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Rationale & Objective: Glomerular disorders have a highly variable clinical course, and biomarkers that reflect the molecular mechanisms underlying their progression are needed. Based on our previous work identifying plasminogen as a direct cause of podocyte injury, we designed this study to test the association between urine plasmin(ogen) (ie, plasmin and its precursor plasminogen) and end-stage kidney disease (ESKD)., Study Design: Multicenter cohort study., Setting & Participants: 1,010 patients enrolled in the CureGN Cohort with biopsy-proven glomerular disease (focal segmental glomerulosclerosis, membranous nephropathy, and immunoglobulin A nephropathy)., Predictors: The main predictor was urine plasmin(ogen) at baseline. Levels were measured by an electrochemiluminescent immunoassay developed de novo. Traditional clinical and analytical characteristics were used for adjustment. The ratio of urine plasmin(ogen)/expected plasmin(ogen) was evaluated as a predictor in a separate model., Outcome: Progression to ESKD., Analytical Approach: Cox regression was used to examine the association between urinary plasmin(ogen) and time to ESKD. Urinary markers were log 2 transformed to approximate normal distribution and normalized to urinary creatinine (Log 2 uPlasminogen/cr, Log 2 urinary protein/cr [UPCR]). Expected plasmin(ogen) was calculated by multiple linear regression., Results: Adjusted Log 2 uPlasminogen/cr was significantly associated with ESKD (HR per doubling Log 2 uPlasminogen/cr 1.31 [95% CI, 1.22-1.40], P<0.001). Comparison of the predictive performance of the models including Log 2 uPlasminogen/cr, Log 2 UPCR, or both markers showed the plasmin(ogen) model superiority. The ratio of measured/expected urine plasmin(ogen) was independently associated with ESKD: HR, 0.41 (95% CI, 0.22-0.77) if ratio<0.8 and HR 2.42 (95% CI, 1.54-3.78) if ratio>1.1 (compared with ratio between 0.8 and 1.1)., Limitations: Single plasmin(ogen) determination does not allow for the study of changes over time. The use of a cohort of mostly white patients and the restriction to patients with 3 glomerular disorders limits the external validity of our analysis., Conclusions: Urinary plasmin(ogen) and the ratio of measured/expected plasmin(ogen) are independently associated with ESKD in a cohort of patients with glomerular disease. Taken together with our previous experimental findings, urinary plasmin(ogen) could be a useful biomarker in prognostic decision making and a target for the development of novel therapies in patients with proteinuria and glomerular disease., Plain-Language Summary: Glomerular diseases are an important cause of morbidity and mortality in patients of all ages. Knowing the individual risk of progression to dialysis or transplantation would help to plan the follow-up and treatment of these patients. Our work studies the usefulness of urinary plasminogen as a marker of progression in this context, since previous studies indicate that plasminogen may be involved in the mechanisms responsible for the progression of these disorders. Our work in a sample of 1,010 patients with glomerular disease demonstrates that urinary plasminogen (as well as the ratio of measured to expected plasminogen) is associated with the risk of progression to end-stage kidney disease. Urine plasminogen exhibited good performance and, if further validated, could enable risk stratification for timely interventions in patients with proteinuria and glomerular disease., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective To assess the efficacy and safety of three treatment modalities (rituximab targeted B-cell therapy, calcium-phosphate inhibitor in conjunction with low-dose corticosteroids, and full-dose corticosteroids combined with cyclophosphamide) for patients at intermediate or high risk of idiopathic membranous nephropathy (IMN) and to analyze the factors impacting the remission rates of IMN. Methods A retrospective cohort study was conducted to analyze patients diagnosed with IMN in our nephrology department via renal biopsy, identifying a total of 148 patients at intermediate or high risk. These patients were categorized into three treatment groups: a RTX group with 60 patients receiving rituximab, a CNI group with 42 patients receiving calcineurin inhibitors, and a CTX group with 46 patients received cyclophosphamide. Baseline measurements of 24-hour urine protein, serum albumin, blood creatinine, uric acid, estimated glomerular filtration rate (eGFR), and serum anti-phospholipase A2 receptor antibody levels were recorded at the onset of the follow-up. Subsequently, changes in 24-hour urine protein, eGFR, remission rates, and occurrence of adverse events among the three patient groups were compared at 6, 12, and 18 months post-treatment. Moreover, COX regression analysis was employed to ascertain factors influencing the remission rate of IMN. Results At the outset of the follow-up period, no significant difference existed in baseline characteristics such as gender, age, 24-hour urine protein quantification, serum albumin, serum creatinine, uric acid, eGFR, serum anti-PLA2R antibody levels, body mass index (BMI), and systolic blood pressure among the patients, indicating the comparability of three groups. After 6 months, there were no notable changes in 24-hour urine protein quantification and eGFR among the three groups; however, remission rates in the RTX and CTX groups were lower than those in the CNI group. By the 12-month mark, 24-hour urine protein quantification in the RTX group significantly decreased compared to the CTX group, with overall remission rates showing no significant differences among the three groups. By the 18-month milestone, 24-hour urine protein quantification in the RTX group remained notably lower than that in the CTX group, with significantly higher eGFR levels. Additionally, the CTX group exhibited lower 24-hour urine protein quantification compared to the CNI group, with both RTX and CTX groups displaying higher remission rates than the CNI group. Predominant adverse reactions in the RTX group included infusion reactions and infections, whereas the CNI group were associated with metabolic syndrome and elevated serum creatinine, and the CTX group primarily experienced hepatic dysfunction. Multifactorial COX regression analysis revealed an association between baseline anti-PLA2R antibodies and remission rates of IMN (HR=1.162, 95% CI 1.078-1.249). Conclusion RTX therapy for IMN exhibits a gradual onset of action, boasting a superior disease remission rate at 18 months in comparison to CNI. It demonstrates a similarity to CTX in this aspect and offers prolonged maintenance of remission. Conversely, CNI demonstrates a rapid onset of action but poses a risk of exacerbating renal impairment in patients. Notably, elevated levels of serum anti-PLA2R antibodies emerge as an independent risk factor influencing remission in IMN.

Introduction: Disease subtyping and monitoring are essential for the management of nephrotic syndrome (NS). Although various biomarkers for NS have been reported, their clinical efficacy has not been comprehensively validated in adult Japanese patients., Methods: The Japanese Biomarkers in Nephrotic Syndrome (J-MARINE) study is a nationwide, multicenter, and prospective cohort study in Japan, enrolling adult (≥18 years) patients with minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MN), membranoproliferative glomerulonephritis (MPGN), C3 glomerulopathy (C3G), and lupus nephritis (LN). Baseline clinical information and plasma and urine samples will be collected at the time of immunosuppressive therapy initiation or biopsy. Follow-up data and plasma and urine samples will be collected longitudinally based on the designated protocols. Candidate biomarkers will be measured: CD80, cytotoxic T-lymphocyte antigen 4, and soluble urokinase plasminogen activator receptor for MCD and FSGS; anti-phospholipase A2 receptor and thrombospondin type-1 domain-containing protein 7A antibodies for MN; fragment Ba, C3a, factor I, and properdin for MPGN/C3G; and CD11b, CD16b, and CD163 for LN. Outcomes include complete and partial remission, relapse of proteinuria, a 30% reduction in estimated glomerular filtration rate (eGFR), eGFR decline, and initiation of renal replacement therapy. The diagnostic accuracy and predictive ability for clinical outcomes will be assessed for each biomarker., Results: From April 2019 to April 2023, 365 patients were enrolled: 145, 21, 138, 10, and 51 cases of MCD, FSGS, MN, MPGN/C3G, and LN, respectively., Conclusion: This study will provide valuable insights into biomarkers for NS and serve as a biorepository for future studies., (© 2024. The Author(s), under exclusive licence to Japanese Society of Nephrology.)

