1
|
Coorey CP, de Malmanche T, Chou A, Feddersen M. Complement-mediated thrombotic microangiopathy on a background of Alport syndrome: A case report. Nephrology (Carlton) 2024. [PMID: 38604610 DOI: 10.1111/nep.14305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/10/2024] [Accepted: 04/02/2024] [Indexed: 04/13/2024]
Abstract
Here we present a case of complement-mediated thrombotic microangiopathy (TMA) in a patient who has a background of Stage 5 chronic kidney disease secondary to Alport syndrome. We explain our approach to the diagnosis of TMA, especially the reliance on non-renal manifestations of TMA and the role of kidney biopsy given there was a background of advanced kidney impairment at baseline.
Collapse
Affiliation(s)
- Craig Peter Coorey
- Renal Unit, Gosford Hospital, Gosford, New South Wales, Australia
- School of Medicine, Western Sydney University, Campbelltown, New South Wales, Australia
| | - Theo de Malmanche
- Immunology, NSW Health Pathology, Newcastle, New South Wales, Australia
- School of Medicine and Public Health, University of Newcastle, Callaghan, New South Wales, Australia
| | - Angela Chou
- Department of Anatomical Pathology, Royal North Shore Hospital, St Leonards, New South Wales, Australia
| | - Martin Feddersen
- Renal Unit, Gosford Hospital, Gosford, New South Wales, Australia
| |
Collapse
|
2
|
Liu N, Wen X, Ou Z, Fang X, Du J, Lin X. Case report: Preimplantation genetic testing for X-linked alport syndrome caused by variation in the COL4A5 gene. Front Pediatr 2023; 11:1177019. [PMID: 37635800 PMCID: PMC10448762 DOI: 10.3389/fped.2023.1177019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 07/28/2023] [Indexed: 08/29/2023] Open
Abstract
X-Linked Alport Syndrome (XLAS) is an X-linked, dominant, hereditary nephropathy mainly caused by mutations in the COL4A5 gene, found on chromosome Xq22. In this study, we reported a pedigree with XLAS caused by a COL4A5 mutation. This family gave birth to a boy with XLAS who developed hematuria and proteinuria at the age of 1 year. We used next-generation sequencing (NGS) to identify mutations in the proband and his parents and confirmed the results using Sanger sequencing. This testing showed there was a single nucleotide missense variation, c.3659G>A (p.Gly1220Asp) (NM_033380.3), in the COL4A5 gene. To prevent the inheritance of the syndrome, we used eight embryos for trophoblast biopsy after assisted reproductive technology treatment, and whole genome amplification (WGA) was performed using multiple annealing and looping-based amplification cycles (MALBAC). Embryos were subjected to Preimplantation Genetic Testing (PGT) procedures, including Sanger sequencing, NGS-based single nucleotide polymorphism (SNP) haplotype linkage analysis, and chromosomal copy number variation (CNV) analysis. The results showed that three embryos (E1, E2, and E4) were free of CNV and genetic variation in the COL4A5 gene. Embryo E1 (4AA) was transferred after consideration of the embryo growth rate, morphology, and PGT results. Prenatal diagnosis in the second trimester showed that the fetus had a normal karyotype and did not carry the COL4A5 mutation (c.3659G>A). Ultimately, a healthy boy was born and did not carry the pathogenic COL4A5 mutation, which indicated that PGT prevented the intergenerational transmission of the causative mutation of XLAS.
