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BACKGROUND: Overuse of sedation and anesthesia causes delays in gastrojejunostomy tube (GJ) exchanges, increased risk of complications, unnecessary use of resources, preventable hospital admissions, and an adverse impact on patient and family experience. Our hospital was over-utilizing sedation and anesthesia, and we aimed to decrease this use from 78% to 20% within two years. METHODS: An interdisciplinary quality improvement team comprehensively evaluated current processes for GJ tube exchanges through a retrospective chart review for baseline data with prospective time series analysis after improvement implementation. The primary outcome measure was the percentage of pediatric patients that utilized sedation or anesthesia for routine GJ tube exchanges. RESULTS: A statistical process control p-chart was used to calculate and show changes over time for patients (n = 45 patients average). The median percent of pediatric GJ tube exchanges performed with sedation or anesthesia decreased from 77.8% to 11.3%. Most patients (76%) were covered by Medicaid programs; with low reimbursement rates, decreased anesthesiologist billing revenue does not have a negative financial impact. CONCLUSIONS: An interprofessional improvement initiative that engaged patients and families, incorporated pediatric-specific staff services, and developed systematic weaning was associated with a significant decrease in the overuse of sedation and anesthesia for GJ tube exchanges. IMPACT: We believe that this work is highly relevant and impactful for medical centers caring for children who require gastrojejunostomy tubes, an increasingly common approach to management of children with feeding issues. There is very little literature available on the use of sedation or anesthesia for changing these tubes. While large children's medical centers in the USA usually do not utilize sedation or anesthesia, there are likely many serious outliers, especially when children receive care outside of a pediatric specific institution. This paper brings awareness to this serious issue and provides information about how we changed care to achieve higher patient safety and lower medical costs.
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The COVID-19 pandemic will leave an indelible mark on the careers of current medical trainees. Given the disruptions to medical education, economic impact on institutions, and the uncertainties around future job prospects, trainees are facing unprecedented challenges. This situation is especially concerning for futures of pediatric physician-scientist trainees, where concerns regarding maintaining the pipeline were well documented prior to the emergence of COVID-19. In this Perspectives article, we leverage the unique expertise of our workgroup to address concerns of physician-scientist trainees and to provide suggestions on how to navigate career trajectories in the post-COVID-19 era. We identified and addressed four major areas of concern: lack of in-person conferences and the associated decrease access to mentors and networking activities, decreased academic productivity, diminished job prospects, and mental health challenges. We also suggest actions for trainees, mentors and educational leaders, and institutions to help support trainees during the pandemic, with a goal of maintaining the pediatric physician-scientist pipeline.
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Pesquisa Biomédica/educação , COVID-19 , Educação de Pós-Graduação em Medicina , Mentores , Pediatras/educação , Pediatria/educação , Mobilidade Ocupacional , Eficiência , Humanos , Relações Interpessoais , Saúde Mental , Pediatras/psicologia , Sociedades MédicasRESUMO
Background: Coinfection with influenza virus and methicillin-resistant Staphylococcus aureus (MRSA) causes life-threatening necrotizing pneumonia in children. Sporadic incidence precludes evaluation of antimicrobial efficacy. We assessed the clinical characteristics and outcomes of critically ill children with influenza-MRSA pneumonia and evaluated antibiotic use. Methods: We enrolled children (<18 years) with influenza infection and respiratory failure across 34 pediatric intensive care units 11/2008-5/2016. We compared baseline characteristics, clinical courses, and therapies in children with MRSA coinfection, non-MRSA bacterial coinfection, and no bacterial coinfection. Results: We enrolled 170 children (127 influenza A, 43 influenza B). Children with influenza-MRSA pneumonia (N = 30, 87% previously healthy) were older than those with non-MRSA (N = 61) or no (N = 79) bacterial coinfections. Influenza-MRSA was associated with increased leukopenia, acute lung injury, vasopressor use, extracorporeal life support, and mortality than either group (P ≤ .0001). Influenza-related mortality was 40% with MRSA compared to 4.3% without (relative risk [RR], 9.3; 95% confidence interval [CI], 3.8-22.9). Of 29/30 children with MRSA who received vancomycin within the first 24 hours of hospitalization, mortality was 12.5% (N = 2/16) if treatment also included a second anti-MRSA antibiotic compared to 69.2% (N = 9/13) with vancomycin monotherapy (RR, 5.5; 95% CI, 1.4, 21.3; P = .003). Vancomycin dosing did not influence initial trough levels; 78% were <10 µg/mL. Conclusions: Influenza-MRSA coinfection is associated with high fatality in critically ill children. These data support early addition of a second anti-MRSA antibiotic to vancomycin in suspected severe cases.
