RESUMO
While 44-83% of children with steroid-resistant nephrotic syndrome (SRNS) without a proven genetic cause respond to treatment with a calcineurin inhibitor (CNI), current guidelines recommend against the use of immunosuppression in monogenic SRNS. This is despite existing evidence suggesting that remission with CNI treatment is possible and can improve prognosis in some cases of monogenic SRNS. Herein, our retrospective study assessed response frequency, predictors of response and kidney function outcomes among children with monogenic SRNS treated with a CNI for at least three months. Data from 203 cases (age 0-18 years) were collected from 37 pediatric nephrology centers. Variant pathogenicity was reviewed by a geneticist, and 122 patients with a pathogenic and 19 with a possible pathogenic genotype were included in the analysis. After six months of treatment and at last visit, 27.6% and 22.5% of all patients respectively, demonstrated partial or full response. Achievement of at least partial response at six months of treatment conferred a significant reduction in kidney failure risk at last follow-up compared to no response (hazard ratio [95% confidence interval] 0.25, [0.10-0.62]). Moreover, risk of kidney failure was significantly lower when only those with a follow-up longer than two years were considered (hazard ratio 0.35, [0.14-0.91]). Higher serum albumin level at CNI initiation was the only factor related to increased likelihood of significant remission at six months (odds ratio [95% confidence interval] 1.16, [1.08-1.24]). Thus, our findings justify a treatment trial with a CNI also in children with monogenic SRNS.
Assuntos
Síndrome Nefrótica , Podócitos , Insuficiência Renal , Criança , Humanos , Recém-Nascido , Lactente , Pré-Escolar , Adolescente , Síndrome Nefrótica/tratamento farmacológico , Síndrome Nefrótica/genética , Síndrome Nefrótica/patologia , Inibidores de Calcineurina/efeitos adversos , Imunossupressores/efeitos adversos , Estudos Retrospectivos , Podócitos/patologia , Insuficiência Renal/induzido quimicamenteRESUMO
BACKGROUND: COVID-19 disease in kidney transplant (KT) recipients is associated with increased morbidity, mortality, and hospitalization rates. Unfortunately, KT recipients also have a reduced response to SARS-CoV-2 immunization. The primary aim of this study was to assess immunologic response to SARS-CoV-2 mRNA vaccines in pediatric kidney transplant recipients 12-18 years of age. Secondary aims were to assess response rates following a third immunization and determine factors that influence immunization response. METHODS: Pediatric KT recipients in a single tertiary center received SARS-CoV-2 mRNA vaccination as per local protocol. SARS-CoV-2 immunoglobulin (IgG) was measured following second and/or third vaccination. Demographics including patient factors (age, gender, and underlying disease), transplant factors (time and type of transplant), and immunosuppression (induction, maintenance, and immunomodulatory therapies such as IVIG) were collected from the medical records. RESULTS: Of 20 participants, 10 (50%) responded following a two-dose vaccine schedule, which increased to 15 (75%) after three doses. Maintenance immunosuppression affected immunologic response, with azathioprine demonstrating a higher rate of response to vaccine compared to mycophenolate (100% vs. 38%, p = 0.04). Increasing prednisolone dose had a negative impact on immunologic response (0.01 mg/kg/day increase: OR 1.60 95% CI 1.01 to 2.57). Tacrolimus dose and trough levels, age, time post-transplant, underlying disease, and other immunosuppression did not impact immunologic response. CONCLUSIONS: Pediatric KT recipients had similar response rates following SARS-CoV-2 immunization as adult KT recipients. Immunologic response improved following a third immunization. Choice of antimetabolite and prednisolone dosing influenced the rate of response. A higher resolution version of the Graphical abstract is available as Supplementary Information.
