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IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide, but its etiologic mechanisms are still poorly understood. Different prevalences among ethnic groups and familial aggregation, together with an increased familial risk, suggest important genetic influences on its pathogenesis. A locus for familial IgAN, called "IGAN1," on chromosome 6q22-23 has been described, without the identification of any responsible gene. The partners of the European IgAN Consortium organized a second genomewide scan in 22 new informative Italian multiplex families. A total of 186 subjects (59 affected and 127 unaffected) were genotyped and were included in a two-stage genomewide linkage analysis. The regions 4q26-31 and 17q12-22 exhibited the strongest evidence of linkage by nonparametric analysis (best P=.0025 and .0045, respectively). These localizations were also supported by multipoint parametric analysis, in which peak LOD scores of 1.83 ( alpha =0.50) and 2.56 ( alpha =0.65) were obtained using the affected-only dominant model, and by allowance for the presence of genetic heterogeneity. Our results provide further evidence for genetic heterogeneity among families with IgAN. Evidence of linkage to multiple chromosomal regions is consistent with both an oligo/polygenic and a multiple-susceptibility-gene model for familial IgAN, with small or moderate effects in determining the pathological phenotype. Although we identified new candidate regions, replication studies are required to confirm the genetic contribution to familial IgAN.

BACKGROUND: Chronic kidney disease (CKD) patients affected by mineral bone disorders (MBD) have higher rates of all-cause and cardiovascular-related mortality. Approximately, one-third of dialysis patients have low serum parathyroid hormone (PTH) levels (≤ 150 pg/mL). However, the reason why these patients have higher mortality compared to patients with normal PTH levels has not yet been fully elucidated. METHODS: The FARO study was performed on 2453 Italian patients followed prospectively from 28 dialysis centres over a 2-year period. Data were collected every 6 months and end points included time-to-death cumulative probability in patients with serum intact PTH (iPTH) ≤ 150 pg/mL and the effect of vitamin D receptor activation (VDRA) therapy. Kaplan-Meier curves and proportional hazards regression models stratified by PTH levels (i.e. ≤ 150 and >150 pg/mL) were used to determine cumulative probability of time-to-death and adjusted hazard ratios (HRs) for demographic, clinical and CKD-MBD treatment characteristics. RESULTS: The cumulative probability of death was higher (P < 0.01) for patients with serum iPTH levels ≤ 150 pg/mL [25.1%, 95% confidence interval (CI): 22.1-28.5 at 18 months] versus those with serum iPTH levels within the normal range (18.0%, 95% CI: 16.1-20.1). In a model with time-dependent covariates restricted to time periods when patients had iPTH levels ≤ 150 pg/mL, lower mortality was observed in patients treated with VDRA [i.e. HR = 0.62, 95% CI: 0.42-0.92 for oral or intravenous (IV) calcitriol; HR = 0.18, 95% CI: 0.04-0.8 for IV paricalcitol] versus those not receiving any VDRA (P < 0.01) independently of other variables. Patients who received IV paricalcitol, compared with either oral or IV calcitriol, showed reduced mortality, but this was not statistically significant (HR = 0.3, 95% CI: 0.07-1.31, P = 0.11). CONCLUSION: Results from this observational study suggest that VDRA therapy was associated with improved survival in dialysis patients, even with low serum iPTH levels.

AIMS: In recent years, treatment options for secondary hyperparathyroidism (SHPT) have increased (e.g., paricalcitol, calcimimetics). To determine the impact these new treatments have on achieving K/DOQI targets, an observational, prospective survey was undertaken. METHODS: Four 6-month time-spaced surveys of 2,637 patients in 28 Italian dialysis units were performed. Patient demographic information; use of vitamin D or calcimimetics; and changes in parathyroid hormone (PTH), calcium (Ca) and phosphate (P) levels were evaluated. RESULTS: Over the course of the survey, use of calcitriol decreased (from 62.1% at baseline to 44.5% at month 18; p