Background: Idiopathic membranous nephropathy (IMN) is a leading cause of end-stage renal disease (ESRD). The purpose of this study was to evaluate whether urinary albumin-to-creatinine ratio (UACR) diurnal variation rate calculated by spot urinary protein test predicts 1-year nephrotic outcomes as a biomarker of proteinuria severity in patients with IMN., Methods: Patients' baseline demographics, blood and urinary biomarkers, and clinical and pathological characteristics were collected retrospectively. Urine samples were collected at 7:00 (before breakfast) and 19:00 (after dinner) to calculate the UACR diurnal variation rate. A prediction model for no remission (NR) was developed statistically based on differences between prognosis groups. Receiver operating characteristic curve (ROC) analysis was performed to evaluate prediction abilities and determine optimal cut-off points of the model and UACR diurnal variation rate alone., Results: The formula for calculating the probability of NR was exp(L)/(1 + exp(L)), where the linear predictor L =  - 22.038 + 0.134 × Age (years) + 0.457 × 24-h urinary protein + 0.511 × blood urea nitrogen (BUN) + 0.014 × serum uric acid (SUA) + 2.411 if glomerular sclerosis + 0.816 × fasting blood glucose (FBG)-0.039 × UACR diurnal variation rate (%). Optimal cut-off points for NR prediction by the final model and UACR diurnal variation rate alone were 0.331 and 58.5%, respectively. Sensitivity and specificity were 0.889 and 0.859 for the final model, and 0.926 and 0.676 for UACR diurnal variation rate alone., Conclusion: UACR diurnal variation using spot urinary protein is a simpler way to predict nephrotic outcomes and is a highly sensitive screening tool for identifying patients who should undergo further comprehensive risk assessment., (© 2024. The Author(s).)

Background: Hematuria is frequently present in podocytopathies, but its significance and prognostic value is not well described in these proteinuric kidney diseases. This study describes the prevalence and association between hematuria and kidney-related outcomes in these disorders., Methods: Hematuria was assessed at the initial urinalysis in participants with the following podocytopathies-membranous nephropathy, minimal change disease, and FSGS-in the Nephrotic Syndrome Study Network and Cure Glomerulonephropathy cohorts with >24 months of follow-up. Multivariable Cox proportional hazards models were fit for time to composite outcome (kidney failure or 40% decline in eGFR and eGFR <60 ml/min per 1.73 m 2 ) and proteinuria remission (urine protein-to-creatinine ratio [UPCR] <0.3 mg/mg)., Results: Among the 1516 adults and children in the study, 528 participants (35%) had FSGS, 499 (33%) had minimal change disease, and 489 (32%) had membranous nephropathy. Median (interquartile range) time from biopsy until the initial study urinalysis was 260 (49-750) days, and 498 participants (33%) were positive for hematuria. Participants with hematuria compared with those without were older (37 [16-55] versus 33 [12-55] years), more likely to have an underlying diagnosis of membranous nephropathy (44% versus 27%), had shorter time since biopsy (139 [27-477] versus 325 [89-878] days), and had higher UPCR (3.8 [1.4-8.0] versus 0.9 [0.1-3.1] g/g). After adjusting for diagnosis, age, sex, UPCR, eGFR, time since biopsy, and study cohort, hematuria was associated with a higher risk of reaching the composite outcome (hazard ratio, 1.31; 95% confidence interval, 1.04 to 1.65; P value, 0.02) and lower rate of reaching proteinuria remission (hazard ratio, 0.80; 95% confidence interval, 0.65 to 0.98; P value, 0.03)., Conclusions: Hematuria is prevalent among participants with the three podocytopathies and is significantly and independently associated with worse kidney-related outcomes, including both progressive loss of kidney function and remission of proteinuria., (Copyright © 2023 by the American Society of Nephrology.)

This study aims to analyze the characteristics of idiopathic membranous nephropathy (iMN) with nondiabetic urine glucose during the follow-up. We retrospectively analyzed the data of 1313 patients who were diagnosed iMN. The prevalence of nondiabetic urine glucose during follow-up was 10.89%. There were significant differences between the patients with nondiabetic urine glucose and those without urine glucose in gender, hypertension ratio, proteinuria, N-acetyl-β-glucosaminidase, retinol binding protein, serum albumin, serum creatinine (Scr), cholesterol, triglyceride and positive anti-phospholipase A2 receptor antibody ratio, glomerular sclerosis ratio, acute and chronic tubular injury lesion at baseline. To exclude the influence of the baseline proteinuria and Scr, case control sampling of urine glucose negative patients was applied according to gender, baseline proteinuria and Scr. The proteinuria nonremission (NR) ratio was 45.83 versus 12.50% of the urine glucose positive group and case control group. Partial remission (PR) ratio of the two groups was 36.46 versus 23.96% and complete remission (CR) ratio was 19.79% versus 63.54%, respectively. Patients with urine glucose had higher risk of 50% estimated glomerular filtration rate (eGFR) reduction. Cox regression showed that urine glucose and baseline Scr were risk factors of 50% reduction of eGFR. Urine glucose remission ratio of the patients with proteinuria NR, PR, and CR was 13.33, 56.25, and 94.73% ( p  < 0.005). Patients who got urine glucose remission also had better renal survival. In conclusion, non-diabetic urine glucose was closely related to proteinuria. It could be applied as a tubular injury marker to predict renal function.

Anti-phospholipase A2 receptor autoantibody (PLA2R-Ab) plays a critical role in the pathogenesis of primary membranous nephropathy (PMN), an autoimmune kidney disease characterized by immune deposits in the glomerular subepithelial spaces and proteinuria. However, the mechanism of how PLA2R-Abs interact with the conformational epitope(s) of PLA2R has remained elusive. PLA2R is a single transmembrane helix receptor containing ten extracellular domains that begin with a CysR domain followed by a FnII and eight CTLD domains. Here, we examined the interactions of PLA2R-Ab with the full PLA2R protein, N-terminal domain truncations, and C-terminal domain deletions under either denaturing or physiological conditions. Our data demonstrate that the PLA2R-Abs against the dominant epitope (the N-terminal CysR-CTLD1 triple domain) possess weak cross-reactivities to the C-terminal domains beyond CTLD1. Moreover, both the CysR and CTLD1 domains are required to form a conformational epitope for PLA2R-Ab interaction, with FnII serving as a linker domain. Upon close examination, we also observed that patients with newly diagnosed PMN carry two populations of PLA2R-Abs in sera that react to the denatured CysR-CTLD3 (the PLA2R-Ab 1 ) and denatured CysR-CTLD1 (the PLA2R-Ab 2 ) domain complexes on Western blots, respectively. Furthermore, the PLA2R-Ab 1 appeared at an earlier time point than PLA2R-Ab 2 in patients, whereas the increased levels of PLA2R-Ab 2 coincided with the worsening of proteinuria. In summary, our data support that an integrated folding of the three PLA2R N-terminal domains, CysR, FnII, and CTLD1, is a prerequisite to forming the PLA2R conformational epitope and that the dominant epitope-reactive PLA2R-Ab 2 plays a critical role in PMN clinical progression., Competing Interests: Conflict of interest H. T. holds a patent to use the findings for developing diagnostic tests to monitor PMN clinical progress and prognosis, predict patient response to treatment, and developing new therapies for patient treatment. R. Z. is a student intern at ImmunoWork., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Aim: Idiopathic membranous nephropathy (IMN) has a varied clinical course that requires accurate prediction as a prerequisite for treatment administration. Currently, its prognosis relies on proteinuria, a clinical parameter whose onset lags behind kidney injury. Increased urinary excretion of matrix metalloproteinase-9 (MMP-9) and nephrin has been reported in a number of IMN-like glomerular diseases in which they reflected disease severity. However, little or nothing is known of the importance of these biomarkers in IMN, a major cause of adult nephrotic syndrome. To highlight their potential, we measured both biomarkers and assessed their relationships with key parameters of renal function in IMN., Methods: We quantified urinary MMP-9 and nephrin in 107 biopsy-proven IMN patients and 70 healthy subjects by enzyme-linked immunosorbent assay (ELISA). We then compared biomarker levels between patients and healthy subjects and among patients with different clinical features. We also determined the relationship of each biomarker with proteinuria and the estimated glomerular filtration rate (eGFR)., Results: Urinary MMP-9 and nephrin were significantly higher in IMN compared to healthy controls. Unlike nephrin, MMP-9 correlated significantly with proteinuria and was significantly higher among patients with nephrotic range proteinuria. Both biomarkers were correlated with eGFR, but only MMP-9 was significantly higher in patients with eGFR less than 90 ml/min/1.73 m 2 ., Conclusion: Our findings suggest that urinary MMP-9 holds a greater potential than urinary nephrin in monitoring the severity of IMN., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Akankwasa Gilbert et al.)

