RESUMO
BACKGROUND: Hematopoietic cell transplantation (HCT) is an established curative therapy for transfusion-dependent thalassemia (TDT) and sickle cell disease (SCD). The latest American Society of Hematology guidelines recommend myeloablative preparative regimen in patients under 18 years of age. PROCEDURE: The objective was to demonstrate safety and efficacy of a reduced intensity conditioning (RIC) regimen including high-dose fludarabine, anti-thymocyte globulin, and targeted busulfan as a single alkylator to sub-myeloablative exposures. RESULTS: Between 2012 and 2021, 11 patients with SCD and five patients with TDT and matched related donor (MRD) HCT were included. The median age at transplantation was 8.3 years (range: 3.7-18.8 years). The median administered busulfan AUC was 67.4 mg/L×h (range: 60.7-80 mg/L×h). Overall survival was 93.8% and event-free survival 87.5% with one engrafted SCD patient with pre-existing moyamoya disease succumbing after drainage of a subdural hematoma. One SCD patient developed a secondary graft failure and was treated with a second HCT. Myeloid chimerism was full in all other patients with a median follow-up time of 4.1 years (range: 2.0-11.1 years), whereas T-cell donor chimerism was frequently mixed. CONCLUSION: This RIC conditioning followed by MRD HCT is sufficiently myeloablative to cure pediatric patients with hemoglobinopathies without the need for additional total body irradiation or thiotepa.
Assuntos
Bussulfano , Transplante de Células-Tronco Hematopoéticas , Hemoglobinopatias , Condicionamento Pré-Transplante , Humanos , Bussulfano/administração & dosagem , Bussulfano/uso terapêutico , Condicionamento Pré-Transplante/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Pré-Escolar , Criança , Masculino , Feminino , Adolescente , Hemoglobinopatias/terapia , Seguimentos , Taxa de Sobrevida , Doença Enxerto-Hospedeiro/etiologia , Sobrevivência de Enxerto , Vidarabina/análogos & derivados , Vidarabina/administração & dosagem , Vidarabina/uso terapêutico , Anemia Falciforme/terapia , Doadores de Tecidos , Prognóstico , Talassemia/terapiaRESUMO
Germline SAMD9 and SAMD9L mutations (SAMD9/9Lmut) predispose to myelodysplastic syndromes (MDS) with propensity for somatic rescue. In this study, we investigated a clinically annotated pediatric MDS cohort (n = 669) to define the prevalence, genetic landscape, phenotype, therapy outcome and clonal architecture of SAMD9/9L syndromes. In consecutively diagnosed MDS, germline SAMD9/9Lmut accounted for 8% and were mutually exclusive with GATA2 mutations present in 7% of the cohort. Among SAMD9/9Lmut cases, refractory cytopenia was the most prevalent MDS subtype (90%); acquired monosomy 7 was present in 38%; constitutional abnormalities were noted in 57%; and immune dysfunction was present in 28%. The clinical outcome was independent of germline mutations. In total, 67 patients had 58 distinct germline SAMD9/9Lmut clustering to protein middle regions. Despite inconclusive in silico prediction, 94% of SAMD9/9Lmut suppressed HEK293 cell growth, and mutations expressed in CD34+ cells induced overt cell death. Furthermore, we found that 61% of SAMD9/9Lmut patients underwent somatic genetic rescue (SGR) resulting in clonal hematopoiesis, of which 95% was maladaptive (monosomy 7 ± cancer mutations), and 51% had adaptive nature (revertant UPD7q, somatic SAMD9/9Lmut). Finally, bone marrow single-cell DNA sequencing revealed multiple competing SGR events in individual patients. Our findings demonstrate that SGR is common in SAMD9/9Lmut MDS and exemplify the exceptional plasticity of hematopoiesis in children.
