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Petr V, Csuka D, Hruba P, Szilágyi Á, Kollar M, Slavcev A, Prohászka Z, Viklicky O. MCPggaac haplotype is associated with poor graft survival in kidney transplant recipients with de novo thrombotic microangiopathy. Front Immunol 2022; 13:985766. [PMID: 36189289 PMCID: PMC9519137 DOI: 10.3389/fimmu.2022.985766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 08/24/2022] [Indexed: 11/17/2022] Open
Abstract
De novo thrombotic microangiopathy (TMA) is associated with poor kidney graft survival, and as we previously described, it is a recipient driven process with suspected genetic background. Direct Sanger sequencing was performed in 90 KTR with de novo TMA and 90 corresponding donors on selected regions in CFH, CD46, C3, and CFB genes that involve variations with a functional effect or confer a risk for aHUS. Additionally, 37 recipients of paired kidneys who did not develop TMA were analyzed for the MCPggaac haplotype. Three-years death-censored graft survival was assessed using Kaplan-Meier and Cox regression models. The distribution of haplotypes in all groups was in the Hardy-Weinberg equilibrium and there was no clustering of haplotypes in any group. In the TMA group, we found that MCPggaac haplotype carriers were at a significantly higher risk of graft loss compared to individuals with the wild-type genotype. Worse 3-year death-censored graft survival was associated with longer cold ischemia time (HR 1.20, 95% CI 1.06, 1.36) and recipients’ MCPggaac haplotype (HR 3.83, 95% CI 1.42, 10.4) in the multivariable Cox regression model. There was no association between donor haplotypes and kidney graft survival. Similarly, there was no effect of the MCPggaac haplotype on 3-year graft survival in recipients of paired kidneys without de novo TMA. Kidney transplant recipients carrying the MCPggaac haplotype with de novo TMA are at an increased risk of premature graft loss. These patients might benefit from therapeutic strategies based on complement inhibition.
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Affiliation(s)
- Vojtech Petr
- Department of Nephrology, Institute for Clinical and Experimental Medicine, Prague, Czechia
- First Faculty of Medicine, Charles University, Prague, Czechia
| | - Dorottya Csuka
- Research Laboratory, Department of Internal Medicine and Hematology, Semmelweis University, Budapest, Hungary
| | - Petra Hruba
- Transplant Laboratory, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Ágnes Szilágyi
- Research Laboratory, Department of Internal Medicine and Hematology, Semmelweis University, Budapest, Hungary
| | - Marek Kollar
- Department of Clinical and Transplant Pathology, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Antonij Slavcev
- Department of Immunogenetics, Institute for Clinical and Experimental Medicine, Prague, Czechia
| | - Zoltán Prohászka
- Research Laboratory, Department of Internal Medicine and Hematology, Semmelweis University, Budapest, Hungary
| | - Ondrej Viklicky
- Department of Nephrology, Institute for Clinical and Experimental Medicine, Prague, Czechia
- Transplant Laboratory, Institute for Clinical and Experimental Medicine, Prague, Czechia
- *Correspondence: Ondrej Viklicky,
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Raina R, Sethi SK, Dragon-Durey MA, Khooblall A, Sharma D, Khandelwal P, Shapiro R, Boyer O, Yap HK, Bagga A, Licht C. Systematic review of atypical hemolytic uremic syndrome biomarkers. Pediatr Nephrol 2022; 37:1479-1493. [PMID: 35118546 DOI: 10.1007/s00467-022-05451-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND OBJECTIVES Observing biomarkers that affect alternative pathway dysregulation components may be effective in obtaining a new and more rapid diagnostic portrayal of atypical hemolytic uremic syndrome. We have conducted a systematic review on the aHUS biomarkers: C3, C5a, C5b-9, factor B, complement factor B, H, and I, CH50, AH50, D-dimer, as well as anti-CFH antibodies. METHODS An exhaustive literature search was conducted for aHUS patient population plasma/serum, collected/reported at the onset of diagnosis. A total of 60 studies were included with the data on 837 aHUS subjects, with at least one biomarker reported. RESULTS The biomarkers C3 [mean (SD): 72.1 (35.0), median: 70.5 vs. reference range: 75-175 mg/dl, n = 752]; CH50 [28.3 (32.1), 24.3 vs. 30-75 U/ml, n = 63]; AH50 [27.6% (30.2%), 10% vs. ≥ 46%, n = 23]; and CFB [13.1 (6.6), 12.4, vs. 15.2-42.3 mg/dl, n = 19] were lower among aHUS subjects as compared with the reference range. The biomarkers including C4 [mean (SD): 20.4 (9.5), median: 20.5 vs. reference range: 14-40 mg/dl, n = 343]; C4d [7.2 (6.5), 4.8 vs. ≤ 9.8 μg/ml, n = 108]; CFH [40.2 (132.3), 24.5 vs. 23.6-43.1 mg/dl, n = 123 subjects]; and CFI [8.05 (5.01), 6.55 mg/dl vs. 4.4-18.1 mg/dl, n = 38] were all observed to be within the reference range among aHUS subjects. The biomarkers C5a [mean (SD): 54.9 (32.9), median: 48.8 vs. reference range: 10.6-26.3 mg/dl, n = 117]; C5b-9 [466.0 (401.4), 317 (186-569.7) vs. ≤ 250 ng/ml, n = 174]; Bb [2.6 (2.1), 1.9 vs. ≤ 1.6 μg/ml, n = 77] and D-dimer [246 (65.05), 246 vs. < 2.2 ng/ml, 2, n = 2 subjects] were higher among patients with aHUS compared with the reference range. CONCLUSION If a comprehensive complement profile were built using our data, aHUS would be identified by low levels of C3, CH50, AH50, and CFB along with increased levels of C5a, C5b-9, Bb, anti-CFH autoantibodies, and D-dimer. A higher resolution version of the Graphical abstract is available as Supplementary information.
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Affiliation(s)
- Rupesh Raina
- Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH, USA. .,Department of Nephrology, Akron Children's Hospital, Akron, OH, USA.