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Antibacterianos/uso terapêutico , Coinfecção/tratamento farmacológico , Estado Terminal , Influenza Humana/complicações , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Pneumonia Estafilocócica/tratamento farmacológico , Vancomicina/uso terapêutico , Adolescente , Criança , Pré-Escolar , Coinfecção/microbiologia , Coinfecção/mortalidade , Coinfecção/patologia , Feminino , Humanos , Lactente , Recém-Nascido , Influenza Humana/mortalidade , Influenza Humana/patologia , Masculino , Pneumonia Estafilocócica/microbiologia , Pneumonia Estafilocócica/mortalidade , Pneumonia Estafilocócica/patologia , Estudos Prospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
The cell cycle must be tightly coordinated for proper control of embryonic development and for the long-term maintenance of organs such as the lung. There is emerging evidence that Kinesin family member 7 (Kif7) promotes Hedgehog (Hh) signaling during embryonic development, and its misregulation contributes to diseases such as ciliopathies and cancer. Kif7 encodes a microtubule interacting protein that controls Hh signaling through regulation of microtubule dynamics within the primary cilium. However, whether Kif7 has a function in nonciliated cells remains largely unknown. The role Kif7 plays in basic cell biological processes like cell proliferation or cell cycle progression also remains to be elucidated. Here, we show that Kif7 is required for coordination of the cell cycle, and inactivation of this gene leads to increased cell proliferation in vivo and in vitro. Immunostaining and transmission electron microscopy experiments show that Kif7dda/dda mutant lungs are hyperproliferative and exhibit reduced alveolar epithelial cell differentiation. KIF7 depleted C3H10T1/2 fibroblasts and Kif7dda/dda mutant mouse embryonic fibroblasts have increased growth rates at high cellular densities, suggesting that Kif7 may function as a general regulator of cellular proliferation. We ascertained that in G1, Kif7 and microtubule dynamics regulate the expression and activity of several components of the cell cycle machinery known to control entry into S phase. Our data suggest that Kif7 may function to regulate the maintenance of the respiratory airway architecture by controlling cellular density, cell proliferation, and cycle exit through its role as a microtubule associated protein.
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Proliferação de Células/genética , Desenvolvimento Embrionário/genética , Cinesinas/genética , Pulmão/crescimento & desenvolvimento , Animais , Cílios/genética , Cílios/fisiologia , Embrião de Mamíferos , Fibroblastos/metabolismo , Proteínas Hedgehog/genética , Cinesinas/metabolismo , Pulmão/metabolismo , Camundongos , Microtúbulos/genética , Microtúbulos/metabolismo , Ventilação Pulmonar , Transdução de Sinais/genéticaRESUMO
Congenital diaphragmatic hernia (CDH) is a common and severe birth defect. Despite its clinical significance, the genetic and developmental pathways underlying this disorder are incompletely understood. In this study, we report a catalog of variants detected by a whole exome sequencing study on 275 individuals with CDH. Predicted pathogenic variants in genes previously identified in either humans or mice with diaphragm defects are enriched in our CDH cohort compared with 120 size-matched random gene sets. This enrichment was absent in control populations. Variants in these critical genes can be found in up to 30.9% of individuals with CDH. In addition, we filtered variants by using genes derived from regions of recurrent copy number variations in CDH, expression profiles of the developing diaphragm, protein interaction networks expanded from the known CDH-causing genes, and prioritized genes with ultrarare and highly disruptive variants, in 11.3% of CDH patients. These strategies have identified several high priority genes and developmental pathways that likely contribute to the CDH phenotype. These data are valuable for comparison of candidate genes generated from whole exome sequencing of other CDH cohorts or multiplex kindreds and provide ideal candidates for further functional studies. Furthermore, we propose that these genes and pathways will enhance our understanding of the heterogeneous molecular etiology of CDH.
