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Familial cold autoinflammatory syndrome, Muckle-Wells syndrome (MWS), and chronic, infantile, neurological, cutaneous and articular (CINCA) syndrome are dominantly inherited autoinflammatory diseases associated to gain-of-function NLRP3 mutations and included in the cryopyrin-associated periodic syndromes (CAPS). A variable degree of somatic NLRP3 mosaicism has been detected in approximate to 35% of patients with CINCA. However, no data are currently available regarding the relevance of this mechanism in other CAPS phenotypes. Objective To evaluate somatic NLRP3 mosaicism as the disease-causing mechanism in patients with clinical CAPS phenotypes other than CINCA and NLRP3 mutation-negative. Methods NLRP3 analyses were performed by Sanger sequencing and by massively parallel sequencing. Apoptosis-associated Speck-like protein containing a CARD (ASC)-dependent nuclear factor kappa-light chain-enhancer of activated B cells (NF-kappa B) activation and transfection-induced THP-1 cell death assays determined the functional consequences of the detected variants. Results A variable degree (5.5-34.9%) of somatic NLRP3 mosaicism was detected in 12.5% of enrolled patients, all of them with a MWS phenotype. Six different missense variants, three novel (p.D303A, p.K355T and p.L411F), were identified. Bioinformatics and functional analyses confirmed that they were disease-causing, gain-of-function NLRP3 mutations. All patients treated with anti-interleukin1 drugs showed long-lasting positive responses. Conclusions We herein show somatic NLRP3 mosaicism underlying MWS, probably representing a shared genetic mechanism in CAPS not restricted to CINCA syndrome. The data here described allowed definitive diagnoses of these patients, which had serious implications for gaining access to anti-interleukin 1 treatments under legal indication and for genetic counselling. The detection of somatic mosaicism is difficult when using conventional methods. Potential candidates should benefit from the use of modern genetic tools.

Producción Científica, There is notable heterogeneity in the implementation of cytomegalovirus (CMV) prevention practices among CMV-seropositive (R+) kidney transplant (KT) recipients. In this prospective observational study, we included 387 CMV R+ KT recipients from 25 Spanish centers. Prevention strategies (antiviral prophylaxis or preemptive therapy) were applied according to institutional protocols at each site. The impact on the 12-month incidence of CMV disease was assessed by Cox regression. Asymptomatic CMV infection, acute rejection, graft function, non-CMV infection, graft loss, and all-cause mortality were also analyzed (secondary outcomes). Models were adjusted for a propensity score (PS) analysis for receiving antiviral prophylaxis. Overall, 190 patients (49.1%) received preemptive therapy, 185 (47.8%) antiviral prophylaxis, and 12 (3.1%) no specific intervention. Twelve-month cumulative incidences of CMV disease and asymptomatic infection were 3.6% and 39.3%, respectively. Patients on prophylaxis had lower incidence of CMV disease [PS-adjusted HR (aHR): 0.10; 95% confidence interval (CI): 0.01–0.79] and asymptomatic infection (aHR: 0.46; 95% CI: 0.29–0.72) than those managed preemptively, with no significant differences according to the duration of prophylaxis. All cases of CMV disease in the prophylaxis group occurred after prophylaxis discontinuation. There were no differences in any of the secondary outcomes. In conclusion, antiviral prophylaxis was associated with a lower occurrence of CMV disease in CMV R+ KT recipients, although such benefit should be balanced with the risk of late-onset disease.

SummaryMitochondrial diseases include a group of maternally inherited genetic disorders caused by mutations in mtDNA. In most of these patients, mutated mtDNA coexists with wild-type mtDNA, a situation known as mtDNA heteroplasmy. Here, we report on a strategy toward preventing germline transmission of mitochondrial diseases by inducing mtDNA heteroplasmy shift through the selective elimination of mutated mtDNA. As a proof of concept, we took advantage of NZB/BALB heteroplasmic mice, which contain two mtDNA haplotypes, BALB and NZB, and selectively prevented their germline transmission using either mitochondria-targeted restriction endonucleases or TALENs. In addition, we successfully reduced human mutated mtDNA levels responsible for Leber’s hereditary optic neuropathy (LHOND), and neurogenic muscle weakness, ataxia, and retinitis pigmentosa (NARP), in mammalian oocytes using mitochondria-targeted TALEN (mito-TALENs). Our approaches represent a potential therapeutic avenue for preventing the transgenerational transmission of human mitochondrial diseases caused by mutations in mtDNA.PaperClip