| | - Sidharth K Sethi
- Kidney and Renal Transplant Institute, Medanta, The Medicity Hospital, Gurgaon, Haryana, India
| | | | - Amrit Khooblall
- Akron Nephrology Associates/Cleveland Clinic Akron General Medical Center, Akron, OH, USA.,Department of Nephrology, Akron Children's Hospital, Akron, OH, USA
| | - Divya Sharma
- Department of Medicine, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Priyanka Khandelwal
- Division of Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | | | - Olivia Boyer
- Service de Néphrologie Pédiatrique, AP-HP, Centre de Référence de maladies rénales rares de l'enfant et de l'adulte (MARHEA), Hôpital Necker - Enfants Malades, 149 Rue de Sèvres, 75015, Paris, France.,Institut Imagine, Laboratoire des maladies rénales héréditaires, INSERM UMR 1163, Université de Paris, Paris, France
| | - Hui Kim Yap
- Shaw-NKF-NUH Children's Kidney Centre, Khoo Teck Puat-National University Children's Medical Institute, National University Hospital, Kent Ridge, Singapore.,Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Arvind Bagga
- Division of Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - Christoph Licht
- Cell Biology Program, SickKids Research Institute, Toronto, ON, Canada.,Department of Paediatrics, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Division of Nephrology, The Hospital for Sick Children, Toronto, ON, Canada
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3
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Haydock L, Garneau AP, Tremblay L, Yen HY, Gao H, Harrisson R, Isenring P. Genetic abnormalities in biopsy-proven, adult-onset hemolytic uremic syndrome and C3 glomerulopathy. J Mol Med (Berl) 2021; 100:269-284. [PMID: 34714369 PMCID: PMC8770394 DOI: 10.1007/s00109-021-02102-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 12/25/2022]
Abstract
Abstract Atypical hemolytic uremic syndrome (aHUS) and C3 glomerulopathy (C3G) have been linked to mutations in many of the proteins that are involved in alternative complement pathway activation. Age and etiology confounded, the prevalence of such mutations has been reported to be over 30 to 50% in these diseases. However, the cohorts studied included many children or individuals with a familial history of complement-related disorders and genetic tests were usually limited to exome sequencing of known causative or risk-associated genes. In this study, a retrospective adult cohort of 35 patients with biopsy-proven thrombotic microangiopathy (the largest in Canada) and 10 patients with C3 glomerulopathy was tested through an extended exome panel to identify causative defects in associated or candidate genes including those of the alternative and terminal complement pathways. A variant of unknown significance was also analyzed for pathogenicity through in vitro studies. To our surprise, the prevalence of known causative or risk-associated variants in either of these cohorts was found to be less than ~ 15% overall. However, the panel used and analyses carried out allowed to identify novel variants of potential clinical significance and a number of candidate genes. The prevalence of known genetic defects in adult-onset aHUS and C3G is thus probably much lower than 30 to 50%. Our results also point towards the importance of investigating diseases of the alternative complement pathway through extended exome panels and in vitro analyses. Key messages The alternative complement pathway plays a major role in the pathogenesis of hemolytic uremic syndrome and C3 glomerulopathy. Based on previous studies, both disorders have been commonly linked to variants in the various intermediates that sustain or regulate this pathway. The prevalence of such mutations in the adult-onset and sporadic forms of these diseases is probably much lower than expected based on larger series. The sporadic forms of complementopathies are likely to involve additional genes that are yet to be uncovered.
Supplementary information The online version contains supplementary material available at 10.1007/s00109-021-02102-1.
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Affiliation(s)
- Ludwig Haydock
- Nephrology Research Group, L'Hôtel-Dieu de Québec Research Center, Department of Medicine, Faculty of Medicine, Laval University, Quebec, QC, G1R2J6, Canada
| | - Alexandre P Garneau
- Nephrology Research Group, L'Hôtel-Dieu de Québec Research Center, Department of Medicine, Faculty of Medicine, Laval University, Quebec, QC, G1R2J6, Canada.,Cardiometabolic Axis, School of Kinesiology and Physical Activity Sciences, Faculty of Medicine, University of Montréal, 900, rue Saint-Denis, Montreal, QC, H2X 0A9, Canada
| | - Laurence Tremblay
- Nephrology Research Group, L'Hôtel-Dieu de Québec Research Center, Department of Medicine, Faculty of Medicine, Laval University, Quebec, QC, G1R2J6, Canada
| | - Hai-Yun Yen
- Fulgent Genetics, Temple City, CA, 91780, USA
| | - Hanlin Gao
- Fulgent Genetics, Temple City, CA, 91780, USA
| | - Raphaël Harrisson
- Nephrology Research Group, L'Hôtel-Dieu de Québec Research Center, Department of Medicine, Faculty of Medicine, Laval University, Quebec, QC, G1R2J6, Canada
| | - Paul Isenring
- Nephrology Research Group, L'Hôtel-Dieu de Québec Research Center, Department of Medicine, Faculty of Medicine, Laval University, Quebec, QC, G1R2J6, Canada.
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Cabarcas-Barbosa O, Aroca-Martínez G, Musso CG, Ramos-Bolaños E, González-Tórres H, Espitaleta-Vergara Z, Domínguez-Vargas A, Ararat-Rodriguez E, Orozco J, Castillo-Parodi L, Conde-Manotas J, Daza-Arnedo R, Rodríguez-SanJuan V, Gómez-Navarro L, Acosta-Madiedo R, Barros-Camargo L, Aduen-Carrillo A, Ayola-Anaya F, Pulgar-Emiliani M, Cadena-Bonfanti A. Atypical hemolytic uremic syndrome in the Colombian Caribbean: its particular characteristics. Int Urol Nephrol 2021; 54:1323-1330. [PMID: 34643860 PMCID: PMC8513378 DOI: 10.1007/s11255-021-03011-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 10/04/2021] [Indexed: 11/26/2022]
Abstract
Introduction Atypical hemolytic uremic syndrome (aHUS) is a rare and genetically mediated systemic disease most often caused by uncontrolled and chronic complement activation that leads to systemic thrombotic microangiopathy, renal and extra-renal damage. Materials and methods This is descriptive, retrospective and multicenter study, which reports demographic, clinical, laboratory, and genetic characteristics, as well as their treatment response and outcome of 20 aHUS patients diagnosed between 2014 and 2018. Results Most patients were female adults (75%) and 30% were associated to pregnancy/postpartum, 15% to autoimmune disease, and 65% to infections. Gastrointestinal involvement (75%) was the most frequent extra-renal organ damage. Antenatal mortality and mortality rate were 5% and 10%, respectively. 25% of the patients progressed to end-stage renal disease. In 4/8 of patients treated within 1 week of presentation, eculizumab treatment restored multi-organ function after 4 weeks of treatment. CFH (37%) and CFI (25%) mutations were the most frequent. Conclusion This is the first series of aHUS cases of Colombian Caribbean region which reports the clinical and epidemiological characteristics of this condition in this region.
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Affiliation(s)
- Omar Cabarcas-Barbosa
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
- Clínica de la Costa, Barranquilla, Colombia
| | - Gustavo Aroca-Martínez
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
- Clínica de la Costa, Barranquilla, Colombia
| | - Carlos G Musso
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia.
- Unidad de Biología Del Envejecimiento, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.
| | | | - Henry González-Tórres
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
- Clínica de la Costa, Barranquilla, Colombia
| | - Zilac Espitaleta-Vergara
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
- Clínica de la Costa, Barranquilla, Colombia
| | - Alex Domínguez-Vargas
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
| | | | - José Orozco
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
| | - Luis Castillo-Parodi
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
- Clínica de la Costa, Barranquilla, Colombia
| | - Juan Conde-Manotas
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
- Clínica San Rafael, Sabanalarga, Colombia
| | - Rodrigo Daza-Arnedo
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
- Servicio de Cuidados Intensivos Obstétricos, Hospital Niño Jesús, Barranquilla, Colombia
| | | | | | | | | | | | | | - María Pulgar-Emiliani
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
| | - Andrés Cadena-Bonfanti
- Facultad de Ciencias de Ciencias de la Salud, Universidad Simón Bolívar, Barranquilla, Colombia
- Clínica de la Costa, Barranquilla, Colombia
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5
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Lee K, Abraham RS. Next-generation sequencing for inborn errors of immunity. Hum Immunol 2021; 82:871-882. [PMID: 33715910 DOI: 10.1016/j.humimm.2021.02.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/19/2021] [Accepted: 02/23/2021] [Indexed: 12/27/2022]
Abstract
Inborn errors of immunity (IEIs) include several hundred gene defects affecting various components of the immune system. As with other constitutional disorders, next-generation sequencing (NGS) is a powerful tool for the diagnosis of these diseases. While NGS can provide molecular confirmation of disease in a patient with a suspected or classic phenotype, it can also identify new molecular defects of the immune system, expand gene-disease phenotypes, clarify mechanism of disease, pattern of inheritance or identify new gene-disease associations. Multiple clinical specialties are involved in the diagnosis and management of patients with IEI, and most have no formal genetic training or expertise. To effectively utilize NGS tools and data in clinical practice, it is relevant and pragmatic to obtain a modicum of knowledge about genetic terminology, the variety of platforms and tools available for high-throughput genomic analysis, the interpretation and implementation of such data in clinical practice. There is considerable variability not only in the technologies and analytical tools used for NGS but in the bioinformatics approach to variant identification and interpretation. The ability to provide a molecular basis for disease has the potential to alter therapeutic management and longer-term treatment of the disease, including developing personalized approaches with molecularly targeted therapies. This review is intended for the clinical specialist or diagnostic immunologist who works in the area of inborn errors of immunity, and provides an overview of the need for genetic testing in these patients (the "why" aspect), the various technologies and analytical approaches, bioinformatics tools, resources, and challenges (the "how" aspect), and the clinical evidence for identifying which patients might be best served by such testing (the "when" aspect).