Adducins are cytoskeletal actin-binding proteins (α, β, γ) that function as heterodimers and heterotetramers and are encoded by distinct genes. Experimental and clinical evidence implicates α- and β-adducin variants in hypertension and renal dysfunction. Here, we have addressed the role of α- and β-adducin on glomerular function and disease using β-adducin null mice, congenic substrains for α- and β-adducin from the Milan hyperten- sive (MHS) and Milan normotensive (MNS) rats and patients with IgA nephropathy. Targeted deletion of β- adducin in mice reduced urinary protein excretion, preceded by an increase of podocyte protein expression (phosphonephrin, synaptopodin, α-actinin, ZO-1, Fyn). The introgression of polymorphic MHS β-adducin locus into MNS (Add2, 529R) rats was associated with an early reduction of podocyte protein expression (nephrin, synaptopodin, α- actinin, ZO-1, podocin, Fyn), followed by severe glomerular and interstitial lesions and increased urinary protein excretion. These alterations were markedly attenuated when the polymorphic MHS α-adducin locus was also present (Add1, 316Y). In patients with IgA nephropathy, the rate of decline of renal function over time was associated to polymorphic β-adducin (ADD2, 1797T, rs4984) with a significant interaction with α-adducin (ADD1, 460W, rs4961). These findings suggest that adducin genetic variants participate in the development of glomerular lesions by modulating the expression of specific podocyte proteins.

BACKGROUND: Relative survival, a methodology previously used in epidemiologic studies of cancer, compares the observed survival of a patient cohort with expected survival derived from general population life tables. We examined relative survival in patients treated by long-term dialysis in the Italian Dialysis and Transplantation Registry in order to determine the prognosis of dialysis patients. STUDY DESIGN: Cohort study drawn from a registry. SETTING & PARTICIPANTS: Patients enrolled in the Italian Dialysis and Transplantation Registry. FACTORS: Sex, age, primary kidney disease, renal replacement therapy modality, and main comorbid conditions. OUTCOMES: Death from any cause. MEASUREMENTS: Relative survival ratio (the ratio of observed survival in the population of interest to the survival expected given the age- and period-specific mortality of the general population) and excess mortality rate (difference between observed and expected mortality rates). RESULTS: In January 2000 to December 2008, a total of 27,642 patients were included. The 5-year relative survival estimate was 55.6% (95% CI, 54.7%-56.5%). The excess mortality rate showed a peak at 3 months (21 deaths/100 patient-years), then decreased, becoming constant from the end of year 1 to year 8, with leveling off at about 10 deaths/100 patient-years. Older age, systemic diseases, and diabetes showed the strongest association with excess mortality. Peritoneal dialysis was associated with a lower relative excess risk in only the first year of treatment. LIMITATIONS: The patient cohort comprises about half the Italian patients beginning dialysis therapy in the period. CONCLUSIONS: This study highlights the applicability of relative survival methods in dialysis patients. This measure allows estimation of disease prognosis and severity comparisons among chronic diseases. The excess mortality rate appears to be a more sensitive and informative measure than the simple proportion of survivors.

Bertinetto, Francesca Eleonora et al.-- European IgA Nephropathy Consortium, [Background] IgA nephropathy (IgAN) is not generally considered a hereditary disease, even though extensive evidence suggests an undefined genetic influence. Linkage analysis identified a number of genome regions that could contain variations linked to IgAN., [Methods] In this case-control association study, genes possibly involved in the development of IgAN were investigated. DNA samples from 460 North Italian patients with IgAN and 444 controls were collected. Candidate genes were selected based on their possible functional involvement (6 genes) or because of their location within linkage-identified genomic regions IGAN2 and IGAN3 (5 and 13 genes within chromosome 4q26-31 and 17q12-22, respectively). One hundred and ninety-two tag and functional single-nucleotide polymorphisms (SNPs) were typed with Veracode GoldenGate technology (Illumina)., [Results] C1GALT1 showed an association with IgAN (rs1008898: P = 0.0019 and rs7790522: P = 0.0049). Associations were found when the population was stratified by gender (C1GALT1, CD300LG, GRN, ITGA2B, ITGB3 in males and C1GALT1, TRPC3, B4GALNT2 in females) and by age (TLR4, ITGB3 in patients aged, [Conclusions] Age and gender are likely to evidence distinct immunological and inflammatory reactions leading to individual susceptibility to IgAN. Overall, a genetic predisposition to sporadic IgAN was found. We might hypothesize that C1GALT1 and TLR4 polymorphisms influence the risk to develop IgAN and proteinuria, respectively. © 2012 The Author., This study was supported by a Ph.D. research fellowship from the University of Turin and a health research project funding by Regione Piemonte.

