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Diabetes mellitus (DM) is an important predictor of neointimal hyperplasia (NIH) and adverse clinical outcomes after percutaneous coronary intervention (PCI). LABR-312, a novel intravenous formulation of liposomal alendronate, has been shown in animal models to decrease NIH at vascular injury sites and around stent struts. The aim of the Biorest Liposomal Alendronate Administration for Diabetic Patients Undergoing Drug-Eluting Stent Percutaneous Coronary Intervention trial was to assess the safety, effectiveness, and dose response of LABR-312 administered intravenously at the time of PCI withDES in reducing NIH as measured by optical coherence tomography postprocedure in patients with DM.Patients with DM were randomized to a bolus infusion of LABR-312 vs placebo at the time of PCI. Dose escalation of LABR-312 in the study arm was given: 0.01 mg, 0.03 mg, and 0.08 mg. The primary endpoint was the in-stent %NIH volume at 9 months as measured by optical coherence tomography.From September 2016 to December 2017, 271 patients with DM undergoing PCI were enrolled; 136 patients were randomized to LABR-312 infusion and 135 patients were randomized to placebo. At 9-month follow-up, no difference was seen in the primary endpoint of %NIH between LABR-312 and placebo (13.3% ± 9.2 vs 14.6% ± 8.5, P = .35). No differences were present with the varying LABR-312 doses. Clinical outcomes at 9 months were similar between groups.Among patients with DM undergoing PCI with drug-eluting stents, a bolus of LABR-312 injected systematically at the time of intervention did not result in a lower rate in-stent %NIH volume at 9-month follow-up.

Keratin-based hair straightening treatment is a popular hair styling method. The majority of these products in Israel contain glycolic acid derivatives, which are considered safe when used topically. Systemic absorption of these products is possible and anecdotal reports have described kidney toxicity associated with their use. We report a series of cases of severe AKI following use of hair-straightening treatment occurring in Israel over the past several years.Case series.We retrospectively identified 26 patients from 14 medical centers in Israel who developed severe AKI and reported prior treatment with hair-straightening products between 2019 and 2022.The 26 patients described had a median age of 28.5 years (range, 14-58) and developed severe AKI following hair-straightening procedure. The most common symptoms at presentation were nausea, vomiting, and abdominal pain. Scalp rash was noted in 10 (38%) patients. Two patients developed a recurrent episode of AKI following a repeat hair-straightening treatment. Seven patients underwent kidney biopsies that demonstrated intra-tubular calcium oxalate deposition in six and microcalcification in tubular cells in one. In all biopsies, signs of acute tubular injury were present, and an interstitial infiltrate was noted in four cases. Three patients required temporary dialysis.Retrospective uncontrolled study, small number of kidney biopsies.This study describes cases of acute kidney injury with prior exposure to hair straightening treatments. Acute oxalate nephropathy was the dominant finding on kidney biopsies, which may be related to absorption of glycolic acid derivatives and their metabolism to oxalate. This case series suggests a potential under-recognized cause of AKI in the young healthy population. Further studies are needed to confirm this association and to assess the extent of this phenomenon as well as its pathogenesis.

BackgroundChronic kidney disease (CKD) is associated with poorer outcomes following percutaneous coronary intervention (PCI) with drug-eluting stents. Drug-eluting balloons are used for in-stent restenosis and selected cases of de-novo coronary lesions. Little is known regarding the outcomes of individuals with CKD who undergo PCI with drug-eluting balloons. The goal of this study was to assess outcomes of PCI with drug-eluting balloons in individuals with CKD.MethodsIn a retrospective analysis, outcomes of PCI with drug-eluting balloons were compared between 101 patients with CKD and 261 without CKD. CKD was defined as estimated glomerular filtration rate 2. We compared demographics, procedure data and clinical outcomes in the first and second years following the procedure.ResultsRates of major adverse cardiac events (MACE) and myocardial infarction were higher in patients with than without CKD: 23.8% vs. 13.8%,P P P = 0.4. Shorter duration of dual anti-platelet therapy was observed among patients with than without CKD (10.0 + 3.4 vs. 10.9 + 3.7 months,P P = 0.2). In a multivariate regression analysis, CKD was associated with increased risks of first year MACE (OR 2.1; 95% confidence interval 1.0-4.3,P ConclusionsPCI with drug-eluting balloons was associated with increased cardiovascular morbidity and mortality in patients with than without CKD. However, rates of target lesion revascularization were similar in the two groups. Shorter duration of dual anti-platelet therapy was observed in the CKD group.

Bartonella henselae endocarditis mimicking systemic vasculitis has been reported in patients with valvulopathy. Herein, we describe a patient with B. henselae endocarditis involving a prosthetic pulmonic valve with positive anti-dsDNA antibodies misdiagnosed with systemic lupus erythematosus (SLE) based on the revised classification SLE criteria.

Introduction Severe aortic stenosis (AS) is the most common valvular heart disease in the western world. Various factors are related to severe AS prognosis, including chronic kidney disease. The aim of this study was to evaluate the prognostic value of urea level in patients with severe AS. Methods We prospectively enrolled 142 patients (79.1±9.4 years, 88 women) with severe AS (mean valve area 0.67± 0.17 cm2). Clinical assessment, blood tests and echocardiography were performed at enrollment and follow up. The patient population was divided into low and high urea level groups, according to the median urea level at enrollment (72 patients, mean urea 35.5±6.2 mg/dL and 70 patients, mean urea 61.1±17.8 mg/dL, respectively). Hundred and twelve patients (79%) underwent aortic valve intervention. The primary endpoint was all-cause and cardiovascular mortality. Outcomes During follow-up of 37±19.5 months, 56 (37.1%) patients died, 39 due to cardiovascular causes. In univariate analysis, age, urea level, creatinine, New York Heart Association (NYHA) class and aortic valve intervention were associated with all-cause mortality. However, in multivariate analysis only aortic valve intervention and blood urea were independent predictors of all-cause mortality (HR 0.494; 95% CI 0.226-0.918, P = 0.026 and HR 1.015; 95% CI 1.003-1.029, P = 0.046 respectively). Urea level, NYHA class and age were also significant predictors of cardiovascular mortality. Whereas, in multivariate analysis, only urea level predicted cardiovascular mortality in these patients (HR 1.017; CI 1.003-1.031 P = 0.019). Conclusions Blood urea, a generally readily available and routinely determined marker of renal function, is an independent prognostic factor in patients with severe AS.

