Journal of Nephrology最新文献

Background: The current definition of acute kidney injury (AKI) using Kidney Disease Improving Global Outcomes (KDIGO) does not account for within-subject biological variation or reference change value (RCV) of serum creatinine (sCr),which may affect its reliability. The aim of this study was to derive and estimate the reference change value of sCr in children and evaluate the impact of using the reference change value-optimized creatinine criteria (KDIGO_RCV) on the burden, severity, and outcome of AKI compared to KDIGO creatinine criteria.

Methods: The reference change value of sCr based on age and initial sCr was derived from data regarding 420 children without risk factors for AKI (derivation cohort). In a cohort of 394 children admitted to the pediatric intensive care unit (PICU) (test cohort), AKI staging was done by KDIGO and KDIGO_RCV. The burden and outcomes of AKI by KDIGO_RCV were compared with AKI, as assessed by KDIGO criteria.

Results: In the derivation cohort (n = 420), our analysis revealed that the younger the age and the lower the sCr, the higher the variability of sCr, with the highest reference change value in the 1 month to 1 year age group (12.1%;median sCr 0.36 mg/dL). In the test cohort (n = 394), the burden of AKI was lower by 15.7% with KDIGO_RCV (n = 102 [25.8%]) compared to KDIGO (n = 163 [41.5%]). Approximately 75% of stage I and 23% of stage II cases of AKI as classified by KDIGO were reclassified as no AKI using KDIGO_RCV. Although cases of AKI classified by KDIGO_RCV were similar in morbidity and mortality to cases of AKI classified by KDIGO, those reclassified as no AKI by KDIGO_RCV (n = 61) had higher morbidity and mortality compared to no AKI by KDIGO (n = 231; p = 0.001).

Conclusion: Reference change value was highest in younger children with lower sCr. While AKI classified by KDIGO_RCV was similar in morbidity and mortality to AKI classified by KDIGO, there is a possibility of missing AKI cases with KDIGO_RCV.

Many studies report that cardiac function is affected by hemodialysis due to alterations in left ventricular morphology and function, particularly left ventricular hypertrophy. Left ventricular hypertrophy is primarily driven by pressure and volume overload, aggravated by factors such as arteriovenous fistulas, anemia, and fluid retention. In addition to left ventricular mass, hemodialysis can impair both left ventricular systolic and diastolic functions, leading to transient reductions in left ventricular ejection fraction, and global longitudinal strain, which are strongly linked to increased mortality. Moreover, chronic dialysis leads to changes in arterial structure and function, including increased intima-media thickness and reduced arterial distensibility, which result in increased afterload. Fluctuating blood pressure during dialysis further affects cardiac function, emphasizing the need for comprehensive assessment of both ventricular and arterial functions, a relationship defined as ventriculo-arterial coupling. In patients with kidney failure, ventriculo-arterial coupling serves as a valuable load-independent prognostic marker, enhancing risk prediction and stratification. Non-invasive tools like echocardiography and speckle-tracking techniques are currently available for evaluating these parameters, enabling early detection and intervention to mitigate cardiovascular risks in patients with kidney failure undergoing hemodialysis. These insights highlight the complex interplay between fluid management, left ventricular function, and arterial stiffness, emphasizing the importance of improved strategies to optimize cardiovascular outcomes in this high-risk population.

Background: More liberal use of iron therapy is favored in dialysis patients based on lower erythropoietin need and clinical outcomes. However, it remains unclear whether higher iron stores are associated with better patient-reported outcomes. We assessed the longitudinal associations of ferritin and transferrin saturation (TSAT) levels with patient-reported outcomes in incident dialysis patients.

Methods: This prospective cohort study included incident dialysis patients who had completed at least one patient-reported outcome questionnaire and had undergone a laboratory assessment (e.g., ferritin, transferrin saturation, hemoglobin) within the first year of dialysis. The primary outcome was health-related quality of life (HRQoL), measured using the 12-Item Short Form (SF-12) survey. Secondary outcomes were the presence of anemia-related symptoms, measured using the Dialysis Symptom Index. We used sequential conditional mean models to adjust for baseline and time-varying confounding.

