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Background: There is an ongoing debate as to whether early diabetic nephropathy in Type 2 diabetes mellitus may be attributed to the glomerulus or to the proximal tubule. Urinary excretion of nephrin and vascular endothelial growth factor may increase even in the normoalbuminuria stage. In the course of diabetic nephropathy, the proximal tubule may be involved in the uptake of urinary nephrin and vascular endothelial growth factor., Materials and Methods: Two groups of consecutive Type 2 diabetes mellitus outpatients (38 normo-, 32 microalbuminuric) and 21 healthy subjects were enrolled in a cross-sectional study and evaluated concerning the relation of proximal tubule dysfunction with the podocyte biomarkers excretion, assessed by ELISA methods. The impact of advanced glycation end-products on this relation was also queried., Results: Urinary alpha1-microglobulin and kidney injury molecule-1 correlated with urinary albumin:creatinine ratio (R2 = 0.269; p < 0.001; R2 = 0.125; p < 0.001), nephrinuria (R2 = 0.529; p<0.001; R2 = 0.203; p < 0.001), urinary vascular endothelial growth factor (R2 = 0.709; p < 0.001; R2 = 0.360; p < 0.001), urinary advanced glycation end-products (R2 = 0.578; p < 0.001; R2 = 0.405; p < 0.001), serum cystatin C (R2 = 0.130; p < 0.001; R2 = 0.128; p<0.001), and glomerular filtration rate (R2 = 0.167; p < 0.001; R2 = 0.166; p < 0.001); nephrinuria and urinary vascular endothelial growth factor correlated with urinary albumin:creatinine ratio (R2 = 0.498; p < 0.001; R2 = 0.227; p<0.001), urinary advanced glycation end-products (R2 = 0.251; p < 0.001; R2 = 0.308; p < 0.001), serum cystatin C (R2 = 0.157; p < 0.001; R2 = 0.226; p < 0.001), and glomerular filtration rate (R2 = 0.087; p = 0.007; R2 = 0.218; p < 0.001)., Conclusions: In Type 2 diabetes mellitus there is an association of proximal tubule dysfunction with podocyte damage biomarkers, even in the normoalbuminuria stage. This observation suggests a potential role of the proximal tubule in urinary nephrin and urinary vascular endothelial growth factor processing in early diabetic nephropathy, a fact which could be related to advanced glycation end-products intervention. Podocyte damage and proximal tubule dysfunction biomarkers could be validated as a practical approach to the diagnosis of early diabetic nephropathy by further studies on larger cohorts.

Background: Over the years, it was noticed that patients with diabetes have reached an alarming number worldwide. Diabetes presents many complications, including diabetic kidney disease (DKD), which can be considered the leading cause of end-stage renal disease. Current biomarkers such as serum creatinine and albuminuria have limitations for early detection of DKD. Methods: In our study, we used UHPLC-QTOF-ESI+-MS techniques to quantify previously analyzed metabolites. Based on one-way ANOVA and Fisher's LSD, untargeted analysis allowed the discrimination of six metabolites between subgroups P1 versus P2 and P3: tryptophan, kynurenic acid, taurine, l-acetylcarnitine, glycine, and tiglylglycine. Results: Our results showed several metabolites that exhibited significant differences among the patient groups and can be considered putative biomarkers in early DKD, including glycine and kynurenic acid in serum (p < 0.001) and tryptophan and tiglylglycine (p < 0.001) in urine. Conclusions: Although we identified metabolites as potential biomarkers in the present study, additional studies are needed to validate these results. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) has emerged as one of the most progressive diseases with increased mortality and morbidity. Metabolomics offers new insights into CKD pathogenesis and the discovery of new biomarkers for the early diagnosis of CKD. The aim of this cross-sectional study was to assess metabolomic profiling of serum and urine samples obtained from CKD patients. Untargeted metabolomics followed by multivariate and univariate analysis of blood and urine samples from 88 patients with CKD, staged by estimated glomerular filtration rate (eGFR), and 20 healthy control subjects was performed using ultra-high-performance liquid chromatography coupled with electrospray ionization-quadrupole-time of flight-mass spectrometry. Serum levels of Oleoyl glycine, alpha-lipoic acid, Propylthiouracil, and L-cysteine correlated directly with eGFR. Negative correlations were observed between serum 5-Hydroxyindoleacetic acid, Phenylalanine, Pyridoxamine, Cysteinyl glycine, Propenoylcarnitine, Uridine, and All-trans retinoic acid levels and eGFR. In urine samples, the majority of molecules were increased in patients with advanced CKD as compared with early CKD patients and controls. Amino acids, antioxidants, uremic toxins, acylcarnitines, and tryptophane metabolites were found in all CKD stages. Their dual variations in serum and urine may explain their impact on both glomerular and tubular structures, even in the early stages of CKD. Patients with CKD display a specific metabolomic profile. Since this paper represents a pilot study, future research is needed to confirm our findings that metabolites can serve as indicators of early CKD. [ABSTRACT FROM AUTHOR]

