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Kwon CS, Daniele P, Forsythe A, Ngai C. A Systematic Literature Review of the Epidemiology, Health-Related Quality of Life Impact, and Economic Burden of Immunoglobulin A Nephropathy. JOURNAL OF HEALTH ECONOMICS AND OUTCOMES RESEARCH 2021. [PMID: 34692885 DOI: 10.36469/jheor.2021.26129] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Introduction: This systematic literature review analyzed published evidence on IgA nephropathy (IgAN), focusing on US epidemiology, health-related quality of life (HRQoL), and economic burden of illness. Methods: Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Embase®, MEDLINE®, Cochrane, and Econlit (January 2010 to June 2020) were searched, along with relevant congresses (2017-2020). Results: Of 123 epidemiologic studies selected for data extraction, 24 reported IgAN diagnosis rates ranging from 6.3% to 29.7% among adult and pediatric patients undergoing renal biopsy, with all reported US rates <15%. No US studies reported IgAN prevalence. A meta-analysis of US studies calculated an annual incidence of 1.29/100 000 people, translating to an annual US incidence of 4236 adults and children. Relative to Europe, the United States had more patients diagnosed with IgAN in later chronic kidney disease stages. US rates of transition to end-stage renal disease (ESRD) ranged from 12.5% to 23% during 3-3.9 years of observation, rising to 53% during 19 years of observation. Across 8 studies reporting HRQoL, pain and fatigue were the most reported symptoms, and patients consistently ranked kidney function and mortality as the most important treatment outcomes. Patients with glomerulopathy reported worse mental health than healthy controls or hemodialysis patients; proteinuria was significantly associated with poorer HRQoL and depression. Conclusion: While economic evidence in IgAN remains sparse, management of ESRD is a major cost driver. IgAN is a rare disease where disease progression causes increasing patient burden, underscoring the need for therapies that prevent kidney function decline and HRQoL deterioration while reducing mortality.
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Clinical Relevance of Serum Galactose Deficient IgA1 in Patients with IgA Nephropathy. J Clin Med 2020; 9:jcm9113549. [PMID: 33158064 PMCID: PMC7694202 DOI: 10.3390/jcm9113549] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/30/2020] [Accepted: 11/03/2020] [Indexed: 12/30/2022] Open
Abstract
New biomarkers of IgA nephropathy (IgAN) are needed for non-invasive diagnosis and appropriate treatment. There is emerging evidence that galactose deficient IgA1 (Gd-IgA1) is a pivotal molecule in the pathogenesis of IgAN. However, few studies have investigated the role of Gd-IgA1 as a biomarker in IgAN. In this study, we investigated the clinical relevance of serum Gd-IgA1 levels in patients with IgAN. Two hundred and thirty biopsy-proven IgAN patients, 74 disease controls (patients with non-IgAN nephropathy), and 15 healthy controls were enrolled in this study. Levels of serum Gd-IgA1 were measured using an ELISA kit in serum samples obtained the day of renal biopsy. We compared levels of serum Gd-IgA1 according to the type of glomerular disease and analyzed the association between Gd-IgA1 levels and clinical and pathological parameters in patients with IgAN. We then divided IgAN patients into two groups according to Gd-IgA1 level and investigated the predictive value of Gd-IgA1 for progression of chronic kidney disease (CKD). Serum Gd-IgA1 levels were significantly higher in IgAN patients than disease controls and healthy controls. In patients with IgAN, serum Gd-IA1 levels were significantly correlated with estimated glomerular filtration rate, serum IgA level, and tubular atrophy/interstitial fibrosis. CKD progression was more frequent in IgAN patients with higher serum Gd-IgA1 levels than in those with lower serum Gd-IgA1 levels. Cox proportional hazard models showed that high GdIgA1 level was an independent risk factor for CKD progression after adjusting for several confounders. Our results suggest that serum Gd-IgA1 level is a useful diagnostic and prognostic marker in IgAN patients. Further studies with a larger sample size and longer follow-up duration are needed.
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Lafayette RA, Rovin BH, Reich HN, Tumlin JA, Floege J, Barratt J. Safety, Tolerability and Efficacy of Narsoplimab, a Novel MASP-2 Inhibitor for the Treatment of IgA Nephropathy. Kidney Int Rep 2020; 5:2032-2041. [PMID: 33163724 PMCID: PMC7609886 DOI: 10.1016/j.ekir.2020.08.003] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/11/2020] [Accepted: 08/04/2020] [Indexed: 12/20/2022] Open
Abstract
Introduction Narsoplimab is a human monoclonal antibody against mannan-associated lectin-binding serine protease−2 (MASP-2). Now in a phase 3 study, narsoplimab was evaluated in a staged phase 2 study assessing safety and effectiveness in high-risk patients with IgA nephropathy (IgAN). Methods Substudy 1 was a single-arm open-label study of 12 weekly infusions and tapered corticosteroids, with 6 weeks of follow-up. In substudy 2, patients were randomized 1:1 to receive a course of treatment consisting of once-weekly narsoplimab or vehicle infusions for 12 weeks. After 6 weeks of follow-up, both substudy 2 groups could continue in an open-label extension, receiving 1 or more narsoplimab courses at the investigator’s discretion. Results The most commonly reported adverse events (AEs) included headache, upper respiratory infection, and fatigue. Most AEs were mild or moderate and transient. No treatment-related serious AEs were reported. All 4 patients who were enrolled in substudy 1 had reductions in 24-hour urine protein excretion (UPE) at week 18, ranging from 54% to 95% compared with baseline. In substudy 2, the vehicle and narsoplimab groups had similar proteinuria reductions at week 18. Eight patients (3 vehicle, 5 narsoplimab) continued in the dosing extension; all received narsoplimab. Median reduction in 24-hour UPE in these 8 patients was 61.4% at 31 to 54 weeks postbaseline. Estimated glomerular filtration rates (eGFR) remained stable in both substudies. Conclusion This interim analysis suggests that narsoplimab treatment is safe, is well tolerated, and may result in clinically meaningful reductions in proteinuria and stability of eGFR in high-risk patients with advanced IgAN.
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Affiliation(s)
- Richard A. Lafayette
- Division of Nephrology, Department of Medicine, Stanford University, Stanford, California, USA
- Correspondence: Richard A. Lafayette, Division of Nephrology, Department of Medicine, Stanford University, Stanford, California 94305, USA.
| | - Brad H. Rovin
- Division of Nephrology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Heather N. Reich
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - James A. Tumlin
- NephroNet Clinical Research Consortium, Atlanta, Georgia, USA
| | - Jürgen Floege
- Department of Nephrology and Clinical Immunology, RWTH Aachen University Hospital, Aachen, Germany
| | - Jonathan Barratt
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK
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Faria B, Canão P, Cai Q, Henriques C, Matos AC, Poppelaars F, Gaya da Costa M, Daha MR, Silva R, Pestana M, Seelen MA. Arteriolar C4d in IgA Nephropathy: A Cohort Study. Am J Kidney Dis 2020; 76:669-678. [PMID: 32439421 DOI: 10.1053/j.ajkd.2020.03.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 03/10/2020] [Indexed: 12/20/2022]
Abstract
RATIONALE & OBJECTIVE Glomerular C4d (C4dG) as an indicator of the lectin pathway of complement activation in immunoglobulin A nephropathy (IgAN) has been associated with more severe kidney damage. Recent studies have suggested that vascular lesions in IgAN biopsy specimens with complement deposition are also associated with disease progression. We aimed to study the clinical significance of arteriolar C4d (C4dA) in IgAN kidney biopsy tissue. STUDY DESIGN Retrospective cohort study. SETTING & PARTICIPANTS Kidney biopsy specimens from 126 adults with IgAN diagnosed by Oxford classification criteria were stained using immunohistochemistry and classified according to C4dG and C4dA deposition. Additionally, vascular lesions including acute and chronic microangiopathy, arteriolar hyalinosis, and arterial intima fibrosis were characterized. PREDICTOR C4dA. OUTCOME Progressive kidney disease, defined as a decline in estimated glomerular filtration rate by≥50% or occurrence of kidney failure. ANALYTICAL APPROACH The association of C4dA and C4dG with baseline clinical and histologic characteristics, as well as progressive kidney disease, were assessed with survival analysis using multivariable Cox regression analysis. RESULTS C4dA was identified in 21 (17%) patients and was associated with mean arterial pressure, arterial intima fibrosis, and chronic microangiopathy. C4dA was also significantly associated with C4dG and both were associated with progressive kidney disease. In regression analysis, C4dA remained significantly associated with progressive kidney disease after adjusting for other significant predictors, including baseline estimated glomerular filtration rate, mean arterial pressure, and the presence of crescents. LIMITATIONS Findings based on the retrospective evaluation of a single center's experience, limited number of events, a small number of patients with a broad range of kidney disease stages, and use of immunohistochemistry rather than immunofluorescence to detect C4d. CONCLUSIONS C4dA is a potential biomarker for disease progression in IgAN. It should be further investigated in larger cohorts to determine the value of C4dA in improving prediction of IgAN disease progression.
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Affiliation(s)
- Bernardo Faria
- Nephrology and Infectious Disease R&D Group, INEB, Institute of Investigation and Innovation in Health (i3S), University of Porto, Porto, Portugal; Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
| | - Pedro Canão
- Department of Anatomic Pathology, Centro Hospitalar Universitário São João, Porto
| | - Qingqing Cai
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Carla Henriques
- School of Technology and Management, Polytechnic Institute of Viseu, Viseu; Centre for Mathematics, University of Coimbra (CMUC), Coimbra
| | - Ana Cristina Matos
- School of Technology and Management, Polytechnic Institute of Viseu, Viseu; Centre for Research in Digital Services and CISeD, Viseu, Portugal
| | - Felix Poppelaars
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Mariana Gaya da Costa
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Mohamed R Daha
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands; Department of Nephrology, University of Leiden, Leiden University Medical Center, Leiden, the Netherlands
| | - Roberto Silva
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Manuel Pestana
- Nephrology and Infectious Disease R&D Group, INEB, Institute of Investigation and Innovation in Health (i3S), University of Porto, Porto, Portugal; Division of Nephrology, Centro Hospitalar Universitário São João and Department of Medicine, Faculty of Medicine of Porto University, Porto, Portugal
| | - Marc A Seelen
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
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Li P, Lin H, Ni Z, Zhan Y, He Y, Yang H, Fang J, Wang N, Li W, Cai G, Chen Y, Zhang P, Wang X, Chen Q, Li Z, Sun X, Chen X. Efficacy and safety of Abelmoschus manihot for IgA nephropathy: A multicenter randomized clinical trial. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2020; 76:153231. [PMID: 32535481 DOI: 10.1016/j.phymed.2020.153231] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 04/03/2020] [Accepted: 04/17/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE AND OBJECTIVE IgA nephropathy (IgAN) is an important cause for end-stage renal disease worldwide. The treatment for IgAN remains challenging, and few randomized and controlled clinical trials have been conducted to evaluate new therapies. The present study assesses the efficacy and safety of Abelmoschus manihot (AM) in IgAN patients. STUDY DESIGN Randomized, non-inferiority, double-blind, double-dummy multicenter trial. SETTING AND PARTICIPANTS This trial was designed to recruit 1,600 biopsy-proven IgAN patients (proteinuria between 0.5-3.0 g/d and estimated glomerular filtration rate [eGFR] of ≥ 45 ml/min/1.73 m2) across China. INTERVENTIONS The participants were randomized at 1:1 to AM (2.5 g for three times per day) or losartan potassium (100 mg per day) for 48 weeks. OUTCOMES The primary outcome was the change in 24-hour proteinuria from baseline to week 48. The secondary outcomes were the change in eGFR from baseline to week 48, and the incidents of endpoint events (proteinuria ≥ 3.5 g/24 h, doubling of serum creatinine, or receiving renal replacement treatment). RESULTS Among 1,470 randomized patients (mean age, 37.4 [SD, 10.6] years old; 777 [52.9%] were female; mean eGFR, 95.0 [SD, 24.3] mL/min/1.73 m2; mean 24-hour proteinuria, 1.2 [SD, 0.7] g/d), the mean decline in 24-h proteinuria at week 48 was 230 mg and 253 mg in the AM and losartan potassium groups, respectively (P = 0.676). The mean difference in the change in 24-h proteinuria between these two groups was -23.32 mg (95% confident interval: -123.2 to 76.6, p = 0.647). The mean decline in eGFR was 0.41 ml/min/1.73 m2 and 0.76 ml/min/1.73 m2 in the AM and losartan potassium groups, respectively (p = 0.661). The mean difference in the change in eGFR between these two groups was -0.43 ml/min/1.73 m2 (95% confident interval: -1.99 to 1.13, p = 0.589). The incidence of endpoint events was 8.6% in the AM group and 8.2% in the losartan group (p = 0.851). LIMITATIONS The results of the trial may not be generalized to IgAN patients with a proteinuria of > 3.0 g/d and an eGFR of < 45 ml/min/1.73 m2. The long-term benefits of AM in reducing the risk of progressive renal dysfunction remains unclear, based on this 48-week observation. CONCLUSION AM can be recommended as a promising treatment for IgAN patients.
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Affiliation(s)
- Ping Li
- Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Chinese PLA General Hospital, Chinese PLA Medical School, Beijing 100853, China
| | - Hongli Lin
- Department of Nephrology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, China
| | - Zhaohui Ni
- Department of Nephrology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China
| | - Yongli Zhan
- Department of Nephrology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing 100053, China
| | - Yani He
- Department of Nephrology, Da Ping Hospital of Third Military Medical University, Chongqing, 400042, China
| | - Hongtao Yang
- Department of Nephrology, First Teaching Hospital of Tianjin University of TCM, Tianjin 300192, China
| | - Jingai Fang
- Department of Nephrology, The First Hospital of Shanxi Medical University, Taiyuan 030024, China
| | - Niansong Wang
- Department of Nephrology, The Six Affiliated Hospital of Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Wenge Li
- Department of Nephrology, China-Japan Friendship Hospital, Beijing 100029, China
| | - Guangyan Cai
- Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Chinese PLA General Hospital, Chinese PLA Medical School, Beijing 100853, China
| | - Yizhi Chen
- Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Chinese PLA General Hospital, Chinese PLA Medical School, Beijing 100853, China
| | - Peiqing Zhang
- Department of Nephrology, Heilongjiang Provincial Academy of Traditional Chinese Medicine, Heilongjiang, 150036, China
| | - Xiaoqin Wang
- Department of Nephrology, Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan, 430061, China
| | - Qinkai Chen
- Department of Nephrology, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, China
| | - Zhenjiang Li
- Department of Nephrology, Shanxi Provincial People's Hospital, Xi'an, 710068, China
| | - Xuefeng Sun
- Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Chinese PLA General Hospital, Chinese PLA Medical School, Beijing 100853, China.
| | - Xiangmei Chen
- Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Chinese PLA General Hospital, Chinese PLA Medical School, Beijing 100853, China.