Assuntos
COVID-19 , Transplante de Rim , Adulto , Humanos , Criança , SARS-CoV-2 , Transplante de Rim/efeitos adversos , COVID-19/prevenção & controle , Vacinação , Transplantados , Imunossupressores/efeitos adversos , RNA Mensageiro , Anticorpos AntiviraisRESUMO
BACKGROUND: Children with chronic kidney disease (CKD) require multidisciplinary care to meet their complex healthcare needs. Patient navigators are trained non-medical personnel who assist patients and caregivers to overcome barriers to accessing health services through care coordination. This trial aims to determine the effectiveness of a patient navigator program in children with CKD. METHODS: The NAVKIDS2 trial is a multi-center, waitlisted, randomized controlled trial of patient navigators in children with CKD conducted at five sites across Australia. Children (0-16 years) with CKD from low socioeconomic status rural or remote areas were randomized to an intervention group or a waitlisted control group (to receive intervention after 6 months). The study primary and secondary endpoints include the self-rated health (SRH) (primary), and utility-based quality of life, progression of kidney dysfunction of the child, SRH, and satisfaction with healthcare of the caregiver at 6 months post-randomization. RESULTS: The trial completed recruitment in October 2021 with expected completion of follow-up by October 2022. There were 162 patients enrolled with 80 and 82 patients randomized to the immediate intervention and waitlisted groups, respectively. Fifty-eight (36%) participants were from regional/remote areas, with a median (IQR) age of 9.5 (5.0, 13.0) years, 46% were of European Australian ethnicity, and 65% were male. A total of 109 children (67%) had CKD stages 1-5, 42 (26%) were transplant recipients, and 11 (7%) were receiving dialysis. CONCLUSION: The NAVKIDS2 trial is designed to evaluate the effectiveness of patient navigation in children with CKD from families experiencing socioeconomic disadvantage. A higher resolution version of the Graphical abstract is available as Supplementary information.
Assuntos
Navegação de Pacientes , Insuficiência Renal Crônica , Humanos , Masculino , Criança , Feminino , Qualidade de Vida , Diálise Renal , Austrália , Insuficiência Renal Crônica/terapiaRESUMO
AIM: The purpose of this study was to evaluate whether pre-recorded video-based lectures (VBLs) covering a range of paediatric topics are an acceptable means of providing ongoing education for consultant and trainee paediatricians in Australia. METHODS: Previous participants (paediatric consultants and junior medical officers) of a neurology outreach teleconference programme offered by a paediatric neurologist between 2017 and 2020 were invited to participate in a multi-specialty pre-recorded video-based education programme. Acceptability was explored by assessing relevance, likelihood of utilising VBL's in the future, uptake and learning activity preferences. The impact of VBLs on confidence, currency and practice was also explored. Additional data including topics of interest, preferred video format, duration, viewing method and frequency of delivery were captured, to better understand participant preferences to inform future efforts. RESULTS: A total of 135 consented; 116 returned baseline; 94 returned follow-up surveys. Preferred learning activities included a live/interactive component. Videos were considered relevant. Preferences for pre-recorded videos improved from ninth to sixth most preferred learning activity post-intervention. VBL convenience and accessibility were valued. Practice was altered in: approach to management, use of treatments, confidence in decision-making, and discussion with families and patients. The average view duration was 16 min. Longer videos yielded slightly lower audience retention rates. For future offerings, the majority endorsed a preference for a 'mixed' video format and duration of 20-40 min, offered monthly. CONCLUSION: Video-based medical education is an appealing and sustainable alternative, given the convenience of unrestricted accessibility, in meeting ongoing learning needs of Australian paediatricians and trainees.
