Uromodulin, released from tubular cells of the ascending limb into the blood, may be associated with kidney function. This work studies the relevance of plasma uromodulin as a biomarker for kidney function in an observational cohort of chronic kidney disease (CKD) patients and subjects without CKD (CKD stage 0). It should be further evaluated if uromodulin allows the identification of early CKD stages.Plasma uromodulin, serum creatinine, cystatin C, blood-urea-nitrogen (BUN) concentrations, and estimated glomerular filtration rate (eGFR CKD-EPIcrea-cystatin) were assessed in 426 individuals of whom 71 were CKD stage 0 and 355 had CKD. Besides descriptive statistics, univariate correlations between uromodulin and biomarkers/eGFR were calculated using Pearson-correlation coefficient. Multiple linear regression modeling was applied to establish the association between uromodulin and eGFR adjusted for demographic parameters and pharmacologic treatment. Receiver-operating-characteristic (ROC) analysis adjusted for demographic parameters was performed to test if uromodulin allows differentiation of subjects with CKD stage 0 and CKD stage I.Mean uromodulin plasma levels were 85.7 ± 60.5 ng/mL for all CKD stages combined. Uromodulin was correlated with all biomarkers/eGFR in univariate analysis (eGFR: r = 0.80, creatinine: r = −0.76, BUN: r = −0.72, and cystatin C: r = −0.79). Multiple linear regression modeling showed significant association between uromodulin and eGFR (coefficient estimate β = 0.696, 95% confidence interval [CI] 0.603–0.719, P < 0.001). In ROC analysis uromodulin was the only parameter that significantly improved a model containing demographic parameters to differentiate between CKD 0° and I° (area under the curve [AUC] 0.831, 95% CI 0.746–0.915, P = 0.008) compared to creatinine, cystatin C, BUN, and eGFR (AUC for creatinine: 0.722, P = 0.056, cystatin C: 0.668, P = 0.418, BUN: 0.653, P = 0.811, and eGFR: 0.634, P = 0.823).Plasma uromodulin serves as a robust biomarker for kidney function and uniquely allows the identification of early stages of CKD. As a marker of tubular secretion it might represent remaining nephron mass and therefore intrinsic “kidney function” rather than just glomerular filtration, the latter only being of limited value to represent kidney function as a whole. It therefore gives substantial information on the renal situation in addition to glomerular filtration and potentially solves the problem of creatinine-blind range of CKD, in which kidney impairment often remains undetected.

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Introduction Autosomal dominant tubulo-interstitial kidney disease due to UMOD mutations (ADTKD- UMOD ) is a rare condition associated with high variability in the age of end-stage kidney disease (ESKD). The minor allele of rs4293393, located in the promoter of the UMOD gene, is present in 19% of the population and downregulates uromodulin production by approximately 50% and might affect the age of ESKD. The goal of this study was to better understand the genetic and clinical characteristics of ADTKD- UMOD and to perform a Mendelian randomization study to determine if the minor allele of rs4293393 was associated with better kidney survival. Methods An international group of collaborators collected clinical and genetic data on 722 affected individuals from 249 families with 125 mutations, including 28 new mutations. The median age of ESKD was 47 years. Men were at a much higher risk of progression to ESKD (hazard ratio 1.78, P < 0.001). Results The allele frequency of the minor rs4293393 allele was only 11.6% versus the 19% expected ( P < 0.01), resulting in Hardy-Weinberg disequilibrium and precluding a Mendelian randomization experiment. An in vitro score reflecting the severity of the trafficking defect of uromodulin mutants was found to be a promising predictor of the age of ESKD. Conclusion We report the clinical characteristics associated with 125 UMOD mutations. Male gender and a new in vitro score predict age of ESKD.