Results: We included 1069 incident dialysis patients, of whom 76% initiated hemodialysis. The mean (SD) age was 64.0 (14.2) years and 34% were female. Over a 1-year follow-up, patients with ferritin levels < 200, > 500 - 700, and > 700 ng/mL did not have a significantly different HRQoL compared to those with levels between 200 - 500 ng/mL, chosen as reference. Similarly, patients with TSAT levels < 20 or ≥ 40% did not have a significantly different HRQoL compared to those with levels between 20 - 39%. No significant differences were found in the odds of experiencing fatigue, shortness of breath, muscle cramps or restless legs between the ferritin and TSAT groups.

Conclusion: Differences in iron status parameters were not associated with differences in patient-reported outcomes during the first year of dialysis. Our findings therefore suggest that decisions on iron therapy should be guided by target hemoglobin levels and clinical outcomes in dialysis patients.

Background: Chronic kidney disease (CKD) affects 6-10% of adults and often remains undiagnosed until advanced stages, leading to inadequate management. This study compared diagnosed, proxy-diagnosed, and undiagnosed CKD patients regarding prevalence, clinical assessment, nephroprotective treatment, healthcare utilization, and mortality.

Methods: This retrospective observational study analyzed Region Halland's healthcare data for adults meeting KDIGO CKD-confirmed criteria for the year 2019. Patients were categorized as diagnosed CKD (ICD-coded), proxy-diagnosed CKD (CKD-related diagnoses), or undiagnosed CKD (meeting CKD criteria without an ICD CKD diagnosis).

Results: Of 20,488 CKD patients, 21% had diagnosed CKD, 18% proxy-diagnosed CKD, and 61% undiagnosed CKD. Mean ages were 76.4, 62.4, and 81.8 years, respectively (p < 0.001). Blood pressure follow-up was carried out in diagnosed CKD (88%) versus 67% and 80% in the proxy-diagnosed and undiagnosed groups. eGFR was tested in 66% overall (73% diagnosed, 53% proxy-diagnosed, 66% undiagnosed), while urine albumin-to-creatinine ratio (UACR) testing was performed in 27% overall (50%, 20%, and 21%, respectively). Renin-angiotensin system inhibitors were prescribed to 45% overall (51%, 28%, and 47%, respectively). The adjusted hospitalization risk was 2.71 (CI: 2.59-2.84) in diagnosed CKD and 1.38 (CI: 1.31-1.46) in proxy-diagnosed CKD. Adjusted all-cause mortality hazard ratios were 2.22 (CI: 1.95-2.52) and 1.31 (CI: 1.08-1.60), respectively. Stratified sensitivity analyses by CKD stage confirmed these associations, though the strength varied.

Conclusions: Patients with complex comorbidities, more advanced CKD, and frequent hospitalizations are more likely to be diagnosed with CKD and receive better follow-up care. Proxy-diagnosed CKD was common and associated with suboptimal management. These findings emphasize the need for consistent and accurate CKD identification to improve outcomes and optimize care.

Background: There are unexplained sex differences regarding prevalence, morbidity, and mortality in chronic kidney disease (CKD). Of note, females are less likely to be waitlisted and experience longer waiting times for kidney transplant (KTx). Recently, interest in cognitive impairment among CKD patients has increased due to its potential negative impact on therapeutic outcomes. This study aimed to investigate the influence of sex on cognitive impairment prevalence and patterns, as well as modifiable dementia risk factors, in KTx recipients.

Methods: This cross-sectional study screened KTx recipients for cognitive impairment using the Mini-Addenbrooke's Cognitive Examination. Demographic data, medical histories, and laboratory results were collected from medical records.