Background and objectives Steroid-resistant nephrotic syndrome overwhelmingly progresses to ESRD. More than 30 monogenic genes have been identified to cause steroid-resistant nephrotic syndrome. We previously detected causative mutations using targeted panel sequencing in 30% of patients with steroid-resistant nephrotic syndrome. Panel sequencing has a number of limitations when compared with whole exome sequencing. We employed whole exome sequencing to detect monogenic causes of steroid-resistant nephrotic syndrome in an international cohort of 300 families. Design, setting, participants, & measurements Three hundred thirty-five individuals with steroid-resistant nephrotic syndrome from 300 families were recruited from April of 1998 to June of 2016. Age of onset was restricted to Results In 74 of 300 families (25%), we identified a causative mutation in one of 20 genes known to cause steroid-resistant nephrotic syndrome. In 11 families (3.7%), we detected a mutation in a gene that causes a phenocopy of steroid-resistant nephrotic syndrome. This is consistent with our previously published identification of mutations using a panel approach. We detected a causative mutation in a known steroid-resistant nephrotic syndrome gene in 38% of consanguineous families and in 13% of nonconsanguineous families, and 48% of children with congenital nephrotic syndrome. A total of 68 different mutations were detected in 20 of 33 steroid-resistant nephrotic syndrome genes. Fifteen of these mutations were novel. NPHS1, PLCE1, NPHS2, and SMARCAL1 were the most common genes in which we detected a mutation. In another 28% of families, we detected mutations in one or more candidate genes for steroid-resistant nephrotic syndrome. Conclusions Whole exome sequencing is a sensitive approach toward diagnosis of monogenic causes of steroid-resistant nephrotic syndrome. A molecular genetic diagnosis of steroid-resistant nephrotic syndrome may have important consequences for the management of treatment and kidney transplantation in steroid-resistant nephrotic syndrome.

Dialysis patients have a suboptimal response to hepatitis B (HBV) vaccination. This study aimed to compare the immunogenicity of two vaccines: the third-generation Sci-B-Vac™ vs. the second-generation Engerix B®. The cohort included two groups of dialysis patients: naive and previously vaccinated non-responders. Primary endpoints were antibody titers ≥10 IU/L at 3 and 7 month post-vaccination. Secondary objectives were seroprotection rates in vaccine-naive patients and in previously vaccinated non-responders. Eighty-six patients were assigned to vaccine (Sci-B-Vac™ or Engerix B®) using computer-generated randomization, stratified by age, gender, diabetes, and previous HBV vaccination. Sci-B-Vac™ was administered in three doses, 10 μg, at 0, 1, and 6 months in naive patients; or 20 μg in previously vaccinated non-responders. Engerix B® included four doses, 40 μg at 0, 1, 2, and 6 months. Each group had 43 patients. Seroconversion was 69.8% with Engerix B® vs. 73.2% with Sci-B-Vac™. Antibody titers at 7 months were higher with Sci-B-Vac™ (266.4 ± 383.9, median 53.4) than with Engerix® (193.2 ± 328.9, median 19). However, these differences were not significant, perhaps due to a suboptimal sample size. This study suggests comparable immunogenicity for both vaccines. Thus, we cannot reject the null hypothesis that there is no difference in seroconversion by vaccine type. It is noteworthy that naive patients were vaccinated with a standard dose of Sci-B-Vac™, while Engerix B® was administered at a double dose. Similarly, although mean antibody titer levels in the Sci-B-Vac™ group were higher than in the Engerix® group, this difference did not reach significance. Consequently, a future clinical trial should recruit a larger cohort of patients, using a standard double-dose protocol in both groups.

Background MicroRNAs are short non-coding RNAs that regulate gene expression. The aim of this study was to gain an understanding of the possible role of the miR-106b~ 25 microRNA cluster in regulating atherosclerosis in mice. Methods MiR-106b~ 25 knockout mice were outcrossed into Apolipoprotein E (ApoE) knockout background to generate double knockout mice. At 36 weeks of age, lesion size was evaluated in the aortic sinus by oil-red-O staining. Results Lesion size was 2-fold smaller in double KO mice in comparison to ApoE KO mice. In addition, collagen staining showed a trend towards a stable plaque phenotype in the double KO mice. Lipid profiling of plasma samples of double KO and ApoE KO mice using FPLC revealed over 2-fold decrease in Very low density lipoprotein (VLDL) cholesterol content and a 50% decrease in low density lipoprotein (LDL) cholesterol content in double KO mice. By using target prediction software, we have identified several possible targets for the miR-106b~ 25 cluster including the VLDL and LDL receptors. We found that upon feeding miR-106b~ 25 KO mice with high fat diet, the expression of LDL and VLDL receptors was higher than in the wild-type mice, suggesting the miR-106b~ 25 cluster regulates atherosclerosis by influencing clearance of VLDL and LDL from the plasma. Conclusions We identified the miR-106b~ 25 cluster as a novel regulator of atherosclerosis in ApoE KO mice, presumably by regulating plasma cholesterol levels.

Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate ≥25 mL/min/1.73 m2 and albuminuria (urinary albumin-to-creatinine ratio ≥30 to ≤5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level α = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049.

Background: Chronic kidney disease (CKD) is associated with an increased risk of adverse cardiovascular outcomes, in patients with coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI). However, most studies used bare-metal stents or first-generation drug-eluting stents, and less guideline-directed therapy to reduce cardiovascular risk was reported in CKD patients. This study investigates the impact of moderate-CKD on patients undergoing PCI in the current era. Methods: Patient level data were pooled from 2 multicenter randomized trials (BIONICS and NIREUS trials) with a near “all-comers” design, comparing PCI with ridaforolimus-eluting stents vs. zotarolimus-eluting stents in patients with CAD. Patients were classified according to the presence or absence of moderate-CKD, defined as creatinine clearance (CrCl) Results: 236/2,201 (10.7%) patients had CKD, mean CrCl of 50.3 + 7.8 mL/min. These patients were generally older and more often with hypertension than non-CKD patients, but the use of guideline-directed therapy was similar between the groups. CKD was associated with an increased risk of cardiovascular death (hazard ratio [HR] 6.08; 95% CI 2.11–17.51; p < 0.001), but with a reduced occurrence of repeated revascularization, including ischemia-driven revascularization (HR 0.47; 95% CI 0.24–0.92; p < 0.05). The rate of repeated angiography per severe cardiovascular adverse event was significantly lower in the CKD than the non-CKD group (23/38 [61%] vs. 253/334 [76%], p < 0.05). Conclusions: Moderate-CKD in patients with CAD was associated with higher rates of all-cause and cardiovascular mortality, yet with a lower risk of revascularization 1-year following PCI. Lack of guideline-directed medical therapy does not explain the adverse outcome of CKD patients.

Dialysate purity contributes to the inflammatory response that afflicts hemodialysis patients.To compare the clinical and laboratory effects of using ultrapure water produced by a water treatment system including two reverse osmosis (RO) units in series, with a system that also includes an ultrapure filter (UPF).We performed a retrospective study in 193 hemodialysis patients during two periods: period A (no UPF, 6 months) and period B (same patients, with addition of UPF, 18 months), and a historical cohort of patients treated in the same dialysis unit 2 years earlier, which served as a control group.Mean C-reactive protein, serum albumin and systolic blood pressure worsened in period B compared to period A and in the controls.A double RO system to produce ultrapure water is not inferior to the use of ultrapure filters.

