nephrology department, with a follow-up period of up to 8 years. In a total of 191 patients, mean age was 73.83 ± 12.49 years, and 137 (71.7%) patients had history of chronic kidney disease. One hundred and twenty-four (65%) patients needed RRT and two (1%) needed surgery. Upon discharge, 107 (56%) patients had recovered the renal function, 41 (21.6%) patients had partial recovery, 25 (13%) patients were RRT dependent, 16 (8.4%) died, and two (1%) patients had outcomes unknown to us, because they were transferred to other hospitals. The median survival time free of RRT was 74 months. The median survival time of the followed patients was 34 months (95% CI 23.3-44.7). The mortality rate in the follow-up period in this sample was 18 deaths/100 patients-years, and the incidence of a composite cardiovascular endpoint of heart failure, acute coronary syndrome, and stroke was 6 events/100 patients-years. The mortality rate in the follow-up period was higher than usually described for patients outside intensive care unit, probably because our patients were old and had many comorbidities.

CKD Prevalence Varies across the European General Population.

CKD prevalence estimation is central to CKD management and prevention planning at the population level. This study estimated CKD prevalence in the European adult general population and investigated international variation in CKD prevalence by age, sex, and presence of diabetes, hypertension, and obesity. We collected data from 19 general-population studies from 13 European countries. CKD stages 1-5 was defined as eGFR<60 ml/min per 1.73 m(2), as calculated by the CKD-Epidemiology Collaboration equation, or albuminuria >30 mg/g, and CKD stages 3-5 was defined as eGFR<60 ml/min per 1.73 m(2) CKD prevalence was age- and sex-standardized to the population of the 27 Member States of the European Union (EU27). We found considerable differences in both CKD stages 1-5 and CKD stages 3-5 prevalence across European study populations. The adjusted CKD stages 1-5 prevalence varied between 3.31% (95% confidence interval [95% CI], 3.30% to 3.33%) in Norway and 17.3% (95% CI, 16.5% to 18.1%) in northeast Germany. The adjusted CKD stages 3-5 prevalence varied between 1.0% (95% CI, 0.7% to 1.3%) in central Italy and 5.9% (95% CI, 5.2% to 6.6%) in northeast Germany. The variation in CKD prevalence stratified by diabetes, hypertension, and obesity status followed the same pattern as the overall prevalence. In conclusion, this large-scale attempt to carefully characterize CKD prevalence in Europe identified substantial variation in CKD prevalence that appears to be due to factors other than the prevalence of diabetes, hypertension, and obesity.

Methodology used in studies reporting chronic kidney disease prevalence: a systematic literature review.

BACKGROUND: Many publications report the prevalence of chronic kidney disease (CKD) in the general population. Comparisons across studies are hampered as CKD prevalence estimations are influenced by study population characteristics and laboratory methods. METHODS: For this systematic review, two researchers independently searched PubMed, MEDLINE and EMBASE to identify all original research articles that were published between 1 January 2003 and 1 November 2014 reporting the prevalence of CKD in the European adult general population. Data on study methodology and reporting of CKD prevalence results were independently extracted by two researchers. RESULTS: We identified 82 eligible publications and included 48 publications of individual studies for the data extraction. There was considerable variation in population sample selection. The majority of studies did not report the sampling frame used, and the response ranged from 10 to 87%. With regard to the assessment of kidney function, 67% used a Jaffe assay, whereas 13% used the enzymatic assay for creatinine determination. Isotope dilution mass spectrometry calibration was used in 29%. The CKD-EPI (52%) and MDRD (75%) equations were most often used to estimate glomerular filtration rate (GFR). CKD was defined as estimated GFR (eGFR) <60 mL/min/1.73 m(2) in 92% of studies. Urinary markers of CKD were assessed in 60% of the studies. CKD prevalence was reported by sex and age strata in 54 and 50% of the studies, respectively. In publications with a primary objective of reporting CKD prevalence, 39% reported a 95% confidence interval. CONCLUSIONS: The findings from this systematic review showed considerable variation in methods for sampling the general population and assessment of kidney function across studies reporting CKD prevalence. These results are utilized to provide recommendations to help optimize both the design and the reporting of future CKD prevalence studies, which will enhance comparability of study results.

Darbepoetin alfa once monthly corrects anaemia in patients with chronic kidney disease not on dialysis.