Assuntos
Evolução Clonal/genética , Hematopoiese Clonal/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Síndromes Mielodisplásicas/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Células da Medula Óssea/metabolismo , Criança , Pré-Escolar , Feminino , Fator de Transcrição GATA2/genética , Mutação em Linhagem Germinativa/genética , Células HEK293 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Síndromes Mielodisplásicas/patologia , Análise de Célula ÚnicaAssuntos
Anemia Refratária/patologia , Hemoglobinúria Paroxística/patologia , Síndromes Mielodisplásicas/complicações , Pancitopenia/patologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Adolescente , Anemia Refratária/etiologia , Criança , Pré-Escolar , Feminino , Seguimentos , Hemoglobinúria Paroxística/etiologia , Humanos , Lactente , Masculino , Pancitopenia/etiologia , Prognóstico , Estudos RetrospectivosRESUMO
PURPOSE: Intraoperative bleeding should be regularly assessed visually to guide coagulation management. Whereas viscoelastic testing with ROTEM® measurement has been proven to be useful in detecting coagulopathies, the visual assessment is not standardized. This study therefore aims to compare a standardized visual assessment with ROTEM® results. METHODS: A 5-point bleeding score was created and applied in a recently published randomized controlled trial in major pediatric non-cardiac surgery. This score assesses overall bleeding tendency and the occurrence of diffuse bleeding, aqueous bleeding, bleeding outside the operative field, and the ability to control bleeding. Validity of this score was tested by post hoc comparison to the results of simultaneously performed ROTEM® measurements. RESULTS: Signs of coagulopathic bleeding were assessed at 183 time points. Mild to moderate bleeding intensity was judged at 103 time points, in 42 % abnormal ROTEM® traces were obtained simultaneously. When severe bleeding was scored, abnormal ROTEM values occurred in 58 %, and FIBTEM-values were significantly lower than in the "no bleeding group". Altogether, the correlation between bleeding score and ROTEM® measurements was not significant. CONCLUSIONS: The standardized visual assessment did not correlate well with ROTEM® measurements, suggesting that it is not useful to detect coagulopathy. Trial registry number: ClinicalTrials.gov identifier No. NCT01487837.
Assuntos
Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/terapia , Testes de Coagulação Sanguínea/instrumentação , Testes de Coagulação Sanguínea/métodos , Coagulação Sanguínea , Pediatria/métodos , Tromboelastografia/métodos , Adolescente , Transfusão de Sangue , Criança , Pré-Escolar , Craniossinostoses/complicações , Craniossinostoses/cirurgia , Feminino , Hemorragia , Humanos , Lactente , Masculino , Estudos Prospectivos , Padrões de Referência , Escoliose/complicações , Escoliose/cirurgiaRESUMO
Diamond-Blackfan anemia (DBA) is caused mainly by genetic mutations in large (RPL) or small ribosomal subunit genes (RPS) and presents with macrocytic anemia and congenital malformations. Clinical differences between genotypes are insufficiently understood. The aim of this study was to assess clinical features, treatment strategies, and genotypes in the Swiss pediatric DBA population. We retrospectively reviewed medical charts of pediatric patients with DBA in Switzerland and stratified patients by RPL versus RPS mutations. We report 17 DBA patients in Switzerland who were all genetically investigated. In our cohort, patients showed a wide spectrum of clinical presentations and treatment needs. We found a high proportion of physical malformations (77%) including lower limb (17%) and anorectal (12%) malformations. The two patients with anorectal malformations presented both with antepositioning of the anus needing surgery within the first 15 months of life. One of these patients had sphincteric dysfunction, the other coccygeal agenesis. We found that included patients with an RPL mutation more frequently tended to have physical malformations and a milder anemia compared to patients with an RPS mutation (median hemoglobin at diagnosis 76 g/l versus 22 g/l).Conclusion: We illustrate the wide clinical and genetic spectrum of DBA in Switzerland. Our findings highlight the need to take this diagnosis into consideration in patients with severe anemia but also in patients with mild anemia where malformations are present. Lower limb and anorectal malformation extend the spectrum of DBA-associated malformations. What is Known? ⢠There is a large variation in the phenotype of Diamond-Blackfan Anemia (DBA) and diversity of genetic mutations. ⢠Malformation of the upper limbs, head and face, heart, and genitourinary system is frequently identified. What is New? ⢠Patients with lower limb and anorectal malformations were repetitively found in our cohort enlarging the clinical spectrum of malformations. ⢠We show two patients of the same family with a DBA-like condition where the same RPL17 variant was identified.