PURPOSE: To report results of renal denervation (RDN) with the first catheter-based, non-balloon occlusion ultrasonic system in patients with resistant hypertension. MATERIALS AND METHODS: In a multicenter, single-arm trial, 39 patients with resistant hypertension (defined as uncontrolled hypertension while taking ≥ 3 antihypertensive medications) were treated. The cohort consisted of 4 groups: severe resistant hypertension (office systolic blood pressure [OSBP] ≥ 160 mm Hg) treated with a unidirectional catheter (group 1; n = 14); severe resistant hypertension treated with a multidirectional catheter (group 2; n = 18); moderate resistant hypertension (OSBP 140-159 mm Hg) treated with a multidirectional catheter (group 3; n = 5); and recurrent severe resistant hypertension, after an initial response to RF RDN (group 4; n = 2). Blood pressure monitoring was performed for 6 months. RESULTS: Severe adverse events were not noted immediately after the procedure or during follow-up. Treatment time was longer withunidirectional than with multidirectional catheters (36.7 min ± 9.6 vs 11.9 min ± 5.8; P < .001). Mean reductions in office blood pressure (systolic/diastolic) at 1, 3, and 6 months were -26.1/-9.6 mm Hg, -28.0/-9.9 mm Hg, and -30.6/-14.1 mm Hg (P < .01 for all). Per-group analysis showed significant OSBP reduction for groups 1 and 2. Patients with isolated systolic hypertension had a significantly smaller reduction in OSBP after 6 months compared with patients with combined systolic/diastolic hypertension (-16.2 mm Hg ± 18.5 vs -9.9 mm Hg ± 33.4; P < .005). CONCLUSIONS: Use of the RDN system was feasible and safe in this phase I study. Significant blood pressure reductions were observed over 6 months, although less in patients with isolated systolic hypertension.

Fall injuries are common among the elderly. The aim of this study was to investigate whether blood-pressure patterns, as measured by 24-h ambulatory blood pressure monitoring (ABPM), or intensification of antihypertensive therapy following the 24-h ABPM, may be associated with fall injuries in hypertensive elderly patients.In a retrospective study, community-based elderly patients (age ≥ 70 years) who were referred to 24-h ABPM were evaluated for fall injuries within one-year post-ABPM. We compared the clinical characteristics, 24-h ABPM patterns and the intensification of hypertensive therapy following 24-h ABPM, between patients with and without a fall injury.Overall 1032 hypertensive elderly patients were evaluated. Fifty-five (5.3%) had a fall injury episode in the year following ABPM. Patients with a fall injury were significantly older, and with higher rates of previous falls. Lower 24-h diastolic blood-pressure (67.3 ± 7.6Low diastolic blood-pressure and increased pulse-pressure in 24-h ABPM were associated with an increased risk of fall injury in elderly hypertensive patients. Intensification of antihypertensive treatment following 24-h ABPM was not associated with an increased risk of fall injury.

Protein drugs are currently delivered by bolus injection and although treatment frequently is successful, these methods also have major drawbacks, which call for the development of alternative technologies allowing prolonged delivery of these drugs. We developed a new ex vivo gene therapy platform called Transduced Autologous Restorative Gene Therapy (TARGT) for sustained long term production and secretion of autologous therapeutic proteins. A biopsy of dermal tissue taken from the patient is transduced ex vivo with a viral vector encoding the required gene under a constitutive promoter. Following measurement of protein secretion ex vivo, the transduced dermal tissue is implanted back into the patient, where it secretes the therapeutic protein into the circulation for several months or longer. A major hurdle to this approach is potential immunogenicity of the transduced tissue following implantation. In this paper we describe the preclinical and early clinical development of this technology, which allowed for overcoming these hurdles. To that end, we have used the helper dependent (HD) adenoviral vector with newly designed expression cassette containing genetic elements to optimize transgene expression. Moreover, we have developed procedures for TARGT tissue implantation, with measures to improve engraftment and reduce inflammation and rejection. Implantation of human TARGT to severe combined immune deficient (SCID) mice indicated long-term production of active proteins in the blood. Preliminary results of a clinical trial from two anemic end-stage renal disease patients, implanted with TARGTs expressing the human erythropoietin (EPO) gene, demonstrated prolonged secretion with physiologic blood level of the hormone and hemoglobin maintenance in the desired range, for a period of at least 5 months without exogenous EPO administration. We believe that the TARGT technology has the potential to become a platform for the sustained delivery of therapeutic proteins in various clinical indications.

Decreased generation of nitric oxide (NO) by endothelial NO synthase (eNOS) characterizes endothelial dysfunction (ECD). Delivery of arginine to eNOS by cationic amino acid transporter-1 (CAT-1) was shown to modulate eNOS activity. We found in female rats, but not in males, that CAT-1 activity is preserved with age and in chronic renal failure, two experimental models of ECD. In contrast, during pregnancy CAT-1 is inhibited. We hypothesize that female sex hormones regulate arginine transport. Arginine uptake in human umbilical vein endothelial cells (HUVEC) was determined following incubation with either 17β-estradiol (E2) or progesterone. Exposure to E2 (50 and 100 nM) for 30 min resulted in a significant increase in arginine transport and reduction in phosphorylated CAT-1 (the inactive form) protein content. This was coupled with a decrease in phosphorylated MAPK/extracellular signal-regulated kinase (ERK) 1/2. Progesterone (1 and 100 pM for 30 min) attenuated arginine uptake and increased phosphorylated CAT-1, phosphorylated protein kinase Cα (PKCα), and phosphorylated ERK1/2 protein content. GO-6976 (PKCα inhibitor) prevented the progesterone-induced decrease in arginine transport. Coincubation with both progesterone and estrogen for 30 min resulted in attenuated arginine transport. While estradiol increases arginine transport and CAT-1 activity through modulation of constitutive signaling transduction pathways involving ERK, progesterone inhibits arginine transport and CAT-1 via both PKCα and ERK1/2 phosphorylation, an effect that predominates over estradiol.

A new protein-delivery platform can provide sustained secretion of recombinant human erythropoietin with the use of small, transduced autologous dermal implants. Study patients with end-stage renal disease were found to have maintenance of stable hemoglobin levels.