Background: Patients with both diabetes mellitus (DM) and kidney disease could have diabetic nephropathy (DN) or non-diabetic renal disease (NDRD). IgA nephropathy (IgAN) and membranous nephropathy (MN) are the major types of NDRD. No ideal noninvasive diagnostic model exists for differentiating them. Our study sought to construct diagnostic models for these diseases and to identify noninvasive biomarkers that can reflect the severity and prognosis of DN., Methods: The diagnostic models were constructed using logistic regression analysis and were validated in an external cohort by receiver operating characteristic curve analysis method. The associations between these microRNAs and disease severity and prognosis were explored using Pearson correlation analysis, Cox regression, Kaplan-Meier survival curves, and log-rank tests., Results: Our diagnostic models showed that miR-95-3p, miR-185-5p, miR-1246, and miR-631 could serve as simple and noninvasive tools to distinguish patients with DM, DN, DM with IgAN, and DM with MN. The areas under the curve of the diagnostic models for the four diseases were 0.995, 0.863, 0.859, and 0.792, respectively. The miR-95-3p level was positively correlated with the estimated glomerular filtration rate (p < 0.001) but was negatively correlated with serum creatinine (p < 0.01), classes of glomerular lesions (p < 0.05), and scores of interstitial and vascular lesions (p < 0.05). However, the miR-631 level was positively correlated with proteinuria (p < 0.001). A low miR-95-3p level and a high miR-631 level increased the risk of progression to end-stage renal disease (p = 0.002, p = 0.011)., Conclusions: These four microRNAs could be noninvasive tools for distinguishing patients with DN and NDRD. The levels of miR-95-3p and miR-631 could reflect the severity and prognosis of DN.

Background: Multicentric Castleman's disease is a life-threatening disorder involving a systemic inflammatory response and multiple organ failure caused by the overproduction of interleukin-6. Although renal complications of Castleman's disease include AA amyloidosis, thrombotic microangiopathy, and membranoproliferative glomerulonephritis, membranous nephropathy is relatively rare. We experienced a case of secondary membranous nephropathy associated with Castleman's disease., Case Presentation: The patient was a 43-year-old Japanese man who had shown a high zinc sulfate value in turbidity test, polyclonal hypergammaglobulinemia, anemia, and proteinuria. A physical examination revealed diffuse lymphadenopathy, an enlarged spleen and papulae of the body trunk. A skin biopsy of a papule on the patient's back showed plasma cells in the perivascular area and he was diagnosed with multicentric Castleman's disease, plasma cell variant. Kidney biopsy showed the appearance of bubbling in the glomerular basement membranes in Periodic acid methenamine silver stain and electron microscopy revealed electron dense deposits within and outside the glomerular basement membranes. Since immunofluorescence study showed predominant granular deposition of IgG1 and IgG2, he was diagnosed with secondary membranous nephropathy associated with Castleman's disease. He was initially treated with prednisolone alone, however his biochemical abnormalities did not improve. After intravenous tocilizumab (700 mg every 2 weeks) was started, his C-reactive protein elevation, anemia, and polyclonal gammopathy improved. Furthermore, his urinary protein level declined from 1.58 g/gCr to 0.13 g/gCr. The prednisolone dose was gradually tapered, then discontinued. He has been stable without a recurrence of proteinuria for more than 6 months., Conclusions: Tocilizumab might be a treatment option for secondary membranous nephropathy associated with Castleman's disease.

Idiopathic membranous nephropathy (iMN) is considered an immune-mediated disease where circulating autoantibodies against podocyte targets (mainly the PLA 2 R) cause the deposition of in-situ subepithelial immune-complexes. The consequent podocyte damage may cause cell detachment in urine (Podocyturia-PdoU). PdoU has been assessed in different kidney diseases, but limited data are available in iMN. In this study all patients with a diagnosis of iMN between 15/12/1999-16/07/2014 were tested for PLA 2 R antibodies (Ab anti-PLA 2 R, ELISA kit) and PdoU by flow cytometry with anti-podocalyxin antibody. A semi-quantitative PdoU score was defined according to the percentage of podocalyxin positive cells normalized to the total volume of sample and set relative to the urine creatinine measured in the supernatant. PdoU was positive in 17/27 patients (63%; 1+ score in 6/27-22.2%, 2+ in 4/27-14.8%, 3+ in 2/27-7.4%, 4+ in 5/27-18.5%). Only 2/7 patients with complete remission showed a positive PdoU (1+) while all six patients without remission have significant PdoU. PdoU+ was statistically correlated with the absence of remission and Ab anti-PLA 2 R + (p < 0.05) but PdoU, analysed as a continuous variable, showed a non-linear correlation with proteinuria or PLA 2 R antibody levels also in the cohort of patients with two available PdoU tests. In conclusion, PdoU could be detected in iMN and seems to be associated with commonly considered markers of disease activity (proteinuria and Ab anti-PLA 2 R) with a non-linear correlation. Despite data should be confirmed in large and prospective cohorts, according to the podocyte depletion hypothesis PdoU may represent an early marker of immunological activation with potential prognostic utility.

Background: We aimed to evaluate cyclophosphamide efficacy in the treatment of idiopathic membranous nephropathy (IMN) and explore the efficacy of phospholipase-A2 receptor antibody (PLA2R-Ab), 24 hours proteinuria, and serum albumin in predicting 6- and 12-month treatment effects., Methods: A retrospective analysis was performed on 135 patients with IMN who followed up after treatment. The observation points were before, and after 3, 6, and 12 months of treatment. We collected clinical indicator data at each observation point and measured PLA2R-Ab levels before and after 3-month treatment., Results: The remission rates at 3, 6, and 12 months of cyclophosphamide therapy for patients with IMN were 41.4, 74.8, and 76.1%, respectively. Patients in whom PLA2R-Ab turned negative within 3 months had high remission rates at 3, 6, and 12 months after treatment (P < .05). PLA2R-Ab change at 3 months had a strong correlation with 24 hours proteinuria change at 6 months. The change in albumin concentration before and after 3-month treatment was an independent variable related to remission rate at 6 months, and 24 hours proteinuria change before and after 6-month treatment was an independent variable related to remission rate at 12 months after treatment., Conclusion: Cyclophosphamide showed good efficacy at 3, 6, and 12 months for patients with IMN. Serum albumin change and PLA2R-Ab change at 3 months can be used as indicators to predict remission at 6 months, respectively. Moreover, 24 hours proteinuria change at 6 months can predict remission at 12 months., (© 2020 The Authors. Journal of Clinical Laboratory Analysis Published by Wiley Periodicals LLC.)

Differentiating primary and secondary membranous glomerulonephritis (MGN) using biomarkers for MGN is essential in patients' diagnosis, treatment and follow-up. Although biopsy has been the primary tool in making the diagnosis, not all patients can withstand it due to its invasive nature, and it cannot be used to monitor treatment. Hence, there is the need for less invasive or even non-invasive biomarkers for effective diagnosis, treatment monitoring and prognostication. This study aimed at providing an alternative way of differentiating primary and secondary MGN using enzyme-linked immunosorbent assay (ELISA) technique for serum and urine biomarkers (M-type phospholipase A2 receptor (PLA 2 R) and thrombospondin type-1 domain-containing 7A (THSD7A)) for prompt diagnosis, treatment and prognosis. A total of 125 subjects, including 81 primary and 44 secondary MGN subjects, were diagnosed from January 2012 to October 2019 at Hospital Serdang and Hospital Kuala Lumpur from which 69 subjects consisting of 45 primary and 24 secondary MGN subjects participated in the study. Of these, 13 primary MGN subjects were positive for both serum and urine anti-PLA 2 R antibodies (Ab) whereas only one secondary MGN subject associated with hepatitis B virus was positive for both serum and urine anti-PLA 2 R Ab. At the same time, anti-THSD7A Ab was found positive in four primary MGN subjects and two secondary MGN subjects with malignancy., Competing Interests: No conflict of interest. The funders had no role in the design of the study; in the collection, analyses or interpretation of data, in the writing of the manuscript or in the decision to publish the results.

Objectives: This study aimed to investigate the unique prognostic, clinical, and renal histopathological characteristics of patients with idiopathic membranous nephropathy (IMN) with different levels of proteinuria., Methods: This retrospective observational study included 190 IMN patients with low levels of proteinuria (low group), 193 IMN patients with medium levels of proteinuria (medium group), and 123 IMN patients with high levels of proteinuria (high group) treated between September 2006 and November 2015. Prognostic and baseline clinical and histopathological data were compared among the three groups. Poor prognostic events included the occurrence of a persistent 50% reduction in estimated glomerular filtration rate (eGFR), end-stage renal disease, or all-cause mortality., Results: The severity of clinical symptoms and laboratory indices, such as blood pressure; extent of edema and hematuria; levels of fibrinogen, immunoglobulin (Ig)-G, complement (C)-4, total protein, albumin (ALB), and serum creatinine (SCr); and eGFR increased with increasing proteinuria (all p< .001). Based on renal histopathology, the extent of segmental sclerosis and balloon adhesion and renal interstitial lesion stage also increased in severity with increasing proteinuria (all p< .001). The Kaplan-Meier analysis showed that compared with patients with low and medium levels of proteinuria, patients with high levels of proteinuria had significantly lower cumulative poor event-free renal survival rates (p= .0039)., Conclusions: Baseline proteinuria level is indicative of prognosis in IMN patients; the greater the extent of proteinuria is, the worse the prognosis.