27 p.-7 fig.-7 tab. Campistol, Josep M. et al., [EN]Haemolytic uraemic syndrome (HUS) is a clinical entity defined as the triad of nonimmune haemolytic anaemia, thrombocytopenia, and acute renal failure, in which the underlying lesions are mediated by systemic thrombotic microangiopathy (TMA). Different causes can induce the TMA process that characterises HUS. In this document we consider atypical HUS (aHUS) a sub-type of HUS in which the TMA phenomena are the consequence of the endotelial damage in the microvasculature of the kidneys and other organs due to a disregulation of the activity of the complement system. In recent years, a variety of aHUs-related mutations have been identified in genes of the complement system, which can explain approximately 60% of the aHUS cases, and a number of mutations and polymorphisms have been functionally characterised. These findings have stablished that aHUS is a consequence of the insufficient regulation of the activation of the complement on cell surfaces, leading to endotelial damage mediated by C5 and the complement terminal pathway. Eculizumab is a monoclonal antibody that inhibits the activation of C5 and blocks the generation of the pro-inflammatory molecule C5a and the formation of the cell membrane attack complex. In prospective studies in patients with aHUS, the use of Eculizumab has shown a fast and sustained interruption of the TMA process and it has been associated with significative long-term improvements in renal function, the interruption of plasma therapy and important reductions in the need of dialysis. According to the existing literature and the accumulated clinical experience, the Spanish aHUS Group published a consensus document with recommendations for the treatment of aHUs (Nefrologia 2013;33[1]:27–45). In the current online version of this document, we update the aetiological classification of TMAs, the pathophysiology of aHUS, its differential diagnosis and its therapeutic management., [ES]El síndrome hemolítico urémico (SHU) es una entidad clínica definida por la tríada anemia hemolítica no inmune, trombocitopenia e insuficiencia renal aguda, en la que las lesiones subyacentes están mediadas por un proceso de microangiopatía trombótica (MAT) sistémico. Distintas causas pueden desencadenar el proceso de MAT que caracteriza el SHU. En este documento consideramos SHU atípico (SHUa) como el subtipo de SHU en el que los fenómenos de MAT son fundamentalmente consecuencia del daño producido en el endotelio de la microvasculatura renal y de otros órganos por desregulación de la actividad del sistema del complemento. En los últimos años se han identificado diversas mutaciones en genes del sistema del complemento asociados a SHUa, que explicarían aproximadamente el 60% de los casos de SHUa, y se han caracterizado funcionalmente numerosas mutaciones y polimorfismos asociados a SHUa que han permitido determinar que la patología se produce como consecuencia de la deficiente regulación de la activación del complemento sobre las superficies celulares y que lleva al daño endotelial mediado por la activación del C5 y de la vía terminal del complemento. Eculizumab es un anticuerpo monoclonal humanizado que inhibe la activación del C5, bloqueando la generación de la molécula proinflamatoria C5a y la formación del complejo de ataque de membrana. En estudios prospectivos en pacientes con SHUa su administración ha demostrado la interrupción rápida y sostenida del proceso de MAT, con una mejora significativa de la función renal a largo plazo y una reducción importante de la necesidad de diálisis y el cese de la terapia plasmática. En función de las evidencias científicas publicadas y la experiencia clínica acumulada, el Grupo Español de SHUa publicamos un documento de consenso con recomendaciones para el tratamiento de la enfermedad (Nefrología 2013;33(1):27–45). En la presente versión online del documento se actualizan los contenidos sobre la clasificación etiológica de las MAT, la fisiopatología del SHUa, su diagnóstico diferencial y su manejo terapéutico., Research carried out by Dr. Rodríguez de Córdoba has been funded by the Ministry of Economy and Competitiveness (SAF2011-26583), the Community of Madrid (S2010/BMD2316),the European Union (EURenOmics), the Fundación Renal Ínigo Álvarez de Toledo, and the CIBER of rare diseases.

Conversion from calcineurin inhibitor to sirolimus, rapamycin has become an option in patients with chronic allograft dysfunction (CAD). However, in many cases an increase of proteinuria has been observed. The aim was to characterize the course of this so far unexplained proteinuria after conversion.In 149 renal transplant patients from various Spanish centres, proteinuria and renal function were analysed 6 months before until 6 months after conversion. Patients were divided into three groups according to mean proteinuria before conversion (1:or=300 mg/day; 2:300-3500 mg/day; 3:3.5 g/day).Generally patients showed an increase of proteinuria from 864+/-1441 (0-12125) to 1541+/-1878 (0-10976) mg/day after conversion; P0.001. Group 1: 145+/-92 vs 669+/-868 mg/day, P0.001; group 2: 1041+/-799 vs 1995+/-2021 mg/day, P0.001; group 3: 6205+/-3184 vs 4859+/-2122 mg/day, P=NS. Patients with an increase of proteinuria of500 mg/day (n=60; 40%) had a higher serum creatinine before conversion compared with patients with no or moderate increase (2.5+/-0.8 vs 2.15+/-0.72 mg/dl; P=0.002). The group that experienced an increase500 mg/day had a higher serum creatinine after conversion compared with the patients with no or moderate increase (2.8+/-1.0 vs 2.1+/-1.2; P0.001). Of 64 patients, 19 in group 1 showed an increase500 mg/day.Conversion for CAD can be associated with an increase of proteinuria in patients with pre-existing renal damage; however, it preserves renal function in patients with better creatinine and proteinuria before conversion, and might not be of benefit if advanced loss of renal function and high proteinuria are already present before conversion.

The efficacy and tolerability of everolimus have been demonstrated in a number of clinical trials, and there is also an increasing body of clinical experience. The efficacy of everolimus after renal transplantation is at least equivalent to that of mycophenolate mofetil. Studies combining everolimus with full- or reduced-dose cyclosporine (CsA) have shown that CsA exposure can be minimized, without increasing the risk of acute rejection, particularly when combined with therapeutic drug monitoring. A role for everolimus in regimens involving elimination of calcineurin inhibitors is currently being investigated. Everolimus with significantly reduced-dose CsA has not been shown to enhance CsA-related nephrotoxicity. Adverse events seen in trials of everolimus are generally class-specific and include edema, arthralgia, dyslipidemia, impaired wound healing, and proteinuria. A low incidence of malignancy has been observed with everolimus, and studies are ongoing to examine its antitumor effects in the treatment of certain malignancies. It seems likely that everolimus will continue to play a role in the development of reduced-exposure calcineurin inhibitor regimens and has considerable potential to improve outcomes for transplant recipients, focused perhaps on "old-for-old" transplant recipients and patients at high risk of poor graft function or malignancy. This review considers the available data on the clinical application of everolimus and identifies current and future strategies for improving outcomes after renal transplantation.

BACKGROUND The study was conducted in order to describe possible intraglomerular haemodynamic changes inducing proteinuria after 14 patients with chronic allograft dysfunction were converted from calcineurin inhibitors (CIs) to sirolimus without changing concomitant immunosuppression or antihypertensive treatment. METHODS Creatinine, glomerular filtration rate (GFR), proteinuria, renal functional reserve (RFR) and effective renal plasma flow (ERPF) were determined before and 8 months after conversion. Intraglomerular pressure (P(G)), afferent arteriolar resistance (AAR) and efferent arteriolar resistance (EAR) were calculated using Gomez's formula. RESULTS Creatinine (1.97 vs 2.075 mg/dl; P = 0.270) and GFR (40 vs 43 ml/min; P = 0.505) remained unchanged, proteinuria increased (338 vs 1146 mg/24 h; P = 0.006), RFR decreased (34.84 vs 13.47%; P = 0.019), ERPF (248 vs 310.6 ml/min; P = 0.0625) and P(G) (42.72 vs 46.17 mmHg; P = 0.0625) tendentially increased and AAR tendentially decreased (14.12 vs 10.28 dyne/s/cm(5); P = 0.0625). CONCLUSION After conversion, P(G) shows a tendency to increase and RFR decreases significantly-characteristics of hyperfiltration, which could possibly partially explain the increase of proteinuria. Therefore, the application of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers seems promising. To avoid hyperfiltration, conversion should be performed early when renal insufficiency is still moderate.