Assuntos
Pessoal de Saúde , Aprendizagem , Humanos , Criança , Austrália , Pessoal de Saúde/educação , Inquéritos e Questionários , PediatrasRESUMO
BACKGROUND: The cytokine IL-33 is an activator of innate lymphoid cells 2 (ILC2s) in innate immunity and allergic inflammation. B cell activating factor (BAFF) plays a central role in B cell proliferation and differentiation, and high levels of this protein cause excess antibody production, including IgA. BAFF-transgenic mice overexpress BAFF and spontaneously develop glomerulonephritis that resembles human IgA nephropathy. METHODS: We administered IL-33 or PBS to wild-type and BAFF-transgenic mice. After treating Rag1-deficient mice with IL-33, with or without anti-CD90.2 to preferentially deplete ILC2s, we isolated splenocytes, which were adoptively transferred into BAFF-transgenic mice. RESULTS: BAFF-transgenic mice treated with IL-33 developed more severe kidney dysfunction and proteinuria, glomerular sclerosis, tubulointerstitial damage, and glomerular deposition of IgA and C3. Compared with wild-type mice, BAFF-transgenic mice exhibited increases of CD19+ B cells in spleen and kidney and ILC2s in kidney and intestine, which were further increased by administration of IL-33. Administering IL-33 to wild-type mice had no effect on kidney function or histology, nor did it alter the number of ILC2s in spleen, kidney, or intestine. To understand the role of ILC2s, splenocytes were transferred from IL-33-treated Rag1-deficient mice into BAFF-transgenic mice. Glomerulonephritis and IgA deposition were exacerbated by transfer of IL-33-stimulated Rag1-deficient splenocytes, but not by ILC2 (anti-CD90.2)-depleted splenocytes. Wild-type mice infused with IL-33-treated Rag1-deficient splenocytes showed no change in kidney function or ILC2 numbers or distribution. CONCLUSIONS: IL-33-expanded ILC2s exacerbated IgA glomerulonephritis in a mouse model. These findings indicate that IL-33 and ILC2s warrant evaluation as possible mediators of human IgA nephropathy.
Assuntos
Glomerulonefrite por IGA , Interleucina-33 , Animais , Fator Ativador de Células B , Feminino , Proteínas de Homeodomínio/genética , Humanos , Imunidade Inata , Imunoglobulina A , Interleucina-4 , Linfócitos , Masculino , Camundongos , Camundongos TransgênicosRESUMO
BACKGROUND: Variants in genes encoding nuclear pore complex (NPC) proteins are a newly identified cause of paediatric steroid-resistant nephrotic syndrome (SRNS). Recent reports describing NUP93 variants suggest these could be a significant cause of paediatric onset SRNS. We report NUP93 cases in the UK and demonstrate in vivo functional effects of Nup93 depletion in a fly (Drosophila melanogaster) nephrocyte model. METHODS: Three hundred thirty-seven paediatric SRNS patients from the National cohort of patients with Nephrotic Syndrome (NephroS) were whole exome and/or whole genome sequenced. Patients were screened for over 70 genes known to be associated with Nephrotic Syndrome (NS). D. melanogaster Nup93 knockdown was achieved by RNA interference using nephrocyte-restricted drivers. RESULTS: Six novel homozygous and compound heterozygous NUP93 variants were detected in 3 sporadic and 2 familial paediatric onset SRNS characterised histologically by focal segmental glomerulosclerosis (FSGS) and progressing to kidney failure by 12 months from clinical diagnosis. Silencing of the two orthologs of human NUP93 expressed in D. melanogaster, Nup93-1, and Nup93-2 resulted in significant signal reduction of up to 82% in adult pericardial nephrocytes with concomitant disruption of NPC protein expression. Additionally, nephrocyte morphology was highly abnormal in Nup93-1 and Nup93-2 silenced flies surviving to adulthood. CONCLUSION: We expand the spectrum of NUP93 variants detected in paediatric onset SRNS and demonstrate its incidence within a national cohort. Silencing of either D. melanogaster Nup93 ortholog caused a severe nephrocyte phenotype, signaling an important role for the nucleoporin complex in podocyte biology. A higher resolution version of the Graphical abstract is available as Supplementary information.