Nephrotic syndrome (NS) is divided into steroid-sensitive (SSNS) and -resistant (SRNS) variants. SRNS causes end-stage kidney disease, which cannot be cured. While the disease mechanisms of NS are not well understood, genetic mapping studies suggest a multitude of unknown single-gene causes. We combined homozygosity mapping with whole-exome resequencing and identified an ARHGDIA mutation that causes SRNS. We demonstrated that ARHGDIA is in a complex with RHO GTPases and is prominently expressed in podocytes of rat glomeruli. ARHGDIA mutations (R120X and G173V) from individuals with SRNS abrogated interaction with RHO GTPases and increased active GTP-bound RAC1 and CDC42, but not RHOA, indicating that RAC1 and CDC42 are more relevant to the pathogenesis of this SRNS variant than RHOA. Moreover, the mutations enhanced migration of cultured human podocytes; however, enhanced migration was reversed by treatment with RAC1 inhibitors. The nephrotic phenotype was recapitulated in arhgdia-deficient zebrafish. RAC1 inhibitors were partially effective in ameliorating arhgdia-associated defects. These findings identify a single-gene cause of NS and reveal that RHO GTPase signaling is a pathogenic mediator of SRNS.

Purpose To assess the safety and performance of a nonfocused and nonballooned ultrasonic (US) catheter–based renal sympathetic denervation (RDN) system in normotensive swine. Materials and Methods RDN with the therapeutic intravascular US catheter was evaluated in 3 experiments: ( i ) therapeutic intravascular US RDN vs a control group of untreated animals with follow-up of 30, 45, and 90 days (n = 6; n=12 renal arteries for each group); ( ii ) therapeutic intravascular US RDN vs radiofrequency (RF) RDN in the contralateral artery in the same animal (n = 2; n=4 renal arteries); and ( iii ) therapeutic intravascular US RDN in a recently stent-implanted renal artery (n = 2; n=4 renal arteries). Results In the first experiment, therapeutic intravascular US RDN was safe, without angiographic evidence of dissection or renal artery stenosis. Neuronal tissue vacuolization, nuclei pyknosis, and perineuronal inflammation were evident after RDN, without renal artery wall damage. Norepinephrine levels were significantly lower after therapeutic intravascular US RDN after 30, 45, and 90 days compared with the control group (200.17 pg/mg ± 63.35, 184.75 pg/mg ± 44.51, and 203.43 pg/mg ± 58.54, respectively, vs 342.42 pg/mg ± 79.97). In the second experiment, deeper neuronal ablation penetrance was found with therapeutic intravascular US RDN vs RF RDN (maximal penetrance from endothelium of 7.0 mm vs 3.5 mm, respectively). There was less damage to the artery wall after therapeutic intravascular US RDN than with RF RDN, after which edema and injured endothelium were seen. In the third experiment, denervation inside the stent-implanted segments was feasible without damage to the renal artery wall or stent. Conclusions The therapeutic intravascular US system performed safely and reduced norepinephrine levels. Deeper penetrance and better preservation of vessel wall were observed with therapeutic intravascular US RDN vs RF RDN. Neuronal ablations were observed in stent-implanted renal arteries.

In two siblings of consanguineous parents with intermittent nephrotic-range proteinuria, we identified a homozygous deleterious frameshift mutation in the gene CUBN, which encodes cubulin, using exome capture and massively parallel re-sequencing. The mutation segregated with affected members of this family and was absent from 92 healthy individuals, thereby identifying a recessive mutation in CUBN as the single-gene cause of proteinuria in this sibship. Cubulin mutations cause a hereditary form of megaloblastic anemia secondary to vitamin B(12) deficiency, and proteinuria occurs in 50% of cases since cubilin is coreceptor for both the intestinal vitamin B(12)-intrinsic factor complex and the tubular reabsorption of protein in the proximal tubule. In summary, we report successful use of exome capture and massively parallel re-sequencing to identify a rare, single-gene cause of nephropathy.

Background and objectives: The risk of developing Wilms tumor (WT) can be present or absent in patients with nephrotic syndrome (NS) caused by WT1 mutations. Here, the genotype/phenotype correlation regarding the outcome and risk for WT in 52 patients from 51 families with NS due to WT1 mutations is described. Design, setting, participants, & measurements: This study followed 19 patients with mutations in intron 9 splice donor site (KTS mutations), 27 patients with missense mutations, 4 patients with nonsense mutations, 1 patient with a splice site mutation in intron 8, and 1 patient with a deletion. Results: Twenty-four different WT1 mutations were detected. Sixteen of the 19 patients with KTS mutations were females. These patients had isolated NS if karyotype was 46,XX and Frasier syndrome if karyotype was 46,XY. Patients with KTS mutations presented at a significantly older age and with a slower progression toward chronic kidney disease (CKD) stage 5, compared with missense mutations. Patients with nonsense mutations presented initially with WT. Six patients with missense mutations developed WT after the diagnosis of NS (interval-range from NS onset to WT of 0.1 to 1.4 years). Conclusions: (1) KTS mutations cause isolated NS with absence of WT in 46,XX females. (2) KTS mutations cause Frasier syndrome with gonadoblastoma risk in 46,XY phenotypic females. (3) KTS mutations cause NS with a slower progression when compared with missense mutations. (4) Missense mutations can occur with and without WT. (5) WT1 analysis is important in young patients with NS for early detection and tumor prophylaxis. Clin J Am Soc Nephrol 5: 1655-1662, 2010. doi: 10.2215/CJN.09351209

Background: Elevated phosphorus (P) and calcium (Ca)-P product (Ca × P) are associated with vascular calcification and cardiovascular disease (CVD) morbidity and CVD and all-cause mortality. Objectives: This study examined the effect of sevelamer hydrochloride exposure (regardless of calcium carbonate exposure) on carotid and femoral intima media thickness (IMT), reliable surrogate measures of prospective intimal thickening, in end-stage renal disease patients on maintenance hemodialysis. Methods: The present cross-sectional study is nested in the Sevelamer hydrochloride and ultrasound-measured femoral and carotid intima media thickness progression in end-stage renal disease (SUMMER) clinical trial. Carotid and femoral arteries were visualized in B-mode ultrasonography. Log-transformed IMT was compared by sevelamer hydrochloride exposure and modeled using multiple linear regression. Results: Forty-five subjects were exposed to sevelamer hydrochloride and 130 were not. Exposed subjects had significantly lower carotid IMT, an association which persisted in the multiple linear regression model even after controlling for potentially confounding variables including serum Ca, history of CVD and body weight. Exposed subjects had lower low-density lipoprotein cholesterol levels and significantly higher parathyroid hormone, but no differences in P, Ca and Ca × P. Conclusions: Sevelamer hydrochloride was associated with lower carotid IMT. This association may be mediated through reduction in Ca load, low-density lipoprotein cholesterol lowering or some other pleiotropic effect.