Background/Aims: Chronic allograft nephropathy is the main cause of late graft loss and nonimmunological factors, including hypertension and proteinuria, the principal etiological factors. In this context, blockage of the renin-angiotensin system could be helpful. The aim of the present study was to review the renoprotective efficacy of losartan in a large group of renal transplant patients undergoing long-term follow-up. Methods: A retrospective analysis of 276 renal transplant patients treated with losartan was performed. The indication for losartan was arterial hypertension in 163 patients, proteinuria in 37 patients and hypertension plus proteinuria in the remaining 76 patients. Clinical and biochemical parameters before starting losartan treatment (–6 months, –3 months and at baseline) and 3, 6, 9, 12, 18 and 24 months after the introduction of losartan were analyzed. Results: Arterial hypertension significantly decreased after the introduction of losartan (p = 0.000). Serum creatinine was significantly decreased by losartan therapy, and changes in the serum creatinine slope (1/sCr) before and after losartan were statistically significant. Proteinuria markedly decreased after the introduction of losartan. Clinical and biochemical tolerance of losartan was excellent in most patients and only 9 out of the 276 patients (3%) treated with losartan discontinued the drug because of an adverse event. During follow-up, only 3 patients required substitutive treatment with dialysis due to progressive deterioration of renal function in the context of chronic allograft nephropathy. Conclusion: Losartan demonstrated high efficacy as a renoprotective agent in renal transplant patients and could be useful in the treatment and prevention of chronic allograft nephropathy.

BACKGROUND Our aim was to study time-dependent modifications in the characteristics of renal transplants in Spain during the 1990s and risk factors associated with death-censored graft failure after the first year. METHODS A total of 3,365 adult patients who underwent transplantation in 1990, 1994, and 1998 with a functioning graft after the first year were included. RESULTS Ten-year patient and graft survival rates were 82% and 70%. Major modifications between 1990 and 1998 were increases in donor age (32 +/- 15 to 43 +/- 18 years, P

Objective To investigate the prevalence of tumor necrosis factor receptor–associated periodic syndrome (TRAPS) among outpatients presenting with recurrent fevers and clinical features consistent with TRAPS. Methods Mutational screening was performed in affected members of 18 families in which multiple members had symptoms compatible with TRAPS and in 176 consecutive subjects with sporadic (nonfamilial) “TRAPS-like” symptoms. Plasma concentrations of soluble tumor necrosis factor receptor superfamily 1A (sTNFRSF1A) were measured, and fluorescence-activated cell sorter analysis was used to measure TNFRSF1A shedding from monocytes. Results Eight novel and 3 previously reported TNFRSF1A missense mutations were identified, including an amino acid deletion (ΔD42) in a Northern Irish family and a C70S mutation in a Japanese family, both reported for the first time. Only 3 TNFRSF1A variants were found in patients with sporadic TRAPS (4 of 176 patients). Evidence for nonallelic heterogeneity in TRAPS-like conditions was found: 3 members of the “prototype familial Hibernian fever” family did not possess C33Y, present in 9 other affected members. Plasma sTNFRSF1A levels were low in TRAPS patients in whom renal amyloidosis had not developed, but also in mutation-negative symptomatic subjects in 4 families, and in 14 patients (8%) with sporadic TRAPS. Reduced shedding of TNFRSF1A from monocytes was demonstrated in vitro in patients with the T50M and T50K variants, but not in those with other variants. Conclusion The presence of TNFRSF1A shedding defects and low sTNFRSF1A levels in 3 families without a TNFRSF1A mutation indicates that the genetic basis among patients with “TRAPS-like” features is heterogeneous. TNFRSF1A mutations are not commonly associated with nonfamilial recurrent fevers of unknown etiology.

Transforming growth factor-beta1 (TGF-beta1) is a cytokine that plays a key role in the development of idiopathic pulmonary fibrosis. There have been reports on the presence of two genetic polymorphisms in the DNA sequence encoding the leader sequence of the TGF-beta1 protein, located in codons 10 and 25. The objective of this study was to investigate the association between TGF-beta1 gene polymorphisms in codons 10 and 25 and the susceptibility to idiopathic pulmonary fibrosis and the progression of the disease. Compared with healthy control subjects (n = 140), patients with idiopathic pulmonary fibrosis (n = 128) showed no significant deviations in genotype or allele frequencies. One hundred and ten patients with idiopathic pulmonary fibrosis were followed up for 30.3 +/- 25 months. The presence of a proline allele at codon 10 was independently associated with a significant increase in alveolar arterial oxygen tension difference during follow-up, after controlling for the effect of treatment (coefficient = 0.59; 95% confidence intervals, 0.23 to 0.96; p = 0.002). These findings suggest that (1) TGF-beta1 gene polymorphisms in codons 10 and 25 do not predispose to the development of idiopathic pulmonary fibrosis; and (2) TGF-beta1 gene polymorphisms may affect disease progression in patients with idiopathic pulmonary fibrosis.

Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurring short attacks of fever and serositis. Secondary AA amyloidosis is the worst complication of the disease and often determines the prognosis. The MEFV gene, on chromosome 16p13.3, is responsible for the disease and around 30 mutations have been reported to date. Colchicine is the standard FMF treatment today, and prevents both attacks and amyloid deposition in 95% of patients. Here we describe a three-generation Spanish kindred with five family members affected by a severe periodic inflammatory disorder associated with renal AA amyloidosis and colchicine unresponsiveness. Clinical diagnosis of definite FMF disease was made based on the Tel-Hashomer criteria set. Genetic analyses revealed that all subjects were heterozygous for the new H478Y MEFV variant, segregating with the disease. In addition, mutations in the TNFRSF1A and CIAS1/PYPAF1/NALP3 genes, related to the dominantly inherited autoinflammatory periodic syndromes, were ruled out. However, the dominant inheritance of the disease, the long fever episodes with a predominant joint involvement, and the resistance to colchicine in these patients raise the question of whether the periodic syndrome seen in this kindred is a true FMF disease with unusual manifestations or rather another MEFV-associated periodic syndrome. We conclude that the new H478Y MEFV mutation is the dominant pathological variant causing the inflammatory periodic syndrome in this kindred and that full-length analyses of the MEFV gene are needed to obtain an adequate diagnosis of patients with clinical suspicion of a hereditary periodic fever syndrome, especially those from non-ancestral populations.

Haemolytic–uraemic syndrome is a clinical syndrome characterized by thrombocytopaenia, non-autoimmune haemolytic anaemia and renal impairment. Pathological alterations in kidney samples show thrombotic microangiopathy. The underlying pathogenesis is endothelial cell injury with thrombotic occlusion of the arterioles and capillaries. A variety of causes have been identified, associated with infection of Escherichia coli O157:H7, environmental factors as immunosuppressive drugs and genetic deficiencies in complement regulatory factors. The latter is called atypical haemolytic–uraemic syndrome (aHUS). Here, we present a patient with severe aHUS with complement factor H deficiency triggered by cocaine use and recurrence after kidney transplantation. The patient restarted haemodialysis for severe renal insufficiency and anti-C5 antibody eculizumab was used as salvage treatment with progressive recovery of graft function and suppression of dialysis.

Hepatitis C virus (HCV) infection is an important problem in the patient with end-stage renal disease. After transplantation, liver disease is more frequent in HCV-positive patients than in HCV-negative patients. In the long run, this leads to important liver complications. The patients have a higher risk for developing proteinuria and infections. Long-term patient and graft survival rates are lower in HCV-positive patients than in HCV-negative graft recipients. Mortality is higher, mainly as a result of liver disease and infections. Despite this, transplantation is the best option for the HCV-positive patient with end-stage renal disease. Transplantation of HCV-positive kidneys should be offered to HCV-positive recipients in whom HCV RNA is detected in the serum. Finally, several measures after transplantation minimize the consequences of HCV infection. Adjustment of immunosuppression and careful follow-up in the outpatient clinic for early detection of proteinuria, infection, or worsening of liver disease are mandatory.

Hepatitis C virus (HCV) infection is a common problem in renal transplant patients, associated with an increase in morbidity and mortality. HCV infection is associated with a lower graft and patient survival. The problem of HCV infection is the increase in viral load and liver transaminases after renal transplantation secondary to immunosuppressive therapy. After renal transplantation, interferon therapy is not recommended because of the risk for acute rejection and acute nephritis. In this context, it is absolutely necessary to consider the evaluation and treatment of HCV infection during the dialysis period. Several studies have defined the benefits of interferon therapy in dialysis patients, with rates of maintenance response significantly higher than in the general population. The difference in the pharmacokinetic profile of interferon in dialysis patients could justify its higher efficacy.

Patients with chronic renal failure (CRF) show limited exercise tolerance, classically attributed to anemia. However, persistence of abnormally low peak oxygen consumption, even after restoration of hemoglobin concentration with recombinant erythropoietin therapy and studies of muscle bioenergetics, suggests that the problem is located beyond hemoglobin oxygen transport. The present study is designed to assess mitochondrial respiratory chain (MRC) function from skeletal muscle of patients with CRF to determine whether there is impairment in mitochondrial oxidative capacity. We studied six young patients with CRF on regular hemodialysis and erythropoietin therapy and six healthy controls matched by age, sex, anthropometric characteristics, and physical activity. Muscle biopsy of the quadriceps was performed, and mitochondria were isolated. Mitochondrial content was estimated by means of mitochondrial yield and citrate synthase activity. Maximal capacity for oxygen consumption was measured polarographically using complex I, II, III, and IV substrates of the MRC. Individual enzyme activities of MRC complexes I to V were determined spectrophotometrically. Membrane lipid peroxidation was estimated by cis-parinaric fluorescence. Compared with controls, patients with CRF showed preserved mitochondrial content, conserved respiratory activity, intact enzyme activity of MRC complexes, and no increase in lipid peroxidation. We therefore conclude that mitochondrial function is preserved in young patients with CRF.

Summary Current genome-editing systems generally rely on inducing DNA double-strand breaks (DSBs). This may limit their utility in clinical therapies, as unwanted mutations caused by DSBs can have deleterious effects. CRISPR/Cas9 system has recently been repurposed to enable target gene activation, allowing regulation of endogenous gene expression without creating DSBs. However, in vivo implementation of this gain-of-function system has proven difficult. Here, we report a robust system for in vivo activation of endogenous target genes through trans -epigenetic remodeling. The system relies on recruitment of Cas9 and transcriptional activation complexes to target loci by modified single guide RNAs. As proof-of-concept, we used this technology to treat mouse models of diabetes, muscular dystrophy, and acute kidney disease. Results demonstrate that CRISPR/Cas9-mediated target gene activation can be achieved in vivo , leading to measurable phenotypes and amelioration of disease symptoms. This establishes new avenues for developing targeted epigenetic therapies against human diseases. Video Abstract

International audience; This protocol presents recently developed methodologies for the differentiation of human pluripotent stem cells (hPSCs) into ureteric bud (UB) progenitor-like cells. Differentiation of human PSCs to UB progenitor-like cells allows for the generation of chimeric kidney cultures in which the human cells can self-assemble into chimeric 3D structures in combination with embryonic mouse kidney cells over a period of 18 d. UB progenitor-like cells are generated by a two-step process that combines in vitro commitment of human PSCs, whether embryonic stem cells (ESCs) or induced PSCs (iPSCs), under chemically defined culture conditions, with ex vivo cultures for the induction of 3D organogenesis. The models described here provide new opportunities for investigating human kidney development, modeling disease, evaluating regenerative medicine strategies, as well as for toxicology studies.