Assuntos
Drosophila melanogaster , Síndrome Nefrótica , Complexo de Proteínas Formadoras de Poros Nucleares , Podócitos , Adulto , Animais , Criança , Modelos Animais de Doenças , Drosophila melanogaster/genética , Resistência a Medicamentos/genética , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Síndrome Nefrótica/tratamento farmacológico , Síndrome Nefrótica/genética , Síndrome Nefrótica/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Podócitos/metabolismoRESUMO
Patients with chronic kidney disease are required to make difficult decisions, negotiating between the risks, burdens and benefits for any proposed course. This process can be extremely challenging, since these decisions involve inherent risks, which can impact on survival and quality of life. Shared decision-making offers a patient-centred approach in partnering with patients to make decisions about their treatment, which reflect their values and preferences. Shared decision-making can improve patient preparedness, motivation, satisfaction, and adherence to the treatment or decision agreed upon. In this review article, we outline the key principles of shared decision-making, and provide a framework with communication strategies to facilitate shared decision-making. We highlight the broad range and context of decisions faced by patients in several areas of nephrology care and discuss patient-important outcomes, priorities and motivations that underpin their decision-making. Preserving patient autonomy through shared decision-making ensures close consideration of patient preferences to enhance satisfaction with the decision reached and optimize outcomes important to patients.
Assuntos
Tomada de Decisão Compartilhada , Nefrologistas , Nefrologia , Participação do Paciente , Assistência Centrada no Paciente , Insuficiência Renal Crônica/terapia , Atitude do Pessoal de Saúde , Técnicas de Apoio para a Decisão , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Preferência do Paciente , Relações Médico-Paciente , Insuficiência Renal Crônica/diagnósticoRESUMO
AIM: To investigate and describe factors contributing to the impact of caring for a child with posterior urethral valves and to determine the extent to which families view their care as family-centred, and whether this can affect the impact of care. METHODS: A cross-sectional, survey-based study involving primary caregivers of children with posterior urethral valves. Caregivers completed the Impact on Family Scale (IOFS) and the Measure of Processes of Care (MPOC). Regression analyses were used to assess the relationship between child-related variables, demographic variables, MPOC and IOFS scores. RESULTS: Thirty-one primary caregivers completed both questionnaires. Caregivers of children with moderate/severe chronic kidney disease (CKD) scored higher on the IOFS compared to those caring for children with mild CKD. Caregivers rated care received highly but reported lower scores in subscales related to information provision. Receiving less respectful and supportive care was significantly associated with lower IOFS scores. CONCLUSION: The impact of caring for a child with posterior urethral valves is variable and is strongly determined by the severity of the associated CKD. Further research is required to show whether improving family centredness of care can reduce the impact of caring for children with posterior urethral valves.
Assuntos
Serviços de Saúde da Criança , Cuidadores , Criança , Estudos Transversais , Humanos , Relações Profissional-Família , Inquéritos e QuestionáriosRESUMO
Nephrotic syndrome (NS), the association of gross proteinuria, hypoalbuminaemia, edema, and hyperlipidemia, can be clinically divided into steroid-sensitive (SSNS) and steroid-resistant (SRNS) forms. SRNS regularly progresses to end-stage renal failure. By homozygosity mapping and whole exome sequencing, we here identify recessive mutations in Crumbs homolog 2 (CRB2) in four different families affected by SRNS. Previously, we established a requirement for zebrafish crb2b, a conserved regulator of epithelial polarity, in podocyte morphogenesis. By characterization of a loss-of-function mutation in zebrafish crb2b, we now show that zebrafish crb2b is required for podocyte foot process arborization, slit diaphragm formation, and proper nephrin trafficking. Furthermore, by complementation experiments in zebrafish, we demonstrate that CRB2 mutations result in loss of function and therefore constitute causative mutations leading to NS in humans. These results implicate defects in podocyte apico-basal polarity in the pathogenesis of NS.