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Affiliation(s)
- Kristy Lee
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, The Ohio State University College of Medicine, Columbus, OH, USA; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Roshini S Abraham
- Diagnostic Immunology Laboratory, Department of Pathology and Laboratory Medicine, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, USA; Department of Pathology, The Ohio State University College of Medicine, Columbus, OH, USA.
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6
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Piras R, Iatropoulos P, Bresin E, Todeschini M, Gastoldi S, Valoti E, Alberti M, Mele C, Galbusera M, Cuccarolo P, Benigni A, Remuzzi G, Noris M. Molecular Studies and an ex vivo Complement Assay on Endothelium Highlight the Genetic Complexity of Atypical Hemolytic Uremic Syndrome: The Case of a Pedigree With a Null CD46 Variant. Front Med (Lausanne) 2020; 7:579418. [PMID: 33224962 PMCID: PMC7670076 DOI: 10.3389/fmed.2020.579418] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 09/30/2020] [Indexed: 12/22/2022] Open
Abstract
Atypical hemolytic uremic syndrome (aHUS) is an ultra-rare disease characterized by microangiopathic hemolysis, thrombocytopenia, and renal impairment and is associated with dysregulation of the alternative complement pathway on the microvascular endothelium. Outcomes have improved greatly with pharmacologic complement C5 blockade. Abnormalities in complement genes (CFH, CD46, CFI, CFB, C3, and THBD), CFH–CFHR genomic rearrangements, and anti-FH antibodies have been reported in 40–60% of cases. The penetrance of aHUS is incomplete in carriers of complement gene abnormalities; and multiple hits, including the CFH–H3 and CD46GGAAC risk haplotypes and the CFHR1*B risk allele, as well as environmental factors, contribute to disease development. Here, we investigated the determinants of penetrance of aHUS associated with CD46 genetic abnormalities. We studied 485 aHUS patients and found CD46 rare variants (RVs) in about 10%. The c.286+2T>G RV was the most prevalent (13/485) and was associated with <30% penetrance. We conducted an in-depth study of a large pedigree including a proband who is heterozygous for the c.286+2T>G RV who experienced a severe form of aHUS and developed end-stage renal failure. The father and paternal uncle with the same variant in homozygosity and six heterozygous relatives are unaffected. Flow cytometry analysis showed about 50% reduction of CD46 expression on blood mononuclear cells from the heterozygous proband and over 90% reduction in cells from the proband's unaffected homozygous father and aunt. Further genetic studies did not reveal RVs in known aHUS-associated genes or common genetic modifiers that segregated with the disease. Importantly, a specific ex vivo test showed excessive complement deposition on endothelial cells exposed to sera from the proband, and also from his mother and maternal uncle, who do not carry the c.286+2T>G RV, indicating that they share a circulating defect that results in complement dysregulation on the endothelium. These results highlight the complexity of the genetics of aHUS and indicate that CD46 deficiency may not be enough to induce aHUS. We hypothesize that the proband inherited from his mother a genetic abnormality in a complement circulating factor that has not been identified yet, which synergized with the CD46 RV in predisposing him to the aHUS phenotype.
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Affiliation(s)
- Rossella Piras
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Paraskevas Iatropoulos
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Elena Bresin
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Marta Todeschini
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Sara Gastoldi
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Elisabetta Valoti
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Marta Alberti
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Caterina Mele
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Miriam Galbusera
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Paola Cuccarolo
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Ariela Benigni
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Giuseppe Remuzzi
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Marina Noris
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò,' Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
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Gavriilaki E, Anagnostopoulos A, Mastellos DC. Complement in Thrombotic Microangiopathies: Unraveling Ariadne's Thread Into the Labyrinth of Complement Therapeutics. Front Immunol 2019; 10:337. [PMID: 30891033 PMCID: PMC6413705 DOI: 10.3389/fimmu.2019.00337] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 02/08/2019] [Indexed: 12/20/2022] Open
Abstract
Thrombotic microangiopathies (TMAs) are a heterogeneous group of syndromes presenting with a distinct clinical triad: microangiopathic hemolytic anemia, thrombocytopenia, and organ damage. We currently recognize two major entities with distinct pathophysiology: thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). Beyond them, differential diagnosis also includes TMAs associated with underlying conditions, such as drugs, malignancy, infections, scleroderma-associated renal crisis, systemic lupus erythematosus (SLE), malignant hypertension, transplantation, HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets), and disseminated intravascular coagulation (DIC). Since clinical presentation alone is not sufficient to differentiate between these entities, robust pathophysiological features need to be used for early diagnosis and appropriate treatment. Over the last decades, our understanding of the complement system has evolved rapidly leading to the characterization of diseases which are fueled by complement dysregulation. Among TMAs, complement-mediated HUS (CM-HUS) has long served as a disease model, in which mutations of complement-related genes represent the first hit of the disease and complement inhibition is an effective and safe strategy. Based on this knowledge, clinical conditions resembling CM-HUS in terms of phenotype and genotype have been recognized. As a result, the role of complement in TMAs is rapidly expanding in recent years based on genetic and functional studies. Herein we provide an updated overview of key pathophysiological processes underpinning complement activation and dysregulation in TMAs. We also discuss emerging clinical challenges in streamlining diagnostic algorithms and stratifying TMA patients that could benefit more from complement modulation. With the advent of next-generation complement therapeutics and suitable disease models, these translational perspectives could guide a more comprehensive, disease- and target-tailored complement intervention in these disorders.