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Hérnias Diafragmáticas Congênitas/etiologia , Hérnias Diafragmáticas Congênitas/genética , Animais , Estudos de Coortes , Biologia Computacional , Variações do Número de Cópias de DNA , Diafragma/embriologia , Exoma , Variação Genética , Hérnias Diafragmáticas Congênitas/embriologia , Humanos , Camundongos , Mapas de Interação de ProteínasRESUMO
BACKGROUND: Development of methicillin-resistant Staphylococcus aureus (MRSA) pneumonia after a respiratory viral infection is frequently fatal in children. In mice, S. aureus α-toxin directly injures pneumocytes and increases mortality, whereas α-toxin blockade mitigates disease. The role of α-toxin in pediatric staphylococcal-viral coinfection is unclear. METHODS: We enrolled children across 34 North American pediatric intensive care units with acute respiratory failure and suspected influenza virus infection. Serial serum anti-α-toxin antibody titers and functional α-toxin neutralization capacity were compared across children coinfected with MRSA or methicillin-susceptible S. aureus (MSSA) and control children infected with influenza virus only. MRSA isolates were tested for α-toxin production and lethality in a murine pneumonia model. RESULTS: Influenza virus was identified in 22 of 25 children with MRSA coinfection (9 died) and 22 patients with MSSA coinfection (all survived). Initial α-toxin-specific antibody titers were similar, compared with those in the 13 controls. In patients with serial samples, only MRSA-coinfected patients showed time-dependent increases in anti-α-toxin titer and functional neutralization capacity. MRSA α-toxin production from patient isolates correlated with initial serologic titers and with mortality in murine pneumonia. CONCLUSIONS: These data implicate α-toxin as a relevant antigen in severe pediatric MRSA pneumonia associated with respiratory viral infection, supporting a potential role for toxin-neutralizing therapy.
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Anticorpos Antibacterianos/sangue , Toxinas Bacterianas/imunologia , Toxinas Bacterianas/toxicidade , Coinfecção/patologia , Proteínas Hemolisinas/imunologia , Proteínas Hemolisinas/toxicidade , Influenza Humana/complicações , Insuficiência Respiratória/patologia , Infecções Estafilocócicas/patologia , Adolescente , Experimentação Animal , Animais , Criança , Pré-Escolar , Coinfecção/complicações , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Resistência a Meticilina , Camundongos , Testes de Neutralização , América do Norte , Infecções Estafilocócicas/complicações , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação , Análise de SobrevidaRESUMO
The developing diaphragm consists of various differentiating cell types, many of which are not well characterized during organogenesis. One important but incompletely understood tissue, the diaphragmatic mesothelium, is distinctively present from early stages of development. Congenital Diaphragmatic Hernia (CDH) occurs in humans when diaphragm tissue is lost during development, resulting in high morbidity and mortality postnatally. We utilized a Wilms Tumor 1 (Wt1) mutant mouse model to investigate the involvement of the mesothelium in normal diaphragm signaling and development. Additionally, we developed and characterized a Wt1(CreERT2)-driven ß-catenin loss-of-function model of CDH after finding that canonical Wnt signaling and ß-catenin are reduced in Wt1 mutant mesothelium. Mice with ß-catenin loss or constitutive activation induced in the Wt1 lineage are only affected when tamoxifen injection occurs between E10.5 and E11.5, revealing a critical time-frame for Wt1/ ß-catenin activity. Conditional ß-catenin loss phenocopies the Wt1 mutant diaphragm defect, while constitutive activation of ß-catenin on the Wt1 mutant background is sufficient to close the diaphragm defect. Proliferation and apoptosis are affected, but primarily these genetic manipulations appear to lead to a change in normal diaphragm differentiation. Our data suggest a fundamental role for mesothelial signaling in proper formation of the diaphragm.