Assuntos
Anemia de Diamond-Blackfan , Anemia de Diamond-Blackfan/diagnóstico , Anemia de Diamond-Blackfan/genética , Criança , Genótipo , Humanos , Mutação , Fenótipo , Estudos Retrospectivos , Proteínas Ribossômicas/genética , Suíça/epidemiologiaRESUMO
BACKGROUND: Apoptotic pathways in platelets are important for their survival and function. Platelet apoptosis may be involved in the pathogenesis of immune thrombocytopenia (ITP), an autoimmune-mediated disease. In contrast to the intrinsic apoptosis pathway, not much is known about the extrinsic pathway mechanisms in platelets. OBJECTIVES: To investigate the expression of proteins involved in the extrinsic apoptosis pathway, including the death receptors, adaptor and regulator proteins in human platelets. To determine a possible trigger of the extrinsic apoptosis pathway in platelets. METHODS: To investigate the expression of key markers of the extrinsic pathway we used targeted immunofluorescence and flow cytometry assays. To study their expression and interaction we performed Western blotting and co-immunoprecipitation. Treated platelets with different apoptosis triggers were subjected to flow cytometry. RESULTS: We could identify the protein expression of the pro-apoptotic proteins TRADD (Tumor Necrosis Factor Receptor type 1- Associated DEATH Domain protein), TRAF2/5, (TNF Associated Factor) and DEDAF (Death Effector Domain- Associated Factor), FADD (Fas-Associated protein with death domain) as well as the anti-apoptotic proteins DJ-1 (Deglycase 1) and c-FLIP in human platelets. ABT-737 treatment induced a disruption in the co-localization of DJ-1 with FADD. Platelets treated with ABT-737 showed an activation in caspase-3 and -8. The exposure to TNF (Tumor Necrosis Factor), FasL (Fas ligand), and TWEAK or to plasma derived from ITP patients, did not lead to changes in caspase-3 and -8 activation in platelets. CONCLUSIONS: Human platelets express some proteins of the extrinsic apoptosis pathway which can be modulated only by ABT-737 treatment. However so far, no other apoptosis trigger or interaction with an external receptor have been yet identified.
Assuntos
Apoptose , Plaquetas/citologia , Plaquetas/metabolismo , Caspase 8/metabolismo , Regulação da Expressão Gênica , Criança , Ativação Enzimática , Proteína de Domínio de Morte Associada a Fas/metabolismo , Feminino , Humanos , Masculino , Proteína Desglicase DJ-1/metabolismo , Transporte ProteicoRESUMO
Deficiency of the transcription factor GATA2 is a highly penetrant genetic disorder predisposing to myelodysplastic syndromes (MDS) and immunodeficiency. It has been recognized as the most common cause underlying primary MDS in children. Triggered by the discovery of a recurrent synonymous GATA2 variant, we systematically investigated 911 patients with phenotype of pediatric MDS or cellular deficiencies for the presence of synonymous alterations in GATA2. In total, we identified nine individuals with five heterozygous synonymous mutations: c.351C>G, p.T117T (N = 4); c.649C>T, p.L217L; c.981G>A, p.G327G; c.1023C>T, p.A341A; and c.1416G>A, p.P472P (N = 2). They accounted for 8.2% (9/110) of cases with GATA2 deficiency in our cohort and resulted in selective loss of mutant RNA. While for the hotspot mutation (c.351C>G) a splicing error leading to RNA and protein reduction was identified, severe, likely late stage RNA loss without splicing disruption was found for other mutations. Finally, the synonymous mutations did not alter protein function or stability. In summary, synonymous GATA2 substitutions are a new common cause of GATA2 deficiency. These findings have broad implications for genetic counseling and pathogenic variant discovery in Mendelian disorders.
Assuntos
Deficiência de GATA2/genética , Fator de Transcrição GATA2/deficiência , Fator de Transcrição GATA2/genética , RNA/genética , Mutação Silenciosa/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa/genética , Heterozigoto , Humanos , Síndromes de Imunodeficiência/genética , Masculino , Síndromes Mielodisplásicas/genética , Fenótipo , Adulto JovemRESUMO
Immune thrombocytopenia (ITP) is an autoimmune disease which leads to accelerated platelet clearance. We investigated the plasma cytokine, chemokine and growth factor signatures and their clinical significance in pediatric ITP patients during acute, chronic and follow-up stages as well as the effects of intravenous immunoglobulin (IVIg) treatment, by using the Multiplex technology. In acute ITP before and/or after IVIg treatment we found significantly increased plasma levels of the pro- (tumour necrosis factor-α (TNF-α), interleukin IL-15) and anti- (IL-1 receptor antagonist (Ra), IL-10 and the growth factor interferon γ-induced protein (IP-10)) inflammatory cytokines, compared to healthy controls. Except for IL1-Ra, these cytokines decreased to normal levels in chronic patients. In contrast, growth-regulated α protein (GRO) and soluble CD40 ligand (sCD40L), known as platelet-derived molecules, were found to be significantly decreased in acute and increased in chronic ITP patients compared to healthy controls. GRO levels positively correlated with the platelet counts in the follow-up and chronic cohort. Monocyte counts showed a significant positive correlation only with IP-10 levels in acute ITP after IVIg treatment and follow-up patients. Expression levels of mRNAs for macrophage inflammatory protein MIP1-ß, IL-1Ra and GRO determined in peripheral blood mononuclear cells (PBMCs) were significantly reduced in both acute and chronic ITP compared to controls. Our findings suggest that the different clinical presentation of acute and chronic pediatric ITP and to a lesser extent the IVIg treatment effects are characterized overall by a counterbalanced cytokine, chemokine and growth factor pattern response that might exert a pathogenic role in this disease.
