52 research outputs found
Multicenter Experience with the Surfacer Inside-Out Access Catheter System in Patients with Thoracic Venous Obstruction: Results from the SAVE Registry.
ABSTRACT Purpose To report device performance and safety for the SurfacerŸ Inside-OutŸ access catheter system in patients with thoracic central venous obstruction (TCVO) requiring central venous access (CVA). Materials and Methods Five sites prospectively enrolled 30 patients requiring a tunneled dialysis catheter between February 2017 and September 2018 in the Surfacer System to Facilitate Access in Venous Obstructions (SAVE) Registry (NCT02875899). Patient demographics, medical history and type of TCVO were documented at enrollment. Device performance and adverse events were collected during the procedure and upon hospital discharge. Twenty-nine of the 30 patients enrolled required CVA for hemodialysis. Retrospective classification of TCVOs according to SIR Reporting Standards showed 9 patients (30%) had Type 4 obstructions, 8 (26.7%) had Type 3, 5 (16.7%) had Type 2 and 8 (26.7%) had Type 1 obstructions. Results Central venous cathters (CVCs) were successfully placed in 29 of 30 patients (96.7%). The procedure was discontinued in one patient due to vascular anatomical tortuosity. All 29 patients with successful CVC placement achieved adequate catheter patency and tip positioning. There were no device-related adverse events, catheter malposition, intra- or postprocedural complications. Mean time from device insertion to removal for the 29 patients who successfully completed the procedure was 24±14.9 (range 6 to 70) minutes. Mean fluoroscopy time was 6.8±4.5 (range 2.2 to 25.5) minutes. Conclusion The Surfacer Inside-Out procedure provides an alternative option to restore right-sided central venous access in patients with TCVO
Validation of plasma biomarker candidates for the prediction of eGFR decline in patients with type 2 diabetes
Objective:
The decline of estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes is variable and early interventions would likely be cost effective. We elucidated the contribution of 17 plasma biomarkers to the prediction of eGFR loss on top of clinical risk factors.
Research Design and Methods:
We studied participants in PROVALID, a prospective multinational cohort study of patients with type 2 diabetes and a follow up of more than 24 months (n = 2560; baseline median eGFR 84 mL/min/1.73m2, UACR 8.1 mg/g). The 17 biomarkers were measured at baseline in 481 samples using Luminex technology and ELISA. The prediction of eGFR decline was evaluated by linear mixed modeling.
Results:
In univariable analyses nine of the 17 markers showed significant differences in median concentration between the two groups. A linear mixed model for eGFR obtained by variable selection exhibited an adjusted R2 of 62%. A panel of twelve biomarkers was selected by the procedure and accounted for 34% of the total explained variability, of which 32% were due to five markers. Each biomarkerâs individual contribution to the prediction of eGFR decline on top of clinical predictors was generally low. When included into the model, baseline eGFR exhibited the largest explained variability of eGFR decline (R2 of 79%) and the contribution of each biomarker dropped below 1%.
Conclusions:
In this longitudinal study of patients with type 2 diabetes and maintained eGFR at baseline, 12 of the 17 candidate biomarkers were associated with eGFR decline, but their predictive power was low
Integrative analysis of prognostic biomarkers derived from multiomics panels for the discrimination of chronic kidney disease trajectories in people with type 2 diabetes
Clinical risk factors explain only a fraction of the variability of estimated glomerular filtration rate (eGFR) decline in people with type 2 diabetes. Cross-omics technologies by virtue of; a wide spectrum screening of plasma samples have the potential to identify biomarkers for the refinement of prognosis in addition to clinical variables. Here we utilized proteomics, metabolomics and lipidomics panel assay measurements in baseline plasma samples from the multinational PROVALID study (PROspective cohort study in patients with type 2 diabetes mellitus for VALIDation of biomarkers) of patients with incident or early chronic kidney disease (median follow-up 35 months, median baseline eGFR 84 mL/min/1.73m2, urine albumin-to-creatinine ratio 8.1 mg/g). In an accelerated case-control study, 258 individuals with a stable eGFR course (median eGFR change 0.1 mL/min/year) were compared to 223 individuals with a rapid eGFR decline (median eGFR decline -6.75 mL/min/year) using Bayesian multivariable logistic regression models to assess the discrimination of eGFR trajectories. The analysis included 402 candidate predictors and showed two protein markers (KIM-1, NTproBNP) to be relevant predictors of the eGFR trajectory with baseline eGFR being an important clinical covariate. The inclusion of metabolomic and lipidomic platforms did not improve discrimination substantially. Predictions using all available variables were statistically indistinguishable from predictions using only KIM-1 and baseline eGFR (area under the receiver operating characteristic curve 0.63). Thus, the discrimination of eGFR trajectories in patients with incident or early diabetic kidney disease and maintained baseline eGFR was modest and the protein marker KIM-1 was the most important predictor
The impact of donor and recipient common clinical and genetic variation on estimated glomerular filtration rate in a European renal transplant population
Genetic variation across the HLA is known to influence renalâtransplant outcome. However, the impact of genetic variation beyond the HLA is less clear. We tested the association of common genetic variation and clinical characteristics, from both the donor and recipient, with postâtransplant eGFR at different timeâpoints, out to 5âyears postâtransplantation.