Pregnancy-associated atypical hemolytic uremic syndrome is a systemic disease associated with high morbidity and mortality rates, caused by dysregulation of the alternative complement pathway, leading to uncontrolled complement activation resulting in thrombotic microangiopathy. This condition can be effectively treated by anti-C5 therapy, which controls complement activation. Treatment can be safely discontinued after complete remission and resolution of the precipitating cause, especially in patients with a low-risk genetic profile.

On-line haemodiafiltration (OL-HDF) is currently the most effective technique and several randomised studies and meta-analyses have seen a reduction in mortality and an association directly related with convective volume is observed. Blood flow (Qb) limits the infusion rate to 25-33 % and is the main limiting factor for reaching an optimum substitution volume. With the recent incorporation of monitors with auto-substitution systems, the aim of the study was to assess the effect of Qb variations on convective volume and purifying capacity.23 patients, 17 men and 6 women, were included, with an average age of 65.5plusmn;10 years, time on dialysis 292.2plusmn; 15 minutes, which were in the OL-HDF programme with the 5008 Cordiax monitor with auto-substitution. Each patient was analysed over 5 sessions in which only the Qb was changed (250, 300, 350, 400 and 450 ml/min). In each session the substitution volume, total convective volume and parameters of dialysis were measured. The concentration of urea (60 Da), creatinine (113 Da),beta;2-microglobulin (11,800 Da), myoglobin (17,200 Da), prolactin (23,000 Da),alpha;1-microglobulin (33,000 Da) andalpha;1-acid glycoprotein (40,000 Da) in plasma was measured at the start and end of each session in order to calculate the percentage of reduction of these solutes.The trans-membrane pressure was less, with Qb 250 ml/min. A significant increase in convective volume was observed with the increase in Qb, 23.7, 26.9, 30.2, 32.8 and 35.2 l/session to 250, 300, 350, 400 and 450 ml/min, respectively (Plt; 0.001), representing a percentage of total purified blood of 33.2, 31.2, 30.2, 28.7 and 27.3 % respectively. The percentages of reduction of urea and creatine progressively increased with Qb, slight differences were observed withbeta;2-microglobulin and myoglobin, and no changes were observed in the larger molecules.For each 50 ml/min increase in Qb, the convective volume increased by between 8 and 12 ml/min. The auto-substitution system strengthens the lowest Qbs in the percentage of convective volume with regards to total purified blood. Qb increases the purifying capacity of small molecules, favouring that ofbeta;2-microglobulin and myoglobin, and does not influence molecules of a greater molecular weight.nbsp

Mortality and morbidity are significantly higher among patients with dialysis catheters, which has been associated with chronic activation of the immune system. We hypothesized that bacteria colonizing the catheter lumen trigger an inflammatory response. We aimed to evaluate the inflammatory profile of hemodialysis patients before and after locking catheters with an antimicrobial lock solution. High-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), IL-10, and tumor necrosis factor alpha (TNF-α) were measured in serum, and levels of mRNA gene expression of IL-6, IL-10, and TNF-α were analyzed in peripheral blood mononuclear cells (PBMC). Samples were obtained at baseline and again after 3 months' use of taurolidine-citrate-heparin lock solution (TCHLS) in 31 hemodialysis patients. The rate of catheter-related bloodstream infections (CRBSI) was 1.08 per 1,000 catheter-days in the heparin period and 0.04 in the TCHLS period ( P = 0.023). Compared with the baseline data, serum levels of hs-CRP and IL-6 showed median percent reductions of 18.1% and 25.2%, respectively ( P < 0.01), without significant changes in TNF-α or IL-10 levels. Regarding cytokine gene expression in PBMC, the median mRNA expression levels of TNF-α and IL-6 decreased by 20% ( P < 0.05) and 19.7% ( P = 0.01), respectively, without changes in IL-10 expression levels. The use of TCHLS to maintain the catheter lumen sterility significantly reduces the incidence of CRBSI and improves the inflammatory profile in hemodialysis patients with tunneled catheters. Further studies are needed to evaluate the potential beneficial effects on clinical outcomes.

The hemolytic uremic syndrome (HUS) is a clinical entity characterized by thrombocytopenia, non-immune hemolytic anemia and renal impairment. Kidney pathology shows thrombotic microangiopathy (TMA) with endothelial cell injury leading to thrombotic occlusion of arterioles and capillaries. Traditionally, HUS was classified in 2 forms: Typical HUS, most frequently occurring in children and caused by Shiga-toxin-producing bacteria, and atypical HUS (aHUS). aHUS is associated with mutations in complement genes in 50-60% of patients and has worse prognosis, with the majority of patients developing end stage renal disease. After kidney transplantation HUS may develop as a recurrence of aHUS or as de novo disease. Over the last years, many studies have demonstrated that complement dysregulation underlies the endothelial damage that triggers the development of TMA in most of these patients. Advances in our understanding of the pathogenic mechanisms of aHUS, together with the availability of novel therapeutic options, will enable better strategies for the early diagnosis and etiological treatment, which are changing the natural history of aHUS. This review summarizes the aHUS clinical entity and describes the role of complement dysregulation in the pathogenesis of aHUS. Finally, we review the differential diagnosis and the therapeutic options available to patients with aHUS.