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Predictive value of mesangial C3 and C4d deposition in IgA nephropathy. Clin Immunol 2019; 211:108331. [PMID: 31899330 DOI: 10.1016/j.clim.2019.108331] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 12/24/2019] [Accepted: 12/30/2019] [Indexed: 12/22/2022]
Abstract
We aimed to determine the relative contribution of each complement (C3 and C4d) deposition to the progression of IgA nephropathy (IgAN). We enrolled a total of 380 patients with biopsy-confirmed IgAN. Mesangial deposition of C3(<2+ vs. ≥2+) and C4d(positive vs. negative) was evaluated by immunofluorescence staining and immunohistochemistry, respectively. Study endpoint was the composite of a 30% decline in eGFR or ESRD. The risk of reaching the primary outcome was significantly higher in patients having C3 ≥ 2+ and C4d(+) than in corresponding counterparts. Adding C3 deposition to clinical data acquired at kidney biopsy modestly increased the area under the receiver-operating characteristic curve, net reclassification improvement, and integrated discrimination improvement (IDI); adding C4d increased IDI only. In conclusion, mesangial C3 and C4d deposition was an independent risk factor for progression of IgAN. C3 showed better predictability than C4d, suggesting that lectin pathway alone has limited clinical prognostic value.
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Wang L, Ren D, Huang T, Liu X, Xu G. The effectiveness and safety of full-dose versus half-dose corticosteroid plus renin-angiotensin system blockers for IgA nephropathy. Ther Adv Chronic Dis 2019; 10:2040622319887875. [PMID: 31762966 PMCID: PMC6854762 DOI: 10.1177/2040622319887875] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 09/10/2019] [Indexed: 01/28/2023] Open
Abstract
Background: Observational studies suggest that patients with immunoglobulin A nephropathy (IgAN) showed good responses to corticosteroids (CS) but experienced severe adverse effects. The authors conducted a cohort study to evaluate the effectiveness and safety of half-dose CS plus renin-angiotensin system blockers (RASB) (CS + RASB) versus full-dose CS in IgAN patients. Methods: A total of 162 kidney biopsy-confirmed IgAN patients with protein excretion levels ⩾0.75 g/d and an estimated glomerular filtration rate (eGFR) >30 ml/min/1.73 m2 were included. A total of 89 patients received half-dose CS + RASB (half CS + RASB), and 73 patients received full-dose CS (full CS). The primary outcomes were the complete remission rates and incidence of adverse events (AEs). The secondary outcomes included 24 h urinary protein (UP) levels and a combined event. Results: Over the 18 months follow-up, the complete remission rates were 59% (53/89 patients) and 57% (42/73 patients) in the half CS + RASB and full CS groups (p = 0.88), respectively. A total of five patients suffered from serious AEs (SAEs) in the full CS group during the observation period, and no SAEs were observed in the half CS + RASB group (p = 0.012). The incidences of total AEs (p = 0.003) and infections (p = 0.01) were lower in the half CS + RASB group than in the full CS group. Conclusions: Although half CS + RASB versus full CS did not differ in terms of reducing proteinuria, therapy with half CS + RASB resulted in fewer AEs in the IgAN patients.
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Affiliation(s)
- Li Wang
- Department of Nephrology, The Second Affiliated Hospital of Nanchang University, Donghu District, Nanchang, P.R. China
| | - Daijin Ren
- Department of Nephrology, The Second Affiliated Hospital of Nanchang University, Donghu District, Nanchang, P.R. China
| | - Tianlun Huang
- Department of Nephrology, The Second Affiliated Hospital of Nanchang University, Donghu District, Nanchang, P.R. China
| | - Xin Liu
- Department of Nephrology, The Second Affiliated Hospital of Nanchang University, Donghu District, Nanchang, P.R. China
| | - Gaosi Xu
- Department of Nephrology, The Second Affiliated Hospital of Nanchang University, No. 1, Minde Road, Donghu District, Nanchang 330006, P.R. China
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Abstract
Glomerulonephritis (GN) refers to a group of renal diseases affecting the glomeruli due to the damage mediated by immunological mechanisms. A large proportion of the disease manifestations are caused by disturbances in the complement system. They can be due to genetic errors, autoimmunity, microbes or abnormal immunoglobulins, like modified IgA or paraproteins. The common denominator in most of the problems is an overactive or misdirected alternative pathway complement activation. An assessment of kidney function, amount of proteinuria and hematuria are crucial elements to evaluate, when glomerulonephritis is suspected. However, the cornerstones of the diagnoses are renal biopsy and careful examination of the complement abnormality. Differential diagnostics between the various forms of GN is not possible based on clinical features, as they may vary greatly. This review describes the known mechanisms of complement dysfunction leading to different forms of primary GN (like IgA glomerulonephritis, dense deposit disease, C3 glomerulonephritis, post-infectious GN, membranous GN) and differences to atypical hemolytic uremic syndrome. It also covers the basic elements of etiology-directed therapy and prognosis of the most common forms of GN. Common principles in the management of GN include treatment of hypertension and reduction of proteinuria, some require immunomodulating treatment. Complement inhibition is an emerging treatment option. A thorough understanding of the basic disease mechanism and a careful follow-up are needed for optimal therapy.
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Affiliation(s)
- Kati Kaartinen
- Department of Nephrology, Abdominal Center, Helsinki University Central Hospital, Helsinki, Finland
| | - Adrian Safa
- Department of Biomedical Sciences, Humanitas University, Milan, Italy; Department of Bacteriology and Immunology, Translational Immunology Research Program, University of Helsinki, Helsinki, Finland
| | - Soumya Kotha
- Department of Biomedical Sciences, Humanitas University, Milan, Italy; Department of Bacteriology and Immunology, Translational Immunology Research Program, University of Helsinki, Helsinki, Finland
| | - Giorgio Ratti
- Department of Biomedical Sciences, Humanitas University, Milan, Italy; Department of Bacteriology and Immunology, Translational Immunology Research Program, University of Helsinki, Helsinki, Finland
| | - Seppo Meri
- Department of Biomedical Sciences, Humanitas University, Milan, Italy; Department of Bacteriology and Immunology, Translational Immunology Research Program, University of Helsinki, Helsinki, Finland; HUSLAB, Helsinki University Central Hospital, Helsinki, Finland.
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Abstract
Objective This study was performed to investigate the possible nephroprotective effects of losartan in a rat model of experimental IgA nephropathy (IgAN). Methods Thirty male Sprague–Dawley rats were randomly divided into three groups. The rats in the model group were treated with bovine serum albumin (oral gavage), lipopolysaccharide (tail vein injection), and carbon tetrachloride (subcutaneous injection); rats in the losartan group received treatments similar to those of the model group, and were orally gavaged with losartan; and rats in the control group received phosphate-buffered saline alone (both orally and intravenously). Results Losartan treatment lowered the 24-hour urinary protein, serum blood urea nitrogen, and serum creatinine levels. Proliferating mesangial cells with a variable increase in the mesangial matrix were detected in the model group, whereas injury in the losartan group was significantly attenuated. Immunohistochemistry revealed that the expression levels of transforming growth factor (TGF)-β1 and α-smooth muscle actin were significantly elevated in the model group but reduced in the losartan group. The expression levels of TGF-β1 and monocyte chemoattractant protein-1 were minimal in the control group, significantly increased in the model group, and reduced in the losartan group. Conclusion Losartan has a protective effect against tubulointerstitial injury in IgAN.
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Affiliation(s)
- Li Xing
- Department of Nephrology, First Affiliated Hospital of Harbin Medical University, Harbin, P. R. China
| | - Er Lin Song
- Department of Urinary Surgery, First Affiliated Hospital of Harbin Medical University, Harbin, P. R. China
| | - Xi Bei Jia
- Department of Nephrology, First Affiliated Hospital of Harbin Medical University, Harbin, P. R. China
| | - Jing Ma
- Department of Nephrology, First Affiliated Hospital of Harbin Medical University, Harbin, P. R. China
| | - Bing Li
- Department of Nephrology, Second Affiliated Hospital of Harbin Medical University, Harbin, P. R. China
| | - Xu Gao
- Department of Biochemistry and Molecular Biology of Harbin Medical University, Harbin, P. R. China
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Complement Activation in Progression of Chronic Kidney Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1165:423-441. [PMID: 31399977 DOI: 10.1007/978-981-13-8871-2_20] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Chronic kidney disease (CKD) is a public health problem worldwide, with increasing incidence and prevalence. The mechanisms underlying the progression to end-stage renal disease (ESRD) is not fully understood. The complement system was traditionally regarded as an important part of innate immunity required for host protection against infection and for maintaining host hemostasis. However, compelling evidence from both clinical and experimental studies has strongly incriminated complement activation as a pivotal pathogenic mediator of the development of multiple renal diseases and progressive replacement of functioning nephrons by fibrosis. Both anaphylatoxins, i.e., C3a and C5a, and membrane attack complex (MAC) contribute to the damage that occurs during chronic renal progression through various mechanisms including direct proinflammatory and fibrogenic activity, chemotactic effect, activation of the renal renin-angiotensin system, and enhancement of T-cell immunity. Evolving understanding of the mechanisms of complement-mediated renal injury has led to the emergence of complement-targeting therapeutics. A variety of specific antibodies and inhibitors targeting complement components have shown efficacy in reducing disease in animal models. Moreover, building on these advances, targeting complement has gained encouraging success in treating patients with renal diseases such as atypical hemolytic uremic syndrome (aHUS). Nevertheless, it still requires a great deal of effort to develop inhibitors that can be applied to treat more patients effectively in routine clinical practice.
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Obrișcă B, Ștefan G, Gherghiceanu M, Mandache E, Ismail G, Stancu S, Boitan B, Ion O, Mircescu G. "Associated" or "Secondary" IgA nephropathy? An outcome analysis. PLoS One 2019; 14:e0221014. [PMID: 31398224 PMCID: PMC6688810 DOI: 10.1371/journal.pone.0221014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 07/30/2019] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Whether differences in outcome between primary (pIgAN) and secondary IgA nephropathy (sIgAN) exist is uncertain. METHODS We conducted a retrospective, observational study that included all histologically diagnosed IgAN patients between 2010-2017 (N = 306), 248 with pIgAN and 58 with sIgAN. To obtain samples with similar risk of progression, sIgAN patients were grouped as liver disease and autoimmune/viral disease and propensity score matched to corresponding pIgAN samples. Univariate (Kaplan Meier) and multivariate time-dependent (Cox modelling) analyses were performed to identify predictors of the composite end-point (doubling of serum creatinine, end-stage kidney disease or death). RESULTS Of the whole cohort, 20% had sIgAN (6% alcoholic cirrhosis, 6% autoimmune disease and 8% viral infections). sIgAN patients were older, had more comorbidities, lower proteinuria and higher haematuria, but similar distribution in MESTC lesions and eGFR as those with pIgAN. They reached the end-point in similar proportions with those with pIgAN (43 vs. 30%; p = 0.09) but their mortality was higher (19 vs. 3%; p<0.0001). Both in unmatched (HR 0.80, 95%CI 0.42-1.52; p = 0.5) and matched samples (log-rank test: liver disease-IgAN vs. pIgAN, p = 0.1; autoimmune/viral-IgAN vs. pIgAN, p = 0.3), sIgAN was not predictive for end-point. In analyses restricted only to sIgAN, those with viral infections (HR, 10.98; 95% CI, 1.12-107.41; p = 0.03) and lower eGFR (HR, 0.94; 95%CI, 0.89-0.98; p = 0.007) had a worse prognosis. Immunosuppression did not influence outcome. CONCLUSIONS The differences in MESTC score and outcome between pIgAN and sIgAN seems to be minimal, suggesting that "associated" describes better than "secondary" the relationship among the two. Immunosuppression did not to influence outcome of sIgAN.