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Affiliation(s)
- Eleni Gavriilaki
- BMT Unit, Hematology Department, G. Papanicolaou Hospital, Thessaloniki, Greece
| | | | - Dimitrios C Mastellos
- Division of Biodiagnostic Sciences and Technologies, INRASTES, National Center for Scientific Research Demokritos, Athens, Greece
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8
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Sicre de Fontbrune F, Peffault de Latour R. Ten Years of Clinical Experience With Eculizumab in Patients With Paroxysmal Nocturnal Hemoglobinuria. Semin Hematol 2018; 55:124-129. [DOI: 10.1053/j.seminhematol.2018.04.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 04/03/2018] [Indexed: 12/12/2022]
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9
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Thergaonkar RW, Narang A, Gurjar BS, Tiwari P, Puraswani M, Saini H, Sinha A, Varma B, Mukerji M, Hari P, Bagga A. Targeted exome sequencing in anti-factor H antibody negative HUS reveals multiple variations. Clin Exp Nephrol 2017; 22:653-660. [PMID: 28939980 DOI: 10.1007/s10157-017-1478-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 09/03/2017] [Indexed: 02/01/2023]
Abstract
BACKGROUND Genetic susceptibility to atypical hemolytic uremic syndrome (aHUS) may lie within genes regulating or activating the alternate complement and related pathways converging on endothelial cell activation. METHODS We tested 32 Indian patients of aHUS negative for antibodies to complement factor H for genetic variations in a panel of 15 genes, i.e., CFH, CFHR1-5, CFI, CFB, C3, CD46, MASP2, DGKE, ADAMTS13, THBD and PLG using next-generation DNA sequencing and for copy number variation in CFHR1-3. RESULTS Despite absence of a public database of exome variations in the Indian population and limited functional studies, we could establish a genetic diagnosis in 6 (18.8%) patients using a stringent scheme of prioritization. One patient carried a likely pathogenic variation. The number of patients carrying possibly pathogenic variation was as follows: 1 variation: 5 patients, 2 variations: 9 patients, 3 variations: 5 patients, 4 variations: 9 patients, 5 variations: 2 patients and 6 variations: 2 patients. Homozygous deletion of CFHR1-3 was present in five patients; none of these carried a diagnostic genetic variation. Patients with or without diagnostic variation did not differ significantly in terms of enrichment of genetic variations that were rare/novel or predicted deleterious, or for possible environmental triggers. CONCLUSION We conclude that genetic testing for multiple genes in patients with aHUS negative for anti-FH antibodies reveals multiple candidate variations that require prioritization. Population data on variation frequency of the Indian population and supportive functional studies are likely to improve diagnostic yield.
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Affiliation(s)
- R W Thergaonkar
- Division of Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Ankita Narang
- CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | | | - Pradeep Tiwari
- CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Mamta Puraswani
- Division of Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Himanshi Saini
- Division of Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Aditi Sinha
- Division of Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Binuja Varma
- CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Mitali Mukerji
- CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Pankaj Hari
- Division of Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - Arvind Bagga
- Division of Nephrology, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, 110029, India.
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Quiroga B, de Lorenzo A, Vega C, de Alvaro F. A Case Report and Literature Review of Eculizumab Withdrawal in Atypical Hemolytic-Uremic Syndrome. AMERICAN JOURNAL OF CASE REPORTS 2016; 17:950-956. [PMID: 27974740 PMCID: PMC5179232 DOI: 10.12659/ajcr.899764] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Recent advances in the treatment of atypical hemolytic-uremic syndrome (aHUS) have resulted to better long-term survival rates for patients with this life-threatening disease. However, many questions remain such as whether or not long-term treatment is necessary in some patients and what are the risks of prolonged therapy. CASE REPORT Here, we discuss the case of a 37-year-old woman with CFH and CD46 genetic abnormalities who developed aHUS with severe renal failure. She was successfully treated with three doses of rituximab and a three month treatment with eculizumab. After eculizumab withdrawal, symptoms of thrombotic micro-angiopathy (TMA) recurred, therefore eculizumab treatment was restarted. The patient exhibited normal renal function and no symptoms of aHUS at one-year follow-up with further eculizumab treatment. CONCLUSIONS This case highlights the clinical challenges of the diagnosis and management of patient with aHUS with complement-mediated TMA involvement. Attention was paid to the consequences of the treatment withdrawal. Exact information regarding genetic abnormalities and renal function associated with aHUS, as well as estimations of the relapse risk and monitoring of complement tests may provide insights into the efficacy of aHUS treatment, which will enable the prediction of therapeutic responses and testing of new treatment options. Improvements in our understanding of aHUS and its causes may facilitate the identification of patients in whom anti-complement therapies can be withdrawn without risk.
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11
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The genetic fingerprint of susceptibility for transplant-associated thrombotic microangiopathy. Blood 2015; 127:989-96. [PMID: 26603840 DOI: 10.1182/blood-2015-08-663435] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 11/21/2015] [Indexed: 01/13/2023] Open
Abstract
Transplant-associated thrombotic microangiopathy (TA-TMA) occurs frequently after hematopoietic stem cell transplantation (HSCT) and can lead to significant morbidity and mortality. There are no data addressing individual susceptibility to TA-TMA. We performed a hypothesis-driven analysis of 17 candidate genes known to play a role in complement activation as part of a prospective study of TMA in HSCT recipients. We examined the functional significance of gene variants by using gene expression profiling. Among 77 patients undergoing genetic testing, 34 had TMA. Sixty-five percent of patients with TMA had genetic variants in at least one gene compared with 9% of patients without TMA (P < .0001). Gene variants were increased in patients of all races with TMA, but nonwhites had more variants than whites (2.5 [range, 0-7] vs 0 [range, 0-2]; P < .0001). Variants in ≥3 genes were identified only in nonwhites with TMA and were associated with high mortality (71%). RNA sequencing analysis of pretransplantation samples showed upregulation of multiple complement pathways in patients with TMA who had gene variants, including variants predicted as possibly benign by computer algorithm, compared with those without TMA and without gene variants. Our data reveal important differences in genetic susceptibility to HSCT-associated TMA based on recipient genotype. These data will allow prospective risk assessment and intervention to prevent TMA in highly susceptible transplant recipients. Our findings may explain, at least in part, racial disparities previously reported in transplant recipients and may guide treatment strategies to improve outcomes.