We conducted GWAS metaâanalyses across 10,844 donors and recipients from five European ancestry cohorts. We also analysed the impact of polygenic risk scores (PRS), calculated using genetic variants associated with nonâtransplant eGFR, on postâtransplant eGFR.
PRS calculated using the recipient genotype alone, as well as combined donor and recipient genotypes were significantly associated with eGFR at 1âyear postâtransplant. 32% of the variability in eGFR at 1âyear postâtransplant was explained by our model containing clinical covariates (including weights for death/graftâfailure), principal components and combined donorârecipient PRS, with 0.3% contributed by the PRS. No individual genetic variant was significantly associated with eGFR postâtransplant in the GWAS.
This is the first study to examine PRS, composed of variants that impact kidney function in the general population, in a postâtransplant context. Despite PRS being a significant predictor of eGFR postâtransplant, the effect size of common genetic factors is limited compared to clinical variables
Recurrence of iga nephropathy after kidney transplantation in adults
Background and objectives: In patients with kidney failure due to IgA nephropathy, IgA deposits can recur in a subsequent kidney transplant. The incidence, effect, and risk factors of IgA nephropathy recurrence is unclear, because most studies have been single center and sample sizes are relatively small. Design, setting, participants, & measurements: We performed a multicenter, international, retrospective study to determine the incidence, risk factors, and treatment response of recurrent IgA nephropathy after kidney transplantation. Data were collected from all consecutive patients with biopsy-proven IgA nephropathy transplanted between 2005 and 2015, across 16 âThe Post-Transplant Glomerular Diseaseâ study centers in Europe, North America, and South America. Results: Out of 504 transplant recipients with IgA nephropathy, recurrent IgA deposits were identified by kidney biopsy in 82 patients; cumulative incidence of recurrence was 23% at 15 years (95% confidence interval, 14 to 34). Multivariable Cox regression revealed a higher risk for recurrence of IgA deposits in patients with a pre-emptive kidney transplant (hazard ratio, 3.45; 95% confidence interval, 1.31 to 9.17) and in patients with preformed donorspecific antibodies (hazardratio, 2.59; 95%confidence interval, 1.09 to 6.19).Afterkidneytransplantation,development of de novo donor-specific antibodies was associated with subsequent higher risk of recurrence of IgA nephropathy (hazard ratio, 6.65; 95% confidence interval, 3.33 to 13.27). Immunosuppressive regimen was not associated with recurrent IgA nephropathy in multivariable analysis, including steroid use. Graft loss was higher in patients with recurrence of IgA nephropathy compared with patients without (hazard ratio, 3.69; 95% confidence interval, 2.04 to 6.66), resulting in 32% (95% confidence interval, 50 to 82) graft loss at 8 years after diagnosis of recurrence. Conclusions: In our international cohort, cumulative risk of IgA nephropathy recurrence increased after transplant and was associated with a 3.7-fold greater risk of graft loss
Design and implementation of the international genetics and translational research in transplantation network
Mechanisms underlying human genetic diversity: consequence for antigraft antibody responses
International audienceThis review focuses on the emerging concept of genomewide genetic variation as basis of an alloimmune response. Chronic antibody-mediated rejection is the major cause of long-term graft loss and growing evidence supports the clinical relevance of HLA but also non-HLA related alloimmune responses. Several polymorphic gene products have been identified as minor histocompatibility antigens. The formation of donor-specific alloantibodies is driven by indirect allorecognition of donor-derived peptides representing a form of conventional T-cell response. With the availability of high-throughput sequencing and genotyping technologies, the identification of genomewide genetic variation and thus mismatches between organ donors and graft recipients has become feasible. First clinical data linking genetic polymorphism and clinical outcome have been published and larger studies are currently under way. Protein arrays have successfully been used to identify a large variety of non-HLA antibodies in kidney transplant recipients and the availability of customizable peptide arrays made screening for linear epitopes on an individual patient level feasible. This review provides a summary of the recent findings in histocompatibility matching in the field of solid organ transplantation and complements it with a clear workflow for assessing the impact of genetic differences in protein-coding genes in solid organ transplantation
