OBJECTIVE:Malnutrition is common in chronic kidney disease stage 5 (CKD5) and has negative clinical impacts. The aim of the present study is to evaluate bioimpedance spectroscopy (BIS) in diagnosing malnutrition in CKD5 including hemodialysis and peritoneal dialysis patients (CKD5D) using cutoff values for fat-free mass index (FFMI) according to the Global Leadership Initiative on Malnutrition criteria. Dual-energy X-ray absorptiometry (DXA) was used as a reference method.DESIGN AND METHODS:We performed a single-center cross-sectional diagnostic study of 90 patients with CKD5 or CKD5D.RESULTS:BIS-derived FFMI estimates were significantly higher compared with those obtained by DXA (18.5 ± 2.6 vs.17.8 ± 2.0, P < .05). The mean difference in FFMI estimates between the methods (DXA-BIS) and Bland-Altman 95% limits of agreements is -0.38 (2.76, -3.52) kg/m2. Overhydration (B = 0.67, P < .001), age (B = 0.02, P = .037), and interactions between overhydration and CKD5 subgroups (P = .034) independently predicted bias in BIS-derived FFMI. BIS-derived FFMI showed poor sensitivity (64%) and positive predictive value (48%) in diagnosing malnutrition in the present study population.CONCLUSION:The present study showed a limited agreement between estimates of FFMI derived by BIS and DXA due to a large interindividual variation. Using BIS as a clinical tool for assessing FFMI has limited accuracy and poor sensitivity in diagnosing malnutrition in patients with CKD5 and CKD5D.

ABSTRACT Background We sought to develop a novel non-contrast multiparametric MRI (mpMRI) protocol employing several complementary techniques in a single scan session for a comprehensive functional and structural evaluation of diabetic kidney disease (DKD). Methods In the cross-sectional part of this prospective observational study, 38 subjects ages 18‒79 years with type 2 diabetes and DKD [estimated glomerular filtration rate (eGFR) 15‒60 mL/min/1.73 m2] and 20 age- and gender-matched healthy volunteers (HVs) underwent mpMRI. Repeat mpMRI was performed on 23 DKD subjects and 10 HVs. By measured GFR (mGFR), 2 DKD subjects had GFR stage G2, 16 stage G3 and 20 stage G4/G5. A wide range of MRI biomarkers associated with kidney haemodynamics, oxygenation and macro/microstructure were evaluated. Their optimal sensitivity, specificity and repeatability to differentiate diabetic versus healthy kidneys and categorize various stages of disease as well as their correlation with mGFR/albuminuria was assessed. Results Several MRI biomarkers differentiated diabetic from healthy kidneys and distinct GFR stages (G3 versus G4/G5); mean arterial flow (MAF) was the strongest predictor (sensitivity 0.94 and 1.0, specificity 1.00 and 0.69; P = .04 and .004, respectively). Parameters significantly correlating with mGFR were specific measures of kidney haemodynamics, oxygenation, microstructure and macrostructure, with MAF being the strongest univariate predictor (r = 0.92; P < .0001). Conclusions A comprehensive and repeatable non-contrast mpMRI protocol was developed that, as a single, non-invasive tool, allows functional and structural assessment of DKD, which has the potential to provide valuable insights into underlying pathophysiology, disease progression and analysis of efficacy/mode of action of therapeutic interventions in DKD.

Background Renal transplant biopsies are essential in nephrology; however, they are invasive and complications can occur. Purpose To explore the risk of transplant kidney biopsy (TxB) complications in relation to possible preventive effects of desmopressin prophylaxis. Material and Methods A total of 515 consecutive TxB (375 patients, median age 53 years) were analyzed. In 252 TxB, the Resistive Index (RI) was measured right before the biopsy. A total of 282 patients had serum creatinine >150 µmol/L. In one of the six hospitals 39/282 patients consecutively received desmopressin (dose 0.3 µg/kg subcutaneously) as prophylaxis within 1 h before the biopsy. Fisher’s exact and χ2 test were used (odds ratio [OR], 95% confidence interval [CI]). Univariate and multiple binary logistic regression analyses were performed. A two-sided P value <0.05 was considered significant. Results RI ≥ 0.8 was a risk factor for major TxB complications (OR 4.2, 95% CI 1.13–15.76). The risk for minor complications decreased with mean arterial blood pressure (MAP) (97.9 vs. 89.5 mmHg, OR 0.97, 95% CI 0.95–0.997). In a multiple regression analysis for overall biopsy complications, the risk remained increased for patients with RI ≥ 0.8 (OR 4.45, 95% CI 1.32–15.04). No patients (0/39) with desmopressin prophylaxis had a major complication versus 8/243 in the other group. In patients with serum creatinine >150 µmol/L, those with a higher MAP had more overall TxB complications (104.5 vs. 98.2 mmHg, OR 1.05, 95% CI 1.004–1.1). Conclusion RI ≥ 0.8 was a risk factor for major and overall complications and a lower MAP for minor biopsy complications. Desmopressin prophylaxis showed yet no verified benefit as prophylaxis in TxB.