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12
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Mallett A, Hughes P, Szer J, Tuckfield A, Van Eps C, Cambell SB, Hawley C, Burke J, Kausman J, Hewitt I, Parnham A, Ford S, Isbel N. Atypical haemolytic uraemic syndrome treated with the complement inhibitor eculizumab: the experience of the Australian compassionate access cohort. Intern Med J 2015; 45:1054-65. [DOI: 10.1111/imj.12864] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 07/19/2015] [Indexed: 02/03/2023]
Affiliation(s)
- A. Mallett
- Department of Renal Medicine; Royal Brisbane and Women's Hospital; Brisbane Queensland Australia
- Centre for Kidney Disease Research; Centre for Chronic Disease; CKD.QLD; School of Medicine; University of Queensland; Brisbane Queensland Australia
| | - P. Hughes
- Department of Nephrology; Royal Melbourne Hospital; Melbourne Victoria Australia
| | - J. Szer
- Department of Clinical Haematology and BMT Service; Royal Melbourne Hospital; Melbourne Victoria Australia
| | - A. Tuckfield
- Department of Clinical Haematology and BMT Service; Royal Melbourne Hospital; Melbourne Victoria Australia
| | - C. Van Eps
- Centre for Kidney Disease Research; Centre for Chronic Disease; CKD.QLD; School of Medicine; University of Queensland; Brisbane Queensland Australia
- Department of Nephrology; Princess Alexandra Hospital; Brisbane Queensland Australia
| | - S. B. Cambell
- Centre for Kidney Disease Research; Centre for Chronic Disease; CKD.QLD; School of Medicine; University of Queensland; Brisbane Queensland Australia
- Department of Nephrology; Princess Alexandra Hospital; Brisbane Queensland Australia
| | - C. Hawley
- Centre for Kidney Disease Research; Centre for Chronic Disease; CKD.QLD; School of Medicine; University of Queensland; Brisbane Queensland Australia
- Department of Nephrology; Princess Alexandra Hospital; Brisbane Queensland Australia
| | - J. Burke
- Centre for Kidney Disease Research; Centre for Chronic Disease; CKD.QLD; School of Medicine; University of Queensland; Brisbane Queensland Australia
- Department of Nephrology; Princess Alexandra Hospital; Brisbane Queensland Australia
| | - J. Kausman
- Department of Nephrology; The Royal Children's Hospital Melbourne; Melbourne Victoria Australia
| | - I. Hewitt
- Department of Nephrology; Princess Margaret Hospital for Children; Perth Western Australia Australia
| | - A. Parnham
- Department of Nephrology; Gold Coast Hospital; Gold Coast Queensland Australia
| | - S. Ford
- Department of Nephrology; Monash Medical Centre; Melbourne Victoria Australia
| | - N. Isbel
- Centre for Kidney Disease Research; Centre for Chronic Disease; CKD.QLD; School of Medicine; University of Queensland; Brisbane Queensland Australia
- Department of Nephrology; Princess Alexandra Hospital; Brisbane Queensland Australia
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13
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Atypical Hemolytic Uremic Syndrome Recurrence after Renal Transplantation: C3-Glomerulonephritis as an Initial Presentation. Transplant Direct 2015; 1:e9. [PMID: 27500215 PMCID: PMC4946455 DOI: 10.1097/txd.0000000000000518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 02/24/2015] [Indexed: 12/17/2022] Open
Abstract
Risk for atypical hemolytic uremic syndrome (aHUS) recurrence after renal transplantation is low with an isolated membrane cofactor protein mutation (MCP). We report the case of a 32-year-old woman with a MCP who underwent kidney transplantation with a good evolution at 12 months. At 15 and 35 months, 2 episodes of thrombotic microangiopathy (TMA), after a miscarriage and a preeclampsia, were misinterpreted as triggered by tacrolimus. After each episode however serum creatinine returned to baseline. Five years after transplantation, she had a self-limited rhinosinusitis followed 3 weeks later by an oliguric renal failure. Her complement profile was normal. Graft biopsy showed C3 glomerulonephritis with no “humps” on electron microscopy. No significant renal function improvement followed methylprednisolone pulsing. A second biopsy showed severe acute TMA lesions with C3 glomerular deposits. Despite weekly eculizumab for 1 month, dialysis was resumed. A new workup identified the “at-risk” complement factor H haplotype. Thus, aHUS recurrence should be ruled out in aHUS patients considered at low recurrence risk when a TMA is found in graft biopsy. Prompt eculizumab therapy should be considered to avoid graft loss as aHUS recurrence can first present as a C3 glomerulonephritis.
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14
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Assessing complement blockade in patients with paroxysmal nocturnal hemoglobinuria receiving eculizumab. Blood 2015; 125:775-83. [DOI: 10.1182/blood-2014-03-560540] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Key Points
CH50 activity reflects C5 blockade in PNH patients treated with eculizumab and is directly related to circulating free eculizumab levels. Both CH50 and free eculizumab level markers look promising for the monitoring of complement blockade in patients with PNH receiving eculizumab.
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15
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Mapping interactions between complement C3 and regulators using mutations in atypical hemolytic uremic syndrome. Blood 2015; 125:2359-69. [PMID: 25608561 DOI: 10.1182/blood-2014-10-609073] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 01/07/2015] [Indexed: 01/22/2023] Open
Abstract
The pathogenesis of atypical hemolytic uremic syndrome (aHUS) is strongly linked to dysregulation of the alternative pathway of the complement system. Mutations in complement genes have been identified in about two-thirds of cases, with 5% to 15% being in C3. In this study, 23 aHUS-associated genetic changes in C3 were characterized relative to their interaction with the control proteins factor H (FH), membrane cofactor protein (MCP; CD46), and complement receptor 1 (CR1; CD35). In surface plasmon resonance experiments, 17 mutant recombinant proteins demonstrated a defect in binding to FH and/or MCP, whereas 2 demonstrated reduced binding to CR1. In the majority of cases, decreased binding affinity translated to a decrease in proteolytic inactivation (known as cofactor activity) of C3b via FH and MCP. These results were used to map the putative binding regions of C3b involved in the interaction with MCP and CR1 and interrogated relative to known FH binding sites. Seventy-six percent of patients with C3 mutations had low C3 levels that correlated with disease severity. This study expands our knowledge of the functional consequences of aHUS-associated C3 mutations relative to the interaction of C3 with complement regulatory proteins mediating cofactor activity.
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16
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Syndrome hémolytique et urémique atypique : pour qui l’éculizumab ? MEDECINE INTENSIVE REANIMATION 2014. [DOI: 10.1007/s13546-014-0928-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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17
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Tsai HM. A Mechanistic Approach to the Diagnosis and Management of Atypical Hemolytic Uremic Syndrome. Transfus Med Rev 2014; 28:187-97. [DOI: 10.1016/j.tmrv.2014.08.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 08/25/2014] [Accepted: 08/26/2014] [Indexed: 10/24/2022]
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18
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Sansbury FH, Cordell HJ, Bingham C, Bromilow G, Nicholls A, Powell R, Shields B, Smyth L, Warwicker P, Strain L, Wilson V, Goodship JA, Goodship THJ, Turnpenny PD. Factors determining penetrance in familial atypical haemolytic uraemic syndrome. J Med Genet 2014; 51:756-64. [PMID: 25261570 DOI: 10.1136/jmedgenet-2014-102498] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Inherited abnormalities of complement are found in ∼60% of patients with atypical haemolytic uraemic syndrome (aHUS). Such abnormalities are not fully penetrant. In this study, we have estimated the penetrance of the disease in three families with a CFH mutation (c.3643C>G; p. Arg1215Gly) in whom a common lineage is probable. 25 individuals have been affected with aHUS with three peaks of incidence-early childhood (n=6), early adulthood (n=11) and late adulthood (n=8). Eighteen individuals who have not developed aHUS carry the mutation. METHODS We estimated penetrance at the ages of 4, 27, 60 and 70 years as both a binary and a survival trait using MLINK and Mendel. We genotyped susceptibility factors in CFH, CD46 and CFHR1 in affected and unaffected carriers. RESULTS AND CONCLUSIONS We found that the estimates of penetrance at the age of 4 years ranged from <0.01 to 0.10, at the age of 27 years from 0.16 to 0.29, at the age of 60 years from 0.39 to 0.51 and at the age of 70 years from 0.44 to 0.64. We found that the CFH haplotype on the allele not carrying the CFH mutation had a significant effect on disease penetrance. In this family, we did not find that the CD46 haplotypes had a significant effect on penetrance.