Assuntos
Proteínas de Transporte/genética , Proteínas de Membrana/genética , Síndrome Nefrótica/genética , Sequência de Aminoácidos , Animais , Proteínas de Transporte/metabolismo , Criança , Pré-Escolar , Mapeamento Cromossômico , Exoma , Genes Recessivos , Homozigoto , Humanos , Lactente , Falência Renal Crônica/etiologia , Falência Renal Crônica/genética , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Mutação , Síndrome Nefrótica/complicações , Podócitos , Ratos , Peixe-Zebra/genéticaRESUMO
Steroid-resistant nephrotic syndrome (SRNS), a heterogeneous disorder of the renal glomerular filtration barrier, results in impairment of glomerular permselectivity. Inheritance of genetic SRNS may be autosomal dominant or recessive, with a subset of autosomal recessive SRNS presenting as congenital nephrotic syndrome (CNS). Mutations in 53 genes are associated with human SRNS, but these mutations explain ≤30% of patients with hereditary cases and only 20% of patients with sporadic cases. The proteins encoded by these genes are expressed in podocytes, and malfunction of these proteins leads to a universal end point of podocyte injury, glomerular filtration barrier disruption, and SRNS. Here, we identified novel disease-causing mutations in membrane-associated guanylate kinase, WW, and PDZ domain-containing 2 (MAGI2) through whole-exome sequencing of a deeply phenotyped cohort of patients with congenital, childhood-onset SRNS. Although MAGI2 has been shown to interact with nephrin and regulate podocyte cytoskeleton and slit diaphragm dynamics, MAGI2 mutations have not been described in human SRNS. We detected two unique frameshift mutations and one duplication in three patients (two families); two siblings shared the same homozygous frameshift mutation, whereas one individual with sporadic SRNS exhibited compound heterozygosity. Two mutations were predicted to introduce premature stop codons, and one was predicted to result in read through of the normal translational termination codon. Immunohistochemistry in kidney sections from these patients revealed that mutations resulted in lack of or diminished podocyte MAGI2 expression. Our data support the finding that mutations in the MAGI2 gene are causal for congenital SRNS.
Assuntos
Proteínas de Transporte/genética , Mutação , Síndrome Nefrótica/congênito , Proteínas Adaptadoras de Transdução de Sinal , Feminino , Guanilato Quinases , Humanos , Lactente , Masculino , Síndrome Nefrótica/genéticaRESUMO
Inherited kidney disease encompasses a broad range of disorders, with both multiple genes contributing to specific phenotypes and single gene defects having multiple clinical presentations. Advances in sequencing capacity may allow a genetic diagnosis for familial renal disease, by testing the increasing number of known causative genes. However, there has been limited translation of research findings of causative genes into clinical settings. Here, we report the results of a national accredited diagnostic genetic service for familial renal disease. An expert multidisciplinary team developed a targeted exomic sequencing approach with ten curated multigene panels (207 genes) and variant assessment individualized to the patient's phenotype. A genetic diagnosis (pathogenic genetic variant[s]) was identified in 58 of 135 families referred in two years. The genetic diagnosis rate was similar between families with a pediatric versus adult proband (46% vs 40%), although significant differences were found in certain panels such as atypical hemolytic uremic syndrome (88% vs 17%). High diagnostic rates were found for Alport syndrome (22 of 27) and tubular disorders (8 of 10), whereas the monogenic diagnostic rate for congenital anomalies of the kidney and urinary tract was one of 13. Quality reporting was aided by a strong clinical renal and genetic multidisciplinary committee review. Importantly, for a diagnostic service, few variants of uncertain significance were found with this targeted, phenotype-based approach. Thus, use of targeted massively parallel sequencing approaches in inherited kidney disease has a significant capacity to diagnose the underlying genetic disorder across most renal phenotypes.