Purpose: To investigate contemporary results of percutaneous transluminal renal angioplasty (PTRA). Materials and Methods: A multicentre retrospective study analysing all patients treated with PTRA for primary symptomatic renal artery stenosis (RAS) between 2010 and 2013 at four tertiary centres. Procedures during the preceding four years were counted to evaluate for change in PTRA frequency. Results: The number of PTRA procedures decreased by approximately 50% from 2006 to 2013. Patients treated in the post-ASTRAL period (n = 224) had a significant reduction in mean systolic pressure (168 to 146 mmHg, p < 0.01), diastolic pressure (84 to 76 mmHg, p < 0.01), number of anti-hypertensive drugs (3.54 to 3.05, p < 0.01), and anti-hypertensive treatment index (21.75 to 16.92, p < 0.01) compared to before PTRA. These improvements were maintained at one year and at the last clinical evaluation after a mean follow-up of 4.31 years. Renal function increased transiently without sustained improvement, or deterioration, during later follow-up. Thirteen patients (5.8%) eventually required dialysis, nine of these had eGFR Conclusion: The frequency of PTRA has decreased, indicating a higher threshold for invasive treatment of RAS in recent years. The reduction in blood pressures, the reduced need for anti-hypertensive medication, and stabilization of renal function over time suggest a clinical benefit for most patients who are now being treated with PTRA.

Magnetic resonance imaging (MRI) has great potential to non-invasively assess functional and morphologic changes in the kidney that may improve diagnosis, prognosis and treatment in patients with chronic kidney disease (CKD). We investigated in a diabetic nephropathy (DN) population if non-contrast MRI using multiple techniques could differentiate CKD3-4 stages from healthy controls.

Aims: Iron deficiency is common in patients with chronic kidney disease (CKD). Appropriate iron substitution is critical and intravenous iron is an established therapy for these patients. The objective of this study was to assess treatment routine, effectiveness, and safety of iron isomaltoside (Monofer (R), Pharmacosmos A/S, Holbaek, Denmark) in CKD patients in clinical practice. Materials and methods: This was a prospective observational study conducted in predialysis CKD patients treated with iron isomaltoside according to the product label and to routine clinical care. Results: The study included 108 patients with predialysis CKD: 22 were in stage 2 - 3, 41 in stage 4, and 45 in stage 5. The mean (standard deviation) age was 67 (15) years, and 55% of patients were male. The majority of patients (65%) received one iron isomaltoside treatment In patients with a baseline Hb < 10 g/dL, the mean dose of iron isomaltoside in the study was lower than the estimated total iron requirement (567 mg versus 921 mg). A treatment response of Hb >= 1 g/dL was achieved in 16/28 (57%) of patients, and the mean post-treatment Hb level was 10.5 g/dL. The probability of retreatment did not correlate with dose, but no dose administered was > 1,000 mg. There were no serious adverse drug reactions. One nonserious adverse drug reaction - injection site discoloration - was reported, and the patient had an uneventful recovery. Conclusion: Iron isomaltoside shows a good effectiveness and safety profile in predialysis CKD patients. However, some patients did not receive adequate iron doses to allow for optimal correction of their iron deficiency anemia.