Introduction: Acute kidney injury (AKI) increases the risk of death in acute ischemic stroke (AIS) patients. Intravenous thrombolytic therapy (iv. rt-PA) seems to be the most effective treatment for AIS patients. The effects of AKI on iv. rt-PA treated AIS cases is less studied. Our paper addresses this issue. Methods: 45 consecutive stroke patients treated with iv. rt-PA (median age = 64 years; 29 male) and 59 age and sex matched controls not eligible for iv. rt-PA have been enrolled in our study. Subjects were followed-up until hospital release or death (median follow up time = 12 days). Results: The prevalence of AKI did not differ between iv. rt-PA treated patients and controls (35.5% vs. 33.89%). In both groups, AKI was associated with increased in-hospital mortality: 50.0% vs. 3.4% p<0.0001 (in the rt-PA treated), and 45% vs. 30.7% (in controls). AKI iv. rt-PA treated patients had a significantly higher risk of in hospital mortality as compared to the no-AKI iv. rt-PA treated (HR = 15.2 (95%CI [1.87 to 124.24]; P = 0.011). In a Cox-multivariate model, the presence of AKI after iv. rt-PA remained a significant factor (HR = 8.354; p = 0.041) influencing the in-hospital mortality even after correction for other confounding factors. The independent predictors for AKI were: decreased eGFR baseline and elevated serum levels of uric acid at admission, (the model explained 60.2% of the AKI development). Conclusions: The risk of AKI was increased in AIS patients. Thrombolysis itself did not increase the risk of AKI. In the iv. rt-PA patients, as compared to non-AKI, those which developed AKI had a higher rate of in-hospital mortality. The baseline eGFR and the serum uric acid at admission were independent predictors for AKI development in the iv. rt-PA treated AIS patients. [ABSTRACT FROM AUTHOR]

Patients with end-stage renal disease (ESRD) have an increased risk of all-cause mortality. The prognostic value of the new cardiac biomarkers, cardiotrophin 1 (CT-1) and galectin 3 (GAL-3), has not yet been defined in hemodialysis (HD) patients. The aim of this study was to determine the use of these novel biomarkers for predicting mortality in HD patients. Plasma GAL-3 and CT-1 concentrations were determined (at baseline) in 88 HD patients followed for 22.2 ± 4.7 months. During the follow-up period, 21 (23.9%) deaths were recorded. According to Cox analysis, the cutoff point for GAL-3 as a predictor of mortality was 23.73 ng/mL, while the cutoff point for CT-1 as a predictor of mortality was 36 pg/mL. In univariate analysis, only GAL-3 >23.73 ng/mL was an independent predictor of mortality (hazard ratio 2.60; 95% confidence interval, 1.09-6.18). In a multivariable Cox proportional hazards model, GAL-3 levels above the cutoff value remained an independent predictor of all-cause mortality. Our data suggest that similar to the general population, GAL-3 is an independent predictor of mortality in HD patients. [ABSTRACT FROM AUTHOR]