Results: The study included 126 consecutive KTx recipients, predominantly male (62%). Males showed higher serum creatinine (1.57 vs. 1.25 mg/dL; p = 0.001), urea (59.50 vs. 55.00 mg/dL; p = 0.046), and uric acid (7.20 vs. 6.20 mg/dL; p = 0.012) levels compared to females. However, creatinine clearance rates did not differ significantly between sexes (49.03 ± 20.29 vs. 50.79 ± 21.7 mL/min/1.73 m²; p = 0.645). A non-significant trend toward higher smoking prevalence among males was observed (p = 0.054). Cognitive impairment prevalence in the overall cohort was 23%, with no significant sex difference (males: 23.1%, females: 22.9%).

Conclusions: There was a high prevalence of cognitive impairment among KTx recipients, affecting both sexes equally. Male predominance in the study cohort likely reflects systemic disparities in transplant access. These findings highlight the importance of integrating sex-specific considerations into the management and follow-up care of KTx recipients.

Background: The available literature on graft histology and graft outcomes in kidney transplant recipients (KTRs) with acute rejection after ABO-incompatible and ABO-compatible kidney transplant is scarce.

Methods: Among 100 ABO-incompatible kidney transplants (KTx) performed between 2014 and 2019, 37 (37%) developed biopsy-proven acute rejection. A matched cohort of 37 ABO-compatible KTRs with biopsy-proven acute rejection was identified from 97 (7%) patients with biopsy-proven acute rejection, among 680 ABO-compatible KTRs. Matching employed a propensity score using donor age, donor sex, donor GFR, induction agent, HLA mismatch, and maintenance treatment with tacrolimus. The individual BANFF scores [acute (g,i,t,ptc,v) and chronic (ci,ct,cg, cv) scores], and mean BANFF scores between the two groups were compared. We estimated survival in the matched-pairs cohort according to Kaplan-Meier and compared the two groups using the log-rank test.

Results: Acute rejection occurred in the early post transplant phase in 29 (78%) vs. 17 (46%) (P = 0.008), and late in 8 (22%) vs. 20 (54%) (P = 0.008) in ABO-incompatible KTRs and ABO-compatible KTRs, respectively. The mean BANFF scores were similar in ABO-incompatible and ABO-compatible KTRs except for interstitial inflammation, which was significantly higher in ABO-compatible KTRs (1.43 ± 0.728 vs. 1.11 ± 0.516, p = 0.030). The response to antirejection therapy was similar in the two groups. Post-rejection graft survival was significantly shorter in ABO-incompatible KTRs than in ABO-compatible KTRs (80% vs. 92% at one year and 63% vs. 92% at three years (log-rank p = 0.017)).

Conclusion: There were no significant differences between ABO-compatible and ABO-incompatible KTRs in mean BANFF scores in patients with biopsy-proven acute rejection after propensity score-matching except for interstitial inflammation. Post-rejection graft survival was inferior in ABO-incompatible KTRs.

Background: Disruption of the gut microbiota in kidney transplant recipients has been linked to an increased risk of post-transplant infections and gastrointestinal symptoms, including diarrhoea. Dietary supplementation with resistant starch may mitigate these risks by promoting the growth of commensal gut bacteria that produce beneficial bioactive metabolites.

Methods: Faecal microbiome profiles, gastrointestinal symptoms, and dietary habits were assessed in 13 individuals with kidney failure before and after transplantation, using 16S rRNA V4 amplicon sequencing, a modified Gastrointestinal Symptom Rating Scale (mGSRS) and a food frequency screener. The effect of resistant starch supplementation on the gut microbiota pre- and post-transplant was evaluated using a preclinical in vitro fermentation model with high amylose maize starch.

Results: Gut microbiota diversity (based on richness and Shannon diversity index) declined significantly following kidney transplantation. This loss correlated with a higher frequency of gastrointestinal symptoms, including rectal pain. Significant shifts in microbiota composition were observed, including depletion of butyrate-producing Lachnospiraceae species, a change previously associated with post-transplant diarrhoea. These microbiota changes occurred independently of dietary patterns, which remained consistent throughout the study. Fermentation of high amylose maize starch in vitro by pre- or early post-transplant gut microbiota did not result in significant expansion of commensal bacterial populations.

