Search Results (956)

Accumulating evidence suggests that exposure to pollution from environmental cadmium (Cd) contributes to diabetic kidney disease as indicated by albuminuria and a progressive decrease in the estimated glomerular filtration rate (eGFR). This study examined the effects of Cd exposure on eGFR and the excretion rates of albumin (E_alb) and β₂-microglobulin (E_β2M) in 65 diabetics and 72 controls. Excretion of Cd (E_Cd) was a measure of exposure, while excretion of N-acetylglucosaminidase (E_NAG) reflected the extent of kidney tubular cell injury. In participants with an elevated excretion of E_β2M, the prevalence odds ratios (POR) for a reduced eGFR rose 6.4-fold, whereas the POR for albuminuria rose 4.3-fold, 4.1-fold, and 2.8-fold in those with a reduced eGFR, diabetes, and hypertension, respectively. Using covariance analysis, which adjusted for the interactions, 43% of the variation in E_alb among diabetics could be explained by female gender (η² = 0.176), E_NAG (η² = 0.162), hypertension (η² = 0.146), smoking (η² = 0.107), and body mass index (η² = 0.097), while the direct contribution of E_Cd to E_alb variability was minimal (η² = 0.005). Results from a mediating-effect analysis imply that Cd could contribute to albuminuria and a falling eGFR through inducing tubular cell injury, leading to reduced reabsorption of albumin and β₂M. Full article

Chronic kidney disease (CKD) is a progressive disease in which accurate estimation of glomerular filtration rate (GFR) is essential for staging and guiding therapy. Serum creatinine is widely used but influenced by non-renal factors, while cystatin C and β2-microglobulin (β2M) may provide complementary information related to filtration and tubular or inflammatory factors. This study compared the discriminatory performance of creatinine, cystatin C and β2M for separating CKD stage 3 from stage 4 within the 2021 CKD-EPI eGFR framework in 45 adults with CKD stages 3–4. CKD stage classification was defined using the 2021 CKD-EPI creatinine and creatinine–cystatin C equations (eGFRcr, eGFRcr–cys) with a threshold of 30 mL/min/1.73 m². Receiver operating characteristic (ROC) analysis evaluated each marker’s ability to distinguish moderate from severe CKD. Creatinine showed high diagnostic accuracy (AUC up to 0.98). Cystatin C achieved 100% specificity at the optimal cut-off for severe CKD and showed comparable diagnostic accuracy to creatinine under the eGFRcr–cys framework (AUC 0.978 vs. 0.957). β2M demonstrated AUCs up to 0.97, with sensitivity and specificity above 90%. These findings support a multi-marker evaluation within the 2021 CKD-EPI-based staging, rather than validation against measured GFR. Larger studies incorporating measured GFR and relevant clinical confounders are warranted. Full article

Objective: Prolongation of the QTc interval (QTc) is a known risk factor for ventricular arrhythmias and sudden cardiac death (SCD). Although ankylosing spondylitis (AS) is associated with systemic inflammation and metabolic alterations, data on the relationship between noninvasive fibrosis markers and QTc are limited. This study aimed to investigate the association between the FIB-4 index and QTc in patients with AS. Methods: A total of 82 consecutive patients with AS were enrolled in the study. Demographic characteristics, comorbidities, laboratory parameters, and medication use were also recorded. The FIB-4 index was calculated for each patient in the study. Surface 12-lead electrocardiograms were obtained, and the QTc was measured. Correlation analyses and multivariable linear regression models were used to identify the independent predictors of QTc. Results: The mean age of the study population was 42.4 ± 11.7 years, and 57.3% of the patients were men. Correlation analysis revealed significant associations between QTc and age, sex, the FIB-4 index, body mass index (BMI), hypertension, hyperlipidemia, and cardiovascular medication use, whereas hemoglobin and estimated glomerular filtration rate (eGFR) were negatively correlated with QTc. In the multivariable analysis, only sex (β = −0.306, p = 0.001) and the FIB-4 index (β = 0.379, p < 0.001) remained independently associated with QTc. Conclusion: Our findings demonstrate that the FIB-4 index is independently associated with the QTc in patients with AS. These results suggest that noninvasive fibrosis markers may provide additional insights into cardiovascular risk stratification in this population. Full article