Background. Recessive mutations in the NPHS1 gene encoding nephrin account for ∼40% of infants with congenital nephrotic syndrome (CNS). CNS is defined as steroid-resistant nephrotic syndrome (SRNS) within the first 90days of life. Currently, more than 119 different mutations of NPHS1 have been published affecting most exons. Methods. We here performed mutational analysis of NPHS1 in a worldwide cohort of 67 children from 62 different families with CNS. Results. We found bi-allelic mutations in 36 of the 62 families (58%) confirming in a worldwide cohort that about one-half of CNS is caused by NPHS1 mutations. In 26 families, mutations were homozygous, and in 10, they were compound heterozygous. In an additional nine patients from eight families, only one heterozygous mutation was detected. We detected 37 different mutations. Nineteen of the 37 were novel mutations (∼51.4%), including 11 missense mutations, 4 splice-site mutations, 3 nonsense mutations and 1 small deletion. In an additional patient with later manifestation, we discovered two further novel mutations, including the first one affecting a glycosylation site of nephrin. Conclusions. Our data hereby expand the spectrum of known mutations by 17.6%. Surprisingly, out of the two siblings with the homozygous novel mutation L587R in NPHS1, only one developed nephrotic syndrome before the age of 90days, while the other one did not manifest until the age of 2years. Both siblings also unexpectedly experienced an episode of partial remission upon steroid treatment.

Previous studies in children with focal segmental glomerulosclerosis (FSGS) and nephrotic syndrome (NS) in the USA have revealed inter-ethnic differences in their clinical presentation and outcome. However, ethnicity was based on self-identification rather than on molecular genetic data. Here, we show that genetic heterogeneity exists in self-identified Hispanic (Spanish-American) patients with steroid-resistant nephrotic syndrome (SRNS), as patients may be either of Caucasian or Mesoamerican (Native-American) genetic background. Twenty-one self-identified Hispanic patients with SRNS from 18 families were initially evaluated for mutations in the NPHS2 and WT1 genes. All patients resided and were cared for in the USA. We performed a total genome search for linkage in all Hispanic patients using 250K single nucleotide polymorphism microarrays, comparing Caucasian with Mesoamerican allele frequencies to determine regions of homozygosity by descent and to establish the correct allele frequency for each family. We found that only ten families (56%) of the 18 self-identified Hispanic families are genetically of Mesoamerican descent, whereas the other eight families (44%) are of Caucasian descent. Due to the small number of families examined, we were unable to draw any conclusion on the prevalence of NPHS2 and WT1 in this ethnic group, but the data do suggest that self-identification of ethnicity in Hispanic-American patients is not an adequate basis for genetic studies, as this cohort may represent not only patients of Mesoamerican origin but also patients of Caucasian origin. Thus, one needs to critically review previous studies of FSGS/SRNS patients that involved Hispanic patients as a group. Future larger studies may employ a total genome search for linkage to test self-identified Hispanic ethnicity for true Mesoamerican versus Caucasian ethnicity in order to generate valid genetic data.

Background. Congenital nephrotic syndrome (CNS) is de- fined as nephrotic syndrome that manifests at birth or within the first 3 months of life. Most patients develop end-stage renal disease (ESRD) within 2 to 3 years of life. CNS of the Finnish-type (CNF) features a rather specific renal histology and is caused by recessive mutations in the NPHS1 gene encoding nephrin, a major structural protein of the glomerular slit-diaphragm. So far, more than 80 different mutations of NPHS1 causing CNF have been published. Methods. Here, we performed mutation analysis of NPHS1 by exon sequencing in a worldwide cohort of 32 children with CNS from 29 different families. Results. Sixteen of the 29 families (55%) were found to have two disease-causing alleles in NPHS1. Two additional patients had a single heterozygous mutation in NPHS1. Thirteen of a total of 20 different mutations detected were novel (65%). These were five missense mutations, one nonsense mutation, three deletions, one insertion and three splice-site mutations. Conclusion. Our data expand the spectrum of known NPHS1 mutations by >15% in a worldwide cohort. Surprisingly, two patients with disease-causing mutations showed a relatively mild phenotype, as one patient had a partial remission with steroid treatment and one patient had normal renal function 1 year after the onset of disease. The increased number of known mutations will facilitate future studies into genotype/phenotype correlations.

Background Acute phosphate nephropathy (APN) is a clinicopathological entity causing renal failure, after ingestion of oral sodium phosphate solution (OSPS). Approximately 25 cases have been described, but OSPS is still widely used. This study reports a further 5 cases and discusses the ever-growing significance of APN. Methods Five cases of APN were included, 3 retrospectively whereas 2 were diagnosed prospectively. In all, use of OSPS was established, and other causes of nephrocalcinosis were excluded. Results Average age was 67.4 ± 7.0 years, with a female preponderance (4:1). All patients had hypertension. Baseline serum creatinine: 0.7 to 1.2 mg/dL (creatinine clearance: 52 to 77 mL/min). Time from colonoscopy to presentation was 56 ± 36 days. Serum creatinine levels at presentation: 1.4 to 3.6 mg/dL. Time from colonoscopy to renal biopsy was 123 ± 88 days. Urinalysis showed minimal proteinuria, leucocyturia, and hematuria. One patient had renal glucosuria. All patients were anemic (hemoglobin 8.8–11.4 gr/dL). Serum calcium and phosphate were normal. One required hemodialysis. Mean follow-up was 36 ± 17 months. Serum creatinine levels at end of follow-up were 1.3 to 3.1 mg/dL. Renal function did not recover completely in any patient. Four required long-term erythropoietin treatment. The prominent histopathological findings were calcium–phosphate tubular depositions (100%), interstitial fibrosis (80%), hypertensive changes (80%), and acute tubular degenerative and regenerative changes (60%). Conclusions APN is a serious, irreversible renal complication of OSPS. It is probably under-recognized. Risk factors include female gender, older age, hypertension, and renal failure, although it may occur with preexisting normal renal function.

While a specific role for nitric oxide (NO) in inducing the hemodynamic alterations of pregnancy is somewhat controversial, it is widely accepted that excess NO is generated during pregnancy. l-Arginine is the sole precursor for NO biosynthesis. Among several transporters that mediate l-arginine uptake, cationic amino acid transporter-1 (CAT-1) acts as the specific arginine transporter for endothelial NO synthase. The present study was designed to test the hypothesis that, during pregnancy, when arginine consumption by the fetus is significantly increased, compensatory changes in maternal arginine uptake affect the endothelium. Uptake of radiolabeled arginine (l-[3H]arginine) by freshly harvested maternal aortic rings from pregnant rats decreased by 65 and 30% in mid- and late pregnancy, respectively, compared with those obtained from virgin animals. This decrease was associated with a significant increase in endothelial protein nitration (the footprint of peroxynitrite generation), as shown by both Western blotting and immunohistochemistry utilizing anti-nitrotyrosine antibodies, reflecting endothelial damage. Northern blot analysis revealed that steady-state aortic CAT-1 mRNA levels did not change throughout pregnancy, whereas CAT-1 protein abundance was significantly increased, peaking at mid-pregnancy. Protein content of protein kinase C (PKC)-α, which was previously shown to decrease CAT-1 activity, increased significantly in the pregnant animals and was associated with a significant increase in CAT-1 phosphorylation. Intraperitoneal injection of α-tocopherol, a PKC-α inhibitor, prevented the decrease in arginine transport and attenuated protein nitration. In conclusion, aortic arginine uptake is reduced during pregnancy, through posttranslational modulation of CAT-1 protein, presumably via upregulation of PKC-α. The aforementioned findings are associated with an increase in protein nitration and, therefore, in selected individuals, may lead to the development of certain forms of endothelial dysfunction, like preeclampsia.