AIM: While darbepoetin alfa (DA) can be administered once monthly (QM) to maintain haemoglobin (Hb) concentrations in anaemic patients with chronic kidney disease not on dialysis (CKD-ND), the QM use of DA for anaemia correction has not been previously investigated. METHODS: In this randomized, double-blind, non-inferiority, active-controlled study, adult subjects with CKD-ND, Hb levels <10 g/dL, and not treated with an erythropoiesis-stimulating agent were randomized 1:1 to receive DA every 2 weeks (Q2W) or QM for 33 weeks with initial doses of 0.75 µg/kg Q2W or 1.5 µg/kg QM. Subjects were treated to target Hb levels of 10-12 g/dL and ≥1 g/dL increase from baseline. The primary end-point was Hb change between baseline and the evaluation period (weeks 29-33), with a non-inferiority margin of -0.5 g/dL. RESULTS: Three hundred and fifty-five subjects received ≥1 dose of DA. Mean (95% confidence interval [CI]) change in Hb between baseline and the evaluation period was 2.16 (1.98-2.33) g/dL for the Q2W group and 1.97 (1.80-2.14) g/dL for the QM group, the mean (95% CI) difference in Hb change being -0.19 (-0.43 to 0.05) g/dL. Most subjects (97.9% Q2W; 98.1% QM) achieved a Hb level ≥10.0 g/dL and ≥1.0 g/dL increase in Hb from baseline. Mean DA (SD) weekly equivalent doses over the evaluation period were 0.20 (0.23) and 0.27 (0.31) µg/kg per week for the Q2W and QM groups, respectively. Safety profiles were similar between groups. CONCLUSION: In subjects with CKD-ND, QM dosing was non-inferior to Q2W dosing for anaemia correction and had a similar safety profile.

Amanita poisonings resulting in acute, reversible renal failure: new cases, new toxic Amanita mushrooms.

BACKGROUND: Renal failure as a consequence of eating mushrooms has been reported repeatedly after ingestion of webcaps of the Cortinarius orellanus group. But mushrooms of the genus Amanita can also cause renal failure: Amanita smithiana (North America) and Amanita proxima (Mediterranean area). Here, we discuss poisonings caused by other white amanitas. A German and--independently--two Portuguese patients reported the ingestion of completely white mushrooms with ring. Similar to intoxications with A. smithiana or A. proxima, the clinical picture was characterized by nausea and vomiting 10-12 h after ingestion, severe acute renal failure and mild hepatitis. Renal biopsy showed acute interstitial nephritis and tubular necrosis. Two patients were given temporary haemodialysis. All have fully recovered their renal function. Poisonings caused by mushrooms containing the toxin of A. smithiana were suspected. We tested 20 Amanita species for the presence of this toxin. METHODS: Thin layer chromatography was applied to detect A. smithiana nephrotoxin in herbarium specimens using authentic material of A. smithiana as reference. RESULTS: A. smithiana toxin could be detected in Amanita boudieri, Amanita gracilior and in Amanita echinocephala. A. boudieri was collected by the Portuguese patients. A. echinocephala is the only nephrotoxic Amanita growing North of the Alps and is suspected to be the cause of renal failure in the German patient. No A. smithiana toxin was detectable in the nephrotoxic A. proxima. CONCLUSIONS: A. boudieri, A. gracilior and A. echinocephala are nephrotoxic. These intoxications are clinically similar to that of A. smithiana, with acute reversible renal failure and mild hepatitis but are different in their clinical picture from Orellanus syndrome characterized by a delayed onset of severe and often irreversible renal failure.

Prevalence of chronic kidney disease and associated risk factors, and risk of end-stage renal disease: data from the PREVADIAB study.

BACKGROUND/AIMS: Chronic kidney disease (CKD) is a growing public health problem. However, data on risk factors and prevalence of CKD exist only in a small number of countries. Portugal has the highest incidence of end-stage renal disease (ESRD) among European countries, but there are huge disparities among countries. Whether these disparities reflect differences in risk factors, prevalence of CKD or other factors is currently unknown. METHODS: We analyzed data from a nationally representative sample of 5,167 subjects, and estimated the prevalence of CKD and associated risk factors, and combined these prevalence estimates with available data on ESRD. RESULTS: The prevalence of risk factors such as diabetes (11.7%), obesity (33.7%), and metabolic syndrome (41.5%) was similar to that in the US, but greater than in most European countries. The prevalence of CKD stages 3-5 was 6.1%, which is similar to that in other Western countries. The risk of ESRD was greater than in other European countries, but lower than in the US. CONCLUSION: The high incidence of ESRD among the Portuguese population is not due to a greater prevalence of CKD. A higher rate of progression associated with the high prevalence of risk factors may account for the high incidence of ESRD. The role of unmeasured factors needs to be evaluated in further studies.

Haemolytic uraemic syndrome associated with H1N1 influenza.