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Diafragma/embriologia , Proteínas Repressoras/fisiologia , Transdução de Sinais , beta Catenina/fisiologia , Animais , Apoptose , Diferenciação Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Hérnias Diafragmáticas Congênitas/etiologia , Humanos , Camundongos , Especificidade de Órgãos , Proteínas WT1RESUMO
Congenital diaphragmatic hernia (CDH) is a common birth defect that results in a high degree of neonatal morbidity and mortality, but its pathological mechanisms are largely unknown. Therefore, we performed a forward genetic screen in mice to identify unique genes, models, and mechanisms of abnormal diaphragm development. We identified a mutant allele of kinesin family member 7 (Kif7), the disorganized diaphragm (dd). Embryos homozygous for the dd allele possess communicating diaphragmatic hernias, central tendon patterning defects, and increased cell proliferation with diaphragmatic tissue hyperplasia. Because the patterning of the central tendon is undescribed, we analyzed the expression of genes regulating tendonogenesis in dd/dd mutant embryos, and we determined that retinoic acid (RA) signaling was misregulautted. To further investigate the role of Kif7 and RA signaling in the development of the embryonic diaphragm, we established primary mesenchymal cultures of WT embryonic day 13.5 diaphragmatic cells. We determined that RA signaling is necessary for the expression of tendon markers as well as the expression of other CDH-associated genes. Knockdown of Kif7, and retinoic acid receptors alpha (Rara), beta (Rarb), and gamma (Rarg) indicated that RA signaling is dependent on these genes to promote tendonogenesis within the embryonic diaphragm. Taken together, our results provide evidence for a model in which inhibition of RA receptor signaling promotes CDH pathogenesis through a complex gene network.
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Padronização Corporal , Diferenciação Celular , Diafragma/embriologia , Hérnias Diafragmáticas Congênitas , Cinesinas/metabolismo , Proteínas Musculares/metabolismo , Transdução de Sinais , Alelos , Animais , Linhagem Celular , Diafragma/patologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Hérnia Diafragmática/embriologia , Hérnia Diafragmática/genética , Hérnia Diafragmática/patologia , Cinesinas/genética , Camundongos , Camundongos Mutantes , Proteínas Musculares/genética , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico , Tendões/embriologia , Tendões/patologia , Tretinoína/metabolismo , Receptor gama de Ácido RetinoicoAssuntos
Hospitais Pediátricos/organização & administração , Internato e Residência , Pediatria/educação , Escolha da Profissão , Criança , Financiamento Governamental , Humanos , Mentores , National Institutes of Health (U.S.) , Pediatras , Pediatria/organização & administração , Apoio à Pesquisa como Assunto , Apoio ao Desenvolvimento de Recursos Humanos/organização & administração , Pesquisa Translacional Biomédica/educação , Estados UnidosRESUMO
Congenital diaphragmatic hernia (CDH) is a common (1 in 3,000 live births) major congenital malformation that results in significant morbidity and mortality. The discovery of CDH loci using standard genetic approaches has been hindered by its genetic heterogeneity. We hypothesized that gene expression profiling of developing embryonic diaphragms would help identify genes likely to be associated with diaphragm defects. We generated a time series of whole-transcriptome expression profiles from laser captured embryonic mouse diaphragms at embryonic day (E)11.5 and E12.5 when experimental perturbations lead to CDH phenotypes, and E16.5 when the diaphragm is fully formed. Gene sets defining biologically relevant pathways and temporal expression trends were identified by using a series of bioinformatic algorithms. These developmental sets were then compared with a manually curated list of genes previously shown to cause diaphragm defects in humans and in mouse models. Our integrative filtering strategy identified 27 candidates for CDH. We examined the diaphragms of knockout mice for one of the candidate genes, pre-B-cell leukemia transcription factor 1 (Pbx1), and identified a range of previously undetected diaphragmatic defects. Our study demonstrates the utility of genetic characterization of normal development as an integral part of a disease gene identification and prioritization strategy for CDH, an approach that can be extended to other diseases and developmental anomalies.
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Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/patologia , Estudos de Associação Genética , Hérnias Diafragmáticas Congênitas , Transcriptoma/genética , Animais , Diafragma/embriologia , Diafragma/metabolismo , Diafragma/patologia , Regulação da Expressão Gênica no Desenvolvimento , Hérnia Diafragmática/genética , Hérnia Diafragmática/patologia , Proteínas de Homeodomínio/metabolismo , Lasers , Mesoderma/embriologia , Mesoderma/metabolismo , Mesoderma/patologia , Camundongos , Camundongos Knockout , Modelos Biológicos , Fator de Transcrição 1 de Leucemia de Células Pré-B , Transdução de Sinais/genética , Fatores de Tempo , Fatores de Transcrição/deficiência , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
There is a wide variation among humans and mice in airway hyperresponsiveness (AHR) in the absence of allergen sensitization, i.e., naïve AHR. Because mast cell (MC) activation is thought to mediate AHR in atopic asthmatic subjects, we asked whether MCs mediate naïve AHR in A/J mice. We generated an A/J congenic strain lacking c-Kit by introgression of the Wv mutation, which resulted in the elimination of MCs and the abrogation of naïve AHR. Imatinib, which disrupts Kit signaling, also abrogated AHR in A/J mice. Remarkably, introduction of the Vga9 Mitf mutation into the A/J background resulted in the ablation of MCs but did not ameliorate AHR. These results indicate that c-Kit is required for development of AHR in an MC-independent fashion.