Assuntos
Exoma/genética , Testes Genéticos/métodos , Nefropatias/diagnóstico , Adolescente , Adulto , Idoso , Austrália , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Aconselhamento Genético/métodos , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Lactente , Recém-Nascido , Nefropatias/genética , Nefropatias/terapia , Masculino , Pessoa de Meia-Idade , Fenótipo , Medicina de Precisão/métodos , Análise de Sequência de DNA , Adulto JovemRESUMO
Steroid Resistant Nephrotic Syndrome (SRNS) in children and young adults has differing etiologies with monogenic disease accounting for 2.9-30% in selected series. Using whole exome sequencing we sought to stratify a national population of children with SRNS into monogenic and non-monogenic forms, and further define those groups by detailed phenotypic analysis. Pediatric patients with SRNS were identified via a national United Kingdom Renal Registry. Whole exome sequencing was performed on 187 patients, of which 12% have a positive family history with a focus on the 53 genes currently known to be associated with nephrotic syndrome. Genetic findings were correlated with individual case disease characteristics. Disease causing variants were detected in 26.2% of patients. Most often this occurred in the three most common SRNS-associated genes: NPHS1, NPHS2, and WT1 but also in 14 other genes. The genotype did not always correlate with expected phenotype since mutations in OCRL, COL4A3, and DGKE associated with specific syndromes were detected in patients with isolated renal disease. Analysis by primary/presumed compared with secondary steroid resistance found 30.8% monogenic disease in primary compared with none in secondary SRNS permitting further mechanistic stratification. Genetic SRNS progressed faster to end stage renal failure, with no documented disease recurrence post-transplantation within this cohort. Primary steroid resistance in which no gene mutation was identified had a 47.8% risk of recurrence. In this unbiased pediatric population, whole exome sequencing allowed screening of all current candidate genes. Thus, deep phenotyping combined with whole exome sequencing is an effective tool for early identification of SRNS etiology, yielding an evidence-based algorithm for clinical management.
Assuntos
Genômica/métodos , Mutação , Síndrome Nefrótica/congênito , Medicina de Precisão , Adolescente , Idade de Início , Criança , Pré-Escolar , Estudos de Coortes , Progressão da Doença , Exoma , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Hereditariedade , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intracelular/genética , Estimativa de Kaplan-Meier , Rim/patologia , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/genética , Falência Renal Crônica/terapia , Masculino , Proteínas de Membrana/genética , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/genética , Síndrome Nefrótica/terapia , Linhagem , Fenótipo , Valor Preditivo dos Testes , Prognóstico , Sistema de Registros , Fatores de Risco , Reino Unido , Proteínas WT1/genética , Adulto JovemRESUMO
BACKGROUND: Genetic renal diseases (GRD) are a heterogeneous and incompletely understood group of disorders accounting for approximately 10 % of those diagnosed with kidney disease. The advent of Next Generation sequencing and new approaches to disease modelling may allow the identification and validation of novel genetic variants in patients with previously incompletely explained or understood GRD. METHODS/DESIGN: This study will recruit participants in families/trios from a multidisciplinary sub-specialty Renal Genetics Clinic where known genetic causes of GRD have been excluded or where genetic testing is not available. After informed patient consent, whole exome and/or genome sequencing will be performed with bioinformatics analysis undertaken using a customised variant assessment tool. A rigorous process for participant data management will be undertaken. Novel genetic findings will be validated using patient-derived induced pluripotent stem cells via differentiation to renal and relevant extra-renal tissue phenotypes in vitro. A process for managing the risk of incidental findings and the return of study results to participants has been developed. DISCUSSION: This investigator-initiated approach brings together experts in nephrology, clinical and molecular genetics, pathology and developmental biology to discover and validate novel genetic causes for patients in Australia affected by GRD without a known genetic aetiology or pathobiology.