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Affiliation(s)
- Bogdan Obrișcă
- Nephrology Department, Fundeni Clinical Institute, Bucharest, Romania
- Nephrology Department,”Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - Gabriel Ștefan
- Nephrology Department,”Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
- ”Dr. Carol Davila” Teaching Hospital of Nephrology, Bucharest, Romania
| | - Mihaela Gherghiceanu
- Nephrology Department,”Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
- ”Victor Babes” National Institute of Pathology, Bucharest, Romania
| | - Eugen Mandache
- ”Dr. Carol Davila” Teaching Hospital of Nephrology, Bucharest, Romania
| | - Gener Ismail
- Nephrology Department, Fundeni Clinical Institute, Bucharest, Romania
- Nephrology Department,”Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
| | - Simona Stancu
- Nephrology Department,”Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
- ”Dr. Carol Davila” Teaching Hospital of Nephrology, Bucharest, Romania
| | - Bianca Boitan
- ”Dr. Carol Davila” Teaching Hospital of Nephrology, Bucharest, Romania
| | - Oana Ion
- Nephrology Department, Fundeni Clinical Institute, Bucharest, Romania
| | - Gabriel Mircescu
- Nephrology Department,”Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania
- ”Dr. Carol Davila” Teaching Hospital of Nephrology, Bucharest, Romania
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Gong WY, Liu M, Luo D, Liu FN, Yin LH, Li YQ, Zhang J, Peng H. High serum IgA/C3 ratio better predicts a diagnosis of IgA nephropathy among primary glomerular nephropathy patients with proteinuria ≤ 1 g/d: an observational cross-sectional study. BMC Nephrol 2019; 20:150. [PMID: 31039758 PMCID: PMC6492345 DOI: 10.1186/s12882-019-1331-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 04/08/2019] [Indexed: 11/22/2022] Open
Abstract
Background The serum immunoglobulin A (IgA)/C3 ratio is considered to be an effective predictor of IgA nephropathy (IgAN). This study sought to explore the diagnostic value of the IgA/C3 ratio in IgAN among primary glomerular nephropathy patients in China. Methods We recruited 1095 biopsy-diagnosed primary glomerular nephropathy patients, including 757 IgAN patients and 338 non-IgAN patients. Patient demographics, serum immunological indices, and other clinical examinations were measured. IgAN cases were propensity score matched (PSM) to non-IgAN cases on the logit of the propensity score using nearest neighbor matching in a 1:1 fashion, with a caliper of 0.02 with no replacements, according to age, gender, BMI, proteinuria level, and estimated glomerular filtration rate (eGFR). Results We found that in both the full cohort and PSM cohort, the IgA/C3 ratio in the IgAN group was significantly higher than that of the non-IgAN group. The same results were also obtained with stratification by different levels of proteinuria and renal function. In the PSM cohort, there was no difference in IgA/C3 ratio in patients with IgAN between different proteinuria groups and different chronic kidney disease (CKD) groups. The area under the ROC curve (AUROC) of the IgA/C3 ratio in distinguishing IgAN among primary glomerular disease was 0.767 in the full cohort, and 0.734 in the PSM cohort. The highest AUROC of the IgA/C3 ratio was in the ≤1 g/d proteinuria group (0.801 in the full cohort, and 0.803 in the PSM cohort); however, there was no difference between all CKD groups. Meanwhile, the diagnostic accordance rate for the diagnosis of IgAN among all patients with an IgA/C3 ratio > 3.5304 was as high as 92.02% in the full cohort. IgAN was independently correlated with IgA/C3 ratio in the full cohort by multivariate logistic regression analysis. Conclusions The present study provides clear evidence that the IgA/C3 ratio is an effective predictor of IgA diagnosis, especially in patients with proteinuria ≤1 g/d. In order to study the effectiveness of this biomarker, and to determine a standardized cut-off value, additional multicenter large-scale studies are needed. Electronic supplementary material The online version of this article (10.1186/s12882-019-1331-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wen-Yu Gong
- Division of Nephrology, Department of medicine, the First Affiliated Hospital, Jinan University, Guangzhou, 510630, Guangdong, China
| | - Man Liu
- Division of Gastroenterology and Hepatology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Dan Luo
- Division of Nephrology, Department of medicine, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, Guangdong, China
| | - Fan-Na Liu
- Division of Nephrology, Department of medicine, the First Affiliated Hospital, Jinan University, Guangzhou, 510630, Guangdong, China
| | - Liang-Hong Yin
- Division of Nephrology, Department of medicine, the First Affiliated Hospital, Jinan University, Guangzhou, 510630, Guangdong, China
| | - Yuan-Qing Li
- Division of Nephrology, Department of medicine, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, Guangdong, China
| | - Jun Zhang
- Division of Nephrology, Department of medicine, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, Guangdong, China.
| | - Hui Peng
- Division of Nephrology, Department of medicine, Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, 510630, Guangdong, China.
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Wen L, Zhao Z, Wang Z, Xiao J, Birn H, Gregersen JW. High levels of urinary complement proteins are associated with chronic renal damage and proximal tubule dysfunction in immunoglobulin A nephropathy. Nephrology (Carlton) 2019; 24:703-710. [PMID: 30141239 DOI: 10.1111/nep.13477] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2018] [Indexed: 11/29/2022]
Abstract
AIM Complement activation is involved in the pathogenesis and progression of immunoglobulin A nephropathy (IgAN); however, the clinical implication of abnormal complement protein levels in serum and urine is not clear. To address this we analyzed the correlation between disease activity and complement proteins in serum and urine from IgAN patients, and compared to patients with other types of chronic kidney disease (CKD) as well as healthy controls. METHODS We included 85 Chinese patients with IgAN, 23 patients with non-proliferative CKD, and 20 healthy individuals. Patients were divided according to the Oxford classification of M0E0S0T0 (group 1, n = 20), M1E1S0-1 T0-1 (group 2, n = 25), M1E1S0-1 T2 or M0E0S1T1-2 (group 3, n = 40). Complement factor H (CFH), mannose-binding lectin and membrane attack complex in serum and urine were measured by enzyme-linked immunosorbent assay. RESULTS Urinary CFH, membrane attack complex and serum CFH were increased in both IgAN and CKD patients compared with healthy controls. The urinary excretion of CFH was the highest in IgAN patients with most tubulointerstitial damage (IgAN group 3). Urinary CFH and mannose-binding lectin levels were significantly higher in IgAN patients with crescents formation (C1-2) than in patients without (C0). Urinary complement protein excretion correlated negatively with estimated glomerular filtration rate, and positively with urinary retinol-binding protein and α1-microglobulin excretion indicating proximal tubule dysfunction. CONCLUSION Increased urinary excretion of complement proteins in IgAN is related to chronic injury and tubular dysfunction. This warrants caution using urinary complement proteins as markers of disease activity.
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Affiliation(s)
- Lu Wen
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Zhanzheng Zhao
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Zheng Wang
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jing Xiao
- Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Henrik Birn
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.,Department of Renal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Jon W Gregersen
- Department of Nephrology, Aalborg University Hospital, Aalborg, Denmark
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Ouyang Y, Zhu L, Shi M, Yu S, Jin Y, Wang Z, Ma J, Yang M, Zhang X, Pan X, Ren H, Wang W, Zhang H, Xie J, Chen N. A Rare Genetic Defect of MBL2 Increased the Risk for Progression of IgA Nephropathy. Front Immunol 2019; 10:537. [PMID: 30967869 PMCID: PMC6438956 DOI: 10.3389/fimmu.2019.00537] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 02/27/2019] [Indexed: 12/23/2022] Open
Abstract
The aim of this study was to investigate the association between lectin pathway-related genetic variations and progression in IgA nephropathy. Biopsy-proven IgAN patients with eGFR ≥15 ml/min/1.73 m2 at baseline and a minimum follow-up of 12-months were enrolled. A total of 1,007 patients and 121 healthy controls were enrolled from two Chinese renal centers. The discovery cohort consisted of 606 patients, and the validation cohort consisted of 401 patients. First, promoters, all exons and their boundary regions of MBL2 and FCN2 were sequenced in 50 patients, and then 37 variations were identified. Of these variations, 7 expression-associated variations were selected and genotyped in the whole discovery cohort. We found that rs1800450 in MBL2 and rs7851696 in FCN2 were associated with an increased risk for ESRD as well as serum MBL or L-ficolin levels. However, only rs1800450 was successively validated for its association with ESRD (HR, 15.91; 3.27-77.34; P = 0.001) in the fully adjusted model in the validation cohort. In addition, 2.7% of patients, and 2.5% of healthy controls carried rs1800450-AA. IgAN patients with rs1800450-AA lacked expression of MBL in both serum and renal tissue and had more severe tubulointerstitial damage. Furthermore, a combined effect of rs1800450-AA with a previously reported clinical risk score was observed in which patients with both a high clinical risk score (≥1%) and rs1800450-AA had a strikingly increased 10-years ESRD risk by 37.1-fold (7.17 to 192.13-fold). In summary, IgAN patients carrying MBL2 rs1800450-AA have a high risk for renal function deterioration, probably due to inactivation of the complement MBL pathway.
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Affiliation(s)
- Yan Ouyang
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Li Zhu
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China
| | - Manman Shi
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shuwen Yu
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yuanmeng Jin
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhaohui Wang
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jun Ma
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Meng Yang
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaoyan Zhang
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaoxia Pan
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hong Ren
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Weiming Wang
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hong Zhang
- Renal Division, Department of Medicine, Peking University First Hospital, Beijing, China
| | - Jingyuan Xie
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Nan Chen
- Department of Nephrology, Institute of Nephrology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Rizk DV, Maillard N, Julian BA, Knoppova B, Green TJ, Novak J, Wyatt RJ. The Emerging Role of Complement Proteins as a Target for Therapy of IgA Nephropathy. Front Immunol 2019; 10:504. [PMID: 30941137 PMCID: PMC6433978 DOI: 10.3389/fimmu.2019.00504] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 02/25/2019] [Indexed: 12/28/2022] Open
Abstract
IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis worldwide and a common cause of end-stage renal disease. Evaluation of a kidney biopsy is necessary for diagnosis, with routine immunofluorescence microscopy revealing dominant or co-dominant IgA immunodeposits usually with complement C3 and sometimes IgG and/or IgM. IgA nephropathy reduces life expectancy by more than 10 years and leads to kidney failure in 20–40% of patients within 20 years of diagnosis. There is accumulating clinical, genetic, and biochemical evidence that complement plays an important role in the pathogenesis of IgA nephropathy. The presence of C3 differentiates the diagnosis of IgA nephropathy from the subclinical deposition of glomerular IgA. Markers for the activation of the alternative and mannan-binding lectin (MBL) pathways in renal-biopsy specimens are associated with disease activity and portend a worse renal outcome. Complement proteins in the circulation have also been evaluated in IgA nephropathy and found to be of prognostic value. Recently, genetic studies have identified IgA nephropathy-associated loci. Within these loci are genes encoding products involved in complement regulation and interaction with immune complexes. Put together, these data identify the complement cascade as a rational treatment target for this chronic kidney disease. Recent case reports on the successful use of humanized anti-C5 monoclonal antibody eculizumab are consistent with this hypothesis, but a better understanding of the role of complement in IgA nephropathy is needed to guide future therapeutic interventions.
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Affiliation(s)
- Dana V Rizk
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Nicolas Maillard
- Department of Nephrology, Dialysis, Transplantation, CHU de Saint-Etienne, GIMAP, EA3064, Université Jean Monnet, COMUE Université de Lyon, Rhône-Alpes, France
| | - Bruce A Julian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Barbora Knoppova
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States.,Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czechia
| | - Todd J Green
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Robert J Wyatt
- Department of Pediatrics, University of Tennessee Health Sciences Center, Memphis, TN, United States
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Okonogi H, Kawamura T, Joh K, Koike K, Miyazaki Y, Ogura M, Tsuboi N, Hirano K, Matsushima M, Yokoo T, Horikoshi S, Suzuki Y, Yasuda T, Shirai S, Shibata T, Hattori M, Akioka Y, Katafuchi R, Hashiguchi A, Hisano S, Shimizu A, Kimura K, Maruyama S, Matsuo S, Tomino Y. A grading system that predicts the risk of dialysis induction in IgA nephropathy patients based on the combination of the clinical and histological severity. Clin Exp Nephrol 2019; 23:16-25. [PMID: 30367317 PMCID: PMC6344391 DOI: 10.1007/s10157-018-1657-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 10/01/2018] [Indexed: 12/02/2022]
Abstract
Histological classification is essential in the clinical management of immunoglobulin A nephropathy (IgAN). However, there are limitations in predicting the prognosis of IgAN based on histological information alone, which suggests the need for better prognostic models. Therefore, we defined a prognostic model by combining the grade of clinical severity with the histological grading system by the following processes. We included 270 patients and explored the clinical variables associated with progression to end-stage renal disease (ESRD). Then, we created a predictive clinical grading system and defined the risk grades for dialysis induction by a combination of the clinical grade (CG) and the histological grade (HG). A logistic regression analysis revealed that the 24-h urinary protein excretion (UPE) and the estimated glomerular filtration rate (eGFR) were significant independent variables. We selected UPE of 0.5 g/day and eGFR of 60 ml/min/1.73 m2 as the threshold values for the classification of CG. The risk of progression to ESRD of patients with CG II and III was significantly higher than that of patients with CG I. The patients were then re-classified into nine compartments based on the combination of CG and HG. Furthermore, the nine compartments were grouped into four risk groups. The risk of ESRD in the moderate, high, and super-high-risk groups was significantly higher than that in the low-risk group. Herein, we are giving a detailed description of our grading system for IgA nephropathy that predicted the risk of dialysis based on the combination of CG and HG.
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Affiliation(s)
- Hideo Okonogi
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8, Nishi-Shimbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Tetsuya Kawamura
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8, Nishi-Shimbashi, Minato-ku, Tokyo, 105-8461, Japan.
| | - Kensuke Joh
- Department of Pathology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Kentaro Koike
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8, Nishi-Shimbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Yoichi Miyazaki
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8, Nishi-Shimbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Makoto Ogura
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8, Nishi-Shimbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Nobuo Tsuboi
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8, Nishi-Shimbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Keita Hirano
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8, Nishi-Shimbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Masato Matsushima
- Division of Clinical Epidemiology, General Research Center of Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Takashi Yokoo
- Division of Nephrology and Hypertension, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8, Nishi-Shimbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Satoshi Horikoshi
- Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, Juntendo University, Tokyo, Japan
| | - Yusuke Suzuki
- Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, Juntendo University, Tokyo, Japan
| | - Takashi Yasuda
- Department of Internal Medicine, Kichijoji Asahi Hospital, Tokyo, Japan
| | - Sayuri Shirai
- Division of Kidney and Hypertension, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Takanori Shibata
- Division of Nephrology, Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Motoshi Hattori
- Department of Pediatric Nephrology, Tokyo Women's Medical University School of Medicine, Tokyo, Japan
| | - Yuko Akioka
- Department of Pediatric Nephrology, Tokyo Women's Medical University School of Medicine, Tokyo, Japan
| | - Ritsuko Katafuchi
- Kidney Unit, National Fukuoka-Higashi Medical Center, Fukuoka, Japan
| | - Akinori Hashiguchi
- Department of Pathology, Keio University School of Medicine, Tokyo, Japan
| | - Satoshi Hisano
- Department of Pathology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Akira Shimizu
- Department of Analytic Human Pathology, Nippon Medical School, Tokyo, Japan
| | - Kenjiro Kimura
- Division of Kidney and Hypertension, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Shoichi Maruyama
- Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Nagoya, Nagoya, Japan
| | - Seiichi Matsuo
- Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, University of Nagoya, Nagoya, Japan
| | - Yasuhiko Tomino
- Division of Nephrology, Department of Internal Medicine, Faculty of Medicine, Juntendo University, Tokyo, Japan
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Renal miR-148b is associated with megalin down-regulation in IgA nephropathy. Biosci Rep 2018; 38:BSR20181578. [PMID: 30355654 PMCID: PMC6239259 DOI: 10.1042/bsr20181578] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/06/2018] [Accepted: 10/16/2018] [Indexed: 12/13/2022] Open
Abstract
Megalin is essential for proximal tubule reabsorption of filtered proteins, hormones, and vitamins, and its dysfunction has been reported in IgA nephropathy (IgAN). miR-148b has been shown to regulate renal megalin expression in vitro and in animal models of kidney disease. We examined a potential role of miR-148b and other miRNAs in regulating megalin expression in IgAN by analyzing the association between megalin and miR-148b, miR-21, miR-146a, and miR-192 expression. Quantitative PCR (qPCR) analysis identified a marked increase in renal levels of several miRNAs, including miR-148b, miR-21, miR-146a, and a significant decrease in megalin mRNA levels in IgAN patients when compared with normal controls. By multiple linear regression analysis, however, only renal miR-148b was independently associated with megalin mRNA levels in IgAN. Proximal tubule megalin expression was further evaluated by immunofluorescence labeling of biopsies from the patients. The megalin expression was significantly lower in patients with highest levels of renal miR-148b compared with patients with lowest levels. To examine the direct effects of the miRNAs on megalin and other membrane proteins expression, proximal tubule LLC-PK1 cells were transfected with miR-148b, miR-21, miR-146a, or miR-192 mimics. Transfection with miR-148b mimic, but not the other three miRNA mimics inhibited endogenous megalin mRNA expression. No significant effect of any of the four miRNA mimics was observed on cubilin or aquaporin 1 (AQP1) mRNA expression. The findings suggest that miR-148b negatively regulates megalin expression in IgAN, which may affect renal uptake and metabolism of essential substances.