BACKGROUND: Chronic kidney disease (CKD) patients affected by mineral bone disorders (MBD) have higher rates of all-cause and cardiovascular-related mortality. Approximately, one-third of dialysis patients have low serum parathyroid hormone (PTH) levels (≤ 150 pg/mL). However, the reason why these patients have higher mortality compared to patients with normal PTH levels has not yet been fully elucidated. METHODS: The FARO study was performed on 2453 Italian patients followed prospectively from 28 dialysis centres over a 2-year period. Data were collected every 6 months and end points included time-to-death cumulative probability in patients with serum intact PTH (iPTH) ≤ 150 pg/mL and the effect of vitamin D receptor activation (VDRA) therapy. Kaplan-Meier curves and proportional hazards regression models stratified by PTH levels (i.e. ≤ 150 and >150 pg/mL) were used to determine cumulative probability of time-to-death and adjusted hazard ratios (HRs) for demographic, clinical and CKD-MBD treatment characteristics. RESULTS: The cumulative probability of death was higher (P < 0.01) for patients with serum iPTH levels ≤ 150 pg/mL [25.1%, 95% confidence interval (CI): 22.1-28.5 at 18 months] versus those with serum iPTH levels within the normal range (18.0%, 95% CI: 16.1-20.1). In a model with time-dependent covariates restricted to time periods when patients had iPTH levels ≤ 150 pg/mL, lower mortality was observed in patients treated with VDRA [i.e. HR = 0.62, 95% CI: 0.42-0.92 for oral or intravenous (IV) calcitriol; HR = 0.18, 95% CI: 0.04-0.8 for IV paricalcitol] versus those not receiving any VDRA (P < 0.01) independently of other variables. Patients who received IV paricalcitol, compared with either oral or IV calcitriol, showed reduced mortality, but this was not statistically significant (HR = 0.3, 95% CI: 0.07-1.31, P = 0.11). CONCLUSION: Results from this observational study suggest that VDRA therapy was associated with improved survival in dialysis patients, even with low serum iPTH levels.

Phosphate may promote the onset and progression of chronic nephropathies. Here we evaluated the relationships between baseline serum phosphate levels, disease progression, and response to ACE inhibition in 331 patients with proteinuric nephropathies in the prospective Ramipril Efficacy In Nephropathy (REIN) trial. Independent of treatment, patients with phosphate levels in the highest two quartiles progressed significantly faster either to ESRD or to a composite endpoint of doubling of serum creatinine or ESRD compared with patients with phosphate levels below the median (P < 0.001). Results were similar when we analyzed phosphate as a continuous variable (P ≤ 0.004). The renoprotective effect of ramipril decreased as serum phosphate increased (P ≤ 0.008 for interaction); this modification of the treatment effect by phosphate persisted despite adjusting for potential confounders such as GFR and urinary protein. In summary, these data suggest that phosphate is an independent risk factor for progression of renal disease among patients with proteinuric CKD, and high levels of phosphate may even attenuate the renoprotective effect of ACE inhibitors. Future trials should test whether reducing serum phosphate improves renal outcomes and optimizes the renoprotective effect of ACE inhibition.

Idiopathic IgA Nephropathy (IgAN) is the most common biopsy-proven glomerulonephritis worldwide. All races with the exception of Blacks and Indians are involved. Families with two or more relatives affected by IgAN may be observed in 15-20% of pedigrees of IgAN patients. Genome wide linkage study has been considered the most promising approach to identify IgAN susceptibility genes. Therefore, some European investigators constituted the European IgAN Consortium which was initially funded by the European Union. Data from linkage analysis studies, family association studies and case-control association studies are reported. To date, the Consortium has identified two loci (located on chromosomes 4q26-31 and 17q12-22), in addition to the previous study which described the first IgAN locus on chromosome 6q22-23. The functional mapping of genes involved in the disease proceeds from the identification of susceptibility loci identified by linkage analysis (step 1) to the isolation of candidate genes within gene disease-susceptibility loci, after obtaining information by microarray analysis carried out on peripheral leukocytes and renal tissue samples (step 2). Then, the process will proceed from the design of RNA interferenceagents against selected genes (step 3) to the application of systematically tested effect of RNA agents on functional cellular assay (step 4). The above combined high-throughput technologies will give information on the pathogenic mechanisms of IgAN. In addition, these data may indicate potential targets for screening, prevention and early diagnosis of the disease and more appropriate and effective treatment.