Assuntos
Nefropatias/genética , Humanos , Projetos de Pesquisa , Estudos de Validação como AssuntoRESUMO
Of children with idiopathic nephrotic syndrome, 10%-20% fail to respond to steroids or develop secondary steroid resistance (termed initial steroid sensitivity) and the majority progress to transplantation. Although 30%-50% of these patients suffer disease recurrence after transplantation, with poor long-term outcome, no reliable indicator of recurrence has yet been identified. Notably, the incidence of recurrence after transplantation appears reduced in patients with steroid-resistant nephrotic syndrome (SRNS) due to monogenic disorders. We reviewed 150 transplanted patients with SRNS to identify biomarkers that consistently predict outcome of SRNS after transplantation. In all, 25 children had genetic or familial SRNS and did not experience post-transplant recurrence. We reviewed phenotypic factors, including initial steroid sensitivity, donor type, age, ethnicity, time to ESRD, and time on dialysis, in the remaining 125 children. Of these patients, 57 (45.6%) developed post-transplant recurrence; 26 of 28 (92.9%) patients with initial steroid sensitivity recurred after transplantation, whereas only 26 of 86 (30.2%) patients resistant from the outset recurred (odds ratio, 30; 95% confidence interval, 6.62 to 135.86; P<0.001). We were unable to determine recurrence in two patients (one with initial steroid sensitivity), and nine patients did not receive initial steroids. Our data show that initial steroid sensitivity is highly predictive of post-transplant disease recurrence in this pediatric patient population. Because a pathogenic circulating permeability factor in nephrotic syndrome remains to be confirmed, we propose initial steroid sensitivity as a surrogate marker for post-transplant recurrence.
Assuntos
Falência Renal Crônica/tratamento farmacológico , Falência Renal Crônica/cirurgia , Transplante de Rim , Síndrome Nefrótica/tratamento farmacológico , Síndrome Nefrótica/cirurgia , Esteroides/uso terapêutico , Adolescente , Distribuição por Idade , Idade de Início , Biomarcadores/metabolismo , Criança , Pré-Escolar , Resistência a Medicamentos , Feminino , Humanos , Lactente , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/genética , Masculino , Síndrome Nefrótica/epidemiologia , Síndrome Nefrótica/genética , Recidiva , Diálise Renal , Fatores de Risco , TranscriptomaRESUMO
Focal segmental glomerulosclerosis (FSGS) is associated with glomerular podocyte injury. Podocytes undergo dramatic changes in their actin structure, with little mechanistic insight to date into the human disease. Post-transplantation recurrence of FSGS is the archetypal form of the disease caused by unknown circulating plasma 'factors'. There is increasing indication that plasma protease activity could be central to this disease. Using clinical plasma exchange material, collected from patients in relapse and remission stages of disease, the effects of FSGS plasma on human conditionally immortalized podocytes (ciPods) were studied. We show that vasodilator stimulated phosphoprotein (VASP) is phosphorylated in response to relapse plasma from ten consecutively tested patients, and not in response to paired remission plasma or non-FSGS controls. The phosphorylation signal is absent in human podocytes carrying a pathological podocin mutation. To test for a plasma ligand, inhibition of proteases in relapse plasma leads to the loss of VASP phosphorylation. By the use of siRNA technology, we show that proteases in the plasma signal predominantly via protease activated receptor-1 (PAR1) to VASP. Mechanistically, FSGS plasma increases podocyte motility, which is dependent on VASP phosphorylation. These data suggest a specific biomarker for disease activity, as well as revealing a novel and highly specific receptor-mediated signalling pathway to the actin cytoskeleton.
