Journal of Nephrology最新文献

Background: While electrical muscle stimulation during hemodialysis has been reported to improve physical performance in middle-aged patients, clinical evidence regarding its efficacy in older patients with frailty remains limited.

Methods: In this crossover trial, we randomly assigned 18 older patients (aged ≥ 65 years) with frailty receiving maintenance hemodialysis in a 1:1 ratio to the study intervention. Group 1 underwent electrical muscle stimulation first, followed by a five-week washout period, and then the control session without electrical muscle stimulation. Group 2 received the control session first, followed by the electrical muscle stimulation sessions. Eligible patients had physical frailty defined by a Short Physical Performance Battery (SPPB) score of 4-9 points. Electrical muscle stimulation was conducted for 30-40 min per day, 3 days a week, over 5 weeks, during hemodialysis sessions. The primary outcome was the difference in quadriceps isometric strength before and after the treatment period.

Results: Among 18 patients who were randomized, 16 patients were included in the intention-to-treat analysis (median age: 76 years [Q1 to Q3, 72 to 79]; men: 38%; median SPPB: 6 points [Q1 to Q3, 5 to 9]). The median change in quadriceps isometric strength (Q1 to Q3) was 1.5%dry weight (%DW) (0.2 to 4.2) during the electrical muscle stimulation intervention period and - 3.6%DW (- 7.7 to - 1.6) during the control period (P = 0.0027).

Conclusions: Our trial found that intradialytic electrical muscle stimulation was associated with improved quadriceps isometric strength in older patients with frailty, indicating a potential benefit of intradialytic electrical muscle stimulation intervention for physical performance, also in these subjects.

Trial registration: The study was registered in a public trial registry (UMIN-CTR, number: UMIN000032501).

Background: Acute kidney injury (AKI) is a common complication in patients affected by COVID-19 and has been strongly associated with increased mortality. However, its independent contribution remains debated. This study aimed to evaluate the independent association using a directed acyclic graph-based approach.

Methods: Retrospective, multicenter cohort study in Medellín, Colombia, from June 2020 to April 2022. AKI was defined according to KDIGO criteria. A directed acyclic graph was constructed to map the hypothesized causal relationship between AKI and mortality, integrating evidence from a comprehensive literature review and expert´s consensus. A Poisson regression model with robust variance was applied to estimate adjusted incidence rate ratios (IRRs) for mortality.

Results: A total of 1722 patients were included, of whom 30.7% developed AKI. Mortality was higher among patients with AKI (58.1% vs. 19.6%). A directed acyclic graph was used to identify a minimal sufficient adjustment set for confounding control. After adjustment, the IRRs for in-hospital mortality were 1.25 (95% CI: 1.09-1.43) for stage 1, 1.62 (95% CI: 1.35-1.93) for stage 2, and 1.64 (95% CI: 1.46-1.85) for stage 3.

Conclusions: AKI is independently and significantly associated with an increased risk of mortality in COVID-19 patients. This study makes a novel contribution by applying directed acyclic graphs to enhance causal inference. Directed acyclic graphs provide a rigorous framework for identifying true confounders and avoiding inappropriate adjustment for mediators, thereby reducing bias and improving the validity of causal estimates. In clinical settings where randomized controlled trials are not feasible, the use of directed acyclic graphs represents a robust alternative for exploring causal relationships.

Background: Kidney stone formation is driven by an imbalance between lithogenic substances and crystallization inhibitors. Current guidelines recommend a 24-h urine collection in patients with kidney stone disease to assess the risk of stone formation and monitor therapy compliance. However, real-world data on adherence to these guidelines remain limited and outdated.

Methods: We used the Health Search Database to examine laboratory test data of patients with kidney stone disease between 2013 and 2022 in Italy. Adults with at least one episode of kidney or ureteral stones during this period were included. We used the prescription of urinary calcium, oxalate, and citrate levels as a proxy for full metabolic testing.

Results: A total of 21,907 adult patients were identified (44.6% women). Only 4.8% (n = 1059) underwent 24-h urine testing, and just 0.6% had all three target measurements. Testing rates were slightly higher in recurrent stone formers (6.1%). The likelihood of receiving a test increased nearly sixfold after a nephrology visit (OR 6.09, 95% CI 5.27-7.05, p < 0.001), compared to a lower increase after urology visits (OR 1.95, 95% CI 1.71-2.23, p < 0.001). Nonetheless, fewer than 10% of kidney stone disease patients consulted a nephrologist, and only half of those with coexisting chronic kidney disease (CKD) had such a referral.

Conclusion: Awareness of 24-h urine testing and nephrology referral in stone formers remains low, despite their role in guiding personalized treatment. Promoting their use could enhance patient care by identifying urinary abnormalities and reducing the risk of recurrence and complications.