Haemolytic uraemic syndrome (HUS) is one of the two forms of thrombotic microangiopathies and is characterized by the triad of microangiopathic haemolytic anaemia, thrombocytopaenia, and acute renal failure. It has been associated with bacterial and viral infections as well as non-infective causes. We report a subject who presented with HUS associated with an influenza-like syndrome which was confirmed as an influenza A (H1N1) infection. There are reports of HUS associated with seasonal influenza, but there have been no reported cases of HUS after novel influenza A (H1N1) in the literature so far.

Inferring disease mechanisms from epidemiological data in chronic kidney disease: calcium and phosphorus metabolism.

BACKGROUND/AIMS: By applying numerical filtering to epidemiological data of 2,512 chronic kidney disease patients, we aimed to identify some of the underlying mechanisms of the calcium/phosphorus metabolism perturbations. METHODS: The measured variables, serum calcitriol, calcidiol, total calcium ([Ca](s)) and phosphorus ([P](s)) and the urinary excretions of calcium and phosphorus, were paired in the same patients with the glomerular filtration rate (GFR) or the serum concentrations of parathormone (i[PTH](s)) (used as independent variables) numerically filtered with a moving average and partitioned into 15-25 frequency classes. All variables exhibited unimodal frequency distributions. RESULTS: There was a steep fall of i[PTH](s), [P](s), and urinary excretion fractions of Ca and P up to a value of GFR in the range of 25-45 ml/min/1.73 m2. The increase in the phosphorus urinary excretion preceded the steep increase in i[PTH](s). Except [Ca](s), all factors exhibited their physiological correlation with i[PTH](s) when GFR was above 90 ml/min/1.73 m2 and reverted to a feedback correlation below 80 ml/min/1.73 m2. CONCLUSION: The perturbation of mineral metabolism in chronic kidney disease results in the maintenance of a normal range of [Ca](s) and [P](s) acting as the controlled factors at the cost of large variations of i[PTH](s), and calcium and phosphate urinary excretions behaving as controlling factors.

Antibody-mediated pure red cell aplasia (PRCA) on switching from darbepoetin alfa to epoetin beta: what are the implications?

We report the development of antibody-mediated pure red cell aplasia (PRCA) in a 63-year-old man with end-stage renal disease following a switch from darbepoetin alfa to epoetin beta. Haemoglobin levels began to decrease 6 months after the switch. Increasing the epoetin beta dose produced no response and regular blood transfusions were required; PRCA was confirmed and epoetin beta was discontinued. The patient responded positively to immunosuppression; after 2 months on prednisone and cyclophosphamide, haemoglobin levels stabilized and no further transfusions were required. This case highlights the difficulty in establishing a cause-effect relationship where more than one erythropoiesis-stimulating agent is involved.

A prospective study on incidence of bacterial infections in portuguese dialysis units.

BACKGROUND: Viral infection has been the main epidemiologic concern in the hemodialysis unit; however, bacterial infection is responsible for more than 30% of all causes of morbidity and mortality in our patients, vascular access infection being the culprit in 73% of all bacteremias. METHODS: A prospective multicenter cohort study of bacterial infections incidence, conducted from January to July 2004 in five hemodialysis units, to record and track bacterial infections, using a validated database from CDC's Dialysis Surveillance Network Program. RESULTS: 4,501 patient-months (P-M) were surveilled, being dialyzed through a native fistula (AVF) in 60.6%, a graft (PTFE) in 31.3%, a tunneled catheter (TC) in 7.6%, and a transient catheter (C) in 0.5%. As target events, we registered 166 hospitalizations - 3.7/100 P-M (2.2/100 P-M in patients with AVF, 4 in PTFE, 9.9 in TC, and 19 in C), and 182 intravenous antibiotic courses. Of these 182 antibiotic treatments, 47.8% included vancomycin, only 30% had blood cultures drawn pretreatment, and only 36% were positive. We recorded 98 infections at the vascular access site 2.18/100 P-M (0.95 in AVF, 1.6 in PTFE, 12.6 in TC, and 42.85 in C) and 2.13 infections/100 P-M at other sites. The isolated microorganisms were Staphylococcus epidermidis in 40.1%, Staphylococcus aureus in 30.1%, Pseudomonas in 13.3%, and Escherichia coli in 3.3%. Although we found a diversity of practice patterns, the number of target events (8.4/100 P-M) and the bacterial infections incidence (4.31/100 P-M) were remarkably homogeneous in the five centers. CONCLUSION: (1) High incidence of bacterial infections, causing major morbidity; (2) infectious risk is vascular access type-dependent, with dramatic rise in catheters; (3) underutilization of blood cultures to orient diagnosis and therapy, and (4) high rates of vancomycin prescription.