On-line haemodiafiltration (OL-HDF) is based on the controlled administration of large volumes of replacement ultrapure dialysate to the extracorporeal blood circuit of dialysis. It is currently the most effective technique for eliminating small and large uraemic toxins. Recent studies have observed a direct association between a decrease in mortality and the received convective volume. The latest Fresenius 5008 (5008 CorDiax) monitor software update enables the automation of the replacement volume without requiring total protein and haematocrit values, with the aim of maximising convection.The studyrsquo;s objective was to evaluate the recent version of the 5008 monitor software, compared to the previous version, on the impact on total convective volume.We included 63 patients (44 males and 19 females), with a mean age of 65.2nbsp;plusmn;nbsp;15 years, on OL-HDF. Each patient was analysed in 6 sessions; 3 with the 5008 monitor and 3 with the 5008 CorDiax monitor. The replacement volume, total convective volume and dialysis parameters were determined in each session.No significant differences were observed in blood, venous or transmembrane pressure, nor was there an increase in the number of alarms or coagulation of lines or dialysers. A significant increase of replacement fluid volume, from 27.2 to 31.2nbsp;L/session, was observed using the CorDiax software. Total convective volume increased from 29.5 to 33.3 L/session, representing an effective convective volume increase from 26nbsp;% to 29.6nbsp;% of total filtered blood.The 5008 dialysis monitor software update has meant a 13nbsp;% increase of total convective volume and a 3.5nbsp;% increase of total filtered blood.

Methods We analyzed all PRA-negative patients who received a first kidney transplant from an HLA-identical living donor. The patients received no antibody induction. An intraoperative bolus of 500 mg of methylprednisolone was administered. Then, steroid therapy was withdrawn within one week. Tacrolimus and mycophenolate treatment were started 3 days before transplantation with tacrolimus target levels of 4 to 8 ng/mL. In the absence of rejection, tacrolimus was withdrawn between 3 and 12 months post-transplant to reach mycophenolate mofetil monotherapy of 2 g/day or equivalent. Results Six patients were treated with the above protocol. At last follow-up, graft and patient survival were 100%. MDRD glomerular filtration rates were 54, 60, and 62 mL/min at 3 months, 12 months and last follow-up, respectively. None of the patients developed PRA post-transplant. One episode of acute rejection Banff IA occurred 9 years after transplantation due to non-adherence with good outcome after treatment. The mean number of concomitant drugs given with mycophenolate was 2.6. Four patients needed antihypertensive drugs. Conclusion Steroid-free de novo treatment and calcineurin-inhibitor weaning with mycophenolate monotherapy is feasible in first HLA-identical kidney transplantation from a living sibling. Although recipients of a first HLA-identical living-donor kidney transplant seem to need less immunosuppression, there are no guideline recommendations for these patients, and few prospective trials are available.

International audience; Heart failure is a leading cause of mortality and morbidity in the developed world, partly because mammals lack the ability to regenerate heart tissue. Whether this is due to evolutionary loss of regenerative mechanisms present in other organisms or to an inability to activate such mechanisms is currently unclear. Here we decipher mechanisms underlying heart regeneration in adult zebrafish and show that the molecular regulators of this response are conserved in mammals. We identified miR-99/100 and Let-7a/c and their protein targets smarca5 and fntb as critical regulators of cardiomyocyte dedifferentiation and heart regeneration in zebrafish. Although human and murine adult cardiomyocytes fail to elicit an endogenous regenerative response after myocardial infarction, we show that in vivo manipulation of this molecular machinery in mice results in cardiomyocyte dedifferentiation and improved heart functionality after injury. These data provide a proof of concept for identifying and activating conserved molecular programs to regenerate the damaged heart.

Background. The aim of the present study was to determine the effect of losartan on transforming growth factor-β1 (TGF-β1) plasma levels and urinary albumin excretion (UAE) in patients with type 2 diabetes mellitus, mild hypertension and microalbuminuria. Methods. Fourteen patients (eight males, aged 55 ± 6 years) with type 2 diabetes mellitus, mild arterial hypertension and microalbuminuria, participating in an open, uncontrolled, pilot study were included. Patients were treated for 8 weeks with losartan. TGF-β1 plasma levels, UAE and 24-h blood pressure monitoring were determined at baseline and at 4 and 8 weeks. Results. At 4 and 8 weeks of treatment, a reduction was observed in TGF-β1 plasma levels (5.5 ± 4.5 vs 2.0 ± 0.6 and 2.6 ± 1.0 ng/ml, P

Summary Hepatitis C virus (HCV) infection is the most frequent cause of liver disease after renal transplantation. Its clinical course is irrelevant in the short term, except for rare cases of fibrosing cholestatic hepatitis. However, in the long run, HCV infection can lead to major liver complications. Because interferon (IFN) is generally contraindicated in renal transplant patients, the best approach is to treat patients on dialysis. Until more information with pegylated-IFN is available, the use of alpha-IFN monotherapy is recommended. Most of the patients with sustained virological response remain HCV RNA negative after transplantation. HCV-positive renal transplant patients have a higher risk for proteinuria, chronic rejection, infections and post-transplant diabetes (PTDM). Long-term patient- and graft-survival rates are lower in HCV-positive patients. Mortality is higher, mainly as a result of liver disease and infections. HCV can contribute to the development of certain neoplasias such as post-transplant lymphoproliferative disease (PTLD). HCV infection is also an independent risk factor for graft loss. PTDM, transplant glomerulopathy and HCV-related glomerulonephritis can contribute to graft failure. Despite this, transplantation is the best option for end-stage renal disease in HCV-positive patients. Several measures to minimize the consequences of HCV infection have been recommended. Adjustment of immunosuppression and careful follow up in the outpatient clinic for early detection of HCV-related complications are mandatory.

Renal transplantation procedures in patients older than 60 years of age have clearly improved in recent years. In the cyclosporin era, graft and patient survival are good. However, older patients exhibit a higher mortality, especially from infectious and cardiovascular causes, than young patients. In this article we review the immunosuppressive treatment in older patients, analyse what drugs can be used and finally propose several immunosuppressive combinations to treat this group of patients. Currently, new immunosuppressive drugs enable more flexible immunosuppressive protocols. Nevertheless, to avoid overimmunosuppression, elderly patients should be treated with lower doses and fewer immunosuppressive drugs.