PLOS ONE / Survival analysis of conservative vs. dialysis treatment of elderly patients with CKD stage 5
Elderly patients represent a growing population among people suffering from ESRD. So far only limited data on actual survival benefits of elderly adults initiating dialysis have been published. Besides the high burden of preexisting comorbidities, dialysis treatment itself may be associated with a further deterioration in functional status in this population. We retrospectively analyzed the Austrian Dialysis and Transplant Registry and identified 8,622 patients who started maintenance hemodialysis after the age of 65 years between 2002 and 2009. We compared this data set to a cohort of 174 patients aged over 65 years with CKD stage 5 who progressed to an eGFR < 10ml/min/ and were managed conservatively in the same era. All patients who died of malignant disease were excluded from this analysis. The risk of mortality was analyzed using multivariable Cox proportional hazards models. Furthermore, a parametric model of time to event analysis was used for visualization of changing risk over time and precise calculation of time to equal risk assuming a Weibull distribution. Hemodialysis treatment was associated with a decreased risk for death with a HR of 0.23 (95% CI 0.18 to 0.29; p<0.001) compared to conservative treatment. The time to event analysis however showed, that although survival was initially superior in the hemodialysis group, hazards crossed thereafter. Time to equal risk was 2.9 months and 1.9 months for female and male patient aged 65, respectively, and decreased to one month in the very elderly aged 95. Elderly patients with ERSD did benefit from initiation of hemodialysis, as the conservative group showed a very high initial mortality rate. This survival benefit of dialysis treatment however did not persist beyond the first two months compared to survivors of the conservative group.(VLID)487411
Durable Anti-SARS-CoV-2 Antibody Response after mRNA-1273 Booster in Peritoneal Dialysis Patients during the Omicron Wave
Anti-SARS-CoV-2 vaccination of dialysis patients has been proven to be safe and effective to reduce COVID-19-related morbidity and mortality. However, data on the durability of anti-SARS-CoV-2 antibodies post-vaccination in peritoneal dialysis (PD) patients are scarce. In this prospective single-center cohort study we measured anti-SARS-CoV-2 RBD antibodies 3 and 6 months after the 3rd dose of the mRNA-1273 vaccine in 27 adult PD patients and recorded breakthrough infections. Furthermore, in a mixed model analysis, we analyzed potential factors influencing the humoral response following vaccination. Anti-SARS-CoV-2 RBD antibody levels declined from 21,424 BAU/mL at 1 month to 8397 BAU/mL at 3 months and to 5120 BAU/mL at 6 months after the 3rd dose, but remained higher than pre-3rd dose levels (212 BAU/mL). Eight patients (29.6%) were infected with SARS-CoV-2 within six months from the 3rd dose during the Omicron wave. Previous high antibody levels, high glomerular filtration rate (GFR) and low Davies Comorbidity Score were associated with higher anti-SARS-CoV-2 antibody levels after the booster. In conclusion, PD patients exhibited a robust and durable humoral response after a third dose of the mRNA-1273 vaccine. A high GFR and low comorbidity as well as previous high antibody levels predicted a better humoral response to vaccination
Novel insights into non-HLA alloimmunity in kidney transplantation
International audienceRecognition of nonâself structures on donor cells represents the main immunological barrier in solid organ transplantation. The human leukocyte antigens (HLA) are considered the most important nonâself (allo)antigens in transplantation. Longâterm graft attrition is mainly caused by the formation of alloreactive antibodies that are directed against nonâself structures (i.e., epitopes) on cell surface proteins. Recently published data provided evidence for a similar importance of nonâHLA mismatches between donors and recipients in acute rejection as well as longâterm kidney allograft survival. These data suggest a broader concept of immunological nonâself that goes beyond HLA incompatibility and expands the current concept of polymorphic nonâself epitopes on cell surface molecules from HLA to nonâHLA targets. Amino acid substitutions caused by single nucleotide variants in proteinâcoding genes or complete loss of gene expression represent the basis for polymorphic residues in both HLA and nonâHLA molecules. To better understand these novel insights in nonâHLA alloimmunity, we will first review basic principles of the alloimmune response with a focus on the HLA epitope concept in donorâspecific antibody formation before discussing key publications on nonâHLA antibodies
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