Background and aims: In order to assess the role played by tubular epithelial cells (TEC) and interstitial vascular endothelial cells (VEC) in interstitial fibrogenesis in human glomerulonephritis, we studied the expression of markers of activated fibroblasts (α-smooth muscle actin (αSMA) and vimentin (Vim)) and of the transforming growth factor β (TGFβ), at the level of these cells. Methods: We studied retrospectively 41 renal biopsies from patients with primary and secondary glomerulonephritis [24 males, 17 females, mean age 45.5 ± 12.9 years]. Immunohistochemistry using monoclonal antibodies (SMA, Vim, TGFβ) was assessed using a semiquantitative score, that was correlated with biological and histological data (quantified using a scoring system in order to assess active-inflammatory and chronic-sclerotic/fibrotic lesions). Results: The presence of SMA and Vim as markers of myofibroblasts was found in TECs and VECs. TEC Vim expression correlated with interstitial Vim expression ( r = 0.38; p = 0.008), interstitial infiltrate ( r = 0.31; p = 0.027), interstitial fibrosis ( R = 0.25; p = 0.042), GFR ( r = −0.35; p = 0.016), SMA ( r = −0.42; p = 0.015), TGFβ ( r = 0.25; p = 0.046), and hemoglobin ( r = −0.55; p < 0.001). VEC Vim expression showed indirect correlations with interstitial infiltrate ( r = −0.32; p = 0.023) and interstitial fibrosis ( r = −0.34; p = 0.017). Conclusion: Our study reflects the complexity of the involvement of VEC and mainly of TEC in fibrosis. The expression of mesenchymal markers at the tubular cell level (especially Vim) correlates with histological interstitial changes, with the decrease of renal function and more strongly with anemia. [ABSTRACT FROM AUTHOR]

Introduction: The solitary kidney (SK) may present increased vulnerability to nephrotoxicity because of adaptive phenomena. Aims: Assessing the vulnerability of the SK with urinary tract infections (UTI) to gentamicin by means of urinary biomarkers ( N-acetyl-beta-D-glucosaminidase (NAG) and urinary alpha-1-microglobulin), as well as glomerular filtration rate (GFR). Methods: We studied 14 patients with SK with UTI (group A) (mean age 58.07 ± 13.61 years, mean duration of SK 13.55 ± 12.33 years) who were administered gentamicin for 7 days. Group B consisted by 17 patients with SK without any other associated renal pathology (average age 51.17 ± 9.39 years, average existence period of a single kidney 33.23 ± 21.73 years). We also included a third group (group C) represented by nine healthy individuals, with two kidneys. Results: Increased values of urinary NAG were found in group B as compared to group C and alpha-1 microglobulin in group A as compared to group B. During treatment with gentamicin, increased values of both NAG and alpha-1-microglobulin in group A were found on day 7 as compared to values before treatment (day 7 NAG = 18.99 ± 14.07 U/g creat versus day 0, NAG = 5.15 ± 6.54 U/g creat, p = 0.004; day 7 alpha-1-microglobulin = 20.88 ± 18.84 mg/g creat versus day 0, urinary alpha-1-microglobulin = 4.96 ± 6.57 mg/g creat, p = 0.003). No statistically significant alterations of GFR were noticed after 7 days of treatment. Conclusions: We found the nephrotoxic effects of gentamicin at tubular level, but not at glomerular level. The nephrotoxic potential of gentamicin in patients with a SK can be monitored by assessing urinary biomarkers during treatment of UTI. [ABSTRACT FROM AUTHOR]