Assuntos
Moléculas de Adesão Celular/metabolismo , Glomerulosclerose Segmentar e Focal/enzimologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Nefrose/enzimologia , Peptídeo Hidrolases/sangue , Fosfoproteínas/metabolismo , Podócitos/enzimologia , Receptor PAR-1/metabolismo , Citoesqueleto de Actina/enzimologia , Adolescente , Adulto , Linhagem Celular , Movimento Celular , Criança , Pré-Escolar , Feminino , Glomerulosclerose Segmentar e Focal/sangue , Glomerulosclerose Segmentar e Focal/genética , Glomerulosclerose Segmentar e Focal/terapia , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Mutação , Nefrose/sangue , Nefrose/genética , Nefrose/terapia , Fosforilação , Troca Plasmática , Podócitos/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Interferência de RNA , Receptor PAR-1/efeitos dos fármacos , Receptor PAR-1/genética , Recidiva , Indução de Remissão , Transdução de Sinais , Fatores de Tempo , Transfecção , Resultado do TratamentoRESUMO
BACKGROUND: Truncating variants in desmoplakin (DSPtv) are an important cause of arrhythmogenic cardiomyopathy; however the genetic architecture and genotype-specific risk factors are incompletely understood. We evaluated phenotype, risk factors for ventricular arrhythmias, and underlying genetics of DSPtv cardiomyopathy. METHODS: Individuals with DSPtv and any cardiac phenotype, and their gene-positive family members were included from multiple international centers. Clinical data and family history information were collected. Event-free survival from ventricular arrhythmia was assessed. Variant location was compared between cases and controls, and literature review of reported DSPtv performed. RESULTS: There were 98 probands and 72 family members (mean age at diagnosis 43±8 years, 59% women) with a DSPtv, of which 146 were considered clinically affected. Ventricular arrhythmia (sudden cardiac arrest, sustained ventricular tachycardia, appropriate implantable cardioverter defibrillator therapy) occurred in 56 (33%) individuals. DSPtv location and proband status were independent risk factors for ventricular arrhythmia. Further, gene region was important with variants in cases (cohort n=98; Clinvar n=167) more likely to occur in the regions resulting in nonsense mediated decay of both major DSP isoforms, compared with n=124 genome aggregation database control variants (148 [83.6%] versus 29 [16.4%]; P<0.0001). CONCLUSIONS: In the largest series of individuals with DSPtv, we demonstrate that variant location is a novel risk factor for ventricular arrhythmia, can inform variant interpretation, and provide critical insights to allow for precision-based clinical management.
Assuntos
Displasia Arritmogênica Ventricular Direita , Cardiomiopatias , Desmoplaquinas , Feminino , Humanos , Masculino , Arritmias Cardíacas/genética , Displasia Arritmogênica Ventricular Direita/diagnóstico , Cardiomiopatias/genética , Desmoplaquinas/genética , Fatores de RiscoRESUMO
Genomics is rapidly being integrated into the routine care of children and families living with renal disease, principally as a diagnostic tool but also to direct therapy, identify at-risk relatives, and facilitate family planning. However, despite significant progress in understanding the genetic heterogeneity of inherited renal disease, the impact of genetic testing on parents and families of affected children is not well understood. This study aimed to investigate the experiences of families undergoing genetic testing, the psychosocial impact of receiving a genetic test result, and parent information and support needs. In-depth semistructured interviews were conducted with 26 parents of pediatric patients (<18 years of age) who had undergone genomic investigation for a suspected genetic renal disease at two tertiary pediatric nephrology services. Interviews were transcribed verbatim, coded, using NVivo software, and thematic analysis was undertaken. Key themes included emotional adjustment to a genetic diagnosis, the importance of parent-provider relationships, empowerment through social connection, and the value of family-centered care. Results highlighted the wide-ranging psychosocial impact of genetic testing on parents, as well as the importance of patient-support networks in enabling parents/families to cope and adapt. Targeted approaches to enhance communication of genetic information and the development of tailored resources to address parents' genetics and health service needs may lead to more satisfactory experiences of genetic testing.
RESUMO
The choices of participants in nephrology research genomics studies about receiving additional findings (AFs) are unclear as are participant factors that might influence those choices. Methods: Participant choices and factors potentially impacting decisions about AFs were examined in an Australian study applying research genomic testing following uninformative diagnostic genetic testing for suspected monogenic kidney disease. Results: 93% of participants (195/210) chose to receive potential AFs. There were no statistically significant differences between those consenting to receive AFs or not in terms of gender (p = 0.97), median age (p = 0.56), being personally affected by the inherited kidney disease of interest (p = 0.38), or by the inheritance pattern (p = 0.12-0.19). Participants were more likely to choose not to receive AFs if the family proband presented in adulthood (p = 0.01), if there was family history of another genetic disorder (p = 0.01), and where the consent process was undertaken by an adult nephrologist (p = 0.01). Conclusion: The majority of participants in this nephrology research genomics study chose to receive potential AFs. Younger age of the family proband, family history of an alternate genetic disorder, and consenting by some multidisciplinary team members might impact upon participant choices.