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Hiper-Reatividade Brônquica/genética , Mastócitos/metabolismo , Proteínas Proto-Oncogênicas c-kit/genética , Transdução de Sinais/genética , Transferência Adotiva , Animais , Benzamidas , Hiper-Reatividade Brônquica/imunologia , Contagem de Células , Células Cultivadas , Feminino , Mesilato de Imatinib , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Mastócitos/patologia , Cloreto de Metacolina/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Linhagem , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Baço/efeitos dos fármacos , Baço/metabolismo , Baço/patologia , Traqueia/efeitos dos fármacos , Traqueia/metabolismo , Traqueia/patologiaRESUMO
BACKGROUND: Timely trial start-up is a key determinant of trial success; however, delays during start-up are common and costly. Moreover, data on start-up metrics in pediatric clinical trials are sparse. To expedite trial start-up, the Trial Innovation Network piloted three novel mechanisms in the trial titled Dexmedetomidine Opioid Sparing Effect in Mechanically Ventilated Children (DOSE), a multi-site, randomized, double-blind, placebo-controlled trial in the pediatric intensive care setting. METHODS: The three novel start-up mechanisms included: 1) competitive activation; 2) use of trial start-up experts, called site navigators; and 3) supplemental funds earned for achieving pre-determined milestones. After sites were activated, they received a web-based survey to report perceptions of the DOSE start-up process. In addition to perceptions, metrics analyzed included milestones met, time to start-up, and subsequent enrollment of subjects. RESULTS: Twenty sites were selected for participation, with 19 sites being fully activated. Across activated sites, the median (quartile 1, quartile 3) time from receipt of regulatory documents to site activation was 82 days (68, 113). Sites reported that of the three novel mechanisms, the most motivating factor for expeditious activation was additional funding available for achieving start-up milestones, followed by site navigator assistance and then competitive site activation. CONCLUSION: Study start-up is a critical time for the success of clinical trials, and innovative methods to minimize delays during start-up are needed. Milestone-based funds and site navigators were preferred mechanisms by sites participating in the DOSE study and may have contributed to the expeditious start-up timeline achieved. CLINICALTRIALS: gov #: NCT03938857.
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Analgésicos Opioides , Humanos , Criança , Método Duplo-Cego , Fatores de TempoRESUMO
Background: Influenza virus is responsible for a large global burden of disease, especially in children. Multiple Organ Dysfunction Syndrome (MODS) is a life-threatening and fatal complication of severe influenza infection. Methods: We measured RNA expression of 469 biologically plausible candidate genes in children admitted to North American pediatric intensive care units with severe influenza virus infection with and without MODS. Whole blood samples from 191 influenza-infected children (median age 6.4 years, IQR: 2.2, 11) were collected a median of 27 hours following admission; for 45 children a second blood sample was collected approximately seven days later. Extracted RNA was hybridized to NanoString mRNA probes, counts normalized, and analyzed using linear models controlling for age and bacterial co-infections (FDR q<0.05). Results: Comparing pediatric samples collected near admission, children with Prolonged MODS for ≥7 days (n=38; 9 deaths) had significant upregulation of nine mRNA transcripts associated with neutrophil degranulation (RETN, TCN1, OLFM4, MMP8, LCN2, BPI, LTF, S100A12, GUSB) compared to those who recovered more rapidly from MODS (n=27). These neutrophil transcripts present in early samples predicted Prolonged MODS or death when compared to patients who recovered, however in paired longitudinal samples, they were not differentially expressed over time. Instead, five genes involved in protein metabolism and/or adaptive immunity signaling pathways (RPL3, MRPL3, HLA-DMB, EEF1G, CD8A) were associated with MODS recovery within a week. Conclusion: Thus, early increased expression of neutrophil degranulation genes indicated worse clinical outcomes in children with influenza infection, consistent with reports in adult cohorts with influenza, sepsis, and acute respiratory distress syndrome.