The number of patients on the waiting list for renal transplantation has progressively increased in the last decade, while the number of potential donors have remained the same. The expansion of the donor pool using marginal donors may represent a possible, although partial solution to this problem. Thus, the aim of the present analysis was to evaluate the graft survival of double renal transplant from marginal donors performed within the Associazione InterRegionale Trapianti (AIRT) and to assess whether this procedure is characterized by an increase in surgical complications.79 double renal transplants were performed from January 1st 1999 to December 31st 2002 in three AIRT transplant centers (Bari, Bologna, Torino). Immunosuppressive therapy for all patients included anti-IL-2 receptor antibodies, corticosteroids, tacrolimus and mofetil micophenolate.Graft survival was 90% at 36 months. Acute rejection incidence was 6.4%, while the incidence of surgical complications was 16.6%.The present study opens new perspectives to overcome the actual shortage of donor kidneys. Indeed, the use of marginal organs for double renal transplantation not suitable for single transplantation may create an additional pool of potential donors and significantly increase the number of kidney transplants.

Effects of different membranes and dialysis technologies on patient treatment tolerance and nutritional parameters. There is increasing evidence that the biochemical and cellular phenomena induced by blood/membrane/dialysate interactions contribute to dialysis-related intradialytic and long-term complications. However, there is a lack of large, prospective, randomized trials comparing biocompatible and bioincompatible membranes, and convective and diffusive treatment modalities. The primary aim of this prospective, randomized trial was to evaluate whether the use of polysulfone membrane with bicarbonate dialysate offers any advantages (in terms of treatment tolerance, nutritional parameters and pre-treatment β 2 -microglobulin levels) over a traditional membrane (Cuprophan®). A secondary aim was to assess whether the use of more sophisticated methods consisting of a biocompatible synthetic membrane with different hydraulic permeability at different ultrafiltration rate (highflux hemodialysis and hemodiafiltration) offers any further advantages. Seventy-one Centers were involved and stratified according to the availability of only the first two or all four of the following techniques: Cuprophan® hemodialysis (Cu-HD), low-flux polysulfone hemodialysis (LfPS-HD), high-flux polysulfone high-flux hemodialysis (HfPS-HD), and high-flux polysulfone hemodiafiltration (HfPS-HDF). The 380 eligible patients were randomized to one of the two or four treatments (132 to Cu-HD, 147 to LfPS-HD, 51 to HfPS-HD and 50 to HfPS-HDF). The follow-up was 24 months. No statistical difference was observed in the algebraic sum of the end points between bicarbonate dialysis with Cuprophan® or with low-flux polysulfone, or among the four dialysis methods under evaluation. There was a significant decrease in pre-dialysis plasma β 2 -microglobulin levels in high-flux dialysis of 9.04 ± 10.46 mg/liter (23%) and in hemodiafiltration of 6.35 ± 12.28 mg/liter (16%), both using high-flux polysulfone membrane in comparison with Cuprophan® and low-flux polysulfone membranes (P = 0.032). The significant decrease in pre-dialysis plasma β 2 -microglobulin levels could have a clinical impact when one considers that β 2 -microglobulin accumulation and amyloidosis are important long-term dialysis-related complications.

Since the occurrence of West Nile virus (WNV) infection in humans in 2008 in Italy, concerns have been raised about the potential risks associated with solid organ transplantation (SOT). A nationwide retrospective survey showed that 1.2% of SOT donors in 2009 were WNV-seropositive and demonstrated that human WNV infection is distributed throughout several Italian regions. Transmission of WNV or other arboviruses through SOT is a possibility and risk assessment should be carried out before SOT to avoid infection through transplantation.