Collapse
Affiliation(s)
- Nengqing Liu
- Reproductive Center, Zhongshan Boai Hospital, Zhongshan, China
| | - Xiaojun Wen
- Reproductive Center, Zhongshan Boai Hospital, Zhongshan, China
| | - Zhanhui Ou
- Reproductive Center, Zhongshan Boai Hospital, Zhongshan, China
| | - Xiaowu Fang
- Reproductive Center, Zhongshan Boai Hospital, Zhongshan, China
| | - Jing Du
- Reproductive Center, Zhongshan Boai Hospital, Zhongshan, China
| | - Xiufeng Lin
- Reproductive Center, Zhongshan Boai Hospital, Zhongshan, China
- The Second Clinical College, Southern Medical University, Guangzhou, China
| |
Collapse
|
3
|
Groopman EE, Povysil G, Goldstein DB, Gharavi AG. Rare genetic causes of complex kidney and urological diseases. Nat Rev Nephrol 2020; 16:641-656. [PMID: 32807983 PMCID: PMC7772719 DOI: 10.1038/s41581-020-0325-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/03/2020] [Indexed: 02/08/2023]
Abstract
Although often considered a single-entity, chronic kidney disease (CKD) comprises many pathophysiologically distinct disorders that result in persistently abnormal kidney structure and/or function, and encompass both monogenic and polygenic aetiologies. Rare inherited forms of CKD frequently span diverse phenotypes, reflecting genetic phenomena including pleiotropy, incomplete penetrance and variable expressivity. Use of chromosomal microarray and massively parallel sequencing technologies has revealed that genomic disorders and monogenic aetiologies contribute meaningfully to seemingly complex forms of CKD across different clinically defined subgroups and are characterized by high genetic and phenotypic heterogeneity. Investigations of prevalent genomic disorders in CKD have integrated genetic, bioinformatic and functional studies to pinpoint the genetic drivers underlying their renal and extra-renal manifestations, revealing both monogenic and polygenic mechanisms. Similarly, massively parallel sequencing-based analyses have identified gene- and allele-level variation that contribute to the clinically diverse phenotypes observed for many monogenic forms of nephropathy. Genome-wide sequencing studies suggest that dual genetic diagnoses are found in at least 5% of patients in whom a genetic cause of disease is identified, highlighting the fact that complex phenotypes can also arise from multilocus variation. A multifaceted approach that incorporates genetic and phenotypic data from large, diverse cohorts will help to elucidate the complex relationships between genotype and phenotype for different forms of CKD, supporting personalized medicine for individuals with kidney disease.
Collapse
Affiliation(s)
- Emily E Groopman
- Division of Nephrology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Gundula Povysil
- Institute for Genomic Medicine, Columbia University, New York, NY, USA
| | - David B Goldstein
- Institute for Genomic Medicine, Columbia University, New York, NY, USA
| | - Ali G Gharavi
- Division of Nephrology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
- Institute for Genomic Medicine, Columbia University, New York, NY, USA.
- Center for Precision Medicine and Genomics, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, USA.
| |
Collapse
|
4
|
Xu Z, Chen J, Yu W, Li X, Lin B, Lai D, Xu A, Tang Y. New COL4A5 mutation in IgA nephropathy. Postgrad Med J 2020; 98:13-17. [PMID: 33087535 DOI: 10.1136/postgradmedj-2020-138625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/09/2020] [Accepted: 10/03/2020] [Indexed: 01/24/2023]
Abstract
PURPOSE IgA nephropathy (IgAN) is the most common type of primary glomerulonephritis and a leading cause of chronic kidney disease (CKD) and end-stage kidney disease (ESKD). Recently, some case reports have shown that COL4A5 mutation is associated with IgAN. Here, we identified a new COL4A5 gene mutation in IgAN in a Chinese family. MATERIALS AND METHODS In the present study, the proband and his 23-year-old younger brother were both diagnosed with IgAN, manifested as haematuria, proteinuria and chronic kidney injury without hearing loss or ocular symptoms. Additionally, the proband's 30-year-old younger brother, also diagnosed with ESKD, had been undergoing dialysis for 2 years with normal hearing and eyesight. To exclude genetic disease, we conducted whole-exome sequencing and Sanger sequencing assays. RESULTS We found a new mutation in the COL4A5 gene (chrX:107 814 698, c.438+2->AAACCAATTATA-), a novel insertion mutation. Using vector transcription and Minigene transcriptional analyses, we verified, for the first time, the novel mutation pathogenicity of the COL4A5 gene. CONCLUSION Together with other published data, we suggest that genetic screening should be performed in IgAN, particularly for patients with a familial history. The effects of different mutated splice sites of the COL4A5 gene, as well as the tissue specificity of the splicing machinery contributing to the pathogenesis and prognosis of IgAN, remains unclear and warrants further exploration in the future.