RESUMO
Iron deficiency is the most prevalent nutritional deficiency affecting children and adolescents worldwide. A consistent body of epidemiological data demonstrates an increased incidence of iron deficiency at three timepoints: in the neonatal period, in preschool children, and in adolescents, where it particularly affects females.Conclusion: This narrative review focuses on the most suggestive symptoms of iron deficiency in childhood, describes the diagnostic procedures in situations with or without anemia, and provides Swiss expert-based management recommendations for the pediatric context.What is Known:⢠Iron deficiency (ID) is one of the most common challenges faced by pediatricians.⢠Significant progress in the diagnosis and therapy of ID has been made over the last decade.What is New:⢠Our expert panel provides ID management recommendations based on the best available evidence.⢠They include strategies for ID diagnosis and therapy, both oral and intravenous.
Assuntos
Anemia Ferropriva , Ferro , Administração Intravenosa/efeitos adversos , Administração Oral , Adolescente , Anemia Ferropriva/sangue , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/fisiopatologia , Anemia Ferropriva/terapia , Criança , Pré-Escolar , Consenso , Compostos Férricos/administração & dosagem , Compostos Férricos/efeitos adversos , Compostos Férricos/economia , Ferritinas/sangue , Humanos , Lactente , Recém-Nascido , Ferro/sangue , Deficiências de Ferro , Ferro da Dieta/normas , Pediatria/métodos , SuíçaAssuntos
Anemia/etiologia , Tumor Carcinoide/terapia , Catéteres/efeitos adversos , Quimioembolização Terapêutica/efeitos adversos , Hemoglobinas Anormais , Neoplasias Intestinais/terapia , Neoplasias Hepáticas/terapia , Idoso , Anemia/genética , Tumor Carcinoide/genética , Tumor Carcinoide/patologia , Humanos , Neoplasias Intestinais/genética , Neoplasias Intestinais/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Masculino , Metástase NeoplásicaRESUMO
Juvenile myelomonocytic leukemia (JMML) is an aggressive myeloproliferative disorder of early childhood characterized by mutations activating RAS signaling. Established clinical and genetic markers fail to fully recapitulate the clinical and biological heterogeneity of this disease. Here we report DNA methylome analysis and mutation profiling of 167 JMML samples. We identify three JMML subgroups with unique molecular and clinical characteristics. The high methylation group (HM) is characterized by somatic PTPN11 mutations and poor clinical outcome. The low methylation group is enriched for somatic NRAS and CBL mutations, as well as for Noonan patients, and has a good prognosis. The intermediate methylation group (IM) shows enrichment for monosomy 7 and somatic KRAS mutations. Hypermethylation is associated with repressed chromatin, genes regulated by RAS signaling, frequent co-occurrence of RAS pathway mutations and upregulation of DNMT1 and DNMT3B, suggesting a link between activation of the DNA methylation machinery and mutational patterns in JMML.