Background Phosphate binders are the cornerstone of hyperphosphatemia management in dialysis patients. Ferric citrate is an iron-based oral phosphate binder that effectively lowers serum phosphorus levels. Study Design 52-week, open-label, phase 3, randomized, controlled trial for safety-profile assessment. Setting & Participants Maintenance dialysis patients with serum phosphorus levels ≥6.0mg/dL after washout of prior phosphate binders. Intervention 2:1 randomization to ferric citrate or active control (sevelamer carbonate and/or calcium acetate). Outcomes Changes in mineral bone disease, protein-energy wasting/inflammation, and occurrence of adverse events after 1 year. Measurements Serum calcium, intact parathyroid hormone, phosphorus, aluminum, white blood cell count, percentage of lymphocytes, serum urea nitrogen, and bicarbonate. Results There were 292 participants randomly assigned to ferric citrate, and 149, to active control. Groups were well matched. For mean changes from baseline, phosphorus levels decreased similarly in the ferric citrate and active control groups (−2.04±1.99 [SD] vs −2.18±2.25mg/dL, respectively; P =0.9); serum calcium levels increased similarly in the ferric citrate and active control groups (0.22±0.90 vs 0.31±0.95mg/dL; P =0.2). Hypercalcemia occurred in 4 participants receiving calcium acetate. Parathyroid hormone levels decreased similarly in the ferric citrate and active control groups (−167.1±399.8 vs −152.7±392.1pg/mL; P =0.8). Serum albumin, bicarbonate, serum urea nitrogen, white blood cell count and percentage of lymphocytes, and aluminum values were similar between ferric citrate and active control. Total and low-density lipoprotein cholesterol levels were lower in participants receiving sevelamer than those receiving ferric citrate and calcium acetate. Fewer participants randomly assigned to ferric citrate had serious adverse events compared with active control. Limitations Open-label study, few peritoneal dialysis patients. Conclusions Ferric citrate was associated with similar phosphorus control compared to active control, with similar effects on markers of bone and mineral metabolism in dialysis patients. There was no evidence of protein-energy wasting/inflammation or aluminum toxicity, and fewer participants randomly assigned to ferric citrate had serious adverse events. Ferric citrate is an effective phosphate binder with a safety profile comparable to sevelamer and calcium acetate.

Neurofibromatosis type 1 (NF1) is a common neurocutaneous disease characterized by cafe-au-lait spots, axillary and inguinal freckling, neurofibromas, and optic gliomas. Increased rates of hypertension (HTN) were reported among NF1 patients, however, the prevalence of HTN and pre-HTN in pediatric NF1 patients has not been clarified. Blood pressure (BP) measurements, weight, and renal ultrasound were assessed in 224 NF1 pediatric patients followed in a specialized NF1 clinic. The cohort’s mean age was 9.1 ± 4.1 years. Overweight and obesity were found in 12.9 and 10.3 % of them, respectively. BP was measured averagely 2.9 times per patient on different occasions. Blood pressure was in the pre-HTN and HTN ranges in 14.9 and 16.9 % of measurements, respectively. BP >95th was detected in 20.5 % at the first measurement. Of 114 children with at least three BP measurements, 18.4 % had two values in the HTN range and 6.14 % had at least three. Overweight was not associated with HTN among children with NF1. Urinary tract ultrasonographic abnormalities were detected in 6.8 % (11/161) of cases. The prevalence of increased BP in pediatric NF1 is much higher than in the general pediatric population. BP has to be regularly assessed and managed in this high-risk population.

It has become evident that increased nitric oxide (NO) generation may be associated with production of reactive oxygen species, such as peroxynitrite (ONOO-). Peroxynitrite has been postulated to be responsible for several of the cytotoxic effects previously ascribed to NO. Since cellular arginine uptake has been shown to modulate nitric oxide synthase activity, we were intrigued to study the effect of ONOO- on arginine traffic in renal mesangial cells.Arginine uptake, CAT-1 and CAT-2 mRNA expression by northern blotting analysis, and CAT-1 protein content using western blotting were determined in mesangial cells pre-treated with peroxynitrite (0.1 and 0.5 mM) for 2 h.Peroxynitrite induced a significant increase in arginine uptake and CAT-2 mRNA expression compared with untreated cells. In contrast, CAT-1 mRNA expression and protein abundance were diminished.In rat mesangial cells, peroxynitrite augments arginine uptake via augmentation of CAT-2 while decreasing CAT-1 expression.

Endothelial cell dysfunction (ECD) is a common feature of chronic renal failure (CRF). Defective nitric oxide (NO) generation due to decreased endothelial NO synthase (eNOS) activity is a crucial parameter characterizing ECD. L-arginine is the sole precursor for NO biosynthesis. Among several transporters that mediate L-arginine uptake, cationic amino-acid transporter-1 (CAT-1) acts as the specific arginine transporter for eNOS. Our hypothesis implies that CAT-1 is a major determinant of eNOS activity in CRF. We studied glomerular and aortic arginine uptake, CAT-1, and CAT-2 messenger ribonucleic acid (mRNA) expression, and CAT-1 protein in: (a) rats 6 weeks following 5/6 nephrectomy (CRF), (b) sham-operated animals, and (c) rats with CRF treated orally with either atorvastatin or arginine in drinking water (modalities which have been shown to enhance eNOS activity and improve endothelial function). Both glomerular and aortic arginine transport were significantly decreased in CRF. Treatment with either arginine or atorvastatin abolished the decrease in arginine uptake in CRF rats. Using reverse transcriptase-polymerase chain reaction and Northern blotting, we found a significant increase in glomerular and aortic CAT-1 mRNA expression in CRF. Western blotting revealed that CAT-1 protein was decreased in CRF, but remained intact following arginine and atorvastatin administration. Renal and systemic arginine uptake is attenuated in CRF, through modulation of CAT-1 protein. These findings provide a possible novel mechanism to eNOS inactivation and endothelial dysfunction in uremia.