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68
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Saha MK, Julian BA, Novak J, Rizk DV. Secondary IgA nephropathy. Kidney Int 2018; 94:674-681. [PMID: 29804660 PMCID: PMC6981247 DOI: 10.1016/j.kint.2018.02.030] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 01/24/2018] [Accepted: 02/06/2018] [Indexed: 12/14/2022]
Abstract
IgA nephropathy is the most common primary glomerulonephritis worldwide. Its frequent coexistence with inflammatory, infectious, or malignant processes raises the possibility of a pathologic rather than coincidental association. Major strides have been made to elucidate the underlying pathophysiologic events that culminate in the development of primary IgA nephropathy. Whether secondary forms of the disease share common pathways triggered by underlying disorders or different mechanisms leading to similar pathologic findings remains to be determined. In this article we describe the most frequent etiologies for secondary IgA nephropathy and review the available literature for the pathophysiology.
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Affiliation(s)
- Manish K Saha
- Department of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA; Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Bruce A Julian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Dana V Rizk
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.
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69
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Alexander S, John GT, Korula A, Vijayakumar TS, David VG, Mohapatra A, Valson AT, Jacob S, Koshy PM, Rajan G, John EE, Matthai SM, Jeyaseelan L, Ponnusamy B, Cook T, Pusey C, Daha MR, Feehally J, Barratt J, Varughese S. Protocol and rationale for the first South Asian 5-year prospective longitudinal observational cohort study and biomarker evaluation investigating the clinical course and risk profile of IgA nephropathy: GRACE IgANI cohort. Wellcome Open Res 2018; 3:91. [PMID: 30345379 PMCID: PMC6148466 DOI: 10.12688/wellcomeopenres.14644.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2018] [Indexed: 12/18/2022] Open
Abstract
Background: IgA nephropathy (IgAN) is the most common primary glomerulonephritis and an important cause of end-stage kidney disease. Unlike the slowly progressive course seen among Caucasian and East Asian subjects (actuarial survival 80-85% over 10 years), in India about 30-40% of patients have nephrotic syndrome and renal dysfunction at presentation and a 10-year renal survival of 35%, as reported from a retrospective registry. These observations cannot be entirely attributed to a lack of uniform screening protocols or late referral and attest to the probability that IgAN may not be the same disease in different parts of the world. Methods: We will prospectively recruit 200 patients with IgAN (the GRACE IgANI- Glomerular Research And Clinical Experiments- Ig A Nephropathy in Indians-cohort) and stratify them into low and high risk of progression based on published absolute renal risk scores. We will test the validity of this risk score in an unselected Indian IgAN population over a 5-year follow-up period. In parallel, we will undertake extensive exploratory serum, urine, renal and microbiome biomarker studies, firstly, to determine if the underlying pathogenic pathways are the same in Indian IgAN compared to those reported in Caucasian and East Asian IgAN. Secondly, we will systematically assess the value of measuring selected biomarkers and adding this data to traditional measures of risk in IgAN to predict kidney failure. We ultimately hope to generate a composite IgAN risk score specific for the Indian population. Ethics and data dissemination: Approval was obtained from the Institutional Review Board (Silver, Research and Ethics Committee) of the Christian Medical College, Vellore, India (Ref. No. IRB Min. No. 8962 [Other] dated 23.07.2014 and IRB Min. No. 9481 [Other] dated 24.06.2015). It is anticipated that results of this study will be presented at national and international meetings, with reports being published from late 2018.
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Affiliation(s)
- Suceena Alexander
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - George T John
- Department of Renal Medicine, Royal Brisbane and Women's Hospital, Queensland, 4029, Australia
| | - Anila Korula
- Department of General Pathology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - T S Vijayakumar
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Vinoi George David
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Anjali Mohapatra
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Anna T Valson
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Shibu Jacob
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Pradeep Mathew Koshy
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Gautam Rajan
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Elenjickal Elias John
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Smita Mary Matthai
- Central Electron Microscope Unit, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - L Jeyaseelan
- Department of Biostatistics, Christian Medical College, Vellore, Tamil Nadu, 632004, India
| | - Babu Ponnusamy
- Centre for Cellular and Molecular Platforms, Bengaluru, Karnataka, 560065, India
| | - Terence Cook
- Centre for Complement and Inflammation Research, Imperial College, London, UK
| | - Charles Pusey
- Department of Medicine, Imperial College Healthcare NHS Trust, London, UK
| | - Mohamed R Daha
- Rijksuniversiteit Groningen Faculteit Biologie, Groningen, Netherlands
| | - John Feehally
- University of Leicester, College of Medicine Biological Sciences and Psychology, Leicester, UK
| | - Jonathan Barratt
- University of Leicester, College of Medicine Biological Sciences and Psychology, Leicester, UK
| | - Santosh Varughese
- Department of Nephrology, Christian Medical College, Vellore, Tamil Nadu, 632004, India
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Lee K, Shin J, Park J, Hwang S, Jang HR, Huh W, Kwon GY, Kim YG, Oh HY, Lee JE, Kim DJ. First-year GFR slope and long-term renal outcome in IgA nephropathy. Eur J Clin Invest 2018; 48:e12936. [PMID: 29660832 DOI: 10.1111/eci.12936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 04/09/2018] [Indexed: 12/20/2022]
Abstract
BACKGROUND IgA nephropathy (IgAN) is the most frequent primary glomerular disease and the leading cause of end-stage renal disease. We investigated clinicopathologic predictors of renal survival in patients with IgAN with a focus on glomerular filtration rate (GFR) decline slope. MATERIALS AND METHODS We screened all patients with primary IgAN between 1995 and 2012. Renal progression was defined as doubling of serum creatinine. Using serial serum creatinine levels during the first-year, we calculated the GFR decline slopes. Further, we defined patients in the steepest GFR slope quartile as rapid decliners and those in the second steepest GFR slope quartile as slow decliners. Others were defined as nondecliners. RESULTS Of 214 participants, baseline GFR was 81 (62, 100) mL/min/1.73 m2 , which was not different among the 3 groups. Rapid decliners and slow decliners had higher levels of urinary protein/creatinine ratio (0.88, 0.89 and 0.58 g/gCr, respectively, P < .001). Five-year renal survival was 76% in rapid decliners, 91% in slow decliners and 100% in nondecliners (P < .001, rapid or slow decliners vs nondecliners). After adjustment for clinicopathologic variables, slow decliners were associated with an 8.8-fold higher risk of progression (P = .011), and rapid decliners were associated with a 10.2-fold increased risk of progression (P = .007) compared with nondecliners. CONCLUSIONS First-year GFR slope was associated with increased risk of renal progression, independent of proteinuria and histologic findings. Further studies are needed to investigate whether early GFR change can identify high-risk patients who benefit from immunosuppressive treatment in IgAN.
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Affiliation(s)
- Kyungho Lee
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jungho Shin
- Division of Nephrology, Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea
| | - Jeeeun Park
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Subin Hwang
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Hye Ryoun Jang
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Wooseong Huh
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ghee Young Kwon
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yoon-Goo Kim
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ha Young Oh
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jung Eun Lee
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Dae Joong Kim
- Division of Nephrology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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71
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Di Vico MC, Messina M, Fop F, Barreca A, Segoloni GP, Biancone L. Recurrent IgA nephropathy after renal transplantation and steroid withdrawal. Clin Transplant 2018; 32:e13207. [PMID: 29345747 DOI: 10.1111/ctr.13207] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2018] [Indexed: 01/19/2023]
Abstract
Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis; the reported recurrence rate of IgAN after renal transplantation is as high as 13%-50%. The impact of immunosuppressive therapy and steroid withdrawal on the risk of recurrence of IgAN is still under debate. We performed a retrospective single-center study, selecting 123 kidney transplants (rtx) in 120 patients, between January 1995 and December 2012, with IgAN on the native kidney. In 51 of 123 transplants, at least one post-transplantation biopsy for clinical indication was performed; in 28 of 51 transplants, IgAN recurrence (IgANr) was demonstrated. This group (G1; N = 28) was compared with a group without IgANr (G2; N = 23). In our study, clinically evident IgANr rate was 54.9% (28/51) on biopsied patients. At discharge, the use of the immunosuppressant drugs (tacrolimus, cyclosporine A, mycophenolate mofetil, azathioprine, mTor inhibitors) was not associated with an increased risk of IgANr (P = NS). At discharge, all patients were steroid treated. Neither the use of tacrolimus, mycophenolate mofetil, nor mTor inhibitors (mTori) at biopsy time were associated with IgANr. However, IgANr was significantly higher in patients who experienced steroid withdrawal at any post-transplantation time (OR 7.7 P = .03). The median time to recurrence after steroid withdrawal was 59 months (min 4.18, max 113.2).
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Affiliation(s)
- Maria Cristina Di Vico
- Department of Medical Sciences, Renal Transplantation Unit 'A. Vercellone', Division of Nephrology Dialysis and Transplantation, Città della Salute e della Scienza Hospital, University of Turin, Turin, Italy
| | - Maria Messina
- Department of Medical Sciences, Renal Transplantation Unit 'A. Vercellone', Division of Nephrology Dialysis and Transplantation, Città della Salute e della Scienza Hospital, University of Turin, Turin, Italy
| | - Fabrizio Fop
- Department of Medical Sciences, Renal Transplantation Unit 'A. Vercellone', Division of Nephrology Dialysis and Transplantation, Città della Salute e della Scienza Hospital, University of Turin, Turin, Italy
| | - Antonella Barreca
- Division of Pathology, Department of Medical Sciences, Città della Salute e della Scienza Hospital, University of Turin, Turin, Italy
| | - Giuseppe Paolo Segoloni
- Department of Medical Sciences, Renal Transplantation Unit 'A. Vercellone', Division of Nephrology Dialysis and Transplantation, Città della Salute e della Scienza Hospital, University of Turin, Turin, Italy
| | - Luigi Biancone
- Department of Medical Sciences, Renal Transplantation Unit 'A. Vercellone', Division of Nephrology Dialysis and Transplantation, Città della Salute e della Scienza Hospital, University of Turin, Turin, Italy
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72
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Jullien P, Laurent B, Claisse G, Masson I, Dinic M, Thibaudin D, Berthoux F, Alamartine E, Mariat C, Maillard N. Deletion Variants of CFHR1 and CFHR3 Associate with Mesangial Immune Deposits but Not with Progression of IgA Nephropathy. J Am Soc Nephrol 2017; 29:661-669. [PMID: 29114042 DOI: 10.1681/asn.2017010019] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 10/08/2017] [Indexed: 11/03/2022] Open
Abstract
Activation of complement through the alternative pathway has a key role in the pathogenesis of IgA nephropathy (IgAN). Large, international, genome-wide association studies have shown that deletion of complement factor H-related genes 1 and 3 (CFHR3,1Δ) is associated with a reduced risk of developing IgAN, although the prognostic value of these deletions in IgAN remains unknown. Here, we compared the renal outcomes of patients with IgAN according to their CFHR3,1Δ genotype. This retrospective, monocentric cohort study included 639 white patients with biopsy-proven IgAN since 1979 (mean age at diagnosis, 40.1 years; median follow-up, 132 months). We determined the number of CFHR3 and CFHR1 gene copies by quantitative PCR and collected clinical and biologic data by reviewing the patients' medical records. In all, 30.5% of the patients were heterozygous and 4% were homozygous for CFHR3,1Δ We did not detect an association between CFHR3,1Δ and age, eGFR, urinary protein excretion rate, or the presence of hypertension or hematuria at the time of diagnosis. The mean intensities of immune IgA, IgG, and C3 deposits were lower in the group with heterozygous or homozygous gene deletions than in those with no deletion. However, CFHR3,1Δ did not associate with progression to stage 3 CKD or renal death. In conclusion, the CFHR3,1Δ genotype did not associate with progression toward CKD stages 3 and 5 in our white population of patients with IgAN, although it did associate with a reduced level of glomerular immune deposits.