Collapse
Affiliation(s)
- Zhenjian Xu
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Junzhe Chen
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.,Department of Nephrology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Wenjuan Yu
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.,Department of Nephrology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Xiaomei Li
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.,Department of Nephrology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Baojuan Lin
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.,Department of Nephrology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Deyuan Lai
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.,Department of Nephrology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Anping Xu
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.,Department of Nephrology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Ying Tang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China .,Department of Nephrology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| |
Collapse
|
5
|
Jacobs-Cachá C, Vergara A, García-Carro C, Agraz I, Toapanta-Gaibor N, Ariceta G, Moreso F, Serón D, López-Hellín J, Soler MJ. Challenges in primary focal segmental glomerulosclerosis diagnosis: from the diagnostic algorithm to novel biomarkers. Clin Kidney J 2020; 14:482-491. [PMID: 33623672 PMCID: PMC7886539 DOI: 10.1093/ckj/sfaa110] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 05/04/2020] [Indexed: 12/11/2022] Open
Abstract
Primary or idiopathic focal segmental glomerulosclerosis (FSGS) is a kidney entity that involves the podocytes, leading to heavy proteinuria and in many cases progresses to end-stage renal disease. Idiopathic FSGS has a bad prognosis, as it involves young individuals who, in a considerably high proportion (∼15%), are resistant to corticosteroids and other immunosuppressive treatments as well. Moreover, the disease recurs in 30–50% of patients after kidney transplantation, leading to graft function impairment. It is suspected that this relapsing disease is caused by a circulating factor(s) that would permeabilize the glomerular filtration barrier. However, the exact pathologic mechanism is an unsettled issue. Besides its poor outcome, a major concern of primary FSGS is the complexity to confirm the diagnosis, as it can be confused with other variants or secondary forms of FSGS and also with other glomerular diseases, such as minimal change disease. New efforts to optimize the diagnostic approach are arising to improve knowledge in well-defined primary FSGS cohorts of patients. Follow-up of properly classified primary FSGS patients will allow risk stratification for predicting the response to different treatments. In this review we will focus on the diagnostic algorithm used in idiopathic FSGS both in native kidneys and in disease recurrence after kidney transplantation. We will emphasize those potential confusing factors as well as their detection and prevention. In addition, we will also provide an overview of ongoing studies that recruit large cohorts of glomerulopathy patients (Nephrotic Syndrome Study Network and Cure Glomerulonephropathy, among others) and the experimental studies performed to find novel reliable biomarkers to detect primary FSGS.
Collapse
Affiliation(s)
- Conxita Jacobs-Cachá
- Nephrology Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain.,Department of Nephrology, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain.,Red de Investigaciones Renales (RedInRen), Madrid, Spain
| | - Ander Vergara
- Nephrology Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain.,Department of Nephrology, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain
| | - Clara García-Carro
- Nephrology Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain.,Department of Nephrology, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain.,Red de Investigaciones Renales (RedInRen), Madrid, Spain
| | - Irene Agraz
- Nephrology Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain.,Department of Nephrology, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain.,Red de Investigaciones Renales (RedInRen), Madrid, Spain
| | - Nestor Toapanta-Gaibor
- Nephrology Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain.,Department of Nephrology, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain
| | - Gema Ariceta
- Red de Investigaciones Renales (RedInRen), Madrid, Spain.,Department of Paediatric Nephrology, Hospital Universitari Vall d'Hebron. Universitat Autónoma de Barcelona, Barcelona, Spain
| | - Francesc Moreso
- Nephrology Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain.,Department of Nephrology, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain.,Red de Investigaciones Renales (RedInRen), Madrid, Spain
| | - Daniel Serón
- Nephrology Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain.,Department of Nephrology, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain.,Red de Investigaciones Renales (RedInRen), Madrid, Spain
| | - Joan López-Hellín
- Red de Investigaciones Renales (RedInRen), Madrid, Spain.,Department of Biochemistry, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain.,Biochemistry Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain
| | - Maria José Soler
- Nephrology Research Group, Vall d'hebrón Institut de Recerca (VHIR), Barcelona, Spain.,Department of Nephrology, Hospital Universitari Vall d'Hebron, Universitat Autónoma de Barcelona, Barcelona, Spain.,Red de Investigaciones Renales (RedInRen), Madrid, Spain
| |
Collapse
|
6
|
Cameron-Christie S, Wolock CJ, Groopman E, Petrovski S, Kamalakaran S, Povysil G, Vitsios D, Zhang M, Fleckner J, March RE, Gelfman S, Marasa M, Li Y, Sanna-Cherchi S, Kiryluk K, Allen AS, Fellström BC, Haefliger C, Platt A, Goldstein DB, Gharavi AG. Exome-Based Rare-Variant Analyses in CKD. J Am Soc Nephrol 2019; 30:1109-1122. [PMID: 31085678 DOI: 10.1681/asn.2018090909] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Accepted: 03/06/2019] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Studies have identified many common genetic associations that influence renal function and all-cause CKD, but these explain only a small fraction of variance in these traits. The contribution of rare variants has not been systematically examined. METHODS We performed exome sequencing of 3150 individuals, who collectively encompassed diverse CKD subtypes, and 9563 controls. To detect causal genes and evaluate the contribution of rare variants we used collapsing analysis, in which we compared the proportion of cases and controls carrying rare variants per gene. RESULTS The analyses captured five established monogenic causes of CKD: variants in PKD1, PKD2, and COL4A5 achieved study-wide significance, and we observed suggestive case enrichment for COL4A4 and COL4A3. Beyond known disease-associated genes, collapsing analyses incorporating regional variant intolerance identified suggestive dominant signals in CPT2 and several other candidate genes. Biallelic mutations in CPT2 cause carnitine palmitoyltransferase II deficiency, sometimes associated with rhabdomyolysis and acute renal injury. Genetic modifier analysis among cases with APOL1 risk genotypes identified a suggestive signal in AHDC1, implicated in Xia-Gibbs syndrome, which involves intellectual disability and other features. On the basis of the observed distribution of rare variants, we estimate that a two- to three-fold larger cohort would provide 80% power to implicate new genes for all-cause CKD. CONCLUSIONS This study demonstrates that rare-variant collapsing analyses can validate known genes and identify candidate genes and modifiers for kidney disease. In so doing, these findings provide a motivation for larger-scale investigation of rare-variant risk contributions across major clinical CKD categories.
Collapse
Affiliation(s)
- Sophia Cameron-Christie
- AstraZeneca Centre for Genomics Research, Discovery Sciences, R&D BioPharmaceuticals, AstraZeneca, Cambridge, UK
| | | | - Emily Groopman
- Division of Nephrology, Department of Medicine, Columbia University, New York, New York
| | - Slavé Petrovski
- AstraZeneca Centre for Genomics Research, Discovery Sciences, R&D BioPharmaceuticals, AstraZeneca, Cambridge, UK
| | | | - Gundula Povysil
- AstraZeneca Centre for Genomics Research, Discovery Sciences, R&D BioPharmaceuticals, AstraZeneca, Cambridge, UK.,Institute for Genomic Medicine, Columbia University Medical Center, New York, New York
| | - Dimitrios Vitsios
- AstraZeneca Centre for Genomics Research, Discovery Sciences, R&D BioPharmaceuticals, AstraZeneca, Cambridge, UK
| | - Mengqi Zhang
- Institute for Genomic Medicine, Columbia University Medical Center, New York, New York.,Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina; and
| | - Jan Fleckner
- AstraZeneca Centre for Genomics Research, Discovery Sciences, R&D BioPharmaceuticals, AstraZeneca, Cambridge, UK
| | - Ruth E March
- Precision Medicine, R&D Oncology, AstraZeneca, Cambridge, UK
| | | | - Maddalena Marasa
- Division of Nephrology, Department of Medicine, Columbia University, New York, New York
| | - Yifu Li
- Division of Nephrology, Department of Medicine, Columbia University, New York, New York
| | - Simone Sanna-Cherchi
- Division of Nephrology, Department of Medicine, Columbia University, New York, New York
| | - Krzysztof Kiryluk
- Division of Nephrology, Department of Medicine, Columbia University, New York, New York
| | - Andrew S Allen
- Institute for Genomic Medicine, Columbia University Medical Center, New York, New York.,Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina; and
| | - Bengt C Fellström
- Department of Medical Sciences, Uppsala University Hospital, Uppsala, Sweden; and
| | - Carolina Haefliger
- AstraZeneca Centre for Genomics Research, Discovery Sciences, R&D BioPharmaceuticals, AstraZeneca, Cambridge, UK
| | - Adam Platt
- AstraZeneca Centre for Genomics Research, Discovery Sciences, R&D BioPharmaceuticals, AstraZeneca, Cambridge, UK;
| | - David B Goldstein
- AstraZeneca Centre for Genomics Research, Discovery Sciences, R&D BioPharmaceuticals, AstraZeneca, Cambridge, UK; .,Department of Genetics and Development and.,Institute for Genomic Medicine, Columbia University Medical Center, New York, New York
| | - Ali G Gharavi