Nephrotic syndrome is a rare complication of allogeneic haematopoietic stem cell transplantation (alloHSCT). Its pathogenesis is not fully understood. Membranous nephropathy and minimal change disease are the most common causes of nephrotic syndrome. Nephrotic syndrome occurs more frequently in people with chronic graft-versus-host disease (GvHD). Glucocorticosteroids and cyclosporine are the most common treatments, but their use is associated with the risk of side effects and variable responses. We present a case of a patient after alloHSCT with advanced GvHD who developed nephrotic syndrome resistant to immunosuppressive treatment. Additionally, when her kidney function deteriorated, she required kidney replacement therapy. We would like to emphasise the importance of kidney biopsy as a tool for determining the extent of kidney damage and the possible response to therapy.

Background: Adenine phosphoribosyltransferase (APRT) deficiency is a rare, inherited metabolic disorder characterized by abundant urinary excretion of 2,8-dihydroxyadenine (DHA), causing urinary stones and chronic kidney disease. The aim of this study was to examine the effect of allopurinol and febuxostat on plasma levels and urinary excretion of DHA in individuals with APRT deficiency.

Methods: Adult individuals enrolled in the Icelandic APRT Deficiency Registry were invited to participate in a single-center, open-label, crossover, randomized clinical trial comparing the effect of allopurinol 400 mg/day and 800 mg/day and febuxostat 40 mg/day and 80 mg/day on plasma concentration and urinary excretion of DHA.

Results: Of 12 participants who initiated the study, 7 (3 females) completed the trial; median (range) age 57.7 (37.3-65.1) years. Off pharmacotherapy, the median plasma DHA was 300 (178-1315) ng/mL. In individuals taking allopurinol 400 mg/day and 800 mg/day, the median plasma DHA was 25 (below the limit of detection [LOD]-95) ng/mL and below the limit of detection (< LOD-92) ng/mL, respectively. On febuxostat 40 mg/day, the median plasma DHA was below the limit of detection (< LOD-35) ng/mL and on 80 mg/day DHA was below the limit of detection in all samples tested. The median urine DHA-to-creatinine ratio was 8.18 (6.21-18.69) mg/mmol off pharmacotherapy and 1.90 (< LOD-4.52) mg/mmol and 0.35 (< LOD-4.32) mg/mmol on allopurinol 400 mg/day and 800 mg/day, respectively. During treatment with febuxostat 40 mg/day and 80 mg/day, the urine DHA-to-creatinine ratio was 0.54 (< LOD-1.33) mg/mmol and below the limit of detection (< LOD-0.64) mg/mmol, respectively.

Conclusions: The plasma concentration and urinary excretion of DHA decreased markedly on treatment with both study drugs, although febuxostat was more efficacious than allopurinol in both prescribed doses. Trial registration number and date of registration. EudraCT No. 2021-002185-40; https://www.clinicaltrialsregister.eu/ctr-search/search?query=Research+Registry Date on which this record was first entered in the EudraCT database: 2019-03-19.

Background: Chronic kidney disease (CKD) is a common comorbidity among patients with tricuspid regurgitation, yet its impact on tricuspid regurgitation outcomes is underexplored. This study examines how CKD affects the relationship between severe tricuspid regurgitation and overall survival.

Methods: This is a retrospective cohort study of all adult patients (> 18 years old) evaluated at the Sheba Medical Center, between 2007 and 2022, who underwent transthoracic echocardiographic evaluation. It is based on the SHEBAHEART big data registry. Sheba Medical Center is the largest hospital in Israel with approximately 115,000 admissions per year. The echocardiographic reports together with the electronic medical records of all patients are the source for this study. Patients with missing creatinine data within one month of their echocardiography study, as well as those who underwent tricuspid regurgitation intervention, were excluded from the study. Patients were categorized into four groups, according to the presence and severity of tricuspid regurgitation and stratified by CKD stage. The primary outcome was all-cause mortality.

Results: The study included 78,147 patients (median age 67, IQR 55-78), with 2989 (4%) having severe tricuspid regurgitation and 19,910 (25%) with an estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m². Over a median 4-year follow-up, 28,112 patients (36%) died. Both tricuspid regurgitation severity and CKD stage were associated with increased mortality risk (log-rank p < 0.001 for both). Adjusted models showed that compared to the none/trivial group, patients with mild, moderate, and severe tricuspid regurgitation had a 6%, 12%, and 35% higher risk of death, respectively (p < 0.001 for all). The association of tricuspid regurgitation with poor survival was CKD-dependent, with increased mortality risk of 56% vs. 23% among patients with eGFR < 60 vs. eGFR ≥ 60 (p for interaction < 0.001). The interaction analysis was no longer significant when right ventricular function was incorporated into the multivariable model. Subanalysis, limited to patients with isolated tricuspid regurgitation, yielded consistent results.