Background: This investigation was managed to explore whether miR-193a in combination with two podocytes, namely, Wilms tumor type 1 (WT1) and podocalyxin (PODXL), were feasible in estimating onset and prognosis of idiopathic membranous nephropathy (IMN). Methods: We recruited a total of 189 healthy controls and 364 IMN patients, whose urine samples were prepared to measure the expression of miR-193a and PODXL. Meanwhile, renal tissues collected from above-mentioned IMN patients ( n  = 364) and renal cell carcinoma patients ( n  = 189) were arranged to determine the expression of WT1. Ultimately, receiver operating characteristic curves were constructed to appraise the performance of miR-193a, WT1, and PODXL in predicting renal survival of IMN patients. Results: The IMN patients were measured with up-regulated miR-193a expression and down-regulated WT1/PODXL expression, when compared with healthy controls ( p  < 0.05). Moreover, highly expressed miR-193a, lowly expressed WT1/PODXL, elevated amounts of proteinuria (>3.79 g/24 h)/serum creatinine (>174.63 μmol/L), and declined GFR (≤68.13 mL/min/1.73 m 2 ) were implicated as prominent biomarkers for the poor renal survival of IMN patients (all p  < 0.05). Notably, miR-193a combined with PODXL and WT1 generated optimal effects in differentiating IMN patients from healthy controls (AUC = 0.994) and also in anticipating the renal survival state of IMN patients (AUC = 0.824), when compared with strategies that merely employed ≤2 of the biomarkers. Conclusion: The combination of miR-193a, WT1, and PODXL might serve as a favorable strategy for expecting IMN prognosis.

Background: Complement activation plays a substantial role in the pathogenesis of primary membranous nephropathy (pMN). C5b-9, C3c, MBL, and factor B have been documented in the subepithelial immune deposits. However, the changing of complement activation products in circulation and urine is not clear., Methods: We measured the circulating and urinary levels of C1q, MBL, C4d, Bb, properdin, C3a, C5a, and sC5b-9, in 134 patients with biopsy-proven pMN, by enzyme-linked immunosorbent assay. All the plasma values were corrected by eGFR and all the urinary values were corrected by urinary creatinine and urinary protein excretion. Anti-PLA2R antibodies were measured in all patients., Results: The plasma complement activation products were elevated both in the patients with and without anti-PLA2R antibodies. C3a levels were remarkably increased in the circulation and urine, much higher than the elevated levels of C5a. C5b-9 was in normal range in plasma, but significantly higher in urine. The urinary C5a had a positive correlation with anti-PLA2R antibody levels and urinary protein. The plasma level of C4d was elevated, but C1q and MBL were comparable to healthy controls. Positive correlations were observed between plasma C4d/MBL and urinary protein, only in the patients with positive anti-PLA2R antibodies but not in those without. The plasma level of Bb was elevated and had positive correlation with urinary protein only in the patients without anti-PLA2R antibodies., Conclusion: Complement activation products were remarkable increased in pMN and may serve as sensitive biomarkers of disease activity. The complement may be activated through lectin pathway with the existence of anti-PLA2R antibodies, while through alternative pathway in the absence of antibody.

Background: Proteinuria is known to be associated with both kidney function deterioration and cardiovascular diseases. While proteinuria estimation from 24-h urine samples has traditionally been considered as the standard method for assessment of the degree of urinary protein excretion, sample collection is associated with several technical problems such as inaccurate collection and the potential spread of drug-resistant pathogens. Therefore, the spot urine protein/creatinine ratio (PCR) assessment is currently recommended as an alternative. While the utility of PCR has been validated, studies on the association between spot urine PCR and 24-h proteinuria (24HP) in patients with chronic glomerular nephritis (CGN) and nephrotic syndrome (NS) are limited. This study aimed to evaluate whether an estimated result from a spot urine PCR could sufficiently approximate the daily urine protein excretion amount from a 24-h urine sample in patients with immunoglobulin A nephropathy (IgAN), minimal change disease (MCD), and membranous nephropathy- nephrotic syndrome (MN-NS)., Methods: The study participants included 161 patients with IgAN, MCD, or MGN-NS at the Jikei University Kashiwa Hospital and Kanagawa Prefecture Shiomidai Hospital. The correlation between spot urine PCR and a 24-h urine protein was investigated using linear regression analysis with Spearman's correlation (r) coefficient and intraclass correlation coefficient (ICC)., Results: While high correlation coefficients (r = 0.86, P < 0.001) and substantial agreement (ICC: 0.806, P < 0.001) were observed in patients with IgAN, similar correlations were not observed in patients with MCD or MN-NS. In the patients with MCD, r was 0.53 (P < 0.001), which signified a slight correlation, and in the patients with MN-NS, r was 0.289 (P = 0.17), which was not statistically significant., Conclusions: This study revealed that spot urine PCR is a reliable estimate of 24HP value in patients with IgAN. In contrast, there is a considerable difference between the daily urine protein excretion amount based on a 24-h urine sample and that which is calculated from spot urine PCR in patients with NS.

Background: Previously we found that kidney tissue and urinary exosomes from patients of diabetic kidney disease showed high levels of ceruloplasmin (CP). Because CP is an acute-phase protein of kidney origin, it could be an early marker of many other kidney diseases. To investigate this hypothesis, we first measured urine exosomal and kidney expression of CP in non-diabetic chronic kidney disease (CKD) patients (membranous nephropathy, focal segmental glomerulosclerosis, lupus nephritis and IgA nephropathy) followed by a longitudinal study in rat passive Heymann nephritis (PHN), a model of human membranous nephropathy., Methods: Urinary exosomes were isolated from urine of patients (and rats) by differential centrifugation. The exosomal extracts were used for measuring CP using ELISA. Kidney expression of CP was evaluated by immune-staining biopsy tissues. Similar techniques were applied in rat PHN model (produced by injection of anti-gp600 antiserum) to analyze urine exosomal and kidney CP., Results: Urine exosomal CP levels were 10-20 times higher in CKD patients than in controls; consistent with this we found high immune-reactive CP localized in tubules and collecting ducts of biopsies of CKD patients. In the PHN model urinary exosomal CP level was significantly higher prior to the onset of proteinuria. Early rise of urine exosomal CP, which preceded proteinuria, correlated with high immunoreactive CP found in rat kidneys at this time., Conclusion: We propose that urine exosomal CP, observed to increase prior to proteinuria, makes it a potential urinary biomarker to diagnose early kidney disease.

Introduction: Idiopathic membranous nephropathy (IMN) is a primary glomerular disease and a major cause of adult nephrotic syndrome. Presently, little is known about the capabilities of the urine markers to reflect the severity of IMN. We aimed at establishing whether urinary N-acetyl-β-glucosaminidase (NAG), Retinol binding protein (RBP), Kidney injury molecule-1 (KIM-1) and Neutrophil gelatianse-associated lipocalin (NGAL) are related with renal parameters and the histological grades tubular injury., Methods: The levels of urinary NAG, RBP, KIM-1 and NGAL were determined in 165 biopsy-proven patients and 64 healthy controls. Their levels were then compared between patients and healthy subjects, and between patients with and without nephrotic syndrome. Their linearity with renal parameters and associations with histological grades of renal tubular injury were also assessed., Results: All biomarkers were significantly increased in patients (p < .001). However, no significant increase was observed between patients exhibiting moderate and severe grades tubular injury and those exhibiting mild histological grade. With exception of RBP, all biomarkers were higher in patients with nephrotic syndrome (p < .001) and significantly correlated with majority of renal parameters including proteinuria., Conclusion: Our findings suggest that although urine markers of tubular injury are increased in IMN, they may not offer a reflection of histological grades., (Copyright © 2019. Published by Elsevier B.V.)

Abnormalities of thyroid function are common in patients with nephrotic syndrome (NS). However, a limited number of studies have reported on the association between clinicopathologic features and thyroid dysfunction in patients with NS. We retrospectively studied 317 patients who had been definitively diagnosed with NS. The NS patients with thyroid dysfunction showed higher urine protein, creatinine and lipid levels and lower albumin and hemoglobin than those with normal thyroid function, with no significant differences of pathological types. After dividing thyroid dysfunction groups into five subgroups, interestingly, membranous nephropathy was the most common pathologic type, both in normal thyroid group and in subclinical hypothyroidism group (40.4% and 46.7%, respectively), followed by minimal change disease (28.1% and 21.7%, respectively); while in the hypothyroid, low T3, and low T3T4 groups minimal change disease is now the leading type (48.8%, 33.3% and 38.6%, respectively). High levels of urinary protein, creatinine, cholesterol, and platelets were independent risk factors predicting thyroid dysfunction, while higher albumin and hemoglobin were protective factors. We demonstrated that the type of renal pathology was different among NS patients in different thyroid dysfunction subgroups. Interpretation of the interactions between thyroid and renal function is a challenge for clinicians involved in the treatment of patients with NS.