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Affiliation(s)
- Perrine Jullien
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and.,Groupe Immunité des Muqueuses et Agents Pathogènes Laboratory, Equipe d'Accueil 3064, Jean Monnet University, Saint-Etienne, Communauté d'Universités et Établissements de Lyon, France
| | - Blandine Laurent
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and
| | - Guillaume Claisse
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and
| | - Ingrid Masson
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and
| | - Miriana Dinic
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and
| | - Damien Thibaudin
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and
| | - Francois Berthoux
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and
| | - Eric Alamartine
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and
| | - Christophe Mariat
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and.,Groupe Immunité des Muqueuses et Agents Pathogènes Laboratory, Equipe d'Accueil 3064, Jean Monnet University, Saint-Etienne, Communauté d'Universités et Établissements de Lyon, France
| | - Nicolas Maillard
- Department of Nephrology, Dialysis and Renal Transplantation, University North Hospital, Saint-Etienne, France; and .,Groupe Immunité des Muqueuses et Agents Pathogènes Laboratory, Equipe d'Accueil 3064, Jean Monnet University, Saint-Etienne, Communauté d'Universités et Établissements de Lyon, France
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Kee YK, Yoon CY, Kim SJ, Moon SJ, Kim CH, Park JT, Lim BJ, Chang TI, Kang EW, Kie JH, Yoo TH, Jeong HJ, Kang SW, Han SH. Determination of the optimal target level of proteinuria in the management of patients with glomerular diseases by using different definitions of proteinuria. Medicine (Baltimore) 2017; 96:e8154. [PMID: 29095250 PMCID: PMC5682769 DOI: 10.1097/md.0000000000008154] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Proteinuria is a major determinant of adverse renal outcome, and its reduction slows renal progression in glomerular diseases. However, the optimal target of proteinuria in glomerular diseases is unclear, and discrepancies in the definition of proteinuria produce ambiguous findings. Here we investigated the optimal target of proteinuria by using different definitions of proteinuria. We analyzed 574 IgA nephropathy (IgAN), 175 membranous nephropathy (MGN), and 177 focal segmental glomerulosclerosis (FSGS) cases from 3 Korean kidney centers. We evaluated the impact of proteinuria on renal outcome with 2 definitions: time-average proteinuria (TAP) and time-varying proteinuria (TVP). The endpoint was renal progression, defined as a 50% decline in glomerular filtration rate or end-stage renal disease. During a median follow-up of 57.3 months, the primary outcome occurred in 54 patients with IgAN, 26 with MGN, and 30 with FSGS. Multivariate Cox regression using TAP indicated that there was a linear association between proteinuria and risk of renal progression in IgAN. However, moderate proteinuria was not associated with an increased risk of renal progression in MGN and FSGS. In contrast, the analysis by TVP showed that the risk significantly increased in proportion to proteinuria during follow-up in all 3 diseases. Our findings suggest that TVP-based model can delineate association between proteinuria and risk of renal progression better than TAP-based model, considering that TVP reflects the dynamic change of proteinuria over time. Thus, proteinuria reduction to the lowest possible level is required to improve renal outcomes in patients with glomerular diseases.
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Affiliation(s)
- Youn Kyung Kee
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University
| | - Chan-Yun Yoon
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University
| | - Seung Jun Kim
- Department of Internal Medicine, International St. Mary's Hospital, Catholic Kwandong University
| | - Sung Jin Moon
- Department of Internal Medicine, International St. Mary's Hospital, Catholic Kwandong University
| | - Chan Ho Kim
- Department of Internal Medicine, International St. Mary's Hospital, Catholic Kwandong University
| | - Jung Tak Park
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University
| | - Beom Jin Lim
- Department of Pathology, College of Medicine, Institute of Kidney Disease Research, Yonsei University
| | - Tae Ik Chang
- Department of Internal Medicine, NHIS Medical Center, Ilsan Hospital, Seoul, South Korea
| | - Ea Wha Kang
- Department of Internal Medicine, NHIS Medical Center, Ilsan Hospital, Seoul, South Korea
| | - Jeong Hae Kie
- Department of Internal Medicine, NHIS Medical Center, Ilsan Hospital, Seoul, South Korea
| | - Tae-Hyun Yoo
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University
| | - Hyun Joo Jeong
- Department of Pathology, College of Medicine, Institute of Kidney Disease Research, Yonsei University
| | - Shin-Wook Kang
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University
| | - Seung Hyeok Han
- Department of Internal Medicine, College of Medicine, Institute of Kidney Disease Research, Yonsei University
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Hassan EA, Ali TZ, Abdulbaki A, Ibrahim IA, Almanae HM, Aleid HA. Histopathologic Findings of Potential Kidney Donors With Asymptomatic Microscopic Hematuria: Impact on Donation. Transplant Proc 2017; 49:1729-1732. [PMID: 28923616 DOI: 10.1016/j.transproceed.2017.05.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 05/13/2017] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Isolated microscopic hematuria (IMH) is not uncommon in potential kidney donors. AIM The aim was to study the kidney biopsy findings of potential kidney donors with IMH and the impact of the histopathologic diagnoses on the decision to accept or decline such donors from kidney donation. METHODS In this retrospective study, all the potential kidney donors with IMH were identified from the medical records of patients who underwent kidney biopsies between January 2010 and December 2016. RESULTS Forty-five such individuals were identified. The mean age of these potential donors was 32.6 years and 76% were male. All of them had normal blood pressure and no significant proteinuria. Seventeen (38%) biopsies showed histopathologic abnormalities; thin basement membrane disease (n = 13; 28%) was the most common cause followed by immunoglobulin (Ig)A nephropathy (n = 4; 9%). Donors with abnormal biopsy findings were excluded from donation. However, 62% of the potential donors had normal kidney biopsy findings and were accepted for kidney donation. CONCLUSION IMH justifies extensive work-up including kidney biopsy to identify donors who may have underlying significant glomerular pathology excluding them from kidney donation. On the other hand, kidney biopsy also helps in accepting the donors if it does not show significant abnormality.
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Affiliation(s)
- E A Hassan
- Adult Transplant Nephrology, Department of Kidney & Pancreas Transplantation, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia; Department of Nephrology, Fayoum University, Fayoum, Egypt.
| | - T Z Ali
- Adult Transplant Nephrology, Department of Kidney & Pancreas Transplantation, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - A Abdulbaki
- Adult Transplant Nephrology, Department of Kidney & Pancreas Transplantation, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - I A Ibrahim
- Adult Transplant Nephrology, Department of Kidney & Pancreas Transplantation, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia; Department of Nephrology, Cairo University, Cairo, Egypt
| | - H M Almanae
- Department of Pathology & Laboratory Medicine, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
| | - H A Aleid
- Adult Transplant Nephrology, Department of Kidney & Pancreas Transplantation, King Faisal Specialist Hospital & Research Centre, Riyadh, Kingdom of Saudi Arabia
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Zhang J, Ren P, Wang Y, Feng S, Wang C, Shen X, Weng C, Lang X, Chen Z, Jiang H, Chen J. Serum Matrix Metalloproteinase-7 Level is Associated with Fibrosis and Renal Survival in Patients with IgA Nephropathy. Kidney Blood Press Res 2017; 42:541-552. [DOI: 10.1159/000477132] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 03/08/2017] [Indexed: 11/19/2022] Open
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76
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Fellström BC, Barratt J, Cook H, Coppo R, Feehally J, de Fijter JW, Floege J, Hetzel G, Jardine AG, Locatelli F, Maes BD, Mercer A, Ortiz F, Praga M, Sørensen SS, Tesar V, Del Vecchio L. Targeted-release budesonide versus placebo in patients with IgA nephropathy (NEFIGAN): a double-blind, randomised, placebo-controlled phase 2b trial. Lancet 2017; 389:2117-2127. [PMID: 28363480 DOI: 10.1016/s0140-6736(17)30550-0] [Citation(s) in RCA: 229] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 11/21/2016] [Accepted: 12/09/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND IgA nephropathy is thought to be associated with mucosal immune system dysfunction, which manifests as renal IgA deposition that leads to impairment and end-stage renal disease in 20-40% of patients within 10-20 years. In this trial (NEFIGAN) we aimed to assess safety and efficacy of a novel targeted-release formulation of budesonide (TRF-budesonide), designed to deliver the drug to the distal ileum in patients with IgA nephropathy. METHODS We did a randomised, double-blind, placebo-controlled phase 2b trial, comprised of 6-month run-in, 9-month treatment, and 3-month follow-up phases at 62 nephrology clinics across ten European countries. We recruited patients aged at least 18 years with biopsy-confirmed primary IgA nephropathy and persistent proteinuria despite optimised renin-angiotensin system (RAS) blockade. We randomly allocated patients with a computer algorithm, with a fixed block size of three, in a 1:1:1 ratio to 16 mg/day TRF-budesonide, 8 mg/day TRF-budesonide, or placebo, stratified by baseline urine protein creatinine ratio (UPCR). Patients self-administered masked capsules, once daily, 1 h before breakfast during the treatment phase. All patients continued optimised RAS blockade treatment throughout the trial. Our primary outcome was mean change from baseline in UPCR for the 9-month treatment phase, which was assessed in the full analysis set, defined as all randomised patients who took at least one dose of trial medication and had at least one post-dose efficacy measurement. Safety was assessed in all patients who received the intervention. This trial is registered with ClinicalTrials.gov, number NCT01738035. FINDINGS Between Dec 11, 2012, and June 25, 2015, 150 randomised patients were treated (safety set) and 149 patients were eligible for the full analysis set. Overall, at 9 months TRF-budesonide (16 mg/day plus 8 mg/day) was associated with a 24·4% (SEM 7·7%) decrease from baseline in mean UPCR (change in UPCR vs placebo 0·74; 95% CI 0·59-0·94; p=0·0066). At 9 months, mean UPCR had decreased by 27·3% in 48 patients who received 16 mg/day (0·71; 0·53-0·94; p=0·0092) and 21·5% in the 51 patients who received 8 mg/day (0·76; 0·58-1·01; p=0·0290); 50 patients who received placebo had an increase in mean UPCR of 2·7%. The effect was sustained throughout followup. Incidence of adverse events was similar in all groups (43 [88%] of 49 in the TRF-budesonide 16 mg/day group, 48 [94%] of 51 in the TRF-budesonide 8 mg/day, and 42 [84%] of 50 controls). Two of 13 serious adverse events were possibly associated with TRF-budesonide-deep vein thrombosis (16 mg/day) and unexplained deterioration in renal function in follow-up (patients were tapered from 16 mg/day to 8 mg/day over 2 weeks and follow-up was assessed 4 weeks later). INTERPRETATION TRF-budesonide 16 mg/day, added to optimised RAS blockade, reduced proteinuria in patients with IgA nephropathy. This effect is indicative of a reduced risk of future progression to end-stage renal disease. TRF-budesonide could become the first specific treatment for IgA nephropathy targeting intestinal mucosal immunity upstream of disease manifestation. FUNDING Pharmalink AB.
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Affiliation(s)
| | | | | | - Rosanna Coppo
- Fondazione Ricerca Molinette, Regina Margherita Hospital, Turin, Italy
| | | | | | | | - Gerd Hetzel
- HeinrichHeine-University, DaVita Renal Center, Düsseldorf, Germany
| | | | | | | | | | | | - Manuel Praga
- Complutense University, Investigation Institute Hospital 12 de Octubre, Madrid, Spain
| | - Søren S Sørensen
- Rigshospitalet-Copenhagen University Hospital, Copenhagen, Denmark
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Zhang Y, Yan X, Zhao T, Xu Q, Peng Q, Hu R, Quan S, Zhou Y, Xing G. Targeting C3a/C5a receptors inhibits human mesangial cell proliferation and alleviates immunoglobulin A nephropathy in mice. Clin Exp Immunol 2017; 189:60-70. [PMID: 28295247 DOI: 10.1111/cei.12961] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/28/2017] [Indexed: 11/27/2022] Open
Abstract
Complement activation has a deep pathogenic influence in immunoglobulin (Ig)A nephropathy (IgAN). C3a and C5a, small cleavage fragments generated by complement activation, are key mediators of inflammation. The fragments exert broad proinflammatory effects by binding to specific receptors (C3aR and C5aR, respectively). However, no studies thus far have investigated the effects of C3a, C5a and their receptors on IgAN. We observed that C3aR and C5aR antagonists repressed IgA-induced cell proliferation and interleukin (IL)-6 and monocyte chemotactic protein 1 (MCP-1) production in cultured human mesangial cells (HMCs). Furthermore, an IgAN mouse model induced by Sendai virus infection was employed to investigate the effects of C3aR and C5aR on IgAN in vivo for the first time. Wild-type (WT) and several knock-out mouse strains (C3aR-/- or C5aR-/- ) were immunized intranasally with increasing doses of inactivated virus for 14 weeks and were subjected to two intravenous viral challenges during the time-period indicated. In the Sendai virus-induced IgAN model, C3aR/C5aR-deficient mice had significantly reduced proteinuria, lower renal IgA and C3 deposition, less histological damage and reduced mesangial proliferation compared with WT mice. Both C3aR deficiency and C5aR deficiency, especially C3aR deficiency, inhibited renal tumour necrosis factor (TNF)-α, transforming growth factor (TGF)-β, IL-1β, IL-6 and MCP-1 expression significantly. However, C3aR/C5aR-deficient and WT mice with IgAN did not differ with respect to their blood urea nitrogen (BUN) and serum creatinine levels. Our findings provide further support for the idea that C3aR and C5aR are crucially important in IgAN, and suggest that pharmaceutically targeting C3aR/C5aR may hold promise for the treatment of IgAN.
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Affiliation(s)
- Y Zhang
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - X Yan
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - T Zhao
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Q Xu
- Medical Research Council Centre for Transplantation, King's College London, London, UK
| | - Q Peng
- Medical Research Council Centre for Transplantation, King's College London, London, UK
| | - R Hu
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - S Quan
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Y Zhou
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - G Xing
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Min QH, Chen XM, Zou YQ, Zhang J, Li J, Wang Y, Li SQ, Gao QF, Sun F, Liu J, Xu YM, Lin J, Huang LF, Huang B, Wang XZ. Differential expression of urinary exosomal microRNAs in IgA nephropathy. J Clin Lab Anal 2017; 32. [PMID: 28383146 DOI: 10.1002/jcla.22226] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 03/06/2017] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Immunoglobulin A nephropathy (IgAN) is the most common type of primary glomerulonephritis in the world. Reliable biomarkers are required for the non-invasive diagnosis and monitoring of IgAN. This study aims to investigate the difference in urinary exosomal microRNA (miRNA) expression profiles between patients with IgA nephropathy (IgAN) and healthy controls, which may provide clues to identify novel potential non-invasive miRNA biomarkers for renal diseases. METHODS Urine samples were collected from eighteen healthy controls and eighteen patients with IgAN. Differential centrifugation was performed to isolate exosomes from urine samples. High-throughput sequencing and real-time quantitative polymerase chain reaction (RT-qPCR) were sequentially used to screen and further validate miRNA expression profiles in urinary exosomes of patients with IgAN in two independent cohorts. RESULTS Urinary exosomes were successfully isolated to obtain exosomal miRNAs. MiR-215-5p and miR-378i were significantly upregulated in urinary exosomes of patients with IgAN compared with healthy controls (P<.01), while miR-29c and miR-205-5p were significantly downregulated (P<.05). MiR-215-5p, miR-378i, miR-365b-3p and miR-135b-5p were found to have altered expression in patients with IgAN from validation cohorts, which was consistent with the high-throughput sequencing analysis. CONCLUSION This study suggests that there is a significant difference in urinary exosomal miRNA profiles between patients with IgAN and healthy controls. These exosomal miRNAs, such as miR-29c, miR-146a and miR-205 may potentially serve as novel non-invasive biomarkers for IgAN.