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Affiliation(s)
- Francis H Sansbury
- Peninsula Clinical Genetics Service, Royal Devon & Exeter NHS Foundation Trust, Royal Devon & Exeter Hospital (Heavitree), Exeter, UK University of Exeter Medical School, University of Exeter, Exeter, UK Bristol Clinical Genetics Service, University Hospitals Bristol NHS Foundation Trust, Clinical Genetics, St. Michael's Hospital, Bristol, UK
| | - Heather J Cordell
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Coralie Bingham
- University of Exeter Medical School, University of Exeter, Exeter, UK Department of Renal Medicine, Royal Devon & Exeter NHS Foundation Trust, Royal Devon & Exeter Hospital (Wonford), Exeter, UK
| | - Gilly Bromilow
- Peninsula Clinical Genetics Service, Royal Devon & Exeter NHS Foundation Trust, Royal Devon & Exeter Hospital (Heavitree), Exeter, UK
| | - Anthony Nicholls
- Department of Renal Medicine, Royal Devon & Exeter NHS Foundation Trust, Royal Devon & Exeter Hospital (Wonford), Exeter, UK
| | - Roy Powell
- Research Design Service South West, Royal Devon & Exeter NHS Foundation Trust, Royal Devon & Exeter Hospital (Wonford), Exeter, UK
| | - Bev Shields
- University of Exeter Medical School, University of Exeter, Exeter, UK
| | - Lucy Smyth
- Department of Renal Medicine, Royal Devon & Exeter NHS Foundation Trust, Royal Devon & Exeter Hospital (Wonford), Exeter, UK
| | - Paul Warwicker
- Lister Renal Units, East and North Hertfordshire NHS Trust, Stevenage, UK
| | - Lisa Strain
- Northern Molecular Genetics Service, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Valerie Wilson
- Northern Molecular Genetics Service, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Judith A Goodship
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | | | - Peter D Turnpenny
- Peninsula Clinical Genetics Service, Royal Devon & Exeter NHS Foundation Trust, Royal Devon & Exeter Hospital (Heavitree), Exeter, UK University of Exeter Medical School, University of Exeter, Exeter, UK
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19
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Abstract
Hemolytic uremic syndrome (HUS) is a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. The atypical form of HUS is a disease characterized by complement overactivation. Inherited defects in complement genes and acquired autoantibodies against complement regulatory proteins have been described. Incomplete penetrance of mutations in all predisposing genes is reported, suggesting that a precipitating event or trigger is required to unmask the complement regulatory deficiency. The underlying genetic defect predicts the prognosis both in native kidneys and after renal transplantation. The successful trials of the complement inhibitor eculizumab in the treatment of atypical HUS will revolutionize disease management.
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Affiliation(s)
- David Kavanagh
- The Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK.
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20
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Marinozzi MC, Vergoz L, Rybkine T, Ngo S, Bettoni S, Pashov A, Cayla M, Tabarin F, Jablonski M, Hue C, Smith RJ, Noris M, Halbwachs-Mecarelli L, Donadelli R, Fremeaux-Bacchi V, Roumenina LT. Complement factor B mutations in atypical hemolytic uremic syndrome-disease-relevant or benign? J Am Soc Nephrol 2014; 25:2053-65. [PMID: 24652797 DOI: 10.1681/asn.2013070796] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Atypical hemolytic uremic syndrome (aHUS) is a genetic ultrarare renal disease associated with overactivation of the alternative pathway of complement. Four gain-of-function mutations that form a hyperactive or deregulated C3 convertase have been identified in Factor B (FB) ligand binding sites. Here, we studied the functional consequences of 10 FB genetic changes recently identified from different aHUS cohorts. Using several tests for alternative C3 and C5 convertase formation and regulation, we identified two gain-of-function and potentially disease-relevant mutations that formed either an overactive convertase (M433I) or a convertase resistant to decay by FH (K298Q). One mutation (R178Q) produced a partially cleaved protein with no ligand binding or functional activity. Seven genetic changes led to near-normal or only slightly reduced ligand binding and functional activity compared with the most common polymorphism at position 7, R7. Notably, none of the algorithms used to predict the disease relevance of FB mutations agreed completely with the experimental data, suggesting that in silico approaches should be undertaken with caution. These data, combined with previously published results, suggest that 9 of 15 FB genetic changes identified in patients with aHUS are unrelated to disease pathogenesis. This study highlights that functional assessment of identified nucleotide changes in FB is mandatory to confirm disease association.
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Affiliation(s)
- Maria Chiara Marinozzi
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Assistance Publique-Hôpitaux de Paris, Service d'Immunologie Biologique, Hôpital Européen Georges Pompidou, Paris, France
| | - Laura Vergoz
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Université Pierre et Marie Curie (Paris-6), Paris, France
| | - Tania Rybkine
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Université Pierre et Marie Curie (Paris-6), Paris, France
| | - Stephanie Ngo
- Assistance Publique-Hôpitaux de Paris, Service d'Immunologie Biologique, Hôpital Européen Georges Pompidou, Paris, France
| | - Serena Bettoni
- IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Clinical Research Center for Rare Diseases Aldo e Cele Daccò, Ranica, Bergamo, Italy
| | - Anastas Pashov
- Molecular Medicine, Stephan Angelov Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Mathieu Cayla
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Université Pierre et Marie Curie (Paris-6), Paris, France
| | - Fanny Tabarin
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Université Pierre et Marie Curie (Paris-6), Paris, France
| | - Mathieu Jablonski
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Université Pierre et Marie Curie (Paris-6), Paris, France
| | - Christophe Hue
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Université Pierre et Marie Curie (Paris-6), Paris, France
| | - Richard J Smith
- Molecular Otolaryngology and Renal Research Laboratories and Rare Renal Disease Clinic, Departments of Pediatrics and Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - Marina Noris
- Laboratory of Immunology and Genetics of Transplantation and Rare Diseases, Mario Negri Institute for Pharmacological Research, Ranica, Bergamo, Italy
| | - Lise Halbwachs-Mecarelli
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Université Pierre et Marie Curie (Paris-6), Paris, France
| | - Roberta Donadelli
- IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Clinical Research Center for Rare Diseases Aldo e Cele Daccò, Ranica, Bergamo, Italy
| | - Veronique Fremeaux-Bacchi
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Assistance Publique-Hôpitaux de Paris, Service d'Immunologie Biologique, Hôpital Européen Georges Pompidou, Paris, France
| | - Lubka T Roumenina
- Institut National de la Santé et de la Recherche Médicale UMRS 1138, Cordeliers Research Center, Complement and Diseases Team, Paris, France; Université Paris Descartes Sorbonne Paris-Cité, Paris, France; Université Pierre et Marie Curie (Paris-6), Paris, France;
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Frémeaux-Bacchi V. [Pathophysiology of atypical hemolytic uremic syndrome. Ten years of progress, from laboratory to patient]. Biol Aujourdhui 2014; 207:231-40. [PMID: 24594571 DOI: 10.1051/jbio/2013027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Indexed: 11/14/2022]
Abstract
Hemolytic Uremic Syndrome (HUS) is characterized by the triad of hemolytic anemia, thrombocytopenia and acute renal failure. The most frequent form in children is caused by Shiga-toxin producing Escherichia coli. In absence of Shiga-toxin infection, the HUS is called atypical (aHUS). Some HUS are secondary to Streptococcus pneumonia or human immunodeficiency virus infection, cancer, anti-cancer drugs, or cyclosporine. During the last decade, aHUS has been demonstrated to be a disorder of complement alternative pathway regulation. aHUS must be regarded as a complex polygenic disease which results from a combination of genetic risk factors. Approximately 60% of patients have mutations in the genes encoding complement factor H (20-30% of patients), MCP (10-15%), factor I (4-10%), factor B (1-2%) or C3 (5-10%), and 6% have anti-factor H antibodies. Prognosis is severe whereas the clinical features vary according to complement abnormality. aHUS touches both children and adults, but in children very early onset is characteristic of factor H and factor I-HUS, while MCP-HUS is not observed before the age of 1. Half of patients with adult onset have a rapid evolution to end-stage renal disease, but half recover. The best prognosis is in patients with MCP (Membrane Cofactor Protein) mutation and a pediatric onset of the disease, who have a relapsing course, but a risk of end-stage renal disease of only 15-30% at 5 years follow-up. Anti-factor H antibodies-HUS is mainly observed in (pre)adolescents and appears to have a favourable outcome if treated early. There is a high risk of post-transplant recurrence in all groups, except MCP-HUS. These findings have paved the way for innovative therapeutic strategies based on complement blockade, and eculizumab, a monoclonal antibody targeting the human complement component 5, is now widely used to treat aHUS. Mutations in the gene of thrombomodulin and diacylglycerol kinase epsilon (DGKe) have been reported, suggesting the possibility of an alternative or more complex disease-causing mechanism than previously thought.