Background: “T50,” shortened transformation time from primary to secondary calciprotein particles may reflect deranged mineral metabolism predisposing to vascular calcification and cardiovascular disease (CVD). The glycoprotein fetuin-A is a major T50 determinant. Methods: The Folic Acid For Vascular Outcome Prevention In Transplantation (FAVORIT) cohort is a completed, large, multiethnic controlled clinical trial cohort of chronic, stable kidney transplant recipients (KTRs). We conducted a longitudinal case-cohort analysis using a randomly selected subcohort of patients, and all individual cases who developed CVD. Serum T50 and fetuin-A were determined in this total of n = 685 FAVORIT trial participants at randomization. Results: During a median surveillance of 2.18-years, 311 incident or recurrent CVD events occurred. Shorter T50 (minutes) or reduced fetuin-A concentrations (g/L) were associated with CVD after adjustment for treatment assignment, systolic blood pressure, age, sex, race, preexisting CVD and diabetes, smoking, body mass index, total cholesterol/HDL cholesterol, kidney allograft vintage and type, calcineurin inhibitor, or lipid-lowering drug use, estimated glomerular filtration rate, and urinary albumin/creatinine: tertile 1 (lowest) to tertile 3 (highest) comparisons, T50, (hazard ratio [HR] 1.86; 95% CI 1.20–2.89); fetuin-A, (HR 2.25; 95% CI 1.38–3.69). Elevated high sensitivity c-reactive protein (hsCRP) was an effect modifier of both these associations. Conclusions: Shortened T50, as well as reduced fetuin-A levels, ostensible promoters of vascular calcification, remained associated with greater risk for CVD outcomes, after adjustment for major CVD risk factors, measures of kidney function and damage, and KTR clinical characteristics and demographics, in a large, multiethnic cohort of long-term KTRs. Increased hsCRP was an effect modifier of these CVD risk associations.

The clinical utility of portable ultrasound machines is limited. There will be clinical roles for distinct clinical questions such as detection of ascites or pleural effusion when used by experienced examiners. However, sensitivity in detecting multiple pathologies is not comparable to high-end ultrasound machines.

Aim: To evaluate the effect of empagliflozin on uric acid (UA) levels, antigout medication and gout episodes in the EMPA-REG OUTCOME trial (NCT01131676). Materials and methods:A total of 7020 patients with type 2 diabetes (T2D) were randomized to either empagliflozin (10 or 25 mg) or placebo. The effects of empagliflozin versus placebo on UA concentration were assessed using mixed linear models. A composite outcome of new prescription of antigout medication or gout episode was studied with Cox proportional hazards models.Results: Empagliflozin reduced serum UA levels versus placebo: week 52 adjusted mean treatment difference = À0.37 (95% confidence interval [CI] À0.42, À0.31) mg/dL; this was more pronounced in patients with baseline UA ≥ 7.0 mg/dL versus <7.0 mg/dL: week 52 adjusted mean treatment difference = À0.56 (95% CI À0.68, À0.43) and À0.30 (95% CI À0.37, À0.24) mg/dL, respectively. Among 6607 patients not taking antigout medications at baseline, 5.2% had a gout episode or initiated antigout treatment versus 3.6% in the placebo and empagliflozin groups, respectively: hazard ratio 0.67 (95% CI 0.53, 0.85; P = 0.001). Both components of the composite outcome contributed to the reduction with empagliflozin in the composite. Risk reduction was similar with both empagliflozin doses.Conclusions: Empagliflozin reduced UA levels and the composite of gout episodes or prescription of antigout medication. These clinically important findings expand the utility of empagliflozin as a potential antigout treatment in patients with T2D, beyond its well-established cardio-renal benefits.

Impaired cytomegalovirus (CMV)-specific cell-mediated immunity (CMV-CMI) is a major cause of CMV reactivation and associated complications in solid-organ transplantation. Reliably assessing CMV-CMI is desirable to individually adjust antiviral and immunosuppressive therapy. This study aimed to evaluate the suitability of T-Track CMV, a novel IFN-γ ELISpot assay based on the stimulation of peripheral blood mononuclear cells with pp65 and IE-I CMV proteins, to monitor CMV-CMI following kidney transplantation. A prospective longitudinal multicenter study was conducted in 86 intermediate-risk renal transplant recipients. CMV-CMI, CMV viral load, and clinical complications were monitored over 6 months post-transplantation. Ninety-five percent and 88-92% ELISpot assays were positive pre- and post-transplantation, respectively. CMV-specific response was reduced following immunosuppressive treatment and increased in patients with graft rejection, indicating the ability of the ELISpot assay to monitor patients' immunosuppressive state. Interestingly, median pp65-specific response was ninefold higher in patients with self-clearing viral load compared to antivirally treated patients prior to first viral load detection (P < 0.001), suggesting that reactivity to pp65 represents a potential immunocompetence marker. Altogether, T-Track CMV is a highly sensitive IFN-γ ELISpot assay, suitable for the immunomonitoring of CMV-seropositive renal transplant recipients, and with a potential use for the risk assessment of CMV-related clinical complications (ClinicalTrials.gov Identifier: NCT02083042).