Podocin mutations (NPHS2gene) are mostly responsible for steroid-resistant nephrotic syndrome (SRNS) of childhood onset. Patients withNPHS2gene mutations do not respond to corticoids and other immunosuppressive agents; partial remission can be rarely induced by cyclosporin A. We present a boy, where SRNS was diagnosed within first year of life. By the age of 15 years, proteinuria reached 9000 mg/24 h, cholesterolemia 15 mmol/L, albuminemia 19.6 g/L, in spite of combined therapy with cyclosporine A, methylprednisolone, enalapril and losartan. At that time a combined heterozygous form of twoNPHS2gene mutations (p.R138Q and p.V290M) was diagnosed, methylprednisolone was discontinued and patient underwent ten plasmapheresis procedures. This resulted in clinical improvement (proteinuria 3000 mg/24 h, S-cholesterol 6 mmol/L, albumin 30g/L) lasting for three years. In conclusion, plasmapheresis can result in clinical improvement and stabilization of SRNS caused by podocine mutation, before renal replacement therapy is initiated.

Wilms' tumour suppressor gene 1 (WT1) encodes a transcription factor required for normal development of the genitourinary system. In the kidney, mutations in WT1 can cause diffuse mesangial sclerosis or focal segmental glomerulosclerosis. Here, we report on a girl with a mutation in WT1, who developed membranoproliferative glomerulonephritis (MPGN) 3 years after completion of treatment for Wilms' tumour. This finding extends the spectrum of glomerular disease seen with WT1 mutations and could have implications for the screening of children with MPGN.

There is a striking resemblance between this and a leitmotif that runs through many medical conditionsiron deficiency (ID). It may cause different signs and symptoms in different people [1,2], including anemia, weakness, frailty, headache, irritability, shortness of breath, tiredness, reduced exercise tolerance, a tendency to fall, lack of cognitive function, restless legs syndrome, depression, worsening of Quality of Life and increased hospitalizations and morbidity. And it may worsen Congestive Heart Failure (CHF) [3-6]. It may also present with or without anemia.

Endothelial cell dysfunction (ECD) is a common feature of chronic renal failure (CRF). Defective nitric oxide (NO) generation due to decreased endothelial nitric oxide synthase (eNOS) activity is a crucial parameter characterizing ECD. Decreased activity of cationic amino acid transporter-1 (CAT-1), the selective arginine transporter of eNOS, has been shown to inhibit eNOS in uremia. Recently, we failed to demonstrate a decrease in glomerular arginine transport in uremic female rats (Schwartz IF, Grupper A, Soetendorp H, Hillel O, Laron I, Chernichovski T, Ingbir M, Shtabski A, Weinstein T, Chernin G, Shashar M, Hershkoviz R, Schwartz D. Am J Physiol Renal Physiol 303: F396–F404, 2012). The current experiments were designed to determine whether sexual dimorphism which characterizes glomerular arginine transport system in uremia involves the systemic vasculature as well and to assess the effect of l-arginine in such conditions. Contractile and vasodilatory responses, ultrastructural changes, and measures of the l-arginine-NO system were performed in thoracic aortas of female rats subjected to ⅚ nephrectomy. The contractile response to KCl was significantly reduced, and acetylcholine-induced vasodilation was significantly impaired in aortas from CRF dames compared with healthy rats. Both of these findings were prevented by the administration of arginine in the drinking water. The decrease in both cGMP generation, a measure of eNOS activity, and aortic eNOS and phosphorylated eNOS abundance observed in CRF rats was completely abolished by l-arginine, while arginine transport and CAT-1 protein were unchanged in all experimental groups. Arginine decreased both serum levels of advanced glycation end products and the asymmetrical dimethylarginine/arginine ratio and restored the endothelial ultrastructure in CRF rats. In conclusion. arginine administration has a profound beneficial effect on ECD, independently of cellular arginine uptake, in CRF female rats.

Background C-reactive protein (CRP) is a recognized marker of systemic inflammation. Its association with carotid and femoral intima media thickness (surrogate measures of atherosclerosis) may explain excess cardiovascular disease risk in hemodialysis patients. Objectives To estimate the association between CRP and both carotid and femoral IMT in hemodialysis (HD) patients; to predict CRP in these patients. Methods The present cross-sectional study is nested in the Sevelamer hydrochloride and ultrasound-measured femoral and carotid intima media thickness progression in end-stage renal disease (SUMMER) clinical trial. Carotid (common, internal, and bifurcation) and femoral arteries were visualized in B-mode ultrasonography. CRP was measured in serum. Results The study cohort included 144 HD patients (39.5% female, mean age 67.8 ± 11.5 years). All measures of both carotid and femoral IMT were significantly positively associated with CRP. Subjects with a history of smoking or coronary revascularization had significantly higher CRP levels, while subjects treated with sevelamer hydrochloride had significantly lower CRP. CRP was significantly positively associated with serum phosphorus, calcium, alkaline phosphatase, and PTH, and significantly inversely associated with HDL and albumin. Conclusions CRP is significantly positively associated with both femoral and carotid IMT. Treatment with sevelamer hydrochloride is associated with lower CRP in HD patients.

Background: The spectrum of cardiovascular toxicity by cyclosporine (CsA) includes hypertension, accelerated atherosclerosis, and thrombotic microangiopathy, all of which are the result of endothelial cell dysfunction. Endothelial cell dysfunction is characterized by decreased endothelial nitric oxide synthase (eNOS) activity. Cationic amino acid transporter-1 (CAT-1) is the specific arginine transporter for eNOS. CsA has been shown to attenuate nitric oxide (NO) generation. However, the mechanism remains elusive. We hypothesize that CsA inhibits eNOS activity through modulation of its selective arginine supplier CAT-1. Methods: We studied the effect of CsA on arginine uptake, NO2/NO3 generation, and CAT-1, protein kinase Cα (PKCα), and phosphorylated PKCα protein expression in human umbilical vein endothelial cell cultures (HUVEC) in the absence and presence of L-arginine. Results: CsA (0.5-2 μg/ml) significantly attenuated arginine transport in a dose- and time-dependent manner, a phenomenon which was prevented by co-incubation with L-arginine (1 mM). The aforementioned findings were accompanied by increased protein nitration, a measure for peroxynitrite accumulation. In contrast, no changes were observed in NO2/NO3 generation. CsA significantly decreased the abundance of CAT-1 protein, an effect that was attenuated by L-arginine. PKCα and phosphorylated PKCα (CAT-1 inhibitors) protein contents were not affected by CsA. Conclusion: CsA inhibits arginine transport and induces protein nitration in HUVEC through modulation of CAT-1.