Conclusions: The association between severe tricuspid regurgitation and poor survival is stronger in advanced CKD patients and may be modulated through right ventricular function.

Background: Significant differences in kidney disease-related mortality persist among Italian regions, even after adjusting for age and education level, suggesting a role of contextual factors. The study aimed to assess whether these differences are attributable to the availability of economic and structural resources for healthcare.

Methods: Retrospective longitudinal cohort study conducted on the Italian population recorded in the 2011 Census and followed up to 2019. Deaths from kidney diseases were retrieved by record linkage with the Causes of Death Register. Regional information on age-adjusted prevalence of kidney disease (indicator of demand for care), current healthcare expenditure per capita, and number of nurses and beds in dialysis units (indicators of renal care supply) per million residents were selected as contextual variables. Regional differences in kidney disease-related mortality taking or not into account these contextual indicators were evaluated using a multilevel approach.

Results: Age-adjusted kidney disease-related mortality rates were higher than the national average for males and females in the largest southern regions. When adding to the models the prevalence of kidney disease, healthcare expenditure, and number of nurses and beds in dialysis units, regional differences in kidney disease-related mortality became non-significant compared to the national average. Significant heterogeneity persisted across regions, both in males and females, although its magnitude strongly decreased when regional-level covariates were considered.

Conclusions: Regional differences in kidney disease-related mortality decreased markedly after considering the general expenditure for healthcare and the number of nurses in dialysis units, suggesting that resources dedicated to caring for kidney disease patients may play an important role in decreasing their mortality.

Background: Arteriovenous fistulas (AVF) and arteriovenous grafts (AVG) are the preferred options for establishing vascular access in adult patients undergoing haemodialysis treatment. Although various official recommendations exist for AVF and AVG cannulation, a comprehensive, personalised approach to cannulation has yet to be proposed. This systematic review highlights existing knowledge gaps and identifies best practices by synthesising quality evidence on all components involved in AVF and AVG cannulation for haemodialysis.

Methods: A search was conducted across the PubMed, CINAHL, Cochrane, Scopus and Web of Science databases for studies published between January 2016 and January 2023. This review followed the PRISMA statement and was registered with PROSPERO (CRD42024293288).

Results: Twenty-four studies met the inclusion criteria and reported outcomes for 11,687 patients and 801 ward staff in 14 countries. Collectively, their results emphasized a person-centred approach, the importance of nurses' and patients' skills, and the need for continuous learning to enhance patient care. While recommendations varied, the implementation of the button-hole technique and innovative nurse-led devices such as plastic cannulas and point-of-care ultrasound guided cannulation were highly recommended.

Conclusion: This systematic review highlights the importance of adopting a person-centred approach to managing patients undergoing haemodialysis. It also recommends the systematic assessment of vascular access and the continuous training for nurses and patients. Further research is needed to evaluate the cost-effectiveness of innovative, nurse-led tools in haemodialysis units.

Background: Transplant arteriopathy involves a spectrum of Leukocyte Common Antigen-positive, hypoelastotic, foam cell intimal fibrosis. Transplant arteriopathy has been associated with both Chronic Active T Cell-Mediated Rejection and Antibody-Mediated Rejection chronicity. Aim of this study was to find clinicopathological correlates of transplant arteriopathy in a single centre retrospective cohort.

Methods: We retrieved 46 biopsies showing transplant arteriopathy from 33 patients, out of a total of 784 biopsies carried out between 2005 and 2014. We retrospectively evaluated Banff Lesion Scores and Additional Diagnostic Parameters as well as the transplant arteriopathy descriptors Leukocyte Common Antigen-positive, hypoelastotic, foam cell, and correlated these findings with clinical data and death-censored transplant survival.

Results: Transplant arteriopathy was frequently associated with antibody-mediated rejection-associated Banff Lesions Scores and Additional Diagnostic Parameters. Hypoelastotic, leukocyte common antigen-positive and foam cell lesions were often combined, with hypoelastotic lesion being the most frequent finding in transplant arteriopathy. Leukocyte common antigen-positive lesion appeared earlier and was associated with Banff Lesion Score v ≥ 1. About half were positive for donor-specific antibodies, about a third had concurrent transplant glomerulopathy, and about a sixth were C4d-positive. Twelve of thirty-three transplants were lost during follow-up, concurrent transplant glomerulopathy was associated with shorter transplant survival.

Conclusions: The frequent coincidence of transplant arteriopathy and indicators of antibody-mediated rejection suggests that this arterial remodelling could indeed be antibody-mediated rejection chronicity. The transplant community should re-examine transplant arteriopathy with an expanded definition including the previously ignored hypoelastotic lesion in order to re-confirm or reject with confidence transplant arteriopathy as Additional Diagnostic Parameter of Antibody-Mediated Rejection chronicity, and to learn about its prognostic and therapeutic implications.