Kidney Research and Clinical Practice最新文献

Early identification of kidney disease can protect kidney health, prevent kidney disease progression and related complications, reduce cardiovascular disease risk, and decrease mortality. We must ask "Are your kidneys ok?" using serum creatinine to estimate kidney function and urine albumin to assess for kidney and endothelial damage. Evaluation for causes and risk factors for chronic kidney disease (CKD) includes testing for diabetes mellitus and measurement of blood pressure and body mass index. This World Kidney Day, we assert that case-finding in high-risk populations, or even population-level screening, can decrease the burden of kidney disease globally. Early-stage CKD is asymptomatic, simple to test for, and recent paradigm-shifting CKD treatments such as sodium glucose co-transporter-2 inhibitors dramatically improve outcomes and favor the cost-benefit analysis for screening or case-finding programs. Despite this, numerous barriers exist, including resource allocation, healthcare funding, healthcare infrastructure, and healthcare-professional and population awareness of kidney disease. Coordinated efforts by major kidney non-governmental organizations to prioritize the kidney health agenda for governments and to align early detection efforts with other current programs will maximize efficiencies.

Hyperuricemia is frequently observed in patients with chronic kidney disease and is recognized as a significant contributor to the progression of renal dysfunction. On the other hand, hypouricemia, although less thoroughly studied, has been implicated in exercise-induced acute kidney injury and urolithiasis. Uric acid (UA), the final product of purine metabolism, is predominantly synthesized in the liver and excreted through both renal and intestinal pathways. The metabolism and excretion of UA are intricately linked to kidney function, underscoring their clinical significance in the context of renal disease. This review provides a comprehensive review of UA metabolism and the key urate transporters, including URAT1, GLUT9, OATs, and ABCG2, which play pivotal roles in maintaining UA homeostasis. Additionally, this review discusses the genetic and environmental factors that influence UA regulation, with a particular focus on the pathological consequences of transporter dysfunction. By elucidating the mechanisms underlying UA handling in the renal and intestinal systems, this review aims to enhance our understanding of UA-related pathophysiology, and to inform the development of targeted therapeutic strategies for modulating UA transport.

Background: The continuous rise in healthcare costs associated with hemodialysis has become a growing concern in South Korea, where hemodialysis is the predominant treatment modality for end-stage kidney disease. Currently, all dialyzers are imported, underscoring the need for domestically manufactured alternatives. This study aims to evaluate the clinical efficacy and safety of a domestically produced novel polyethersulfone dialyzer.

Methods: This multicenter, randomized, crossover clinical trial evaluated the non-inferiority of the Synoflux series dialyzer (Synopex Inc.) compared to the commercially available FX Classix dialyzer (Fresenius Medical Care) in maintenance hemodialysis patients. Each patient was randomly assigned to one of two treatment sequences, receiving each dialyzer for 4 weeks in a crossover design. The primary endpoints were the urea reduction ratio (URR) and single-pool Kt/V (spKt/V). Secondary endpoints included the clearance of middle molecules and safety outcomes.

Results: The Synoflux series dialyzer met the non-inferiority criteria for both URR (mean difference, -1.29%; 95% confidence interval [CI], -2.01 to -0.58) and spKt/V (mean difference, -0.06; 95% CI, -0.10 to -0.02). It demonstrated superior clearance of middle-molecule solutes, including cystatin C, β2-microglobulin, and prolactin. No serious adverse events related to the dialyzer were reported, and the frequency of hypotension or clotting events was comparable between the dialyzers.

Conclusion: The Synoflux series dialyzer demonstrated non-inferior efficacy and acceptable safety compared to the widely used FX Classix dialyzer, thereby supporting its clinical applicability as a domestically produced alternative for maintenance hemodialysis.

Background: The clinical implications of genetic risk for hypertension (HTN) and high low-density lipoprotein cholesterol (LDL-C) levels in incident chronic kidney disease (CKD) are unknown. This study aimed to examine whether polygenic risk scores (PRSs) for these two factors can predict the development of CKD.

Methods: We included 245,893 participants enrolled in UK Biobank during 2006-2010 and followed up until 2022. The primary exposures were the PRS for HTN (PRS HTN) and high LDL-C concentration (PRS LDL-C). The primary outcome was incident CKD, assessed using cause-specific competing-risk models.

Results: During a median follow-up of 13.7 years (interquartile range, 13.0-14.3 years), 7,771 individuals experienced CKD. A 1-standard deviation higher PRS HTN was associated with a 7% higher risk of incident CKD (hazard ratio [HR], 1.07; 95% confidence interval [CI], 1.05-1.10). However, PRS LDL-C showed no significant association with incident CKD. In a combined association analysis based on the four groups classified by the median values of PRS, the HRs were 1.03 (95% CI, 0.97-1.10) in the high LDL-C-risk group and 1.13 (95% CI, 1.06-1.20) in both the high HTN group and the combined high-risk group, compared with the reference group.

Conclusion: This study showed that individuals with a higher genetic predisposition to HTN were more likely to develop CKD than those predisposed to a high LDL-C concentration. Additionally, higher genetic predispositions for these two factors did not synergically contribute to the risk of CKD.

Background: Hypertension is a leading cause of cardiovascular mortality in patients with end-stage kidney disease, with 80% to 90% of dialysis patients affected. Many patients with hypertension exhibit a non-dipper blood pressure pattern that is influenced by various factors. This study investigated the relationship between blood pressure patterns, volume status, vascular diseases, and oxidative stress markers.