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Affiliation(s)
- Qing-Hua Min
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Xi-Min Chen
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Ye-Qing Zou
- Key Laboratory of Molecular Medicine, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Jing Zhang
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Jing Li
- Department of Clinical Laboratory, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yan Wang
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Shu-Qi Li
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Qiu-Fang Gao
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Fan Sun
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Jing Liu
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yan-Mei Xu
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Jin Lin
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Lin-Feng Huang
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Bo Huang
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Xiao-Zhong Wang
- Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University, Nanchang, China
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Berthoux F, Suzuki H, Mohey H, Maillard N, Mariat C, Novak J, Julian BA. Prognostic Value of Serum Biomarkers of Autoimmunity for Recurrence of IgA Nephropathy after Kidney Transplantation. J Am Soc Nephrol 2017; 28:1943-1950. [PMID: 28255003 DOI: 10.1681/asn.2016060670] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 12/20/2016] [Indexed: 11/03/2022] Open
Abstract
A prognostic biomarker for IgA nephropathy (IgAN) recurrence after renal transplant is lacking. We followed 96 consecutive first renal transplant recipients with native kidney IgAN (79 men; 92 deceased donors; mean age =48.1 years) on calcineurin inhibitor-based immunosuppression over 10 years for death, allograft failure, and clinicopathologic recurrence (CPR; clinically evident and biopsy-proven). Using time-dependent Cox regression analysis and receiver operating characteristic curves, we assessed prognostic significance of levels of galactose-deficient IgA1 (Gd-IgA1; autoantigen) and Gd-IgA1-specific IgG and IgA autoantibodies in serum obtained at time of transplant or native-kidney IgAN diagnosis (30 patients only). Overall, 13 patients died, 34 kidneys failed (17 due to CPR), and 34 patients developed CPR after a mean interval of 5.8 years. Compared with healthy controls (n=30), patients had significantly elevated serum Gd-IgA1 levels at diagnosis and transplant, but levels did not associate with any outcome. Patients also had significantly elevated levels of normalized (but not total) serum Gd-IgA1-specific IgG autoantibodies at diagnosis and transplant, and the level at transplant associated with higher risk of CPR (relative risk, 2.68; 95% confidence interval, 1.26 to 5.71; P=0.01; area under the receiver operating characteristic curve, 0.62; 95% confidence interval, 0.51 to 0.74; P=0.05). Normalized Gd-IgA1-specific IgG autoantibody level remained an independent risk factor for CPR in multivariate analysis. Serum Gd-IgA1-specific IgA autoantibody level did not change between diagnosis and transplant or predict outcome. This study emphasizes post-transplant prognostic value of normalized serum IgG antiglycan autoantibody level in patients with IgAN.
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Affiliation(s)
- Francois Berthoux
- Department of Nephrology, Dialysis, and Renal Transplantation, University North Hospital, Saint Etienne, France;
| | - Hitoshi Suzuki
- Division of Nephrology, Department of Internal Medicine, Juntendo University, Tokyo, Japan
| | - Hesham Mohey
- Department of Nephrology, Dialysis, and Renal Transplantation, University North Hospital, Saint Etienne, France
| | - Nicolas Maillard
- Department of Nephrology, Dialysis, and Renal Transplantation, University North Hospital, Saint Etienne, France.,Groupe Immunité des Muqueuses et Agents Pathogènes (GIMAP), Equipe d'Accueil 3064, Saint-Etienne, France; and Departments of
| | - Christophe Mariat
- Department of Nephrology, Dialysis, and Renal Transplantation, University North Hospital, Saint Etienne, France.,Microbiology and
| | | | - Bruce A Julian
- Microbiology and.,Medicine, University of Alabama at Birmingham, Birmingham, Alabama
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81
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The relatively poor correlation between random and 24-hour urine protein excretion in patients with biopsy-proven glomerular diseases. Kidney Int 2016; 90:1080-1089. [PMID: 27528553 DOI: 10.1016/j.kint.2016.06.020] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 06/06/2016] [Accepted: 06/16/2016] [Indexed: 11/20/2022]
Abstract
Random urine protein creatinine ratios are used to estimate 24-hour urine protein excretion, which is considered a diagnostic gold standard. However, few studies are available of the sensitivity and specificity of this estimation in patients with glomerular proteinuria. To clarify this, we measured the urine protein and creatinine centrally in random and 24-hour urine collections at biopsy and longitudinally every 6 months in individuals participating in the Nephrotic Syndrome Study Network (NEPTUNE) cohort with glomerular disease. In the initial developmental cohort, 302 patients had same day random and 24-hour samples with a total of 827 paired measurements across all visits. The protein excretion (g/day) was higher in adult than pediatric patients. The correlation between the random urine protein creatinine ratio and 24-hour urine protein excretion was moderate in both groups (r of 0.60 and 0.67, respectively). However, the log10 transformation of values strengthened correlations in both groups (r of 0.85 and 0.82, respectively). Associations were moderately stronger among obese patients. Prediction equations were developed and validated in 232 unique cases from NEPTUNE (R2 of 0.65). Thus, in patients with glomerular disease and proteinuria, the urine protein creatinine ratio correlates only moderately with 24-hour urine protein excretion. However an estimating equation was developed to derive 24-hour urine protein excretion from random urine protein creatinine ratio values with improved precision. The long-term prognostic value of log10-transformed random protein creatinine ratios values requires future study.
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82
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Yeo SC, Liew A, Barratt J. Emerging therapies in immunoglobulin A nephropathy. Nephrology (Carlton) 2016; 20:788-800. [PMID: 26032537 DOI: 10.1111/nep.12527] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2015] [Indexed: 01/29/2023]
Abstract
Despite advances in our understanding of immunoglobulin A nephropathy (IgAN) over the past decade, there are currently no specific therapies capable of targeting key pathways involved in the pathogenesis of the disease. Recent studies have, however, provided new insights into important molecular pathways that are likely to be amenable to therapeutic manipulation in the future. Specifically, a deeper understanding of the role of mucosal immunity, B-cell activation and mesangial cell activation in IgAN has provided the impetus for a number of exciting phase II/III clinical trials in IgAN. In this review, we examine some of these on-going studies, first examining studies that clarify the role of traditional immunosuppression in IgAN, then focusing on novel therapies in early clinical studies, looking closely at the rationale for these agents in relation to our current understanding of the pathogenesis of IgAN. Finally, we examine emerging pathways and therapeutic agents that have the potential to be developed as novel therapies in the coming years. It is hoped that as we continue to develop a greater understanding of IgAN, emerging therapies will soon become a reality in the day-to-day treatment of patients with IgAN.
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Affiliation(s)
- See Cheng Yeo
- Department of Renal Medicine, Tan Tock Seng Hospital, Singapore
| | - Adrian Liew
- Department of Renal Medicine, Tan Tock Seng Hospital, Singapore
| | - Jonathan Barratt
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK.,The John Walls Renal Unit, Leicester General Hospital, Leicester, UK
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Knoppova B, Reily C, Maillard N, Rizk DV, Moldoveanu Z, Mestecky J, Raska M, Renfrow MB, Julian BA, Novak J. The Origin and Activities of IgA1-Containing Immune Complexes in IgA Nephropathy. Front Immunol 2016; 7:117. [PMID: 27148252 PMCID: PMC4828451 DOI: 10.3389/fimmu.2016.00117] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Accepted: 03/15/2016] [Indexed: 12/12/2022] Open
Abstract
IgA nephropathy (IgAN) is the most common primary glomerulonephritis, frequently leading to end-stage renal disease, as there is no disease-specific therapy. IgAN is diagnosed from pathological assessment of a renal biopsy specimen based on predominant or codominant IgA-containing immunodeposits, usually with complement C3 co-deposits and with variable presence of IgG and/or IgM. The IgA in these renal deposits is galactose-deficient IgA1, with less than a full complement of galactose residues on the O-glycans in the hinge region of the heavy chains. Research from the past decade led to the definition of IgAN as an autoimmune disease with a multi-hit pathogenetic process with contributing genetic and environmental components. In this process, circulating galactose-deficient IgA1 (autoantigen) is bound by antiglycan IgG or IgA (autoantibodies) to form immune complexes. Some of these circulating complexes deposit in glomeruli, and thereby activate mesangial cells and induce renal injury through cellular proliferation and overproduction of extracellular matrix components and cytokines/chemokines. Glycosylation pathways associated with production of the autoantigen and the unique characteristics of the corresponding autoantibodies in patients with IgAN have been uncovered. Complement likely plays a significant role in the formation and the nephritogenic activities of these complexes. Complement activation is mediated through the alternative and lectin pathways and probably occurs systemically on IgA1-containing circulating immune complexes as well as locally in glomeruli. Incidence of IgAN varies greatly by geographical location; the disease is rare in central Africa but accounts for up to 40% of native-kidney biopsies in eastern Asia. Some of this variation may be explained by genetically determined influences on the pathogenesis of the disease. Genome-wide association studies to date have identified several loci associated with IgAN. Some of these loci are associated with the increased prevalence of IgAN, whereas others, such as deletion of complement factor H-related genes 1 and 3, are protective against the disease. Understanding the molecular mechanisms and genetic and biochemical factors involved in formation and activities of pathogenic IgA1-containing immune complexes will enable the development of future disease-specific therapies as well as identification of non-invasive disease-specific biomarkers.
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Affiliation(s)
- Barbora Knoppova
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
| | - Colin Reily
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nicolas Maillard
- Université Jean Monnet, Saint Etienne, France
- PRES Université de Lyon, Lyon, France
| | - Dana V. Rizk
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Zina Moldoveanu
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jiri Mestecky
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Milan Raska
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
- Department of Immunology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
| | - Matthew B. Renfrow
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Bruce A. Julian
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jan Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
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Zhang L, Li J, Yang S, Huang N, Zhou Q, Yang Q, Yu X. Clinicopathological features and risk factors analysis of IgA nephropathy associated with acute kidney injury. Ren Fail 2016; 38:799-805. [PMID: 27050722 DOI: 10.3109/0886022x.2016.1163153] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE The aim of this work is to investigate the distinctive clinicopathological characteristics of AKI in Chinese IgAN population and possible risk factors for AKI. METHODS We performed a retrospective analysis of 1512 patients with biopsy-proven primary IgAN in the period 2006 through 2011 in The First Affiliated Hospital of Sun Yat-sen University. AKI was defined as 2012 KDIGO (Kidney Diseases: Improving Global Outcomes) criteria, and the patients were divided into AKI group (n = 145) and non-AKI group (n = 1367). RESULTS The prevalence of AKI of the IgAN patients in our center was 9.59% (145/1512). Most AKI patients were older age, male, with higher percentage of smoke, hypertension, hyperlipidemia and preexisting impaired kidney function (Scr > 133 μmol/L), and higher serum creatinine, proteinuria, uric acid, whilst less onset of macroscopic hematuria as well as lower serum albumin and hemoglobin (p < 0.05). The pathological features were much more severe in AKI group as well. Acute tubulointerstitial nephritis was found as the most predominant pathological change of intrinsic AKI in our IgAN population instead of macroscopic hematuria associated acute tubular injury/necrosis. In multivariate logistic regression analysis, we found that older age, male gender, malignant hypertension, proteinuria, cellular crescent, fibrocellular crescent, glomerular sclerosis ≥ 50% were possible risk factors for AKI. CONCLUSIONS AKI is commonly seen among IgAN population. The clinicopathological features are much more severe in IgAN patients with AKI. Useful clinicopathological predictors are recognized to improve the identification of IgAN patients who are at high risk for AKI.
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Affiliation(s)
- Ling Zhang
- a Department of Nephrology , The First Affiliated Hospital, Sun Yat-sen University, Key Laboratory of Nephrology, Ministry of Health , Guangzhou , PR China
| | - Jianbo Li
- a Department of Nephrology , The First Affiliated Hospital, Sun Yat-sen University, Key Laboratory of Nephrology, Ministry of Health , Guangzhou , PR China
| | - Shicong Yang
- b Department of Pathology , The First Affiliated Hospital, Sun Yat-sen University , Guangzhou , PR China
| | - Naya Huang
- a Department of Nephrology , The First Affiliated Hospital, Sun Yat-sen University, Key Laboratory of Nephrology, Ministry of Health , Guangzhou , PR China
| | - Qian Zhou
- c Epidemiology Research Unit, Translational Medicine Research Center, The First Affiliated Hospital, Sun Yat-sen University , Guangzhou , PR China
| | - Qiongqiong Yang
- a Department of Nephrology , The First Affiliated Hospital, Sun Yat-sen University, Key Laboratory of Nephrology, Ministry of Health , Guangzhou , PR China
| | - Xueqing Yu
- a Department of Nephrology , The First Affiliated Hospital, Sun Yat-sen University, Key Laboratory of Nephrology, Ministry of Health , Guangzhou , PR China
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85
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Bruchfeld A, Wendt M, Miller EJ. Macrophage Migration Inhibitory Factor in Clinical Kidney Disease. Front Immunol 2016; 7:8. [PMID: 26858715 PMCID: PMC4726817 DOI: 10.3389/fimmu.2016.00008] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 01/11/2016] [Indexed: 11/13/2022] Open
Abstract
Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine implicated in acute and chronic inflammatory conditions, including sepsis, autoimmune disease, atherogenesis, plaque instability, and pulmonary arterial hypertension. MIF in plasma and urine is significantly elevated in patients with acute kidney injury (AKI) and elevated MIF in serum is associated with markers of oxidative stress, endothelial dysfunction, arterial stiffness, and markers of myocardial damage in chronic kidney disease (CKD). Furthermore, MIF seems to be involved in vascular processes and cardiovascular disease associated with CKD, glomerulonephritis, autosomal dominant polycystic kidney disease, and possibly also in progression to renal failure. Moreover, in active anti-neutrophil cytoplasmatic antibody-associated vasculitis, plasma MIF levels have been shown to be significantly elevated as compared with samples from patients in remission. A significant difference in the genotype frequency of high production MIF -173 G/C genotype has been found in end-stage renal disease, compared to controls. Inhibition of MIF in a diabetic nephropathy model ameliorated blood glucose and albuminuria and in a model of adult polycystic kidney disease cyst growth was delayed. Preclinical studies support a potential therapeutic role for MIF in AKI and in a number of CKDs, whereas these data in human disease are still observational. Future interventional studies are needed to delineate the role of MIF as a treatment target in clinical kidney disease.