Background: Kidney dysfunction is common in intracerebral hemorrhage (ICH), but it is unclear whether reduced estimated glomerular filtration rate (eGFR) on admission is an independent driver of short-term outcomes or a marker of overall vulnerability. Methods: In this single-center retrospective study, we analyzed the data of consecutive patients with spontaneous ICH. Results: Among 276 patients, 92 (33.3%) presented with eGFR < 60 mL/min/1.73 m² on admission. Only 17/92 (18.5%) had documented pre-existing chronic kidney disease (CKD). Acute kidney injury (AKI) occurred more often in patients with eGFR < 60 mL/min/1.73 m² than in those with eGFR ≥ 60 mL/min/1.73 m² (25.0% vs. 10.3%). In survival models, eGFR ≥ 60 mL/min/1.73 m², predicted higher 90-day survival in the baseline model (OR 3.031, p = 0.013) but was attenuated after adjustment for age and premorbid modified Rankin Scale (mRS) and was no longer independent after additional adjustment for laboratory markers. Across all models, the National Institutes of Health Stroke Scale (NIHSS) score, hematoma volume, and history of coronary artery disease remained robust predictors. Higher leukocyte count predicted lower survival, whereas higher hemoglobin predicted higher survival. Among survivors, favorable functional outcome was independently associated with lower NIHSS, younger age, lower premorbid mRS, and absence of documented CKD. Admission eGFR category was not independently associated. Conclusions: Reduced admission eGFR primarily reflects baseline frailty and systemic derangement rather than an independent determinant of short-term survival after full adjustment, whereas documented CKD is more informative for disability among survivors. AKI occurs more frequently in patients presenting with reduced eGFR, supporting close renal monitoring in acute ICH. Full article

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder marked by progressive kidney enlargement and cyst formation, often resulting in end-stage renal disease (ESRD). Oxidative stress (OxS) significantly contributes to renal damage in chronic kidney disease (CKD) and ADPKD. While the Mediterranean diet (Med-diet) is known for its antioxidative and anti-inflammatory effects, its impact on OxS in ADPKD remains unclear. This study aimed to assess the relationship between adherence to the Med-diet, OxS levels, and renal function in ADPKD patients. We enrolled 63 ADPKD patients aged 18–70 years with CKD stages G2–G4. Adherence to the Med-diet was evaluated using the PREDIMED questionnaire. OxS markers (NOX2-derived peptide [sNOX2-dp] and hydrogen peroxide [H₂O₂]) were measured via ELISA. Correlations between these markers, Med-diet adherence, serum creatinine, and estimated glomerular filtration rate (eGFR) were analyzed. Higher adherence to the Med-diet was associated with significantly lower OxS markers (sNOX2, p < 0.001; H₂O₂, p = 0.04). Reduced NOX2 and H₂O₂ levels correlated with lower creatinine and higher eGFR (NOX2, p < 0.001; H₂O₂, p < 0.001), suggesting an inverse relationship between OxS and renal function. In conclusion, adherence to the Mediterranean diet appears to be associated with lower levels of oxidative stress and may slow the progression of chronic kidney disease. These findings suggest that dietary interventions could mitigate disease progression by modulating OxS. Further studies are needed to confirm these results and explore the long-term effects of the Med-diet on disease progression. Full article

Chronic kidney disease (CKD) is associated with chronic inflammation and metabolic dysregulation. While endothelin-1 (ET-1) has been extensively studied, the role of endothelin-2 (ET-2) in CKD remains poorly understood. This cross-sectional study included 76 participants, 12 healthy controls and 64 CKD patients, stratified into three groups based on estimated glomerular filtration rate (eGFR): Group 1 (eGFR ≥ 90 mL/min/1.73 m²), Group 2 (eGFR 45–89 mL/min/1.73 m²), and Group 3 (eGFR 15–44 mL/min/1.73 m²). Serum concentrations of ET-1, ET-2, ET-3, uric acid (UA), and inflammatory markers (hsCRP and IL-6) were measured. ET-2 levels were significantly higher in the advanced CKD group (median 24.49 pg/mL) compared to controls (median 19.32 pg/mL; p = 0.030). No significant differences were observed for ET-1 or ET-3 across groups. ET-2 levels positively correlated with UA (rho = 0.243, p = 0.036), hsCRP (rho = 0.241, p = 0.039), and IL-6 (rho = 0.244, p = 0.038). These findings suggest that ET-2 may represent a potential biomarker reflecting metabolic and inflammatory dysregulation in CKD and highlight its possible relevance in disease severity assessment. Full article