Introduction. A previous trial in renal transplantation comparing sirolimus (rapamycin) to cyclosporine (CsA) ina triple-drug therapy regimen with azathioprine and corticosteroids found that the incidence of acute rejection was similar (approximately 40%) with a trend for better renal function with sirolimus. Methods. In 14 European centers, first cadaveric renal allograft recipients were randomized to receive sirolimus (n=40) or CsA (n=38) in an open-label design. All patients received corticosteroids and mycophenolate mofetil 2 g/day. Sirolimus and CsA were concentration controlled; trough levels of mycophenolic acid and prednisolone were also measured. Results. At 12 months, graft survival(92.5% sirolimus vs. 89.5% CsA), patient survival (97.5% sirolimus vs. 94.7% CsA), and the incidence of biopsy-proven acute rejection (27.5% sirolimus vs. 18.4% CsA) were not statistically different. The use of antibodies to treat suspected rejection episodes was also similar (7.5% sirolimus vs. 5.3% CsA). More sirolimus patients received bolus steroid therapy (20 vs. 11, P=0.068). From month 2 onward, the calculated glomerular filtration rate was consistently higher in sirolimus-treated patients. The adverse events reported more frequently with sirolimus were thrombocytopenia (45% vs. 8%) and diarrhea (38% vs. 11%). In the CsA group, increased creatinine (18% vs. 39%), hyperuricemia (3% vs. 18%), cytomegalovirus infection (5% vs. 21%), and tremor (5% vs. 21%) were observed significantly more often. Discussion. Patient and graft survival and the incidence of biopsy-proven acute rejection at 12 months were comparable between sirolimus and CsA, whereas safety profiles were different. These data suggest that sirolimus may be used as primary therapy for the prevention of acute rejection.

Background. Hepatitis C virus (HCV) infection represents an important problem for the dialysis population due to its high prevalence and the long-term development of chronic liver disease, particularly following renal transplantation. Methods. In order to assess the efficacy and tolerance of interferon (IFN) in the treatment of chronic hepatitis C in haemodialysis (HD) patients and their clinical course following renal transplantation, a multicentre, randomized, open-label study was conducted to compare IFN therapy vs a control group. Results. Nineteen HCV RNA-positive patients received 3×10 6 U of IFN s.c., three times a week (post-HD), and 17 HCV RNA-positive patients were assigned to the control group. Tolerance to IFN therapy was good in nine patients, while treatment was discontinued in the other 10 due to the occurrence of side effects. HCV RNA was negative at the end of treatment in 14 out of 19 patients (74%) receiving IFN and in one patient (5%) in the control group. Six out of the 14 patients who initially responded to IFN therapy had a virological relapse (43%). Eight patients (42%) remained HCV RNA-negative, three of them until the day that renal transplantation (RT) was performed (7, 12 and 27 months, respectively), as did five patients on HD during the follow-up (27±5 months). Eight out of the nine patients (89%) who completed therapy were HCV RNA-negative at the end of treatment, and seven of them (78%) remained HCV RNA-negative during the follow-up on dialysis (21±8 months). Mean transaminase (ALT) values were significantly decreased following IFN therapy, while no changes were observed during the follow-up period in the control group. Fifteen patients (10 in the treatment group and five in the control group) underwent RT. Three patients in the treatment group were HCV RNA-negative at RT, and one of them had a virological relapse 20 months after RT, while the other two remained HCV RNA-negative at 3 months and 24 months after RT, respectively. In contrast to the control group, transaminase (ALT) remained within normal limits in all patients in the treatment group. Finally, during the post-RT follow-up, the transaminase mean values were significantly lower in treated patients vs patients in the control group (P

Background. Sirolimus (rapamycin) is a potent immunosuppressant with a mechanism of action different from cyclosporine (CsA) or tacrolimus. Methods. In 11 European centers, first cadaveric renal allograft recipients were randomized to CsA (n=42) or sirolimus (n=41). Dosing of these agents was concentration-controlled and open-labeled. All patients received corticosteroids and azathioprine. Results. At 12 months, graft survival (98% sirolimus vs. 90% CsA), patient survival (100% vs. 98%), and incidence of biopsy-confirmed acute rejection (41% vs. 38%) were similar. Serum creatinine was lower with sirolimus, significantly (P

Transplant recipients receiving immunosuppressive therapy are at increased risk of active cytomegalovirus (CMV) infection and disease. Without appropriate prophylaxis, as many as 80% of solid organ transplant recipients may experience CMV infection. In addition to the direct effects of CMV, infection may be associated with a range of indirect effects, including an increase in risk of other infections, as well as a higher incidence of rejection, graft loss and death. The indirect effects of CMV infection can vary depending on the transplanted organ. For example, CMV-infected kidney transplant recipients may be at increased risk of cardiovascular disease and diabetes, while CMV infection in liver transplant recipients may potentiate hepatitis C infection and increase the risk of post-transplant lymphoproliferative disease. Indirect effects result from a number of pathological processes, including immune modulation and immunosuppression, generation of cytotoxic, pro-inflammatory responses, and smooth muscle proliferation. Prophylactic treatment with antiviral medication can reduce the risk of CMV disease, thereby improving graft survival and overall outcomes, particularly in kidney and heart transplant recipients. Antiviral prophylaxis should be considered for all patients at risk of CMV infection after solid organ transplantation. In this paper we review the main indirect effects of CMV infection in solid organ transplant recipients, and the impact of CMV prophylaxis on these effects.

Background/Aims: Online dialysance (Kt) and thermodilution (BTM-Qa) methods could be important components in vascular access monitoring programs. This study evaluated the efficiency of these two methods in reducing the thrombosis rate and access-related costs compared with a historic control group. Methods: We studied 148 hemodialysis patients with arteriovenous fistulas (control group, n = 74) for 2 years. During the study period, the indications for vascular treatments were the Kt reduction ≥20% with respect to baseline values or Qa 20%). Results: During the study period, we detected 16 cases of vascular dysfunction. The Kt value after vascular treatment was 71.1 liters (59 liters; p = 0.001) and BTM-Qa was 1,218.6 ml/min (519.7 ml/min; p = 0.001). Compared with the control group, the thrombosis rate was 0.027 versus 0.148 episodes/patient-year (p = 0.009) and the total access-related cost was EUR 22,293 versus 47,467 (p = 0.033). Conclusions: This study suggests that a combined monitoring program based on Kt and BTM-Qa represents an effective screening method that significantly reduces the thrombosis rate and economic costs of vascular treatments.