Nephrotic syndrome with idiopathic membranous nephropathy as a major contributor, is characterized by proteinuria, hypoalbuminemia and oedema. Diagnosis is based on renal biopsy and the condition is treated using immunosuppressive drugs; however nephrotic syndrome treatment efficacy varies among patients. Multi-omic urine analyses can discover new markers of nephrotic syndrome that can be used to develop personalized treatments. For proteomics, a protease inhibitor (PI) is sometimes added at sample collection to conserve proteins but its impact on urine metabolic phenotyping needs to be evaluated. Urine from controls (n = 4) and idiopathic membranous nephropathy (iMN) patients (n = 6) were collected with and without PI addition and analysed using 1H NMR spectroscopy and UPLC-MS. PI-related data features were observed in the 1H NMR spectra but their removal followed by a median fold change normalisation, eliminated the PI contribution. PI-related metabolites in UPLC-MS data had limited effect on metabolic patterns specific to iMN. When using an appropriate data processing pipeline, PI-containing urine samples are appropriate for 1H NMR and MS metabolic profiling of patients with nephrotic syndrome.

Background: Immunosuppressive treatment will predispose an idiopathic membranous nephropathy (iMN) patient to opportunistic infections. Disease severity is one of the main concerns for making the treatment decision. Urinary angiotensinogen (UAGT) level has been shown highly correlated with intrarenal renin-angiotensin system (RAS) activity and severity of chronic kidney diseases (CKD). We aimed to test the relationship between the UAGT level and the severity of iMN., Methods: This cross-sectional study included a total of 48 biopsy-proven iMN patients, 46 minimal change disease (MCD) patients, and 44 healthy volunteers. The clinical and laboratory data and urine samples were collected from all subjects before the use of RAS inhibitors. We determined the UAGT levels with a method of enzyme-linked immunosorbent assay., Results: The UAGT levels were not different between the iMN (277.05 ± 61.25, μg/g.Cr) and MCD patients (244.19 ± 40.24, μg/g.Cr), but both of them were significantly higher than those of healthy controls (6.85 ± 1.10, μg/g.Cr). UAGT levels were correlated negatively with serum albumin (r = - 0.393, p = 0.006) and estimated glomerular filtration rate (eGFR) (r = - 0.352, p = 0.014) and positively with 24-h proteinuria (r = 0.614, p < 0.001) in iMN patients but not in MCD patients. Multivariate linear regression analysis revealed that only proteinuria independently determinate the levels of UAGT (β = 0.649, p < 0.001) in iMN patients., Conclusions: UAGT levels were correlated negatively with serum albumin and glomerular filtration rate and positively with proteinuria in iMN patients at the onset. This suggests that elevated levels of UAGT are associated with the severity of iMN. The UAGT level may be used as a cofactor for deciding immunosuppressive therapy in iMN patient.

BACKGROUND M-type phospholipase A2 receptor (PLA2R) was identified as the major target antigen in idiopathic membranous nephropathy (IMN). Another target antigen, namely thrombospondin type-1 domain-containing 7A (THSD7A), was recently detected in approximately 10% of non-PLA2R-associated IMN. In this single center retrospective study, clinical and histological features of PLA2R-associated and THSD7A-associated IMN patients were evaluated. MATERIAL AND METHODS A total of 192 IMN patients, who were receiving no glucocorticoids or immunosuppressant before renal biopsy, were enrolled in this study and followed for a median duration of 25.5 months. IMN with enhanced glomerular PLA2R and THSD7A staining by immunohistochemistry (IHC) were designated as PLA2R-associated IMN and THSD7A-associated IMN respectively. Serum anti-PLA2R and anti-THSD7A antibodies levels were assessed by enzyme linked immunosorbent assay and indirect immunofluorescence testing in PLA2R-associated and THSD7A-associated IMN. RESULTS Of 192 IMN patients, 164 patients (85.4%) had PLA2R-associated IMN and 3 patients (1.6%) had THSD7A-associated IMN. Compared with non-PLA2R-associated IMN patients, the 24-hour urinary protein levels were significantly higher (P=0.008), whereas, the proteinuria remission rates were significantly lower (P=0.03) in PLA2R-associated IMN patients. No pathological differences were found between PLA2R-associated IMN and non-PLA2R-associated IMN. Among 3 THSD7A-associated IMN patients, 1 patient had elevated serum anti-THSD7A antibody levels, which was below detectable levels after achieving partial proteinuria remission with combined glucocorticoid and cyclosporine treatment. CONCLUSIONS Compared with non-PLA2R-associated IMN patients in our cohort, PLA2R-associated IMN patients presented with more severe proteinuria and lower remission rates after treatment, with no distinct histological differences. Glomerular expression of PLA2R could be a useful marker to indicate the severity, treatment response, and prognosis of IMN.

Recent studies have indicated that urinary sediment miRNAs not only are able to serve as non-invasive diagnostic biomarkers for IgA nephropathy (IgAN) but may also be closely related to several clinical and pathological indicators. However, the lack of a suitable internal reference miRNA has hampered research into urinary sediment miRNAs. To date, U6 has been used as a reference gene in urinary sediment miRNA studies mostly based on the results from studies using tissue samples and cell lines. In a total of 330 IgAN patients, 164 disease control patients and 130 normal control patients, there was no significant difference in U6 levels. We also compared the U6 levels in different types of primary glomerular disease groups (IgA nephropathy, membranous nephropathy, minimal change nephrosis and focal segmental glomerular sclerosis). The results confirmed that there was no significant difference in the expression of U6 in different primary glomerular disease groups. Moreover, treatment had no significant effect on the expression levels of U6 in IgA nephropathy. Therefore, U6 is an excellent housekeeping gene for urinary sediment miRNA studies of IgA nephropathy.

Purpose of Review: To update and evaluate the current knowledge on pathogenesis and management of light chain cast nephropathy. Light chain cast nephropathy (LCCN) is the leading cause of acute renal failure in patients with multiple myeloma and is currently recognized as a myeloma defining event., Recent Findings: The immunoglobulin free light chain plays an integral role in the pathogenesis of LCCN. The level of free light chain (FLC) in the blood and urine is directly associated with the risk of developing LCCN. Recovery of renal function is related to the speed and degree of the serum FLC reduction. Recently, two randomized trials using high cutoff dialyzer for the removal of serum FLC produced different results in terms of renal recovery. FLC plays a key role in the development and resolution of LCCN. Future therapies will aim to rapidly reduce its concentration or interrupt its interaction with Tamm-Horsfall protein.

Biomarkers required to assess accurately the prognosis of idiopathic membranous nephropathy (IMN) are still unavailable. A retrospective study on 156 IMN patients showed only urinary IL-8 was associated with the achievement of initial complete remission (CR) in IMN patients. A urinary IL-8 level of less than 61.25 pg/mL was more sensitive for prediction of CR in IMN patients. Therefore, urinary IL-8 may be a potential biomarker for evaluating short-term prognosis of IMN patients., (© 2018 Royal Australasian College of Physicians.)

Aim: The clinical course of idiopathic membranous nephropathy (IMN) varies from spontaneous remission of nephrotic syndrome (NS) to end-stage renal disease (ESRD). The aim of the study was baseline identification of patients with high risk of progression for which immunosuppressive therapy is mandatory., Methods: Eighty-six IMN subjects were followed for a median of 69 months (range 6-253). Receiver operating characteristic curve and Cox proportional hazards model were used to evaluate prognostic factors for progression, defined as ESRD or estimated glomerular filtration rate (eGFR) reduction ≥50% of baseline., Results: Among all, 24 subjects had progression. Area under the ROC curve of N-acetyl-β-glucosaminidase/creatinine ratio (NAG/C) were significantly higher than proteinuria/24 h (0.770 and 0.637 respectively, P = 0.018). In Cox proportional hazards regression analysis, NAG/C and eGFR were independent predictors of progression. Compared to lowest tertile of NAG/C (<9.4 UI/gC) or highest tertile of eGFR (≥88 mL/min per 1.73m 2 ), the multivariable-adjusted hazard ratio of highest tertile of NAG/C (≥19.2) was 18.97 (95%CI, 1.70-211.86) and lowest tertile of eGFR (<59) was 11.58 (95%CI, 2.02-66.29). Subjects with high NAG/C or low eGFR (high-risk, n = 43) had greater progression rate compared to moderate to low NAG/C and high eGFR (low-risk, n = 43) with or without NS at baseline (Log-rank test P = 0.001 and 0.006, respectively). In NS subjects (n = 65), high-risk group progression rate was significantly higher (91% vs. 29%, P = 0.003) and remission rate significantly lower (0% vs. 42%, p < 0.001) in non-immunosuppressed compared to steroids and cyclophosphamide treated patients; no significant differences were observed in low-risk group., Conclusion: Idiopathic membranous nephropathy subjects with high NAG/C and low eGFR have greater risk of progression, and immunosuppressive treatment is suggested at diagnosis., (© 2016 Asian Pacific Society of Nephrology.)