Background and Hypothesis: Diabetic kidney disease (DKD) is one of the major risk factors for all-cause mortality and cardiovascular disease in patients with diabetes mellitus. Different phenotypes have been described. In view of their different pathophysiology, these subtypes may behave differently. Methods: In this retrospective study, patients with type 2 diabetes mellitus (T2DM) were followed up for a maximum of 10 years or until death, whichever came first. Subjects were categorized into four DKD phenotypes: no DKD (no albuminuria or decreased estimated glomerular filtration rate (eGFR)), albuminuria without decreased eGFR (DKD 1), decreased eGFR without albuminuria (DKD 2 or non-albuminuric DKD), and decreased eGFR with albuminuria (DKD 3). Data on laboratory results, hospitalization, and mortality were obtained through electronic patient records. Univariate analyses were performed and the variables that were significant were entered as covariates in multivariate logistic regression models to estimate the risks of death, hospitalization for CAD, HF, and CrVD, and CKD progression. Results: Among 778 patients, 53.3% had no DKD, 31.2% had DKD 1, 5.4% had DKD 2, and 10% had DKD 3. Patients with DKD 2 exhibited the highest odds of mortality compared to those with no DKD (odds ratio (OR) of 6.7 [95% CI 2.8–16.0], p < 0.001). Pairwise comparisons using the log-rank test showed a significant difference in mortality between DKD 1 and DKD 2 (p < 0.001) and DKD 1 and DKD 3 (p < 0.001). However, no statistically significant difference in mortality was found between DKD 2 and DKD 3. Additionally, the greater variability in HbA1c and higher neutrophil–lymphocyte ratio (NLR) independently predicted all-cause mortality as well as hospitalization for heart failure. Conclusions: This contemporary T2DM cohort demonstrated that the DKD phenotype, HbA1c variability, and elevated NLR are linked to increased mortality. These factors may improve existing risk stratification models by enabling better identification of high-risk DKD patients and guide more personalized management. Full article

The estimated glomerular filtration rate (eGFR) is a cornerstone of kidney function assessment. Widely used Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations based on serum creatinine (eGFR_cr), cystatin C (eGFR_cysC), or both (eGFR_cr-cysC) are influenced by non-glomerular filtration rate (GFR) factors, and their performance may vary across clinical contexts. We retrospectively analyzed 435 adult patients with simultaneous serum creatinine and cystatin C measurements. eGFR was calculated using CKD-EPI 2021 (creatinine), CKD-EPI 2012 (cystatin C), and CKD-EPI 2021 (combined) equations. Patients were classified into Kidney Disease: Improving Global Outcomes (KDIGO) GFR categories (G1–G5), and discrepancies between equations were identified. 44 patients (10.1%) showed discordant GFR categorization across all three equations and underwent detailed clinical assessment. 16 of the 44 discordant cases had clinically confirmed chronic kidney disease (CKD). The combined equation aligned with the clinical diagnosis in all CKD cases. eGFR_cr overestimated kidney function in 10/16 patients, while eGFR_cysC produced lower values in 8/16, consistent with early CKD but potentially influenced by inflammation or obesity. Reclassification occurred in 9/16 patients when switching from eGFR_cr to eGFR_cr-cysC, including four who shifted from G2 to G3a–G4. A significant difference was observed between eGFR_cr and eGFR_cr-cysC (p < 0.05). The combined CKD-EPI equation demonstrated the best clinical concordance, supporting its broader use when diagnostic accuracy is essential. Full article