Methods: Forty-nine hemodialysis patients underwent 24-hour ambulatory blood pressure monitoring and were classified into "dipper" and "non-dipper" blood pressure groups. Laboratory tests, bioimpedance analysis, carotid ultrasound, and ankle-brachial index (ABI) measurements were performed, including baseline myeloperoxidase (MPO) and fetuin-A level assessments.

Results: Eleven patients were classified as dippers and 38 as non-dippers. The non-dipper group exhibited higher nighttime systolic blood pressure, consistent with their lack of nocturnal blood pressure decline. Further, this group had significantly elevated MPO levels (2.5 ng/mL vs. 1.5 ng/mL, p = 0.03) and accounted for all recorded deaths. No significant differences were found between the two groups regarding volume status, intima-media thickness, carotid artery calcification, or ABI.

Conclusion: Most hemodialysis patients exhibited a non-dipper pattern, which was significantly associated with increased MPO levels, suggesting a role of oxidative stress. There was no significant association with fluid overload, peripheral arterial disease, or vascular calcification. Further research is needed to explore the impact of oxidative stress on the non-dipper pattern in the hypertensive hemodialysis population.

Background: The clinical significance and renal outcomes of C1q nephropathy (C1qN) are unclear; therefore, the implications of C1qN as a new pathological entity are uncertain. We compared the clinical characteristics of glomerulonephritis reclassified into cases that meet the definition of C1qN and glomerulonephritis not included in the definition of C1qN.

Methods: In total, 21,697 patients who underwent native kidney biopsy at 18 hospitals throughout Korea between 1979 and 2018 were retrospectively enrolled. A total of 77 patients were selected from the group that met the definition of C1qN after reclassification; however, six patients were excluded because of secondary systemic disease. Characteristics of pathological findings classified into C1qN, without C1q stain, and with nondominant C1q stain that did not fulfill the criteria for C1qN were compared.

Results: No differences in clinicopathological findings and incidence of ESRD were evident (matched by age and sex) between glomerulonephritis cases reclassified into the group that met the definition of C1qN and those without C1q staining. Decreased proteinuria in patients with membranous nephropathies reclassified into the group that met the definition of C1qN was the only significant finding. Immunoglobulins showed higher intensity on immunofluorescence staining of the group that met the definition of C1qN. Additionally, C3 intensity was higher in reclassified immunoglobulin A nephropathy and membranous nephropathies.

Conclusion: Overall, reclassification into the group that met the definition of C1qN did not indicate a different clinicopathological identity. C1q activation and presumed classical complement pathway activation in kidney tissues in C1qN could not be confirmed. Hence, further studies are needed.

Background: Albuminuria is one of the factors promoting the progression of chronic kidney disease (CKD). The study aimed to assess the efficacy and safety of calcitriol for the reduction of microalbuminuria in patients with nondiabetic nephropathy.

Methods: In this randomized, double-blind, placebo-controlled, and multicenter study, adult patients with nondiabetic CKD stage 3 or greater and albuminuria were included. Participants were administered calcitriol or placebo for 6 months and followed for up to 12 months. The primary outcome was the change in urine protein-to-creatinine ratio (UPCR), and secondary outcomes included the changes in renal function and vitamin D level. The safety was assessed by recording adverse events during the treatment and follow-up.

Results: A total of 159 subjects were enrolled. The UPCR at 24 and 48 weeks was significantly decreased compared to the baseline in the calcitriol group (ΔUPCR, -0.24 g/g [95% CI, -0.43 to -0.05] and -0.22 g/g [95% CI, -0.43 to -0.01], respectively), but the mean changes of UPCR during 24 weeks and 48 weeks were no significant difference between the two groups. No significant differences were in the change in renal function and vitamin D level. Seventy-eight adverse events were reported during the treatment phase, and there were no significant differences in the type or frequency of adverse events between the two groups.

Conclusion: Although calcitriol treatment showed a significant reduction of proteinuria from baseline, the effect was insufficient in nondiabetic CKD compared to placebo. Therefore, the use of calcitriol for the reduction of albuminuria is worth considering.

Background: How weekend catch-up sleep (WCS) influences chronic kidney disease (CKD) risk is unknown. We investigated the association between WCS and CKD prevalence in adults.

Methods: In the National Health and Nutrition Examination Survey (NHANES, 2017-2020) participants (n = 4,961; age ≥ 40 years), we assessed the relationships of WCS (>1 hour increased sleep duration on weekends) with CKD and albuminuria prevalence via multivariate logistic regression analysis adjusted for potential confounders.

Results: WCS participants exhibited notably both lower CKD and albuminuria prevalence than non-WCS participants did, even after confounding variable adjustment (adjusted odds ratio [OR], 0.67; 95% confidence interval [CI], 0.46-0.96 and OR, 0.69; 95% CI, 0.49-0.97, respectively). Specifically, 1 to 2 hours of WCS were associated with decreased CKD (OR, 0.58; 95% CI, 0.38-0.89; p = 0.02). Furthermore, 1 to 2 hours of WCS were also significantly associated with lower albuminuria (OR, 0.11; 95% CI, 0.05-0.22; p < 0.001) among individuals sleeping <6 hours on weekdays.

Conclusion: WCS, particularly 1 to 2 hours, was significantly associated with a lower CKD prevalence in the middle-aged and older population, and albuminuria risk among those with restricted weekday sleep. These findings suggest that maintaining adequate sleep duration through WCS is linked to beneficial effects on kidney health. Longitudinal studies are needed to confirm these results.