Background: Several registries and centers have reported the results of renal biopsies from different parts of the world. As there are few data regarding the epidemiology of glomerulonephritis (GN) in South Korea, we conducted this study on renal biopsy findings during the last 20 years from a single center., Methods: Data for 818 patients who underwent renal biopsy at our center between 1992 and 2011 were collected retrospectively. All kidney specimens were examined with light microscopy (LM) and immunofluorescent microscopy (IF)., Results: There were 818 cases of native kidney biopsies. In cases of primary GN, the most frequent type of renal pathology in adults (18-59 years) was mesangial proliferative GN (MsPGN, 34.5%) followed by IgA nephropathy (IgAN, 33.3%) and membranous GN (MGN, 8.8%). Indications in adults (18-59 years) were asymptomatic urinary abnormalities (75.3%) followed by nephrotic syndrome (19.8%) and acute kidney injury (AKI, 3.4%)., Conclusions: Among 818 renal biopsy specimens, MsPGN and IgAN were the most frequent biopsy-proven renal diseases. MGN was the third most common cause of primary GN and lupus nephritis (LN) was the most common secondary glomerular disease. Our data contribute to the epidemiology of renal disease in South Korea.

Introduction: The purpose of the study is to evaluate the efficiency and safety of tacrolimus (TAC) monotherapy in the treatment of nephrotic idiopathic membranous nephropathy (IMN) compared with the protocol of cyclophosphamide (CTX) combined with corticosteroids., Methods: In total, 58 patients with nephrotic syndrome and biopsy-proven IMN were included in this study. 30 patients received TAC monotherapy with an initial dose of 0.05-0.1 mg/kg/day. 28 patients received transvenous CTX at a dose of 0.5-0.75 g/m 2 once in every month initially for 6 months and once in every 2 or 3 months for the later period, and the regimen was combined with corticosteroids (prednisone 1 mg/kg/d). All patients were observed for the treatment effects, recurrence and side effects., Results: Twelve months after the initial treatment, a total of 24 (80%) patients in the TAC group and 23 (82.1%) patients in the CTX group achieved remission (either partial or complete remission). The survival curve of the probability of remission and complete remission were similar between the two groups (p > .05). Proteinuria (based on 24 h urinary protein excretion) was significantly decreased, and serum albumin was significantly increased after immunosuppressive treatment in both the groups. Estimated glomerular filtration rate (eGFR) was comparable between before and after treatment. The main adverse effects in TAC treatment were glucose intolerance, diabetes and abnormal aminotransferase., Conclusions: TAC monotherapy is an alternative therapeutic regimen for patients with nephrotic IMN. Its short-term efficiency and patient tolerance are both acceptable.

The pathophysiology of many proteinuric kidney diseases is poorly understood, and microRNAs (miRs) regulation of these diseases has been largely unexplored. Here, we tested whether miR-378a-3p is a novel regulator of glomerular diseases. MiR-378a-3p has two predicted targets relevant to glomerular function, the glomerular basement membrane matrix component, nephronectin (NPNT), and vascular endothelial growth factor VEGF-A. In zebrafish (Danio rerio), miR-378a-3p mimic injection or npnt knockdown by a morpholino oligomer caused an identical phenotype consisting of edema, proteinuria, podocyte effacement, and widening of the glomerular basement membrane in the lamina rara interna. Zebrafish vegf-A protein could not rescue this phenotype. However, mouse Npnt constructs containing a mutated 3'UTR region prevented the phenotype caused by miR-378a-3p mimic injection. Overexpression of miR-378a-3p in mice confirmed glomerular dysfunction in a mammalian model. Biopsies from patients with focal segmental glomerulosclerosis and membranous nephropathy had increased miR-378a-3p expression and reduced glomerular levels of NPNT. Thus, miR-378a-3p-mediated suppression of the glomerular matrix protein NPNT is a novel mechanism for proteinuria development in active glomerular diseases., (Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Background: According to the renal phospholipase A2 receptor (PLA2R) immunohistochemistry, idiopathic membranous nephropathy (iMN) could be categorized into PLA2R-associated and non-PLA2R-associated iMN. This study aimed to examine whether the non-PLA2R-associated iMN had any difference in clinical features compared with PLA2R-associated iMN., Methods: A total of 231 adult patients diagnosed as iMN were recruited to this retrospective study. Renal PLA2R expression was examined by immunofluorescence. Among these patients, 186 (80.5%) with complete baseline clinical data were used for further study. Urinary protein excretion, serum albumin, and creatinine were analyzed. For those patients with follow-up longer than 1 year, the relationship between PLA2R and response to immunosuppressants were analyzed. The t-test was used for parametric analysis and the Mann-Whitney U-test was used for nonparametric analysis. Categorical variables were described as frequencies or percentages, and the data were analyzed with Pearson's Chi-square test or Fisher's exact test., Results: Of the 231 iMN patients, 189 showed renal detectable PLA2R expression (81.8%). The baseline serum creatinine, serum albumin, and urine protein excretion were not significantly different between PLA2R-associated (n = 145) and non-PLA2R-associated iMN patients (n = 41). However, about 1/3 of the non-PLA2R-associated iMN had abnormal serological tests, significantly more common than PLA2R-associated iMN (31.7% vs. 8.3%, P = 0.000). The non-PLA2R-associated iMN had lower C4 levels compared with PLA2R-associated iMN (P = 0.004). The non-PLA2R-associated iMN patients also showed a better response to immunosuppressants (complete remission [CR] 42.9%; partial remission [PR] 14.3%) compared with PLA2R-associated iMN (CR 3.2%; PR 48.4%, P = 0.004) at the 3rd month., Conclusions: There were no significant differences in serum creatinine, albumin, and urine protein excretion between PLA2R-associated and non-PLA2R-associated iMN, while the non-PLA2R-associated iMN patients showed more abnormal serological tests. The non-PLA2R-associated iMN seemed to respond more quickly to the immunosuppressive therapy compared with PLA2R-associated iMN.

This case report discusses the clinical indication for immunosuppressants in patients with idiopathic membranous nephropathy (IMN). Because this disease occasionally shows spontaneous remission, it is necessary to determine the predictive values for a therapeutic effect in order to provide appropriate treatment. Two distinct cases described herein illustrate the different effects of tolvaptan in responders and non-responders, according to the pre-treatment levels of AQP-2 immunostaining in the samples from renal biopsy and urinary levels of AQP-2 and osmolality, suggesting that these values may be useful predictors of response to tolvaptan in patients with nephrotic IMN.

Objective: To detect urinary volatile organic compounds (VOCs) in patients with idiopathic membranous nephropathy (iMN) and normal controls, and to examine whether or not urinary VOCs can act as biomarkers for the diagnosis of iMN independent of renal biopsy., Materials and Methods: Gas chromatography/mass spectrometry (GC/MS) was used to assess the urine collected from 63 iMN patients and 15 normal controls. The statistical methods of principal component analysis and partial least squares discriminant analysis were performed to process the final data in Common Data Format which were converted from GC/MS data., Results: Six VOCs in the urine samples of iMN patients exhibited significant differences from those of normal controls: carbamic acid monoammonium salt, 2-pentanone, 2,4-dimethyl-pentanal, hydrogen azide, thiourea, and 4-heptanone were significantly higher than in controls (p < 0.05)., Conclusions: Six urinary VOCs were isolated from patients with iMN using GC/MS. The analysis of urinary VOCs using GC/MS could be developed into a non-invasive method for the detection of iMN., (© 2017 The Author(s) Published by S. Karger AG, Basel.)