- Division of Nephrology, Department of Medicine, Columbia University, New York, New York; .,Institute for Genomic Medicine, Columbia University Medical Center, New York, New York
| |
Collapse
|
7
|
Stone H, Magella B, Bennett MR. The Search for Biomarkers to Aid in Diagnosis, Differentiation, and Prognosis of Childhood Idiopathic Nephrotic Syndrome. Front Pediatr 2019; 7:404. [PMID: 31681707 PMCID: PMC6805718 DOI: 10.3389/fped.2019.00404] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 09/18/2019] [Indexed: 12/13/2022] Open
Abstract
Identification of genes associated with childhood-onset nephrotic syndrome has significantly advanced our understanding of the pathogenesis of this complex disease over the past two decades, however the precise etiology in many cases remains unclear. At this time, we still rely on invasive kidney biopsy to determine the underlying cause of nephrotic syndrome in adults. In children, response to steroid therapy has been shown to be the best indicator of prognosis, and therefore all children are treated initially with corticosteroids. Because this strategy exposes a large number of children to the toxicities of steroids without providing any benefit, many researchers have sought to find a marker that could predict a patient's response to steroids at the time of diagnosis. Additionally, the identification of such a marker could provide prognostic information about a patient's response to medications, progression to end stage renal disease, and risk of disease recurrence following transplantation. Major advances have been made in understanding how genetic biomarkers can be used to predict a patient's response to therapies and disease course, especially after transplantation. Research attempting to identify urine- and serum-based biomarkers which could be used for the diagnosis, differentiation, and prognosis of nephrotic syndrome has become an area of emphasis. In this review, we explore the most exciting biomarkers and their potential clinical applications.
Collapse
Affiliation(s)
- Hillarey Stone
- Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Bliss Magella
- Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Michael R Bennett
- Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| |
Collapse
|
8
|
Tao J, Lieberman J, Lafayette RA, Kambham N. A rare case of Alport syndrome, atypical hemolytic uremic syndrome and Pauci-immune crescentic glomerulonephritis. BMC Nephrol 2018; 19:355. [PMID: 30541482 PMCID: PMC6291978 DOI: 10.1186/s12882-018-1170-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 12/03/2018] [Indexed: 11/24/2022] Open
Abstract
Background Renal thrombotic microangiopathy (TMA) is occasionally seen in biopsies with pauci-immune necrotizing crescentic glomerulonephritis (PCGN). Recent study indicated that the complement activation is more prominent in the ANCA-negative glomerulonephritis. Case presentation We report a case of concurrent TMA and PCGN without ANCA positivity. Interestingly, our patient also had biopsy features supportive of Alport syndrome (AS). Genetic studies identified variants and polymorphisms in alternative complement pathway genes that confer substantial risk of developing atypical hemolytic uremic syndrome (aHUS). Conclusions Abnormal activation in complement pathway may represent a common pathogenic link between these three distinct entities.
Collapse
Affiliation(s)
- Jianling Tao
- Department of Medicine, Division of Nephrology, Stanford University, Stanford, USA
| | | | - Richard A Lafayette
- Department of Medicine, Division of Nephrology, Stanford University, Stanford, USA
| | - Neeraja Kambham
- Department of Pathology, Stanford University, Stanford, CA, USA.
| |
Collapse
|
9
|
Gulati A, Somlo S. Whole exome sequencing: a state-of-the-art approach for defining (and exploring!) genetic landscapes in pediatric nephrology. Pediatr Nephrol 2018; 33:745-761. [PMID: 28660367 DOI: 10.1007/s00467-017-3698-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 05/04/2017] [Accepted: 05/09/2017] [Indexed: 12/30/2022]
Abstract
The genesis of whole exome sequencing as a powerful tool for detailing the protein coding sequence of the human genome was conceptualized based on the availability of next-generation sequencing technology and knowledge of the human reference genome. The field of pediatric nephrology enriched with molecularly unsolved phenotypes is allowing the clinical and research application of whole exome sequencing to enable novel gene discovery and provide amendment of phenotypic misclassification. Recent studies in the field have informed us that newer high-throughput sequencing techniques are likely to be of high yield when applied in conjunction with conventional genomic approaches such as linkage analysis and other strategies used to focus subsequent analysis. They have also emphasized the need for the validation of novel genetic findings in large collaborative cohorts and the production of robust corroborative biological data. The well-structured application of comprehensive genomic testing in clinical and research arenas will hopefully continue to advance patient care and precision medicine, but does call for attention to be paid to its integrated challenges.