Conclusions: Alterations in the gut microbiota following kidney transplantation are associated with gastrointestinal symptoms. High amylose maize starch supplementation did not produce beneficial effects on the gut microbiota in preclinical model studies, either before or after transplantation.

Background: Chronic kidney disease (CKD) represents a major global health burden, often diagnosed at advanced stages when treatment is less effective. Albuminuria, assessed by the urine albumin-to-creatinine ratio (uACR), is a key biomarker for CKD detection and risk stratification. Despite guideline recommendations, adherence to uACR testing remains low, limiting early diagnosis and timely referral. The ALLIANCE project aimed to develop a multidisciplinary consensus on optimizing uACR testing and referral pathways for improved CKD management in at-risk populations.

Methods: A modified nominal group technique was used to achieve expert consensus. Seven nephrologists and eight specialists in other disciplines  (cardiologists, endocrinologists, diabetologists, and a clinical biochemist) participated in structured discussions and ranked statements across three domains: (1) at-risk population definition, (2) barriers to uACR testing, and (3) CKD management and referral. Relevance rankings were analyzed using hierarchical clustering.

Results: Twenty-seven consensus statements were developed, eight of which were deemed highly relevant. Key recommendations included expanding CKD risk awareness to encompass obesity and family history, enhancing clinician education, and improving coordination between nephrologists and other specialists. Early nephrology referral was emphasized for patients with marked albuminuria, rapid renal decline, or specific risk factors. Integration of digital health tools, including shared electronic health records, was advised to support coordinated care.

Conclusions: The ALLIANCE project identified critical gaps in CKD detection and management. Addressing these through clinician education, standardized uACR testing protocols, and multidisciplinary collaboration may improve outcomes and reduce cardiorenal risk. Implementation of these consensus recommendations could facilitate earlier diagnosis and better management of high-risk patients.

Background: The primary challenge for hemodialysis (HD) patients using permanent tunneled cuffed catheters is to prevent catheter-related bloodstream infections. This study assessed the effectiveness of sodium bicarbonate in preventing catheter-related bloodstream infections and compared its efficacy to antibiotic-containing locks.

Design, materials, and methods: We conducted a prospective single-center, open-label, cohort study over 30 months with the aim to compare three cohorts: cohort I employed 8.4% sodium bicarbonate solution lock, cohort II employed 0.5 mg/ml gentamicin/acid citrate dextrose solution lock, and cohort III employed unfractionated conventional heparin 5000 U/ml solution lock. The primary endpoint was the first episode of catheter-related bloodstream infection, while the secondary endpoint was catheter loss due to catheter-related bloodstream infection.

Results: This study involved 204 HD patients with permanent tunneled cuffed central venous catheters (CVCs). A total of 58 cases of catheter-related bloodstream infection were documented. In the sodium bicarbonate-lock cohort, infection occurred in 17.24%, in the gentamicin/acid citrate-lock cohort in 36.21%, and in the heparin-lock cohort in 46.55%. Patients with sodium bicarbonate and gentamicin/acid citrate locks exhibited a statistically significant lower risk of developing infections (0.4/1000 catheter days and 0.7/1000 catheter days, respectively) compared to patients with heparin-lock (1.4/1000 catheter days). Patients with heparin lock faced a higher risk of losing a catheter due to infection compared to those with gentamicin/acid citrate lock and sodium bicarbonate-lock (Hazard Ratio (HR) = 1.26, 95% Confidence Interval (CI) [1.09-1.46], P = 0.001) and (HR = 1.10, 95% CI [1.01-1.19], P = 0.024).

Conclusion: The sodium bicarbonate locking solution demonstrated an infection-free catheter survival comparable to that of the gentamicin citrate solution and significantly decreased catheter-related bloodstream infection compared to heparin locks.