Introduction: High-mobility group box 1 protein (HMGB-1) has been implicated in the pathogenesis of lupus nephritis (LN). There is increased HMGB-1 expression in the kidneys and increased levels are observed in serum and urine of patients with LN. This study was performed to determine whether the increased urinary HMGB-1 was specific for active lupus or secondary to renal damage., Methods: Urine from 61 lupus patients (32 had active LN and 29 had systemic lupus erythematosus (SLE) with no evidence of LN) and 14 control proteinuric patients (all with hypertension and eight also with diabetes) were included in this study. HMGB-1 was detected by Western blot. Urine protein was normalized to urine creatinine to account for volume of the specimen., Results: Median normalized urine HMGB-1 levels were significantly elevated in LN patients compared to lupus patients without kidney disease (53.81 vs 9.46, p < 0.001). A difference in median levels was seen between LN classes, with a significant difference between proliferative and membranous disease (33.4 vs 138.8, p = 0.003). Urine protein to urine creatinine ratio (P/C) correlated with urinary HMGB-1 (r = 0.52, p < 0.001), but across the classes this was true only for membranous disease (r = 0.71, p = 0.022, proliferative, p = 0.63; mixed, p = 0.34)., Conclusions: HMGB-1 is elevated in the urine of patients with active LN. Levels are associated with LN class, and higher levels of urinary HMGB-1 are seen in patients with class V when compared to both proliferative and mixed classes. Therefore, urinary HMGB-1 may be suggestive of membranous LN and warrants further evaluation in a large lupus cohort., Competing Interests: statement The Authors declare that there is no conflict of interest, (© The Author(s) 2016.)

The goal of this study is to identify systematic biomarker panel for primary nephrotic syndromes from urine samples by applying a non-target metabolite profiling, and to validate their utility in independent sampling and analysis by multiplex statistical approaches. Nephrotic syndrome (NS) is a nonspecific kidney disorder, which is mostly represented by minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), and membranous glomerulonephritis (MGN). Since urine metabolites may mirror disease-specific functional perturbations in kidney injury, we examined urine samples for distinctive metabolic changes to identify biomarkers for clinical applications. We developed unbiased multi-component covarianced models from a discovery set with 48 samples (12 healthy controls, 12 MCD, 12 FSGS, and 12 MGN). To extensively validate their diagnostic potential, new batch from 54 patients with primary NS were independently examined a year after. In the independent validation set, the model including citric acid, pyruvic acid, fructose, ethanolamine, and cysteine effectively discriminated each NS using receiver operating characteristic (ROC) analysis except MCD-MGN comparison; nonetheless an additional metabolite multi-composite greatly improved the discrimination power between MCD and MGN. Finally, we proposed the re-constructed metabolic network distinctively dysregulated by the different NSs that may deepen comprehensive understanding of the disease mechanistic, and help the enhanced identification of NS and therapeutic plans for future., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Urinary excretion of alpha-1-microglobulin and beta-2-microglobulin reflects tubular damage and predicts outcome in patients with idiopathic membranous nephropathy with reasonable accuracy. Urinary kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin are novel biomarkers of tubular damage. We investigated if these markers could improve prediction of outcome in idiopathic membranous nephropathy., Methods: We measured kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin in urine samples from patients with idiopathic membranous nephropathy, who had nephrotic proteinuria and normal renal function. Excretion of alpha-1-microglobulin and beta-2-microglobulin had been measured previously. Progression was defined as a serum creatinine rise >30%, a rise in serum creatinine to an absolute value of ≥135 µmol/L, or a clinical decision to start immunosuppressive therapy. Remission was defined as proteinuria <3.5 g/day and >50% reduction from baseline., Results: Sixty-nine patients were included. Median follow-up was 35 months (interquartile range 18-63 months). Progression occurred in 30 patients (44%), and spontaneous remission in 36 (52%). Kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin excretion rates were significantly correlated with each other, and with alpha-1-microglobulin and beta-2-microglobulin. The areas under the receiver operating characteristic curves for progression were 0.75 (0.62-0.87) for kidney injury molecule-1 and 0.74 (0.62-0.87) for neutrophil gelatinase-associated lipocalin. In multivariate analysis with either alpha-1-microglobulin and beta-2-microglobulin, kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin did not independently predict outcome., Conclusion: Kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin excretion rates correlated with excretion rates of other tubular damage markers and predicted outcome in patients with idiopathic membranous nephropathy. They did not add prognostic value compared to measurement of either alpha-1-microglobulin or beta-2-microglobulin., (© The Author(s) 2015.)

Urinary microvesicles constitute a rich source of membrane-bound and intracellular proteins that may provide important clues of pathophysiological mechanisms in renal disease. In the current study, we analyzed and compared the proteome of urinary microvesicles from patients with idiopathic membranous nephropathy (iMN), idiopathic focal segmental glomerulosclerosis (iFSGS), and normal controls using an approach that combined both proteomics and pathology analysis. Lysosome membrane protein-2 (LIMP-2) was increased greater than twofold in urinary microvesicles obtained from patients with iMN compared to microvesicles of patients with iFSGS and normal controls. Immunofluorescence analysis of renal biopsies confirmed our proteomics findings that LIMP-2 was upregulated in glomeruli from patients with iMN but not in glomeruli of diseased patients (iFSGS, minimal change nephropathy, IgA nephropathy, membranoproliferative glomerulonephritis) and normal controls. Confocal laser microscopy showed co-localization of LIMP-2 with IgG along the glomerular basement membrane. Serum antibodies against LIMP-2 could not be detected. In conclusion, our data show the value of urinary microvesicles in biomarker discovery and provide evidence for de novo expression of LIMP-2 in glomeruli of patients with iMN., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: This study aimed to describe the influences of larger physical constitutions including obesity on the amount of urine protein excretion (AUPE) in primary glomerulonephritis. The distinct effects on the AUPE in various types of glomerulonephritis were evaluated., Methods: Using the database of the Japan Renal Biopsy Registry (J-RBR) from 2007 to 2010, 4060 cases with primary glomerulonephritis including MCNS, FSGS, MN, MPGN, IgAN, and non-IgA were reviewed. The AUPEs were compared between high and low Body Mass Index (BMI) groups, and larger and smaller body surface area (BSA) groups using the indexes of BMI 25.0 kg/m(2) and BSA 1.73 m(2) in all cases and in each histological group. Multivariable analysis was performed to evaluate the predominant contributors to the AUPE., Results: The larger physical constitution groups (BMI ≥25.0 kg/m(2) or BSA ≥1.73 m(2)) had significantly higher AUPEs in all cases with primary glomerulonephritis. When compared in each histological group, the mean AUPEs were significantly higher in the larger physical constitution groups, excluding the FSGS and non-IgA groups. Multiple regression analysis revealed that the significant contributors to the AUPE were BMI and BSA in MCNS and MN, whereas BMI and BSA were not significant and mean blood pressure and serum creatinine were significant in FSGS and non-IgA., Conclusion: Larger physical constitutions including obesity had a significant impact on the increase in the AUPE in primary glomerulonephritis, especially in MCNS and MN. However, FSGS and non-IgA were distinct for having blood pressure and renal dysfunction as possibly the major causes of proteinuria.

Objective: The presence of antibodies against the M-type phospholipase A2 receptor (PLA2RAb) is considered to be a promising serological diagnostic biomarker of idiopathic membranous nephropathy (IMN). We compare the change in serum Cystain C (CysC), urea, creatinine (CREA), uric acid (UA), total protein (TP), albumin (ALB), IgG4 and 24-h urinary protein (proteinuria, PRO) between PLA2RAb+ and PLA2RAb- of IMN patients., Materials and Methods: The serum and urine samples were collected from 120 patients with IMN. The presence of circulating PLA2RAb was determined by indirect immunofluorescence, and their titer was quantified by ELISA. CysC, urea, CREA, UA, TP, ALB and 24-h PRO were examined by automatic biochemical analyzer., Results: Serum IgG4 level was determined by specific protein analyzer. PLA2RAb-positive percentage by ELISA was higher than that by IIF, but no significant difference was found by McNemar's Chi-square test. Serum IgG4 level and 24-h PRO level were significantly higher in PLA2RAb+ than in PLA2RAb- (P < 0.05). In PLA2RAb+ group, PLA2RAb is positively related to serum IgG4 and 24-h PRO and negatively related to serum TP and ALB (P < 0.01)., Conclusion: This is the first study to show that combined detection of IgG4 concentration and PLA2RAb was usable for IMN patients.