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Affiliation(s)
- Véronique Frémeaux-Bacchi
- INSERM UMR_S1135, Centre de Recherche des Cordeliers, Équipe « Complément et Maladies », 15 rue de l'École de Médecine, 75006 Paris, France - Hôpital Européen Georges Pompidou, Laboratoire d'Immunologie, 20 rue Leblanc, 75015 Paris, France
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22
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Tsai HM. Thrombotic thrombocytopenic purpura and the atypical hemolytic uremic syndrome: an update. Hematol Oncol Clin North Am 2013; 27:565-84. [PMID: 23714312 DOI: 10.1016/j.hoc.2013.02.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Since the last review in 2007 of thrombotic thrombocytopenic purpura (TTP) and microangiopathic hemolytic anemia in the Clinics, further understanding of the nature of TTP and atypical hemolytic uremic syndrome (aHUS) has led to increasing use of rituximab in the treatment of TTP and the approval in 2011 of eculizumab for the treatment of aHUS. With this new armamentarium, distinction of aHUS from TTP has become more critical than ever. This article updates the new knowledge, highlights the difference between aHUS and TTP, and presents a scheme for their diagnosis and management.
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Affiliation(s)
- Han-Mou Tsai
- iMAH Hematology Associates, New Hyde Park, New York, NY 11040, USA.
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23
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Bu F, Maga T, Meyer NC, Wang K, Thomas CP, Nester CM, Smith RJH. Comprehensive genetic analysis of complement and coagulation genes in atypical hemolytic uremic syndrome. J Am Soc Nephrol 2013; 25:55-64. [PMID: 24029428 DOI: 10.1681/asn.2013050453] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Atypical hemolytic uremic syndrome (aHUS) is a thrombotic microangiopathy caused by uncontrolled activation of the alternative pathway of complement at the cell surface level that leads to microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney failure. In approximately one half of affected patients, pathogenic loss-of-function variants in regulators of complement or gain-of-function variants in effectors of complement are identified, clearly implicating complement in aHUS. However, there are strong lines of evidence supporting the presence of additional genetic contributions to this disease. To identify novel aHUS-associated genes, we completed a comprehensive screen of the complement and coagulation pathways in 36 patients with sporadic aHUS using targeted genomic enrichment and massively parallel sequencing. After variant calling, quality control, and hard filtering, we identified 84 reported or novel nonsynonymous variants, 22 of which have been previously associated with disease. Using computational prediction methods, 20 of the remaining 62 variants were predicted to be deleterious. Consistent with published data, nearly one half of these 42 variants (19; 45%) were found in genes implicated in the pathogenesis of aHUS. Several genes in the coagulation pathway were also identified as important in the pathogenesis of aHUS. PLG, in particular, carried more pathogenic variants than any other coagulation gene, including three known plasminogen deficiency mutations and a predicted pathogenic variant. These data suggest that mutation screening in patients with aHUS should be broadened to include genes in the coagulation pathway.
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24
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Wilson V, Darlay R, Wong W, Wood KM, McFarlane J, Schejbel L, Schmidt IM, Harris CL, Tellez J, Hunze EM, Marchbank K, Goodship JA, Goodship THJ. Genotype/phenotype correlations in complement factor H deficiency arising from uniparental isodisomy. Am J Kidney Dis 2013; 62:978-83. [PMID: 23870792 DOI: 10.1053/j.ajkd.2013.05.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 05/15/2013] [Indexed: 11/11/2022]
Abstract
We report a male infant who presented at 8 months of age with atypical hemolytic uremic syndrome (aHUS) responsive to plasma therapy. Investigation showed him to have complement factor H (CFH) deficiency associated with a homozygous CFH mutation (c.2880delT [p.Phe960fs]). Mutation screening of the child's parents revealed that the father was heterozygous for this change but that it was not present in his mother. Chromosome 1 uniparental isodisomy of paternal origin was confirmed by genotyping chromosome 1 SNPs. CD46 SNP genotyping was undertaken in this individual and another patient with CFH deficiency associated with chromosome 1 uniparental isodisomy. This showed a homozygous aHUS risk haplotype (CD46GGAAC) in the patient with aHUS and a homozygous glomerulonephritis risk haplotype (CD46AAGGT) in the patient with endocapillary glomerulonephritis. We also showed that FHL-1 (factor H-like protein 1) was present in the patient with aHUS and absent in the patient with glomerulonephritis. This study emphasizes that modifiers such as CD46 and FHL-1 may determine the kidney phenotype of patients who present with homozygous CFH deficiency.
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Affiliation(s)
- Valerie Wilson
- Northern Molecular Genetics Service, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom
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Wong EKS, Goodship THJ, Kavanagh D. Complement therapy in atypical haemolytic uraemic syndrome (aHUS). Mol Immunol 2013; 56:199-212. [PMID: 23810412 PMCID: PMC3899040 DOI: 10.1016/j.molimm.2013.05.224] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Accepted: 05/10/2013] [Indexed: 12/22/2022]
Abstract
Central to the pathogenesis of atypical haemolytic uraemic syndrome (aHUS) is over-activation of the alternative pathway of complement. Inherited defects in complement genes and autoantibodies against complement regulatory proteins have been described. The use of plasma exchange to replace non-functioning complement regulators and hyper-functional complement components in addition to the removal of CFH-autoantibodies made this the ‘gold-standard’ for management of aHUS. In the last 4 years the introduction of the complement inhibitor Eculizumab has revolutionised the management of aHUS. In this review we shall discuss the available literature on treatment strategies to date.
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Affiliation(s)
- Edwin K S Wong
- The Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
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26
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Bibliography. Current world literature. Neonatology and perinatology. Curr Opin Pediatr 2013; 25:275-81. [PMID: 23481475 DOI: 10.1097/mop.0b013e32835f58ca] [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: 11/26/2022]
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Tsai HM. Untying the knot of thrombotic thrombocytopenic purpura and atypical hemolytic uremic syndrome. Am J Med 2013; 126:200-9. [PMID: 23410558 DOI: 10.1016/j.amjmed.2012.09.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 09/07/2012] [Accepted: 09/07/2012] [Indexed: 01/06/2023]
Abstract
Patients presenting with microangiopathic hemolysis and thrombocytopenia are often given the diagnosis of thrombotic thrombocytopenic purpura and treated with plasma exchange until the acute episode is over. Recent findings have shown that acquired thrombotic thrombocytopenic purpura is a chronic autoimmune disease with inhibitory antibodies of a disintegrin and metalloprotease with thrombospondin repeat, member 13 and are at risk of relapses that may be preventable. Furthermore, many of the patients given the diagnosis of thrombotic thrombocytopenic purpura really have atypical hemolytic uremic syndrome due to defective complement regulation that can be more effectively treated to prevent death and end-stage renal failure with eculizumab, a humanized monoclonal antibody of complement C5. These advances indicate that an accurate differential diagnosis of microangiopathic hemolysis is essential for optimal patient management.