Background: Diabetic kidney disease (DKD) is the most important cause of end-stage renal failure. The aim of this study is to investigate whether there is an association between supplementation of vitamin D and DKD or not. Methods: The study was designed prospectively and initiated with a total of 81 patients with a history of type 2 diabetes mellitus (DM) and diagnosed with stage 3 or 4 diabetic nephropathy (DN), who applied to Ankara University Faculty of Medicine between July 2011 and February 2013. It was completed with a total of 63 patients, 38 female (60.3%) and 25 male (39.7%), during the six-month follow-up period. The inclusion criteria were as follows: microalbumin ≥ 30 mg/day in 24 h urine, for which at least two measurements were obtained; age ≥ 18; HbA1c ≤ 8%; eGFR (estimated glomerular filtration rate) ≥ 30 mL/min; and, in addition, type 2 DM diagnosis. Patients with microalbumin levels of 30–299 mg/24 h were included in the microalbuminuria group, whereas patients with ≥300 mg were included in the macroalbuminuria group. An oral dose of 300,000 IU vitamin D3 replacement was given to patients with vitamin D deficiency and insufficiency. Results: In both groups, a significant increase in vitamin D levels at six months compared to baseline was observed, while a significant decrease in 24 h urine microalbumin and protein levels was observed at six months. Considering these results, vitamin D was considered to have a positive effect on 24 h urine microalbumin and protein levels. Conclusions: In both groups, a significant increase in vitamin D levels and a significant decrease in microalbumin and protein levels were detected at the sixth month via 24 h urine tests. Therefore, vitamin D replacement is thought to be beneficial for DKD treatment because of its antiproteinuric effect. Full article

Background: Both atrial cardiopathy and impaired renal function are independently associated with increased mortality, but their interrelationship and combined impact remain uncertain. Methods: We analyzed 6573 participants from NHANES-III (mean age 57 years; 50.5% women; 74.6% White) with available electrocardiograms (ECGs). Estimated glomerular filtration rate (eGFR) was calculated using the CKD-EPI equation. Atrial cardiopathy was defined by any of the following ECG markers: abnormal P-wave axis (<0° or >75°), deep terminal negativity in lead V1 (>100 µV), or prolonged P-wave duration in lead II (>120 ms). Participants with eGFR <15 mL/min/1.73 m² or major ECG abnormalities were excluded. Logistic regression assessed the association between impaired renal function (eGFR < 45 vs. ≥45 mL/min/1.73 m²) and atrial cardiopathy. Cox models evaluated independent and joint associations of impaired renal function and atrial cardiopathy with all-cause mortality. Results: About 47.9% (n = 3151) had atrial cardiopathy at baseline, of whom 161 (4.7%) had impaired renal function. Impaired renal function was associated with higher odds of atrial cardiopathy (OR 1.44; 95% CI 1.16–1.78). Over a median follow-up of 18.1 years, 3076 deaths occurred. Compared with participants without either condition, those with both had the highest mortality risk (HR 1.68; 95% CI 1.46–1.94), exceeding risks from atrial cardiopathy alone (HR 1.10; 95% CI 1.02–1.18) or impaired renal function alone (HR 1.42; 95% CI 1.18–1.70; p = 0.011 for interaction). Conclusions: Impaired renal function is associated with a greater prevalence of atrial cardiopathy. Their coexistence exerts a synergistic effect, substantially amplifying mortality risk beyond either condition alone. Full article