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Affiliation(s)
- Annette Bruchfeld
- Department of Renal Medicine, Clinical Science Intervention and Technology (CLINTEC), Karolinska Institutet, Karolinska University Hospital , Stockholm , Sweden
| | - Mårten Wendt
- Department of Renal Medicine, Clinical Science Intervention and Technology (CLINTEC), Karolinska Institutet, Karolinska University Hospital , Stockholm , Sweden
| | - Edmund J Miller
- Feinstein Institute for Medical Research, Manhasset, NY, USA; Hofstra University School of Medicine, Hempstead, NY, USA
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Abstract
The IgA nephropathy (IgAN) is a very common glomerulonephritis and can result in end-stage renal disease. From a clinical point of view, IgAN is characterised by repeated events of macrohaematuria associated with infections of the upper airways. In IgAN, the IgA released by the tonsillar lymphatic tissue into blood circulation are defective in glycosylation. These aberrant IgA can reach the glomeruli and deposit into mesangium causing an inflammation with cellular proliferation. The treatment is not yet well defined: steroids and immunosuppressive drugs are suggested in cases with a progressive disease. Tonsillectomy was proposed to reduce the infective events of upper airways and the lymphatic tissue producing undergalactosylated IgA. The experiences in literature coming from Asia report positive effects of tonsillectomy on IgAN. In patients with tonsillectomy, the renal signs improved (less haematuria and proteinuria) and the renal outcome was better (slower progression of renal damage). These were uncontrolled studies and tonsillectomy was associated with steroid and immunosuppressive treatment, so it is not possible to tell the real effect of tonsillectomy. In contrast, the European studies reported that the tonsillectomy was not associated with a better outcome of IgAN. A critical review of the subject reveals that most of the papers with positive results were uncontrolled retrospective experiences, while in a randomised controlled trial paper the advantages of tonsillectomy disappeared. In conclusion, this review, in agreement with the international guidelines, concludes that tonsillectomy does not play any role in the progression of IgAN.
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87
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Prognostic value of endocapillary hypercellularity in IgA nephropathy patients with no immunosuppression. J Nephrol 2015; 29:367-375. [PMID: 26318019 DOI: 10.1007/s40620-015-0227-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 08/20/2015] [Indexed: 12/15/2022]
Abstract
AIM Interpretation of retrospective clinicopathological studies of IgA nephropathy (IgAN) has been confounded by immunosuppression bias. In published validation studies of the Oxford Classification of IgAN, an average of 33 % of patients received non-randomised steroid and/or cytotoxic therapy. In order to determine the true impact of proliferative lesions on the natural history of IgAN, analysis of patient cohorts that have received no immunosuppression is required. METHODS We performed a retrospective single centre study of patients with IgAN managed without immunosuppressive therapy. Biopsies were scored according to the Oxford Classification. The primary outcomes were renal survival or a rapid loss of renal function defined as a decline in eGFR of >5 ml/min/year. RESULTS 237 patients with IgAN were identified with a mean follow-up of 82 months. 200 had biopsies available for review, of which 156 were adequate for scoring using the Oxford Classification. 9/156 patients (5.8 %) received some immunosuppressive therapy, mostly for unrelated conditions: these were excluded. In multivariate COX regression, including histological and clinical data, the only independent predictors of time to ESRD were baseline eGFR (HR 0.96 per ml/min increase, p = 0.018), baseline proteinuria (HR 1.36 per doubling, p = 0.004) and endocapillary hypercellularity (HR 4.75 for E1 compared to E0, p < 0.001). Independent predictors of a rapid decline in eGFR were proteinuria (OR 1.45 per doubling, p = 0.006), endocapillary hypercellularity (OR 3.41 for E1 compared to E0, p = 0.025) and tubular atrophy/interstitial fibrosis (OR 8.77 for T2 compared to T0, p = 0.006). CONCLUSIONS In a cohort of IgAN patients receiving no immunosuppression, endocapillary proliferation and tubular atrophy/interstitial fibrosis are independent predictors of rate of loss of renal function. The lack of predictive value of E score in other clinicopathological studies is most likely a result of immunosuppression-associated bias. Our findings provide evidence to support immunosuppressive treatment of endocapillary-pattern IgAN.
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Park GY, Yu CH, Kim JS, Kang YJ, Kwon O, Choi JY, Cho JH, Kim CD, Kim YL, Park SH. Plasma neutrophil gelatinase-associated lipocalin as a potential predictor of adverse renal outcomes in immunoglobulin A nephropathy. Korean J Intern Med 2015; 30:345-53. [PMID: 25995665 PMCID: PMC4438289 DOI: 10.3904/kjim.2015.30.3.345] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 04/07/2014] [Accepted: 05/29/2014] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND/AIMS Neutrophil gelatinase-associated lipocalin (NGAL) is a well-known biomarker of acute kidney injury. We evaluated the value of plasma NGAL (pNGAL) as an independent predictor of prognosis in immunoglobulin A nephropathy (IgAN). METHODS In total, 91 patients with biopsy-proven IgAN at a single center were evaluated. pNGAL was measured using a commercial enzyme-linked immunosorbent assay kit (R&D Systems). Adverse renal outcome was defined as chronic kidney disease (CKD) stage 3 or above at the last follow-up. Pearson correlation coefficient and Cox regression were used for analyses. RESULTS The mean age of all patients (male:female, 48:43) was 35 years (range, 18 to 77). pNGAL ranged between 21.68 and 446.40 ng/mL (median, 123.97) and showed a correlation with age (r = 0.332, p = 0.001), creatinine (r = 0.336, p = 0.001), estimated glomerular filtration rate (r = -0.397, p < 0.001), uric acid (r = 0.289, p = 0.006), and the protein-to-creatinine ratio (r = 0.288, p = 0.006). During a mean follow-up period of 37.6 months, 11 patients (12.1%) had CKD stage 3 or above. In a multivariate Cox regression model, hypertension (hazard ratio [HR], 8.779; 95% confidence interval [CI], 1.526 to 50.496; p = 0.015), proteinuria > 1 g/day (HR, 5.184; 95% CI, 1.124 to 23.921; p = 0.035), and pNGAL (HR, 1.012; 95% CI, 1.003 to 1.022; p = 0.013) were independent predictors associated with adverse renal outcome. CONCLUSIONS pNGAL showed strong correlations with other clinical prognostic factors and was also an independent predictor of adverse renal outcome. We suggest pNGAL as a potential predictor for prognosis in IgAN, while further studies are needed to confirm the clinical value.
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Affiliation(s)
- Ga-Young Park
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Chung-Hoon Yu
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Jun-Seop Kim
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Yun-Jeong Kang
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Owen Kwon
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Ji-Young Choi
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Jang-Hee Cho
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Chan-Duck Kim
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Yong-Lim Kim
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
| | - Sun-Hee Park
- Department of Internal Medicine, Kyungpook National University School of Medicine and Clinical Research Center for End Stage Renal Disease, Daegu, Korea
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Lemes-Canuto APPS, de Sandes-Freitas TV, Medina-Pestana JO, Mastroianni-Kirsztajn G. IgA NEPHROPATHY IN PATIENTS RECEIVING A RENAL TRANSPLANT. J Ren Care 2015; 41:222-30. [PMID: 25819382 DOI: 10.1111/jorc.12122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND IgA nephropathy (IgAN) is the third most frequent cause of renal graft loss among patients with primary glomerulonephritis. OBJECTIVES To assess clinical and laboratorial profile of patients with pre and/or post transplant IgAN, in addition to patient and graft survival in both groups. DESIGN Data from 146 patients who had received a renal transplant were retrospectively collected and were divided in two groups: group 1-patients with biopsy-documented IgAN as the underlying native kidney disease (n = 128); group 2-patients who developed post-transplant IgAN independent of the underlying disease (n = 18). PARTICIPANTS Patients submitted to renal transplantation (1998-2010) with pre and/or post transplant IgAN. MEASUREMENTS Clinical and laboratorial evaluation of renal function of 146 post transplant IgAN patients. RESULTS Recipients and deceased donors exhibited a higher degree of HLA compatibility (1.0 vs. 2.5 mismatches for groups 1 and 2, respectively). The main post-transplant IgAN presentation was haematuria associated with non-nephrotic proteinuria (44.4%). A histological pattern of focal segmental glomerulosclerosis was observed in 59.2% of biopsy samples. The 10-year patient survival was 93.5% in group 1 and 100% in group 2, and the graft survival rates were 58.5 and 87.2%, respectively. CONCLUSION The rate of post-transplant IgA diagnosis in our case series was 11%, and IgAN was diagnosed late in the course of transplantation. In most cases, IgAN manifested as haematuria and non-nephrotic proteinuria, without renal graft dysfunction, and this picture might explain late indication of graft biopsies. The 10-year patient survival rates were excellent.
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Affiliation(s)
| | | | - José Osmar Medina-Pestana
- Renal Transplant, Unit of the Division of Nephrology, Federal University of São Paulo (UNIFESP), São Paulo, Brazil
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Maillard N, Wyatt RJ, Julian BA, Kiryluk K, Gharavi A, Fremeaux-Bacchi V, Novak J. Current Understanding of the Role of Complement in IgA Nephropathy. J Am Soc Nephrol 2015; 26:1503-12. [PMID: 25694468 DOI: 10.1681/asn.2014101000] [Citation(s) in RCA: 221] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Complement activation has a role in the pathogenesis of IgA nephropathy, an autoimmune disease mediated by pathogenic immune complexes consisting of galactose-deficient IgA1 bound by antiglycan antibodies. Of three complement-activation pathways, the alternative and lectin pathways are involved in IgA nephropathy. IgA1 can activate both pathways in vitro, and pathway components are present in the mesangial immunodeposits, including properdin and factor H in the alternative pathway and mannan-binding lectin, mannan-binding lectin-associated serine proteases 1 and 2, and C4d in the lectin pathway. Genome-wide association studies identified deletion of complement factor H-related genes 1 and 3 as protective against the disease. Because the corresponding gene products compete with factor H in the regulation of the alternative pathway, it has been hypothesized that the absence of these genes could lead to more potent inhibition of complement by factor H. Complement activation can take place directly on IgA1-containing immune complexes in circulation and/or after their deposition in the mesangium. Notably, complement factors and their fragments may serve as biomarkers of IgA nephropathy in serum, urine, or renal tissue. A better understanding of the role of complement in IgA nephropathy may provide potential targets and rationale for development of complement-targeting therapy of the disease.
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Affiliation(s)
- Nicolas Maillard
- University of Alabama at Birmingham, Departments of Microbiology and Medicine, Birmingham, Alabama; Université Jean Monnet, Groupe sur l'immunité des Muqueuses et Agents Pathogènes, St. Etienne, Pôle de Recherche et d'Enseignement Supérieur, Université de Lyon, Lyon, France
| | - Robert J Wyatt
- University of Tennessee Health Science Center and Children's Foundation Research at the Le Bonheur Children's Hospital, Memphis, Tennessee
| | - Bruce A Julian
- University of Alabama at Birmingham, Departments of Microbiology and Medicine, Birmingham, Alabama
| | - Krzysztof Kiryluk
- Columbia University, Department of Medicine, New York, New York; and
| | - Ali Gharavi
- Columbia University, Department of Medicine, New York, New York; and
| | - Veronique Fremeaux-Bacchi
- Unité Mixte de Recherche en Santé 1138, Team "Complement and Diseases," Cordeliers Research Center, Paris, France
| | - Jan Novak
- University of Alabama at Birmingham, Departments of Microbiology and Medicine, Birmingham, Alabama;
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Tesar V, Troyanov S, Bellur S, Verhave JC, Cook HT, Feehally J, Roberts ISD, Cattran D, Coppo R. Corticosteroids in IgA Nephropathy: A Retrospective Analysis from the VALIGA Study. J Am Soc Nephrol 2015; 26:2248-58. [PMID: 25677392 DOI: 10.1681/asn.2014070697] [Citation(s) in RCA: 168] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 11/17/2014] [Indexed: 11/03/2022] Open
Abstract
Current guidelines suggest treatment with corticosteroids (CS) in IgA nephropathy (IgAN) when proteinuria is persistently ≥1 g/d despite 3-6 months of supportive care and when eGFR is >50 ml/min per 1.73 m(2). Whether the benefits of this treatment extend to patients with an eGFR≤50 ml/min per 1.73 m(2), other levels of proteinuria, or different renal pathologic lesions remains unknown. We retrospectively studied 1147 patients with IgAN from the European Validation Study of the Oxford Classification of IgAN (VALIGA) cohort classified according to the Oxford-MEST classification and medication used, with details of duration but not dosing. Overall, 46% of patients received immunosuppression, of which 98% received CS. Treated individuals presented with greater clinical and pathologic risk factors of progression. They also received more antihypertensive medication, and a greater proportion received renin angiotensin system blockade (RASB) compared with individuals without immunosuppressive therapy. Immunosuppression was associated with a significant reduction in proteinuria, a slower rate of renal function decline, and greater renal survival. Using a propensity score, we matched 184 subjects who received CS and RASB to 184 patients with a similar risk profile of progression who received only RASB. Within this group, CS reduced proteinuria and the rate of renal function decline and increased renal survival. These benefits extended to those with an eGFR≤50 ml/min per 1.73 m(2), and the benefits increased proportionally with the level of proteinuria. Thus, CS reduced the risk of progression regardless of initial eGFR and in direct proportion to the extent of proteinuria in this cohort.