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Affiliation(s)
- Han-Mou Tsai
- iMAH Hematology Associates, New Hyde Park, NY 11040, USA.
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Le Quintrec M, Zuber J, Moulin B, Kamar N, Jablonski M, Lionet A, Chatelet V, Mousson C, Mourad G, Bridoux F, Cassuto E, Loirat C, Rondeau E, Delahousse M, Frémeaux-Bacchi V. Complement genes strongly predict recurrence and graft outcome in adult renal transplant recipients with atypical hemolytic and uremic syndrome. Am J Transplant 2013; 13:663-75. [PMID: 23356914 DOI: 10.1111/ajt.12077] [Citation(s) in RCA: 186] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 11/25/2012] [Accepted: 11/27/2012] [Indexed: 01/25/2023]
Abstract
Atypical hemolytic and uremic syndrome (aHUS) is a severe disease strongly associated with genetic abnormalities in the complement alternative pathway. In renal posttransplantation, few data are available on recurrence risk and graft outcome according to genetic background in aHUS patients. The aim of this study was to identify risk factors for recurrence and transplant outcome and, in particular, the role of complement gene abnormalities. We retrospectively studied 57 aHUS patients who had received 71 renal transplants. A mutation in complement gene was identified in 39 (68%), in factor H (CFH), factor I (CFI), membrane cofactor-protein (MCP), C3 and factor B (CFB). At 5 years, death-censored graft survival was 51%. Disease recurrence was associated with graft loss (p = 0.001). Mutations in complement genes were associated with higher risk of recurrence (p = 0.009). Patients with CFH or gain of function (C3, CFB) mutations had a highest risk of recurrence. M-TOR inhibitor was associated with significant risk of recurrence (p = 0.043) but not calcineurin inhibitor immunosuppressive treatment (p = 0.29). Preemptive plasmatherapy was associated with a trend to decrease recurrence (p = 0.07). Our study highlights that characterization of complement genetic abnormalities predicts the risk of recurrence-related graft loss and paves the way for future genetically based individualized prophylactic therapeutic strategies.
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Affiliation(s)
- M Le Quintrec
- Néphrologie et Transplantation Rénale, Hôpital Foch, Suresnes, France.
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Fremeaux-Bacchi V, Fakhouri F, Garnier A, Bienaimé F, Dragon-Durey MA, Ngo S, Moulin B, Servais A, Provot F, Rostaing L, Burtey S, Niaudet P, Deschênes G, Lebranchu Y, Zuber J, Loirat C. Genetics and outcome of atypical hemolytic uremic syndrome: a nationwide French series comparing children and adults. Clin J Am Soc Nephrol 2013; 8:554-62. [PMID: 23307876 DOI: 10.2215/cjn.04760512] [Citation(s) in RCA: 512] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND OBJECTIVES Atypical hemolytic uremic syndrome (aHUS) is a rare complement-mediated kidney disease that was first recognized in children but also affects adults. This study assessed the disease presentation and outcome in a nationwide cohort of patients with aHUS according to the age at onset and the underlying complement abnormalities. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS A total of 214 patients with aHUS were enrolled between 2000 and 2008 and screened for mutations in the six susceptibility factors for aHUS and for anti-factor H antibodies. RESULTS Onset of aHUS occurred as frequently during adulthood (58.4%) as during childhood (41.6%). The percentages of patients who developed the disease were 23%, 40%, 70%, and 98% by age 2, 18, 40, and 60 years, respectively. Mortality was higher in children than in adults (6.7% versus 0.8% at 1 year) (P=0.02), but progression to ESRD after the first aHUS episode was more frequent in adults (46% versus 16%; P<0.001). Sixty-one percent of patients had mutations in their complement genes. The renal outcome was not significantly different in adults regardless of genetic background. Only membrane cofactor protein (MCP) and undetermined aHUS were less severe in children than adults. The frequency of relapse after 1 year was 92% in children with MCP-associated HUS and approximately 30% in all other subgroups. CONCLUSION Mortality rate was higher in children than adults with aHUS, but renal prognosis was worse in adults than children. In children, the prognosis strongly depends on the genetic background.
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Affiliation(s)
- Véronique Fremeaux-Bacchi
- Service d'Immunologie Biologique, Hôpital Europeén Georges Pompidou, 20-40 rue Leblanc, Paris cedex 15, France.
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Familial atypical hemolytic uremic syndrome: a review of its genetic and clinical aspects. Clin Dev Immunol 2012; 2012:370426. [PMID: 23251215 PMCID: PMC3509654 DOI: 10.1155/2012/370426] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 09/24/2012] [Indexed: 12/27/2022]
Abstract
Atypical hemolytic uremic syndrome (aHUS) is a rare renal disease (two per one million in the USA) characterized by microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. Both sporadic (80% of cases) and familial (20% of cases) forms are recognized. The study of familial aHUS has implicated genetic variation in multiple genes in the complement system in disease pathogenesis, helping to define the mechanism whereby complement dysregulation at the cell surface level leads to both sporadic and familial disease. This understanding has culminated in the use of Eculizumab as first-line therapy in disease treatment, significantly changing the care and prognosis of affected patients. However, even with this bright outlook, major challenges remain to understand the complexity of aHUS at the genetic level. It is possible that a more detailed picture of aHUS can be translated to an improved understanding of disease penetrance, which is highly variable, and response to therapy, both in the short and long terms.
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Barbour T, Johnson S, Cohney S, Hughes P. Thrombotic microangiopathy and associated renal disorders. Nephrol Dial Transplant 2012; 27:2673-85. [PMID: 22802583 PMCID: PMC3398067 DOI: 10.1093/ndt/gfs279] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 04/07/2012] [Indexed: 12/17/2022] Open
Abstract
Thrombotic microangiopathy (TMA) is a pathological process involving thrombocytopenia, microangiopathic haemolytic anaemia and microvascular occlusion. TMA is common to haemolytic uraemic syndrome (HUS) associated with shiga toxin or invasive pneumococcal infection, atypical HUS (aHUS), thrombotic thrombocytopenic purpura (TTP) and other disorders including malignant hypertension. HUS complicating infection with shiga toxin-producing Escherichia coli (STEC) is a significant cause of acute renal failure in children worldwide, occurring sporadically or in epidemics. Studies in aHUS have revealed genetic and acquired factors leading to dysregulation of the alternative complement pathway. TTP has been linked to reduced activity of the ADAMTS13 cleaving protease (typically with an autoantibody to ADAMTS13) with consequent disruption of von Willebrand factor multimer processing. However, the convergence of pathogenic pathways and clinical overlap create diagnostic uncertainty, especially at initial presentation. Furthermore, recent developments are challenging established management protocols. This review addresses the current understanding of molecular mechanisms underlying TMA, relating these to clinical presentation with an emphasis on renal manifestations. A diagnostic and therapeutic approach is presented, based on international guidelines, disease registries and published trials. Early treatment remains largely empirical, consisting of plasma replacement/exchange with the exception of childhood STEC-HUS or pneumococcal sepsis. Emerging therapies such as the complement C5 inhibitor eculizumab for aHUS and rituximab for TTP are discussed, as is renal transplantation for those patients who become dialysis-dependent as a result of aHUS.
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Affiliation(s)
- Thomas Barbour
- Imperial College, Centre for Complement and Inflammation Research, London, UK.
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