Background/Objectives: Associations between renal function, as measured by the estimated glomerular filtration rate (eGFR) or its decline (dGFR), and clinical parameters in patients with rheumatoid arthritis (RA) were evaluated using a retrospective case–control series dataset. Methods: Patients with RA who followed up for one or more consecutive years were recruited for the study. For calculating the eGFR, cystatin C (CysC) was adopted. The moment when CysC was measured was set as the baseline. The association between the eGFR and baseline clinical parameters, including disease activity in RA as measured by the simplified disease activity index (SDAI), was statistically evaluated. The association between the mean annual decline in the eGFR from the baseline and clinical parameters was also statistically assessed. Results: A total of 513 patients were enrolled; with a mean age of 70.9; a mean follow-up length of 52.5 months; a mean BMI of 22.9; a 68.7 eGFR; and a mean annual dGFR of 2.74. Significant parameters that correlated with the eGFR were age; rheumatoid factor titer; C-reactive protein; the presence of hypertension; chronic heart failure; chronic obstructive pulmonary disease; type 2 diabetes mellitus; methotrexate administration; and polypharmacy at baseline. An annual dGFR was correlated with the follow-up length, and the mean SDAI score multiplied by the yearly length of the follow-up was significantly correlated. Conclusions: Many factors confound the determination of the eGFR in RA patients. The disease activity score and length of time are the key factors for declining eGFRs. Full article

Background: Sarcopenia and sarcopenic obesity are increasingly recognized in kidney transplant recipients (KTRs), yet their molecular underpinnings remain poorly defined. We sought to synthesize current evidence on biomarker associations with muscle loss and function in the post renal transplant setting. Methods: A comprehensive search of PubMed/MEDLINE and Cochrane databases was conducted according to PRISMA guidelines. Studies evaluating biomarkers related to sarcopenia or sarcopenic obesity in adult and pediatric KTRs were included. Quality assessment was performed with the NHLBI tool. Results: Seven studies were included, encompassing 548 KTRs. Myostatin levels predicted sarcopenia in KTRs (cut-off: 390 pg/mL) and inversely correlated with Metabolic equivalent of Tasks (METs), handgrip strength (HGS), and graft performance. Although adiponectin was negatively correlated with body fat, its high-molecular-weight isoform was linked to lower muscle mass and long-term graft decline. Leptin was associated with sarcopenic obesity and lower estimated Glomerular Filtration Rate (eGFR). Insulin like Growth Factor-1 (IGF-1) independently predicted HGS but not muscle mass. Brain-derived neurotrophic factor (BDNF) levels predicted sarcopenia (cut off: 17.8 ng/mL) and reflected physical activity levels. Visfatin showed no association with sarcopenia but it was positively correlated with eGFR. Lastly, certain polymorphisms of Alpha-actinin-3 (ACTN3) were shown to genetically predispose to post-transplant sarcopenia. Conclusions: These emerging candidate biomarkers provide promising mechanistic insight into post-transplant muscle decline and may ultimately support more personalized risk assessment. Further validation is needed, and functional measures remain the most reliable clinical tools at present. Full article

Background and Objectives: IgA nephropathy represents the most prevalent form of primary glomerulonephritis around the world, with significant heterogeneity in management strategies and outcomes. We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of pharmacological interventions for IgA nephropathy. Materials and Methods: We searched multiple databases through June 2025, identifying randomized controlled trials and observational studies evaluating pharmacological treatments in biopsy-proven IgA nephropathy. Primary outcomes included proteinuria reduction and estimated glomerular filtration ration (eGFR) preservation. Secondary outcomes included hard kidney endpoints and safety parameters. Random-effects meta-analyses were performed with comprehensive risk–benefit assessments. Results: Twenty-five studies were included. B-cell/plasma-cell-targeted therapies showed significant proteinuria reduction (−34.0% [95% CI: −45.7, −22.3%]), complement pathway inhibitors demonstrated superior eGFR preservation (+5.8 mL/min/1.73 m²/year [95% CI: 2.4, 9.2]). Systemic corticosteroids showed observed hard outcome benefits (HR 0.37 [95% CI: 0.26, 0.52]) but highest adverse event risk (RR 3.28 [95% CI: 2.11, 5.09]). Novel agents showed projected favorable effects (B-cell: HR 0.38; complement: HR 0.42) pending validation. Conclusions: Novel targeted therapies, especially B-cell/plasma-cell-targeted agents and complement pathway inhibitors, show promising risk–benefit profiles. However, longer-term data and standardized eGFR slope reporting are needed to confirm these findings compared to other immunosuppressive agents. Full article