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Affiliation(s)
- Vladimir Tesar
- Department of Nephrology, First Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | | | | | | | - H Terence Cook
- Imperial College, Hammersmith Hospital, London, United Kingdom
| | - John Feehally
- University Hospitals of Leicester, Leicester, United Kingdom
| | | | - Daniel Cattran
- University Health Network, Toronto General Hospital, Toronto, Canada; and
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92
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Tesar V, Troyanov S, Bellur S, Verhave JC, Cook HT, Feehally J, Roberts ISD, Cattran D, Coppo R. Corticosteroids in IgA Nephropathy: A Retrospective Analysis from the VALIGA Study. J Am Soc Nephrol 2015. [PMID: 25677392 DOI: 10.1681/asn.201407069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Current guidelines suggest treatment with corticosteroids (CS) in IgA nephropathy (IgAN) when proteinuria is persistently ≥1 g/d despite 3-6 months of supportive care and when eGFR is >50 ml/min per 1.73 m(2). Whether the benefits of this treatment extend to patients with an eGFR≤50 ml/min per 1.73 m(2), other levels of proteinuria, or different renal pathologic lesions remains unknown. We retrospectively studied 1147 patients with IgAN from the European Validation Study of the Oxford Classification of IgAN (VALIGA) cohort classified according to the Oxford-MEST classification and medication used, with details of duration but not dosing. Overall, 46% of patients received immunosuppression, of which 98% received CS. Treated individuals presented with greater clinical and pathologic risk factors of progression. They also received more antihypertensive medication, and a greater proportion received renin angiotensin system blockade (RASB) compared with individuals without immunosuppressive therapy. Immunosuppression was associated with a significant reduction in proteinuria, a slower rate of renal function decline, and greater renal survival. Using a propensity score, we matched 184 subjects who received CS and RASB to 184 patients with a similar risk profile of progression who received only RASB. Within this group, CS reduced proteinuria and the rate of renal function decline and increased renal survival. These benefits extended to those with an eGFR≤50 ml/min per 1.73 m(2), and the benefits increased proportionally with the level of proteinuria. Thus, CS reduced the risk of progression regardless of initial eGFR and in direct proportion to the extent of proteinuria in this cohort.
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Affiliation(s)
- Vladimir Tesar
- Department of Nephrology, First Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | | | | | | | - H Terence Cook
- Imperial College, Hammersmith Hospital, London, United Kingdom
| | - John Feehally
- University Hospitals of Leicester, Leicester, United Kingdom
| | | | - Daniel Cattran
- University Health Network, Toronto General Hospital, Toronto, Canada; and
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93
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Kfoury H, Alsuwaida A, Hussain S, AlOudah N, Alhejaili F, Alsaad K, Alghonaim M. External validation of the Oxford classification of IgA nephropathy: A retrospective study of 70 patients from Saudi Arabia. Int J Organ Transplant Med 2014. [DOI: 10.1016/j.hkjn.2014.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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94
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Kovács T, Vas T, Kövesdy CP, Degrell P, Nagy G, Rékási Z, Wittmann I, Nagy J. Effect of tonsillectomy and its timing on renal outcomes in Caucasian IgA nephropathy patients. Int Urol Nephrol 2014; 46:2175-82. [PMID: 25181956 DOI: 10.1007/s11255-014-0818-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 08/10/2014] [Indexed: 11/26/2022]
Abstract
PURPOSE The role of tonsillectomy in the treatment of IgA nephropathy in Caucasian patients is controversial. METHODS A retrospective cohort study was conducted in 264 patients with biopsy-proven primary IgA nephropathy to examine the association between tonsillectomy and long-term renal survival, defined as the incidence of estimated glomerular filtration rates (eGFRs) of ≤30 ml/min/1.73 m(2) or end-stage renal disease (the composite of initiation of dialysis treatment or renal transplantation). The association of tonsillectomy with renal end-points was examined using the Kaplan-Meier method and Cox models. RESULTS One-hundred and sixty-six patients did not undergo tonsillectomy (Group I, follow-up 130 ± 101 months) and 98 patients underwent tonsillectomy (Group II, follow-up 170 ± 124 months). The mean renal survival time was significantly longer for both end-points between those patients who underwent tonsillectomy (Group II) versus patients without tonsillectomy (Group I) (p < 0.001 and p = 0.005). The mean renal survival time was significantly longer for both end-points between those patients who had macrohaematuric episodes versus patients who had no macrohaematuric episodes (p = 0.035 and p = 0.019). Tonsillectomy, baseline eGFR and 24-h proteinuria were independent risk factors for both renal end-points. CONCLUSION Tonsillectomy may delay the progression of IgA nephropathy mainly in IgA nephropathy patients with macrohaematuria. Prospective investigation of the protective role of tonsillectomy in Caucasian patients is needed.
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Affiliation(s)
- Tibor Kovács
- 2nd Department of Internal Medicine and Nephrological Center, Clinical Center, University of Pécs, Pacsirta Str. 1, Pecs, 7624, Hungary
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95
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Kaartinen K, Syrjänen J, Pörsti I, Harmoinen A, Huhtala H, Mustonen J. Metabolic syndrome in IgA glomerulonephritis. NEPHRON EXTRA 2014; 4:138-45. [PMID: 25337083 PMCID: PMC4164079 DOI: 10.1159/000365591] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Background/Aims Metabolic syndrome (MetS) may have an independent impact on the development of chronic kidney disease. This study examines the prevalence of MetS in subjects with IgA glomerulonephritis (IgAGN) and its impact on disease progression in a retrospective fashion. Patients and Methods Altogether, 174 subjects (104 males) were examined 11 years (first visit) after IgAGN diagnosis and again after 16 years (second visit; 144 subjects responded). Different glomerular filtration markers were utilized. The MetS criteria by Alberti et al. [Circulation 2009;120:1640-1645] were applied, in which the presence of any three of five risk factors (elevated waist circumference, triglycerides, glucose, existence of hypertension, or reduced high-density lipoprotein cholesterol) constitutes the diagnosis. Results The prevalence of MetS at the first visit was 39%, corresponding to that of the general Finnish population. In univariate analyses, MetS was significantly associated with the progression of IgAGN at the second visit. However, in multivariate analyses, the existence of MetS was not a significant prognostic determinant. Conclusion The number of subjects with MetS among IgAGN patients and the general population is equal in Finland. MetS does not seem to be an independent prognostic variable.
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Affiliation(s)
- Kati Kaartinen
- School of Medicine, University of Tampere, Savonlinna, Finland
| | - Jaana Syrjänen
- School of Medicine, University of Tampere, Savonlinna, Finland ; Department of Internal Medicine, Tampere University Hospital, Tampere, Savonlinna, Finland
| | - Ilkka Pörsti
- School of Medicine, University of Tampere, Savonlinna, Finland ; Department of Internal Medicine, Tampere University Hospital, Tampere, Savonlinna, Finland
| | - Aimo Harmoinen
- Department of Laboratory Medicine, Central Hospital of Savonlinna, Savonlinna, Finland
| | - Heini Huhtala
- School of Health Sciences, University of Tampere, Savonlinna, Finland
| | - Jukka Mustonen
- School of Medicine, University of Tampere, Savonlinna, Finland ; Department of Internal Medicine, Tampere University Hospital, Tampere, Savonlinna, Finland
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96
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Nam KH, Kie JH, Lee MJ, Chang TI, Kang EW, Kim DW, Lim BJ, Park JT, Kwon YE, Kim YL, Park KS, An SY, Oh HJ, Yoo TH, Kang SW, Choi KH, Jeong HJ, Han DS, Han SH. Optimal proteinuria target for renoprotection in patients with IgA nephropathy. PLoS One 2014; 9:e101935. [PMID: 25003873 PMCID: PMC4086982 DOI: 10.1371/journal.pone.0101935] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 06/13/2014] [Indexed: 01/13/2023] Open
Abstract
Background Proteinuria is a target for renoprotection in kidney diseases. However, optimal level of proteinuria reduction in IgA nephropathy (IgAN) is unknown. Methods We conducted a retrospective observational study in 500 patients with biopsy-proven IgAN. Time-averaged proteinuria (TA-P) was calculated as the mean of every 6 month period of measurements of spot urine protein-to-creatinine ratio. The study endpoints were a 50% decline in estimated glomerular filtration rate (eGFR), onset of end-stage renal disease (ESRD), and slope of eGFR. Results During a median follow-up duration of 65 (12–154) months, a 50% decline in eGFR occurred in 1 (0.8%) patient with TA-P of <0.3 g/g compared to 6 (2.7%) patients with TA-P of 0.3–0.99 g/g (hazard ratio, 2.82; P = 0.35). Risk of reaching a 50% decline in eGFR markedly increased in patients with TA-P of 1.0–2.99 g/g (P = 0.002) and those with TA-P≥3.0 g/g (P<0.001). ESRD did not occur in patients with TA-P<1.0 g/g compared to 26 (20.0%) and 8 (57.1%) patients with TA-P of 1.0–2.99 and ≥3.0 g/g, respectively. Kidney function of these two groups deteriorated faster than those with TA-P<1.0 g/g (P<0.001). However, patients with TA-P of 0.3–0.99 g/g had a greater decline of eGFR than patients with TA-P<0.3 g/g (−0.41±1.68 vs. −0.73±2.82 ml/min/1.73 m2/year, P = 0.03). Conclusion In this study, patients with TA-P<1.0 g/g show favorable outcomes. However, given the faster eGFR decline in patients with TA-P of 0.3–0.99 g/g than in patients with TA-P<0.3 g/g, the ultimate optimal goal of proteinuria reduction can be lowered in the management of IgAN.
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Affiliation(s)
- Ki Heon Nam
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Jeong Hae Kie
- Department of Pathology, NHIS Ilsan Hospital, Goyang-shi, Gyeonggi-do, Republic of Korea
| | - Mi Jung Lee
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Tae-Ik Chang
- Department of Internal Medicine, NHIS Ilsan Hospital, Goyang-shi, Gyeonggi-do, Republic of Korea
| | - Ea Wha Kang
- Department of Internal Medicine, NHIS Ilsan Hospital, Goyang-shi, Gyeonggi-do, Republic of Korea
| | - Dong Wook Kim
- Biostatistics Collaboration Unit, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Beom Jin Lim
- Department of Pathology, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Jung Tak Park
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Young Eun Kwon
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Yung Ly Kim
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Kyoung Sook Park
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Seong Yeong An
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Hyung Jung Oh
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Tae-Hyun Yoo
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Shin-Wook Kang
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
- Severance Biomedical Science Institute, Brain Korea 21, Yonsei University, Seoul, Republic of Korea
| | - Kyu Hun Choi
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Hyeon Joo Jeong
- Department of Pathology, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Dae-Suk Han
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
| | - Seung Hyeok Han
- Division of Nephrology, Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Republic of Korea
- * E-mail:
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97
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Immunoglobulin A Nephropathy: A Review of Current Literature on Emerging Pathophysiology. Am J Med Sci 2014; 347:249-53. [DOI: 10.1097/maj.0b013e31829406a0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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98
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Liu L, Zhang Y, Duan X, Peng Q, Liu Q, Zhou Y, Quan S, Xing G. C3a, C5a renal expression and their receptors are correlated to severity of IgA nephropathy. J Clin Immunol 2013; 34:224-32. [PMID: 24327134 DOI: 10.1007/s10875-013-9970-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Accepted: 11/11/2013] [Indexed: 10/25/2022]
Abstract
BACKGROUND IgA nephropathy (IgAN) is the most common primary kidney disease, often leading to chronic renal failure. Complement activation products C3a and C5a have broad pro-inflammatory potential through their receptors, C3aR and C5aR, and contribute to the pathogenesis of several inflammatory and autoimmune diseases, but their roles in IgAN are poorly defined. PURPOSE This study aimed to establish correlations between renal C3a, C5a, C3aR, C5aR, or serum/urinary C3a, C5a with clinical features and renal histopathology in patients with IgAN. METHODS Eighty-three patients with renal biopsy proven IgAN were investigated. Thirty patients fulfilled Haas's II, 30 fulfilled Haas's III and 23 fulfilled Haas's IV criteria. Deposition of C3a and C5a was assessed by immunohistochemistry. C3aR and C5aR mRNAs and proteins in kidney tissue were examined by real-time quantitative PCR (RT-qPCR) and immunohistochemical staining, respectively. C3a and C5a levels were quantified by ELISA in serum and urine samples of 30 IgAN patients, 10 control subjects and 10 septic patients. RESULTS Renal C3a and C5a deposition and C3aR and C5aR expression increased with increasing grades of renal pathology in IgAN patients. They positively correlated with proteinuria and serum creatinine (SCr), but not serum C-reactive protein (CRP) or complement 3 (C3). Serum C3a and C5a increased to levels comparable to septic patients but did not differ among IgAN sub-groups. In contrast, urinary C3a and C5a increased significantly and correlated positively with renal pathological grades. CONCLUSIONS In patients with IgAN, urinary and renal C3a and C5a and renal expression of C3aR and C5aR are significantly correlated with the activity and severity of renal injury. This observation warrants further study into the roles of C3a, C5a and their receptors in the pathogenesis of IgAN and as potential therapeutic targets.
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Affiliation(s)
- Lu Liu
- Department of Nephrology, First Affiliated Hospital of Zhengzhou University, Zhengzhou University Institute of Nephrology, Zhengzhou, 450052, China
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99
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Comparison of a Bayesian network with a logistic regression model to forecast IgA nephropathy. BIOMED RESEARCH INTERNATIONAL 2013; 2013:686150. [PMID: 24328031 PMCID: PMC3847960 DOI: 10.1155/2013/686150] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 09/03/2013] [Accepted: 09/26/2013] [Indexed: 11/21/2022]
Abstract
Models are increasingly used in clinical practice to improve the accuracy of diagnosis. The aim of our work was to compare a Bayesian network to logistic regression to forecast IgA nephropathy (IgAN) from simple clinical and biological criteria. Retrospectively, we pooled the results of all biopsies (n = 155) performed by nephrologists in a specialist clinical facility between 2002 and 2009. Two groups were constituted at random. The first subgroup was used to determine the parameters of the models adjusted to data by logistic regression or Bayesian network, and the second was used to compare the performances of the models using receiver operating characteristics (ROC) curves. IgAN was found (on pathology) in 44 patients. Areas under the ROC curves provided by both methods were highly significant but not different from each other. Based on the highest Youden indices, sensitivity reached (100% versus 67%) and specificity (73% versus 95%) using the Bayesian network and logistic regression, respectively. A Bayesian network is at least as efficient as logistic regression to estimate the probability of a patient suffering IgAN, using simple clinical and biological data obtained during consultation.
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100
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Kim MJ, Tam FWK. Currently available and potential future treatment options for IgA nephropathy. Expert Opin Orphan Drugs 2013. [DOI: 10.1517/21678707.2013.821949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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