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Infecções Bacterianas , Influenza Humana , Humanos , Insuficiência de Múltiplos Órgãos/genética , Influenza Humana/genética , Influenza Humana/complicações , Transcriptoma , Fenótipo , Hospitalização , Infecções Bacterianas/complicaçõesAssuntos
Atitude do Pessoal de Saúde , Certificação/normas , Competência Clínica/normas , Conhecimentos, Atitudes e Prática em Saúde , Satisfação no Emprego , Pediatras/normas , Pediatria/normas , Certificação/economia , Competência Clínica/economia , Análise Custo-Benefício , Humanos , Pediatras/economia , Pediatras/psicologia , Pediatria/economia , PercepçãoRESUMO
BACKGROUND: The striated preferentially expressed gene (Speg) generates 4 different isoforms through alternative promoter use and tissue-specific splicing. Depending on the cell type, Speg isoforms may serve as markers of striated or smooth muscle differentiation. METHODS AND RESULTS: To elucidate function of Speg gene isoforms, we disrupted the Speg gene locus in mice by replacing common exons 8, 9, and 10 with a lacZ gene. beta-Galactosidase activity was detected in cardiomyocytes of the developing heart starting at day 11.5 days post coitum (dpc). beta-Galactosidase activity in other cell types, including vascular smooth muscle cells, did not begin until 18.5 dpc. In the developing heart, protein expression of only Spegalpha and Spegbeta isoforms was present in cardiomyocytes. Homozygous Speg mutant hearts began to enlarge by 16.5 dpc, and by 18.5 dpc, they demonstrated dilation of right and left atria and ventricles. These cardiac abnormalities in the absence of Speg were associated with a cellular hypertrophic response, myofibril degeneration, and a marked decrease in cardiac function. Moreover, Speg mutant mice exhibited significant neonatal mortality, with increased death occurring by 2 days after birth. CONCLUSIONS: These findings demonstrate that mutation of the Speg locus leads to cardiac dysfunction and a phenotype consistent with a dilated cardiomyopathy.
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Cardiomiopatia Dilatada/enzimologia , Cardiomiopatia Dilatada/genética , Proteínas Musculares/biossíntese , Proteínas Musculares/genética , Quinase de Cadeia Leve de Miosina/biossíntese , Quinase de Cadeia Leve de Miosina/genética , Animais , Animais Recém-Nascidos , Cardiomiopatia Dilatada/etiologia , Marcação de Genes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Proteínas Musculares/deficiência , Mutagênese Sítio-Dirigida , Quinase de Cadeia Leve de Miosina/deficiênciaRESUMO
Cytogenetic and molecular cytogenetic studies demonstrate association between congenital diaphragmatic hernia (CDH) and chromosome 1q41q42 deletions. In this study, we screened a large CDH cohort (N=179) for microdeletions in this interval by the multiplex ligation-dependent probe amplification (MLPA) technique, and also sequenced two candidate genes located therein, dispatched 1 (DISP1) and homo sapiens H2.0-like homeobox (HLX). MLPA analysis verified deletions of this region in two cases, an unreported patient with a 46,XY,del(1)(q41q42.13) karyotype and a previously reported patient with a Fryns syndrome phenotype [Kantarci et al., 2006]. HLX sequencing showed a novel but maternally inherited single nucleotide variant (c.27C>G) in a patient with isolated CDH, while DISP1 sequencing revealed a mosaic de novo heterozygous substitution (c.4412C>G; p.Ala1471Gly) in a male with a left-sided Bochdalek hernia plus multiple other anomalies. Pyrosequencing demonstrated the mutant allele was present in 43%, 12%, and 4.5% of the patient's lymphoblastoid, peripheral blood lymphocytes, and saliva cells, respectively. We examined Disp1 expression at day E11.5 of mouse diaphragm formation and confirmed its presence in the pleuroperitoneal fold, as well as the nearby lung which also expresses Sonic hedgehog (Shh). Our report describes the first de novo DISP1 point mutation in a patient with complex CDH. Combining this finding with Disp1 embryonic mouse diaphragm and lung tissue expression, as well as previously reported human chromosome 1q41q42 aberrations in patients with CDH, suggests that DISP1 may warrant further consideration as a CDH candidate gene.