Introduction: Renal artery stenosis (RAS) can cause severe hypertension and renal impairment. Pharmacological treatment has improved, and the additional benefit of invasive treatment with percutaneous transluminal renal angioplasty (PTRA) has been questioned since the publication of the ASTRAL trial in 2009 (1). The aim of this study was to investigate contemporary results of PTRA. Methods: Consecutive patients treated with PTRA for primary symptomatic RAS between 2010 and 2013 at four tertiary referral centres were retrospectively reviewed. Information on indications, co-morbidities, procedural details, and treatment results were retrieved from medical records of hospitals, interventional units, and primary care. Measures of outcomes were systolic and diastolic blood pressures, anti-hypertensive medication evaluated by number of drugs and by a calculated anti-hypertensive treatment index, and renal function evaluated by the estimated glomerular filtration rate (eGFR). The number of PTRA procedures done at the participating centres during the preceding four years (2006‒2009) were recorded for comparison, to evaluate change in PTRA frequency Results: The number of PTRA procedures decreased by approximately 50% from 2006 to 2013. Patients treated in the post-ASTRAL period, 2010‒2013, had a significant reduction in mean systolic blood pressure (from 168 to 146 mmHg, p<0.01), mean diastolic blood pressure (84 to 76 mmHg, p<0.01), mean number of anti-hypertensive drugs (3.54 to 3.05, p<0.01), and mean anti-hypertensive treatment index (21.75 to 16.92, p<0.01) compared to before PTRA. These improvements were maintained at one year and at the last clinical evaluation after a mean follow-up of 4.31 years. In contrast, renal function (eGFR) increased only transiently following the PTRA procedure, without sustained improvement during later follow-up. There was no significant difference in outcomes between subgroups differentiated by different indications for PTRA. Conclusion: The frequency of PTRA has decreased, indicating a higher threshold for invasive treatment of RAS in recent years compared to before the publication of the ASTRAL trial. The reduction in systolic and diastolic blood pressures, and the reduced need for anti-hypertensive medication, suggest a clinical benefit for patients who are now being treated with PTRA. References 1. Wheatley K, Ives N, Gray R, Kalra PA, Moss JG, Baigent C, et al. Revascularization versus medical therapy for renal-artery stenosis. The New England journal of medicine. 2009;361(20):1953-62.

Iron deficiency is frequent in haemodialysis (HD) patients with chronic kidney disease (CKD), and intravenous iron is an established therapy for these patients. This study assessed treatment routine, effectiveness, and safety of iron isomaltoside (IIM) 5% (Diafer®) in a HD cohort. This prospective observational study included 198 HD patients converted from iron sucrose (IS) and treated with IIM according to product label and clinical routine. Data for IIM were compared to historic data for IS in 3-month intervals. The primary endpoint was to show non-inferiority for IIM versus IS in haemoglobin (Hb) maintenance. Most patients (> 60%) followed a fixed low-dose iron treatment protocol. Three minutes were required for preparation and administration of IIM. Erythropoiesis-stimulating agent (ESA) was used in > 80% of patients during both IIM and IS phases. The maintenance of Hb was similar with both iron drugs; the mean Hb level was 11 g/dL, and the mean change of 0.3 g/dL (95% confidence interval: 0.1, 0.5) for IIM 0–3 months compared to IS demonstrated non-inferiority. Nine adverse drug reactions were reported in 2% of patients administered IIM. All patients had uneventful recoveries. The frequency of metallic taste was higher with IS compared to IIM (34% versus 0.5%, p < 0.0001). IIM is effective and well tolerated by CKD patients on HD. IIM was non-inferior to IS in maintenance of Hb, and had similar ESA requirements. The fast-push injection of IIM may enable logistical benefits in clinical practice, and the low frequency of metallic taste contributes to patient convenience. ClinicalTrials.gov identifier NCT02301026, study registered November 25, 2014.

New drug development tools are needed for monitoring response to therapy in chronic kidney disease (CKD) with increased precision and repeatability. Magnetic resonance imaging (MRI) has great potential to non-invasively assess functional and morphologic changes in the kidney to improve patient selection and response monitoring in clinical trials for CKD. In this study, we have assessed multiple MRI variables in a diabetic nephropathy (DN) population.