Collapse
Affiliation(s)
- Ashima Gulati
- Division of Nephrology, Department of Pediatrics, Yale University School of Medicine, New Haven, CT, USA.
| | - Stefan Somlo
- Departments of Internal Medicine and Genetics, Yale University School of Medicine, New Haven, CT, USA
| |
Collapse
|
10
|
Abstract
Technologies such as next-generation sequencing and chromosomal microarray have advanced the understanding of the molecular pathogenesis of a variety of renal disorders. Genetic findings are increasingly used to inform the clinical management of many nephropathies, enabling targeted disease surveillance, choice of therapy, and family counselling. Genetic analysis has excellent diagnostic utility in paediatric nephrology, as illustrated by sequencing studies of patients with congenital anomalies of the kidney and urinary tract and steroid-resistant nephrotic syndrome. Although additional investigation is needed, pilot studies suggest that genetic testing can also provide similar diagnostic insight among adult patients. Reaching a genetic diagnosis first involves choosing the appropriate testing modality, as guided by the clinical presentation of the patient and the number of potential genes associated with the suspected nephropathy. Genome-wide sequencing increases diagnostic sensitivity relative to targeted panels, but holds the challenges of identifying causal variants in the vast amount of data generated and interpreting secondary findings. In order to realize the promise of genomic medicine for kidney disease, many technical, logistical, and ethical questions that accompany the implementation of genetic testing in nephrology must be addressed. The creation of evidence-based guidelines for the utilization and implementation of genetic testing in nephrology will help to translate genetic knowledge into improved clinical outcomes for patients with kidney disease.
Collapse
Affiliation(s)
- Emily E Groopman
- Division of Nephrology, Columbia University College of Physicians and Surgeons, 1150 Saint Nicholas Avenue, Russ Berrie Pavilion #412C, New York, New York 10032, USA
| | - Hila Milo Rasouly
- Division of Nephrology, Columbia University College of Physicians and Surgeons, 1150 Saint Nicholas Avenue, Russ Berrie Pavilion #412C, New York, New York 10032, USA
| | - Ali G Gharavi
- Division of Nephrology, Columbia University College of Physicians and Surgeons, 1150 Saint Nicholas Avenue, Russ Berrie Pavilion #412C, New York, New York 10032, USA
| |
Collapse
|
11
|
Barua M, John R, Stella L, Li W, Roslin NM, Sharif B, Hack S, Lajoie-Starkell G, Schwaderer AL, Becknell B, Wuttke M, Köttgen A, Cattran D, Paterson AD, Pei Y. X-Linked Glomerulopathy Due to COL4A5 Founder Variant. Am J Kidney Dis 2017; 71:441-445. [PMID: 29198386 DOI: 10.1053/j.ajkd.2017.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 09/01/2017] [Indexed: 12/30/2022]
Abstract
Alport syndrome is a rare hereditary disorder caused by rare variants in 1 of 3 genes encoding for type IV collagen. Rare variants in COL4A5 on chromosome Xq22 cause X-linked Alport syndrome, which accounts for ∼80% of the cases. Alport syndrome has a variable clinical presentation, including progressive kidney failure, hearing loss, and ocular defects. Exome sequencing performed in 2 affected related males with an undefined X-linked glomerulopathy characterized by global and segmental glomerulosclerosis, mesangial hypercellularity, and vague basement membrane immune complex deposition revealed a COL4A5 sequence variant, a substitution of a thymine by a guanine at nucleotide 665 (c.T665G; rs281874761) of the coding DNA predicted to lead to a cysteine to phenylalanine substitution at amino acid 222, which was not seen in databases cataloguing natural human genetic variation, including dbSNP138, 1000 Genomes Project release version 01-11-2004, Exome Sequencing Project 21-06-2014, or ExAC 01-11-2014. Review of the literature identified 2 additional families with the same COL4A5 variant leading to similar atypical histopathologic features, suggesting a unique pathologic mechanism initiated by this specific rare variant. Homology modeling suggests that the substitution alters the structural and dynamic properties of the type IV collagen trimer. Genetic analysis comparing members of the 3 families indicated a distant relationship with a shared haplotype, implying a founder effect.