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Cromossomos Humanos Par 1 , Anormalidades Congênitas/genética , Hérnia Diafragmática/genética , Criança , Mapeamento Cromossômico , DNA/sangue , DNA/genética , DNA/isolamento & purificação , Primers do DNA , Feminino , Proteínas Hedgehog/genética , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Consentimento Livre e Esclarecido , Pulmão/fisiologia , Masculino , Mosaicismo , Deleção de SequênciaRESUMO
Variants in the mitochondrial alanyl-tRNA synthetase 2 gene AARS2 (OMIM 612035) are associated with infantile mitochondrial cardiomyopathy or later-onset leukoencephalopathy with premature ovarian insufficiency. Here, we report two newborn siblings who died soon after birth with primary pulmonary hypoplasia without evidence of cardiomyopathy. Whole-exome sequencing detected the same compound heterozygous AARS2 variants in both siblings (c.1774C>T, p.Arg592Trp and c.647dup, p.Cys218Leufs*6) that have previously been associated with infantile mitochondrial cardiomyopathy. Segregation analysis in the family confirmed carrier status of the parents and an unaffected sibling. To our knowledge, this is the first report of primary pulmonary hypoplasia in the absence of cardiomyopathy associated with recessive AARS2 variants and further defines the phenotypic spectrum associated with this gene.
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Anormalidades Múltiplas/genética , Alanina-tRNA Ligase/genética , Leucoencefalopatias/genética , Pneumopatias/genética , Pulmão/anormalidades , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/patologia , Substituição de Aminoácidos , Evolução Fatal , Mutação da Fase de Leitura , Genes Recessivos , Heterozigoto , Humanos , Recém-Nascido , Leucoencefalopatias/diagnóstico , Leucoencefalopatias/patologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pneumopatias/diagnóstico por imagem , Pneumopatias/patologia , Mitocôndrias/genética , Mitocôndrias/patologia , Linhagem , Fenótipo , Irmãos , Sequenciamento do ExomaRESUMO
Anterior diaphragmatic defects with pericardial involvement are extremely rare and diagnostically challenging entities encountered perinatally. While a majority of diaphragmatic defects occur in isolation, others are associated with multiple defects forming a complex of syndromes such as Pentalogy of Cantrell. Liver herniation into the pericardial sac poses a particular challenge and can mimic a pericardial tumor on prenatal ultrasound, yielding a different management course. The following case is an unusual presentation of a 30-week gestation female with an anterior midline diaphragmatic defect with liver herniation mimicking as a pericardial tumor, diagnosed at time of autopsy. Postmortem studies also found multiple congenital anomalies including an atrioventricular septal defect and midline gumline defect suggesting at least a partial Pentalogy of Cantrell or variant. Early recognition and screening for associated anomalies are essential for management in this subset of patients.
Assuntos
Anormalidades Múltiplas/diagnóstico , Cardiopatias/diagnóstico , Hérnias Diafragmáticas Congênitas/diagnóstico , Doenças do Prematuro/diagnóstico , Hepatopatias/diagnóstico , Pericárdio , Anormalidades Múltiplas/patologia , Evolução Fatal , Feminino , Cardiopatias/congênito , Cardiopatias/patologia , Hérnia/congênito , Hérnia/diagnóstico , Hérnia/patologia , Hérnias Diafragmáticas Congênitas/patologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/patologia , Hepatopatias/congênito , Hepatopatias/patologia , Pericárdio/diagnóstico por imagem , Pericárdio/patologia , Diagnóstico Pré-NatalRESUMO
Congenital diaphragmatic hernias (CDHs) and structural anomalies of the diaphragm are a common class of congenital birth defects that are associated with significant morbidity and mortality due to associated pulmonary hypoplasia, pulmonary hypertension and heart failure. In â¼30% of CDH patients, genomic analyses have identified a range of genetic defects, including chromosomal anomalies, copy number variants and sequence variants. The affected genes identified in CDH patients include transcription factors, such as GATA4, ZFPM2, NR2F2 and WT1, and signaling pathway components, including members of the retinoic acid pathway. Mutations in these genes affect diaphragm development and can have pleiotropic effects on pulmonary and cardiac development. New therapies, including fetal endoscopic tracheal occlusion and prenatal transplacental fetal treatments, aim to normalize lung development and pulmonary vascular tone to prevent and treat lung hypoplasia and pulmonary hypertension, respectively. Studies of the association between particular genetic mutations and clinical outcomes should allow us to better understand the origin of this birth defect and to improve our ability to predict and identify patients most likely to benefit from specialized treatment strategies.