Background/Objectives: Kidney transplantation remains the most effective treatment for patients with end-stage kidney disease, increasing both survival and quality of life. There are concerns regarding the long-term outcomes of donors in developing countries, as kidney transplants are predominantly performed from living donors. This study was conducted to evaluate the long-term clinical outcomes of living kidney donors, with a particular focus on kidney and cardiovascular health. Methods: We retrospectively reviewed the records of 232 individuals who underwent donor nephrectomy between January 2011 and November 2022. Cardiovascular events, mortality, chronic kidney disease, hypertension, and newly onset diabetes were assessed. Estimated glomerular filtration rate (eGFR) values were employed to monitor kidney function over time. Results: Living kidney donors were monitored for a median of 6 years (IQR: 4–9 years). During the follow-up period, 18.9% of donors experienced a decline in eGFR to below 60 mL/min/1.73 m²; however, none progressed to end-stage kidney disease. Of the cohort, 20 (8.6%) had newly onset proteinuria and none had proteinuria before transplantation. Although there were no recorded deaths from cardiovascular causes, 4.3% of donors experienced major adverse cardiac events. 12.3% of donors had newly diagnosed hypertension following transplantation, and 20.2% of donors had hypertension overall. Lower baseline eGFR, treated as a continuous variable in the logistic regression model, was independently associated with a higher likelihood of post-donation eGFR < 60 mL/min/1.73 m² (OR: 0.91; 95% CI: 0.88–0.94; p < 0.001). Post donation proteinuria (OR: 6.61; 95% CI: 1.98–22.07, p: 0.002) was also identified as independent risk factors for decline in eGFR to below 60 mL/min/1.73 m². Diabetes mellitus was found to be a significant predictor of newly onset hypertension. Conclusions: A considerable percentage of the donors experienced gradual deterioration in kidney function, even though none of them developed kidney failure necessitating dialysis. The prevalence of obesity and chronic kidney disease was higher post-donation compared to the general population, indicating the need for structured long-term monitoring. Full article

Glomerular filtration rate (GFR) is a key indicator of renal function. Traditional methods for GFR measurement have limitations including invasiveness, low spatial resolution, and lengthy protocols. Positron emission tomography (PET) radiotracers have emerged as promising tools for non-invasive, accurate, and dynamic renal function assessment. Objectives: This systematic literature review evaluates the clinical utility, and current evidence surrounding PET radiotracers used for GFR measurement in humans, emphasizing advances over conventional renal imaging modalities. Methods: A systematic literature search was conducted in PubMed, Web of Science, and Scopus, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, from database inception to November 2024. The search identified studies evaluating PET-based measurement of glomerular filtration rate (GFR) and renal perfusion. Inclusion criteria encompassed human studies using PET radiotracers (e.g., ⁶⁸Ga, ¹⁸F) with comparisons to reference standards (estimated GFR or serum creatinine). Two authors independently screened titles/abstracts, extracted data, and assessed bias using Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2). Exclusions included animal studies, reviews, and non-English articles. Results: Eleven studies met inclusion criteria, with ⁶⁸Ga-EDTA showing the highest validation against reference standards such as ⁵¹Cr-EDTA plasma clearance, demonstrating strong correlation. PET imaging offered superior spatial–temporal resolution, enabling accurate split renal function assessment and quantitative analysis of both filtration and perfusion. ⁶⁸Ga-somatostatin analogues exhibited moderate correlations between renal SUV and estimated GFR, with post-PRRT uptake changes indicating early nephrotoxicity. Among novel tracers, ⁶⁸Ga-FAPI showed a strong inverse SUV–GFR relationship, reflecting renal fibrosis and suggesting potential as a chronic kidney disease (CKD) biomarker but requires further clinical validation. Limitations across studies include small sample sizes, retrospective designs, and variability in reference standards. Conclusions: PET radiotracers, particularly ⁶⁸Ga-EDTA, represent a significant advancement for non-invasive, quantitative GFR measurement with improved precision and renal anatomical detail compared to traditional methods. Future prospective, large-scale human studies with standardized protocols are needed to establish these PET tracers as routine clinical tools in nephrology. Integration of hybrid PET/MRI and novel tracer development may further enhance renal diagnostic capabilities. Full article