BACKGROUND Immunosuppression after kidney transplantation has been associated with weight gain. The aim was to evaluate if sirolimus (SRL) had a different effect on weight gain than calcineurin inhibitor (CNI). METHODS Data on body weight in different patient populations were analyzed at several time points: (a) SRL (CNI-free) versus cyclosporine A (CsA) treatment de novo, (b) CsA+SRL versus CsA (SRL-free) treatment de novo, (c) SRL+tacrolimus elimination at 3 months versus SRL+mycophenolate mofetil versus tacrolimus+mycophenolate mofetil de novo, and (d) conversion from CNI to SRL versus CNI in maintenance patients. RESULTS Patients were analyzed from de novo transplantation trials (n=1863) and from the conversion study (n=742). At baseline, weight in the SRL-containing and SRL-free treatment arms was not different, but weight gain was significantly less pronounced in SRL in de novo treatment (group 1: 2.8±4.6 vs. 6.2±6.6 kg every 2 years, P=0.020; group 2: 6.1±9.5 vs. 9.6±9.1 kg every 2 years, P

BACKGROUND: The association of anemia with outcomes after renal transplantation (RT) is unclear. METHODS: We performed a retrospective study that included patients who received a RT in Spain in 2007. We collected data on anemia (hemoglobin [Hb]

International audience; Diseases affecting the kidney constitute a major health issue worldwide. Their incidence and poor prognosis affirm the urgent need for the development of new therapeutic strategies. Recently, differentiation of pluripotent cells to somatic lineages has emerged as a promising approach for disease modelling and cell transplantation. Unfortunately, differentiation of pluripotent cells into renal lineages has demonstrated limited success. Here we report on the differentiation of human pluripotent cells into ureteric-bud-committed renal progenitor-like cells. The generated cells demonstrated rapid and specific expression of renal progenitor markers on 4-day exposure to defined media conditions. Further maturation into ureteric bud structures was accomplished on establishment of a three-dimensional culture system in which differentiated human cells assembled and integrated alongside murine cells for the formation of chimeric ureteric buds. Altogether, our results provide a new platform for the study of kidney diseases and lineage commitment, and open new avenues for the future application of regenerative strategies in the clinic.

Primary central nervous system post-transplant lymphoproliferative disease (CNS PTLD) is a serious complication after solid organ transplantation that has not received much attention so far. However, it could become a more frequent problem with the introduction of new biological agents. We identified five cases with CNS PTLD in our center who were transplanted between 1986 and 2007, three men and two women, with a mean age of 55.9 years (range 42–74). Three patients had received only kidney transplant and two patients had received a kidney–pancreas transplant. The mean time from first symptoms until diagnosis was 3.5 months (2–6). One patient was diagnosed post-mortem in autopsy. The mean time from transplantation to onset of neurological symptoms was 73.8 months (31–144). The initial clinical manifestation was heterogeneous: all five cases showed headache, four cases presented with gait disturbance, one with dysarthria and two with a confusional state. Epstein–Barr virus (EBV) immunoglobulin (Ig)G serology was positive in four out of five cases; in situ hybridization for EBV in brain biopsy samples was positive in three cases, negative in one and not available in one. In four patients, EBV polymerase chain reaction (PCR) was positive in cerebrospinal fluid (CSF). After diagnosis, overall immunosuppressive load was lowered in all patients (n = 4). Three patients died at 8–104 weeks (mean 40 weeks) after diagnosis and one patient is still alive 20 months after diagnosis. CNS PTLD is a complication difficult to diagnose, frequently diagnosed too late and often refractory to treatment. A more aggressive screening might be necessary in patients even with mild CNS symptoms.

The current clinical guidelines recommend indirect access blood flow (Qa) measurement as one of the most important components in vascular access maintenance programs. The best-know methods are doppler ultrasound (DU) and saline dilution method.This study evaluates the efficiency of Qa measurement with thermodilution method (TD) in comparison with the DU.Transversal study in 64 patients in hemodialysis (41 men); mean age 59.9 years with 54 AVFs and 10 PTFE. Qa reference value was obtained with DU in brachial artery (AVFs) or at the zone of arterial puncture (AVGs). Bland-Altman and interclass correlation coefficient (ICC) were used to study accuracy.Mean values obtained with DU-Qa were 1426 ± 753 mL/min AVFs and 1186 ± 789 mL/min AVGs. The mean Qa with TD was 1372 ± 770 AVFs (bias 54.6; ICC 0.923) and 1176 ± 758 AVGs (bias 10.2; ICC 0.992). In the subgroup of 28 patients with radiocephalic latero-terminal AVFs the DU-Qa was 1232 ± 767 mL/min. The Qa was in radial artery 942 (ICC 0.805); radial-ulnar artery 1103 (ICC 0.973); cephalic vein 788 (ICC 0.772) and TD 1026 (ICC 0.971). We detected 5 cases of significant stenosis. After endovascular treatment the Kt was 79 liters (61; p=0.043) and TD-Qa 895 mL/min (663; p=0.043).TD represents a good indirect method of Qa measurement. In the subgroup of patients with radiocephalic AVFs, Qa measurements in the radial and ulnar artery are more accurate. Therefore, in this situation the TD method obtained an excellent correlation in comparison to brachial artery.

The increased incidence of Kaposi's sarcoma (KS) in organ transplantation has been related to the KS herpesvirus and the permissive effect of immunosuppressive therapy. Calcineurin inhibitors are the cornerstone of immunosuppression in organ transplantation, although they could promote tumor progression. In contrast, sirolimus, a new immunosuppressive agent, exhibits potent antitumor activity. We postulated that conversion from cyclosporine to sirolimus in patients with KS could favor regression of KS lesions without increasing the risk of graft rejection. Two renal transplant recipients with KS underwent conversion from cyclosporine to sirolimus. Both patients showed complete regression of KS lesions and excellent clinical and functional results. Sirolimus offers a new and promising approach to the management of posttransplantation KS and probably to other types of malignancies in organ transplant recipients.