It has been suggested that soluble urokinase receptor (suPAR) is a causative circulating factor for and a biomarker of focal and segmental glomerulosclerosis (FSGS). Here we undertook validation of these assumptions in both mouse and human models. Injection of recombinant suPAR in wild-type mice did not induce proteinuria within 24 h. Moreover, a disease phenotype was not seen in an inducible transgenic mouse model that maintained elevated suPAR concentrations for 6 weeks. Plasma and urine suPAR concentrations were evaluated as clinical biomarkers in 241 patients with glomerular disease from the prospective, longitudinal multicenter observational NEPTUNE cohort. The serum suPAR concentration at baseline inversely correlated with estimated glomerular filtration rate (eGFR) and the urine suPAR/creatinine ratio positively correlated with the urine protein/creatinine ratio. After adjusting for eGFR and urine protein, neither the serum nor urine suPAR level was an independent predictor of FSGS histopathology. A multivariable mixed-effects model of longitudinal data evaluated the association between the change in serum suPAR concentration from baseline with eGFR. After adjusting for baseline suPAR concentration, age, gender, proteinuria, and time, the change in suPAR from baseline was associated with eGFR, but this association was not different for patients with FSGS as compared with other diagnoses. Thus these results do not support a pathological role for suPAR in FSGS.

Podocyte damage and loss together have an important role in the pathogenesis and progression of glomerulonephritis. Glomerulonephritis patients and healthy controls were enrolled in this study. Biochemical, clinical and experimental procedures included measurement of total urinary protein, renal biopsy and gene expression analysis of the receptor activator of NF-kappaB (RANK). The urinary mRNA levels of RANK were significantly higher in the glomerulonephritis group compared to the controls. The urinary RANK level of glomerular subtypes was correlated significantly with proteinuria. The calculated area of RANK mRNA levels under the curve was 0.61 for minimal change disease (MCD), 0.97 for membranous nephropathy (MN), 0.65 for IgA nephropathy (IgAN), 0.70 for lupus nephritis (LN) and 0.70 for focal segmental glomerulosclerosis (FSGS). The urinary mRNA of RANK might be used to differentiate histologic subtypes of glomerulonephritis, particularly between MCD and MN.

Background: Idiopathic membranous nephropathy (IMN) is increasingly seen in older patients. However, differences in disease presentation and outcomes between older and younger IMN patients remain controversial. We compared patient characteristics between younger and older IMN patients., Methods: We recruited 171 Japanese patients with IMN, including 90 (52.6%) patients <65 years old, 40 (23.4%) patients 65-70 years, and 41 (24.0%) patients ≥ 71 years. Clinical characteristics and outcomes were compared between younger and older IMN patients., Results: During a median observation period of 37 months, 103 (60.2%) patients achieved complete proteinuria remission, which was not significantly associated with patient age (P = 0.831). However, 13 (7.6%) patients were hospitalized because of infection. Multivariate Cox proportional hazards models identified older age [adjusted hazard ratio (HR) = 3.11, 95% confidence interval (CI): 1.45-7.49, per 10 years; P = 0.003], prednisolone use (adjusted HR = 11.8, 95% CI: 1.59-242.5; P = 0.014), and cyclosporine used in combination with prednisolone (adjusted HR = 10.3, 95% CI: 1.59-204.4; P = 0.012) as significant predictors of infection. A <25% decrease in proteinuria at 1 month after immunosuppressive therapy initiation also predicted infection (adjusted HR = 6.72, 95% CI: 1.51-37.8; P = 0.012)., Conclusions: Younger and older IMN patients had similar renal outcomes. However, older patients were more likely to develop infection when using immunosuppressants. Patients with a poor response in the first month following the initiation of immunosuppressive therapy should be carefully monitored for infection and may require a faster prednisolone taper.

Membranous nephropathy (MN), a type of glomerular nephritis, is the most common cause of nephrotic syndrome in human adults. Changes in gene expression as a result of epigenetic dysregulation through long noncoding RNAs (lncRNAs) are increasingly being recognized as important factors in disease. Using an experimental MN mouse model, we identify the first dysregulated lncRNAs, Xist and NEAT1, whose levels are significantly upregulated in both tubular epithelial and glomerular cells. MN is also often characterized by glomerular podocyte injury. Treatment of a mouse podocyte cell line with lipopolysaccharides to induce injury resulted in the stable elevation of Xist, but not NEAT1 levels. In mice, the observed changes in Xist levels are specific: Xist can be effectively detected in urine, with a strong correlation to disease severity, but not serum in MN samples. We find that regulation of Xist may be controlled by post-translational modifications. H3K27me3 levels are significantly downregulated in mouse MN kidney, where chromatin immunoprecipitation experiments also showed decreased H3K27me3 at Xist promoter regions. Finally, we show that our findings in mice can be extended to human clinical samples. Urinary Xist is significantly elevated in urine samples from patients with different types of glomerular nephritis, including MN, compared to normal counterparts. Together, our results suggest that a reduction of H3K27me3 at Xist promoter regions leads to elevated levels of urinary Xist, which may be used as a biomarker to detect MN., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Aim: To assess the effectiveness of supine/standing urinalysis for differential diagnosis of left renal vein entrapment syndrome (LRVES) combined with or without glomerulopathy., Methods: The enrolled patients with abnormal urinalysis and LRVES demonstrated by Doppler sonography were guided to perform a supine/standing urinalysis., Results: Fifty-two patients were enrolled. Most of them were adolescents (aged 14-29 years, 73.1%) and with low body mass index (BMI, mean BMI, 19.8 ± 2.4 kg/m(2)). Seventeen cases (32.7%) manifested orthostatic urine abnormalities (OUA, proteinuria and/or haematuria show negative in supine while positive after 15 min standing), two patients who had undergone renal biopsies both showed no evidence of kidney lesions, another two patients were changed from abnormal to normal urinalysis after weight gain. The remaining 35 cases (67.3%) manifested non-orthostatic urine abnormalities (NOUA, proteinuria and/or haematuria show positive both in supine and standing), 15 patients had undergone renal biopsies and showed different degrees of glomerulopathy. After prednisone/immunosuppression therapy, four patients with glomerulonephritis were changed from the NOUA to the OUA classification. Statistics analyses showed that serum total protein and albumin levels were significantly lower (P = 0.028, 0.007, respectively) and urinary protein was significantly higher (P = 0.007) in the NOUA group than in the OUA group., Conclusion: After the indication of LRVES by ultrasound, patients with OUA likely have only LRVES, while patients with NOUA likely also have glomerulopathy. Supine/standing urinalysis combined with Doppler sonography can be helpful for differential diagnosis of LRVES combined with or without glomerulopathy., (© 2014 Asian Pacific Society of Nephrology.)

Background: Focal segmental glomerulosclerosis (FSGS) is a major cause of end-stage renal disease. Recent studies have proposed that plasma soluble urokinase receptor (suPAR) might be a causative circulating factor but this proposal has caused controversy. This study aimed to measure urinary suPAR levels in patients with primary FSGS and its significance in the pathogenesis of FSGS., Methods: Sixty-two patients with primary FSGS, diagnosed between January 2006 and January 2012, with complete clinical and pathologic data were enrolled, together with disease and normal controls. Urinary suPAR levels were measured using commercial ELISA kits and were corrected by urinary creatinine (Cr). The associations between urinary suPAR levels and clinical data at presentation and during follow up were analyzed. Conditionally immortalized human podocytes were used to study the effect of urinary suPAR on activating β3 integrin detected by AP5 staining., Results: The urinary suPAR level of patients with primary FSGS (500.56, IQR 262.78 to 1,059.44 pg/μmol Cr) was significantly higher than that of patients with minimal change disease (307.86, IQR 216.54 to 480.18 pg/μmol Cr, P = 0.033), membranous nephropathy (250.23, IQR 170.37 to 357.59 pg/μmol Cr, P <0.001), secondary FSGS (220.45, IQR 149.38 to 335.54 pg/μmol Cr, P <0.001) and normal subjects (183.59, IQR 103.92 to 228.78 pg/μmol Cr, P <0.001). The urinary suPAR level of patients with cellular variant was significantly higher than that of patients with tip variant. The urinary suPAR level in the patients with primary FSGS was positively correlated with 24-hour urine protein (r = 0.287, P = 0.024). During follow up, the urinary suPAR level of patients with complete remission decreased significantly (661.19, IQR 224.32 to 1,115.29 pg/μmol Cr versus 217.68, IQR 121.77 to 415.55 pg/μmol Cr, P = 0.017). The AP5 signal was strongly induced along the cell membrane when human differentiated podocytes were incubated with the urine of patients with FSGS at presentation, and the signal could be reduced by a blocking antibody specific to uPAR., Conclusions: Urinary suPAR was specifically elevated in patients with primary FSGS and was associated with disease severity. The elevated urinary suPAR could activate β3 integrin on human podocytes.