Collapse
Affiliation(s)
- Moumita Barua
- Division of Nephrology, University Health Network, Toronto, Canada; Toronto General Research Institute, Toronto General Hospital, Toronto, Canada; Department of Medicine, University of Toronto, Toronto, Canada; Institute of Medical Sciences, University of Toronto, Toronto, Canada.
| | - Rohan John
- Department of Pathology, University Health Network, Toronto, Canada
| | - Lorenzo Stella
- Department of Chemical Sciences and Technologies, University of Rome Tor Vergata, Rome, Italy
| | - Weili Li
- The Centre for Applied Genomics, Hospital for Sick Children's, Brampton, Canada
| | - Nicole M Roslin
- The Centre for Applied Genomics, Hospital for Sick Children's, Brampton, Canada
| | - Bedra Sharif
- Division of Nephrology, University Health Network, Toronto, Canada
| | - Saidah Hack
- Division of Nephrology, University Health Network, Toronto, Canada
| | - Ginette Lajoie-Starkell
- William Osler Health System, Brampton, Canada; Department of Pathobiology and Laboratory Medicine, University of Toronto, Toronto, Canada
| | - Andrew L Schwaderer
- Nephrology Section, Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics, Ohio State University Center for Clinical and Translational Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH
| | - Brian Becknell
- Nephrology Section, Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics, Ohio State University Center for Clinical and Translational Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH
| | - Matthias Wuttke
- Institute of Genetic Epidemiology, Medical Center and Faculty of Medicine - University of Freiburg, Freiburg, Germany; Division of Nephrology, University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Anna Köttgen
- Institute of Genetic Epidemiology, Medical Center and Faculty of Medicine - University of Freiburg, Freiburg, Germany; Division of Nephrology, University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Daniel Cattran
- Division of Nephrology, University Health Network, Toronto, Canada; Toronto General Research Institute, Toronto General Hospital, Toronto, Canada; Department of Medicine, University of Toronto, Toronto, Canada
| | - Andrew D Paterson
- Institute of Medical Sciences, University of Toronto, Toronto, Canada; The Centre for Applied Genomics, Hospital for Sick Children's, Brampton, Canada; Epidemiology & Biostatistics, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada
| | - York Pei
- Division of Nephrology, University Health Network, Toronto, Canada; Toronto General Research Institute, Toronto General Hospital, Toronto, Canada; Department of Medicine, University of Toronto, Toronto, Canada; Institute of Medical Sciences, University of Toronto, Toronto, Canada
| |
Collapse
|
12
|
Sanchez-Niño MD, Ortiz A. Thrombotic microangiopathy: expanding genetic, clinical and therapeutic spectra and the need for worldwide implementation of recent advances. Clin Kidney J 2015; 8:686-9. [PMID: 26613024 PMCID: PMC4655809 DOI: 10.1093/ckj/sfv115] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2015] [Indexed: 02/07/2023] Open
Abstract
In this issue of CKJ, four reports address different aspects of a rare condition, thrombotic microangiopathy, including atypical haemolytic uraemic syndrome. For rare diseases, a single case report may provide hypothesis-generating information that may lead to concept-changing research with the potential to influence patient care. The present reports and small series illustrate the following aspects of thrombotic microangiopathy: (i) the role of whole-exome sequencing and of repeating the family history assessment over time in reducing the number of chronic kidney disease patients with non-specific diagnosis (e.g. focal segmental glomerulosclerosis without any further indication as to aetiology or hypertension-attributed kidney disease) and the need for further studies on the potential for type IV collagen mutations to be associated with thrombotic microangiopathy, i.e. the potential for an expanding genetic spectrum; (ii) the expanding clinical spectrum from an acute catastrophic disease to a chronic, mild, stable condition with unknown long-term consequences and uncharted therapeutic approaches; (iii) the expanding therapeutic spectrum, with the successful use of eculizumab to treat thrombotic microangiopathy in the context of overlap autoimmune disease and (iv) the huge worldwide inequalities in the implementation of these and other advances. International collaboration is needed to address these issues and should encompass the wider use of already available registries for this rare disease and the worldwide implementation of current effective, yet expensive, therapies.
Collapse
Affiliation(s)
- Maria D Sanchez-Niño
- IIS-Fundacion Jimenez Diaz, School of Medicine, Universidad Autonoma de Madrid; Fundacion Renal Iñigo Alvarez de Toledo-IRSIN and REDINREN , Madrid , Spain
| | - Alberto Ortiz
- IIS-Fundacion Jimenez Diaz, School of Medicine, Universidad Autonoma de Madrid; Fundacion Renal Iñigo Alvarez de Toledo-IRSIN and REDINREN , Madrid , Spain
| |
Collapse
|