Background Symptomatic renal artery stenosis (RAS) is mainly treated with pharmacological blood pressure control, sometimes with percutaneous transluminal renal angioplasty (PTRA). It is unclear if PTRA benefits these patients over time. Purpose To determine long-term renal function, morbidity, and mortality in patients with symptomatic RAS treated with PTRA, and whether long-term outcomes are associated with angiographic restenosis. Material and Methods Retrospective single-center, long-term follow-up of 57 patients with atherosclerotic RAS treated with PTRA with stent during 1995–2004 and investigated for restenosis with angiography after one year. Outcomes were retrieved from medical records and from mandatory healthcare registries. Mortality rates were related to expected survival in an age- and gender-matched population, using a life-table database. Surviving patients were assessed with blood pressures, laboratory tests, duplex ultrasonography, and radioisotope renography. Results Median follow-up was 11 years 7 months. Major indications for PTRA were therapy-resistant hypertension and declining renal function. Angiographic restenosis at one year was found in 21 of 57 patients (37%). Thirty-six patients (60%) died during follow-up. Main cause of death was cardiovascular events (54%). Mortality was significantly increased, and morbidity and healthcare utilization were high. Hypertension control during follow-up was stable with persistent need for anti-hypertensive medication, and renal function remained moderately reduced with no long-term difference between patients with vs. without restenosis. Conclusion Long-term prognosis after PTRA for atherosclerotic RAS is dismal, with high mortality and morbidity and reduced renal function, despite maintained hypertension control. Restenosis does not appear to affect late outcome.

To evaluate whether the administration of desmopressin alters the risk for renal biopsy complications.

Abstract Objective To evaluate the effect of percutaneous transluminal renal angioplasty (PTRA) on split renal function (SRF) in patients with unilateral atherosclerotic renal artery stenosis (ARAS). Methods We performed a retrospective analysis of all consecutively examined patients at our centre with significant ARAS undergoing PTRA during 2002–07. A significant ARAS was defined as a lesion with a trans-stenotic mean arterial pressure gradient of at least 10 mmHg or a diameter stenosis >50% on angiography. Ambulatory (24 h) systolic and diastolic blood pressure (ASBP and ADBP, respectively) and calculated SRF using 99mTc-DTPA renal scintigraphy were evaluated before (baseline) and 4 weeks after PTRA. Results ASBP and ADBP were significantly lower 4 weeks after PTRA compared with baseline levels. Although total estimated glomerular filtration rate (eGFR; four-variable Modification of Diet in Renal Disease equation) had not changed by PTRA, analysis of SRF showed significantly increased eGFR in stenotic kidneys and a comparable reduction in eGFR in non-stenotic kidneys 4 weeks after PTRA. Conclusions In patients with unilateral ARAS, PTRA significantly improved eGFR in stenotic kidneys and decreased filtration in contralateral, non-stenotic kidneys. These potentially beneficial effects may not be apparent when total renal function remains stable. The clinical significance of these findings needs to be evaluated further.

Background: In Sweden, native and transplant kidney biopsies are usually performed in major renal medical centers.Purpose: To clarify risk factors in native and transplant kidney biopsies to improve patient safety.Material and Methods: A total of 1001 biopsies (in 352 women and 565 men) were included. The median age was 54 years (range, 16-90 years). Data were derived from 826 native kidney biopsies (640 prospective and 186 retrospective) and 175 transplant kidney biopsies (170 prospective and 5 retrospective). Various factors and complications were registered while performing native and transplant kidney biopsies, focusing on major (e. g. blood transfusions, invasive procedures) and minor complications. The prospective protocol was used at six centers and at one center data were obtained retrospectively.Results: Women were at greater risk of overall complications than men (12.2% vs. 6.5%; P = 0.003; odds ratio [OR], 2.0; confidence interval [CI], 1.3-3.1) as well as of major complications (9.6% vs. 4.5%; P = 0.002; OR, 2.2, CI 1.3-3.7). Major complications occurred more commonly after biopsies from the right kidney, in women than in men (10.8% vs. 3.1%; P = 0.005; OR, 3.7; CI, 1.5-9.5), and in patients with lower BMI (25.5 vs. 27.3, P = 0.016) and of younger age (45 years vs. 52.5 years; P = 0.001). Lower mean arterial pressure in transplant kidney biopsies indicated a risk of major complications (90 mmHg vs. 98 mmHg; P = 0.039). Factors such as needle size, number of passes, serum creatinine, and eGFR did not influence complication rates.Conclusion: The present findings motivate greater attention being paid to the risk of major side-effects after right-side biopsies from women's kidneys, as well as after biopsies from younger patients and patients with lower BMI.