Pregnancy worsens renal function in females with chronic renal failure (CRF) through an unknown mechanism. Reduced nitric oxide (NO) generation induces renal injury. Arginine transport by cationic amino acid transporter-1 (CAT-1), which governs endothelial NO generation, is reduced in both renal failure and pregnancy. We hypothesize that attenuated maternal glomerular arginine transport promotes renal damage in CRF pregnant rats. In uremic rats, pregnancy induced a significant decrease in glomerular arginine transport and cGMP generation (a measure of NO production) compared with CRF or pregnancy alone and these effects were prevented by l-arginine. While CAT-1 abundance was unchanged in all experimental groups, protein kinase C (PKC)-α, phosphorylated PKC-α (CAT-1 inhibitor), and phosphorylated CAT-1 were significantly augmented in CRF, pregnant, and pregnant CRF animals; phenomena that were prevented by coadministrating l-arginine. α-Tocopherol (PKC inhibitor) significantly increased arginine transport in both pregnant and CRF pregnant rats, effects that were attenuated by ex vivo incubation of glomeruli with PMA (a PKC stimulant). Renal histology revealed no differences between all experimental groups. Inulin and p-aminohippurate clearances failed to augment and renal cortical expression of hypoxia inducible factor-1α (HIF-1α) significantly increased in CRF pregnant rat, findings that were prevented by arginine. These studies suggest that in CRF rats, pregnancy induces a profound decrease in glomerular arginine transport, through posttranslational regulation of CAT-1 by PKC-α, resulting in attenuated NO generation. These events provoke renal damage manifested by upregulation of renal HIF-1α and loss of the ability to increase glomerular filtration rate during gestation.

BACKGROUND: Hyperkalemia, induced by renin‐angiotensin‐aldosterone system inhibition (RAAS‐I) in patients with chronic kidney disease (CKD), or cardiac disease often leads to withdrawal of RAAS‐I therapy. Sodium polystyrene sulfonate (SPS) is a potassium‐binding resin used for the treatment of hyperkalemia. Recently, concerns about the safety and efficacy of SPS were raised. We report here a follow‐up of 14 patients with CKD and heart disease on RAAS‐I treatment who were treated with low‐dose daily SPS to prevent recurrence of hyperkalemia. HYPOTHESIS: Daily SPS is safe and effective for secondary prevention of hyperkalemia induced by RAAS‐I therapy in CKD patients with heart disease. METHODS: We reviewed the medical charts of the patients with CKD (nondialysis patients) and heart disease treated in our CKD clinic from 2005 to 2010 and identified all patients on RAAS‐I therapy who were treated with daily SPS (sorbitol‐free) after episodes of hyperkalemia. Data on hospitalizations, symptoms that may be attributed to SPS therapy, and electrolyte concentration levels were obtained. RESULTS: Fourteen patients were treated with low‐dose SPS therapy for a total of 289 months (median length of follow‐up, 14.5 months). None of the patients developed colonic necrosis or life‐threatening events that could be attributed to SPS use. Mild hypokalemia was noted in 2 patients and responded to reducing the dose of SPS. No further episodes of hyperkalemia were recorded while patients were on the therapy. SPS was well‐tolerated during the follow‐up without need for withdrawal or reduction of the dose of RAAS‐I therapy by any patients. CONCLUSIONS: Low‐dose SPS was safe and effective as a secondary preventive measure for hyperkalemia induced by RAAS‐I in CKD patients with heart disease. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.

WOS: 000290246800035, PubMed ID: 21540551, Steroid-resistant nephrotic syndrome (SRNS) is a frequent cause of end-stage renal failure. Identification of single-gene causes of SRNS has generated some insights into its pathogenesis; however, additional genes and disease mechanisms remain obscure, and SRNS continues to be treatment refractory. Here we have identified 6 different mutations in coenzyme Q(10) biosynthesis monooxygenase 6 (COQ6) in 13 individuals from 7 families by homozygosity mapping. Each mutation was linked to early-onset SRNS with sensorineural deafness. The deleterious effects of these human COQ6 mutations were validated by their lack of complementation in coq6-deficient yeast. Furthermore, knockdown of Coq6 in podocyte cell lines and coq6 in zebrafish embryos caused apoptosis that was partially reversed by coenzyme Q(10) treatment. In rats, COQ6 was located within cell processes and the Golgi apparatus of renal glomerular podocytes and in stria vascularis cells of the inner ear, consistent with an oto-renal disease phenotype. These data suggest that coenzyme Q(10)-related forms of SRNS and hearing loss can be molecularly identified and potentially treated., NIHUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USA [DK076683, DK086542, GM45952, DK46073, P30 DK081943]; KMD Foundation; Thrasher Research Fund; German Research Foundation (DFG)German Research Foundation (DFG) [SFB 423, TP B19]; German Federal Ministry of Science and Education through the National Genome Research Network; European CommunityEuropean Community (EC) [EUNEFRON 201590]; Fondazione CARIPARO Telethon ItalyFondazione Telethon [GGP09207]; Spanish FIS [PI080500]; Neph-Cure Foundation; American Heart AssociationAmerican Heart Association, We thank the affected individuals and their families for participation. We thank Corina Nailescu for contribution of clinical data. This research was supported by grants from the NIH to F. Hildebrandt (DK076683 and DK086542), C.F. Clarke (GM45952), and R.C. Wiggins (DK46073 and P30 DK081943) and by a grant from the KMD Foundation and the Thrasher Research Fund to F. Hildebrandt. F. Hildebrandt is an Investigator of the Howard Hughes Medical Institute, a Doris Duke Distinguished Clinical Scientist, and the Frederick G.L. Huetwell Professor. H. Prokisch was supported by the Impulse and Networking Fund of the Helmholtz Association in the framework of the Helmholtz Alliance for Mental Health in an Ageing Society (HA-215), by the German Network for Mitochondria] Disorders (mitoNET 01GM0862 and 01GM0867), and by Systems Biology of Metabotypes (SysMBo 0315494A): The work was further supported by a grant from the German Research Foundation (DFG, SFB 423, TP B19) to M. Zenker, by the German Federal Ministry of Science and Education through the National Genome Research Network to G. Nurnberg and P. Nurnberg, by the European Community FP7 program (EUNEFRON 201590) to D. Muller, by Fondazione CARIPARO Telethon Italy (GGP09207) to L. Salviati, by a Spanish FIS grant (PI080500) to P. Navas, and by the Young Investigator Career Development Grant from the Neph-Cure Foundation and the National Scientist Development Grant from the American Heart Association to C. Paul.

Steroid-resistant focal segmental glomerulosclerosis (FSGS) often recurs after renal transplantation. In this international survey, we sought to identify genotype-phenotype correlations of recurrent FSGS. We surveyed 83 patients with childhood-onset primary FSGS who received at least one renal allograft and analyzed 53 of these patients for NPHS2 mutations. The mean age at diagnosis was 6.7 years, and the mean age at first renal transplantation was 13 years. FSGS recurred in 30 patients (36%) after a median of 13 days (range, 1.5 to 152 days). Twenty-three patients received a second kidney transplant, and FSGS recurred in 11 (48%) after a median of 16 days (range, 2.7 to 66 days). None of the 11 patients with homozygous or compound heterozygous NPHS2 mutations developed recurrent FSGS compared with 45% of patients without mutations. These data suggest that genetic testing for pathogenic mutations may be important for prognosis and treatment of FSGS both before and after transplantation.