Introduction: The solitary kidney (SK) is currently debated in the literature, as living kidney donation is extensively used and the diagnosis of congenital SK is frequent. Tubulointerstitial lesions associated with adaptive phenomena may occur early within the SK. Aims: Analysis of the significance of urinary biomarkers in the assessment of tubulointerstitial lesions of the SK. Methods: A cross-sectional study of 37 patients with SK included 18 patients-acquired SK (mean age 56.44 ± 12.20 years, interval from nephrectomy 10.94 ± 9.37 years), 19 patients-congenital SK (mean age 41.52 ± 10.54 years). Urinary NAG, urinary alpha-1-microglobulin, albuminuria, eGFR (CKD-EPI equation) were measured. Results: In acquired SK, NAG increased in 60.66%, urinary alpha 1-microglobulin in 16.66%, albuminuria in 55.55% of patients. Inverse correlation with eGFR presented NAG ( R2 = 0.537, p = 0.022), urinary alpha 1-microglobulin ( R2 = 0.702, p = 0.001), albuminuria ( R2 = 0.655, p = 0.003). In congenital SK, NAG increased in 52.63%, urinary alpha 1-microglobulin in 5.26%, albuminuria in 47.36% of patients. In this group, urinary biomarkers correlated inversely with eGFR: NAG ( R2 = 0.743, p < 0.001), urinary alpha 1-microglobulin ( R2 = 0.701, p = 0.001), albuminuria ( R2 = 0.821, p < 0.001). Significant correlations were found between the urinary biomarkers in both groups. Conclusions: Urinary biomarkers allow a non-invasive, sensitive, early assessment of the tubular lesions of the SK. Urinary biomarkers of PT injury parallel renal function decline, thus complementing the estimation of GFR. Monitoring of PT dysfunction is mandatory in patients with SK. [ABSTRACT FROM AUTHOR]

The solitary kidney (SK) undergoes adaptive phenomena of hyperfunction and hyperfiltration. These secondary adaptive phenomena can make it more vulnerable to potentially nephrotoxic therapies. Adverse reactions of the kidneys to ciprofloxacin are rare, but sometimes severe. Therefore, our study sought to assess the reactions to ciprofloxacin of patients with solitary kidney (SK) and urinary tract infection (UTI) by means of urinary biomarkers. We studied 19 patients with SK and urinary tract infection (UTI) who had been administered a 7-day treatment with intravenous ciprofloxacin. Urinary N -acetyl-beta- d -glucosaminidase, alpha 1-microglobulin, and estimated glomerular filtration rate (eGFR) of these patients were measured at the initiation and at the end of treatment. In 47.37% patients NAG diminished under ciprofloxacin treatment. This observation has the significance of favourable evolution of the tubulointerstitial lesions caused by UTI and lack of nephrotoxic effects; 52.63% cases presented an increase of urinary NAG, a fact that suggests a nephrotoxic effect of ciprofloxacin. The evolution of urinary alpha 1-microglobulin was similar to that one of urinary NAG. Only one of three cases with chronic kidney disease (CKD) stage 5 presented acute kidney injury, associated with increase in the tubular markers. In spite of the high variability of the urinary biomarkers, UTI evolved favourably in these cases; eGFR increased in 16 out of 19 patients, a fact which is indicative of a good outcome of renal function, even in patients with elevated levels of the tubular damage biomarkers. This observation supports the hypothesis that eGFR may be dissociated from the biomarkers which assess tubular injury. In SK patients the occurrence of AKI is not frequent, although the urinary biomarkers rise in some patients treated with ciprofloxacin. This is related not only to the nephrotoxic effect of the drug, but probably to the association of other factors (allergy, individual susceptibility). In SK patients, renal tubular biomarkers, especially NAG, allow monitoring of tubular injury and impose caution in prescribing ciprofloxacin treatment, mainly to patients at risk. Ciprofloxacin is relatively safe regarding its nephrotoxicity, while caution is required in vulnerable patients. [ABSTRACT FROM AUTHOR]