Assuntos
Metilação de DNA , Leucemia Mielomonocítica Juvenil/genética , Síndrome de Noonan/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/genética , Antineoplásicos/uso terapêutico , Biópsia , Criança , Pré-Escolar , Cromatina/genética , Cromatina/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Análise Mutacional de DNA , Epigenômica , Feminino , Regulação Leucêmica da Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Leucemia Mielomonocítica Juvenil/mortalidade , Leucemia Mielomonocítica Juvenil/patologia , Leucemia Mielomonocítica Juvenil/terapia , Masculino , Mutação , Síndrome de Noonan/patologia , Prognóstico , Estudos Prospectivos , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteínas Proto-Oncogênicas c-cbl , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Regulação para Cima , DNA Metiltransferase 3BRESUMO
Thrombocytopenia absent radii (TAR) syndrome is clearly defined by the combination of radial aplasia and reduced platelet counts. The genetics of TAR syndrome has recently been resolved and comprises a microdeletion on Chromosome 1 including the RBM8A gene and a single nucleotide polymorphism (SNP) either at the 5' untranslated region (5'UTR) or within the first intron of RBM8A. Although phenotypically readily diagnosed after birth, the genetic determination of particular SNPs in TAR syndrome harbours valuable information to evaluate disease severity and treatment decisions. Here, we present clinical data in a cohort of 38 patients and observed that platelet counts in individuals with 5'UTR SNP are significantly lower compared to patients bearing the SNP in intron 1. Moreover, elevated haemoglobin values could only be assessed in patients with 5'UTR SNP whereas white blood cell count is unaffected, indicating that frequently observed anaemia in TAR patients could also be SNP-dependent whereas leucocytosis does not correlate with genetic background. However, this report on a large cohort provides an overview of important haematological characteristics in TAR patients, facilitating evaluation of the various traits in this disease and indicating the importance of genetic validation for TAR syndrome.
Assuntos
Variação Genética , Hematopoese/genética , Trombocitopenia/genética , Deformidades Congênitas das Extremidades Superiores/genética , Regiões 5' não Traduzidas/genética , Adolescente , Adulto , Criança , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 1/genética , Estudos de Coortes , Síndrome Congênita de Insuficiência da Medula Óssea , Feminino , Humanos , Lactente , Recém-Nascido , Íntrons/genética , Masculino , Contagem de Plaquetas , Polimorfismo de Nucleotídeo Único/genética , Proteínas de Ligação a RNA/genética , Rádio (Anatomia)/patologia , Trombocitopenia/diagnóstico , Trombocitopenia/patologia , Deformidades Congênitas das Extremidades Superiores/diagnóstico , Deformidades Congênitas das Extremidades Superiores/patologia , Adulto JovemRESUMO
BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymatic disorder of red blood cells in human subjects, causing hemolytic anemia linked to impaired nicotinamide adenine dinucleotide phosphate (NADPH) production and imbalanced redox homeostasis in erythrocytes. Because G6PD is expressed by a variety of hematologic and nonhematologic cells, a broader clinical phenotype could be postulated in G6PD-deficient patients. We describe 3 brothers with severe G6PD deficiency and susceptibility to bacterial infection. OBJECTIVE: We sought to study the molecular pathophysiology leading to susceptibility to infection in 3 siblings with severe G6PD deficiency. METHODS: Blood samples of 3 patients with severe G6PD deficiency were analyzed for G6PD enzyme activity, cellular oxidized nicotinamide adenine dinucleotide phosphate/NADPH levels, phagocytic reactive oxygen species production, neutrophil extracellular trap (NET) formation, and neutrophil elastase translocation. RESULTS: In these 3 brothers strongly reduced NADPH oxidase function was found in granulocytes, leading to impaired NET formation. Defective NET formation has thus far been only observed in patients with the NADPH oxidase deficiency chronic granulomatous disease, who require antibiotic and antimycotic prophylaxis to prevent life-threatening bacterial and fungal infections. CONCLUSION: Because severe G6PD deficiency can be a phenocopy of chronic granulomatous disease with regard to the cellular and clinical phenotype, careful evaluation of neutrophil function seems mandatory in these patients to decide on appropriate anti-infective preventive measures. Determining the level of G6PD enzyme activity should be followed by analysis of reactive oxygen species production and NET formation to decide on required antibiotic and antimycotic prophylaxis.
Assuntos
Suscetibilidade a Doenças , Armadilhas Extracelulares/metabolismo , Deficiência de Glucosefosfato Desidrogenase , Infecções Bacterianas , Criança , Eritrócitos/metabolismo , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Deficiência de Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Granulócitos/metabolismo , Humanos , Lactente , Elastase de Leucócito/metabolismo , Masculino , NADP/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Results of a previously published study demonstrated a significant decrease in transfusion requirements and calculated blood loss for pediatric major craniosynostosis surgery, if a ROTEM(®) FIBTEM trigger of <13 mm (early substitution group) was applied as compared to a trigger of <8 mm (conventional group). The aim of this study was a posthoc analysis of the costs for this coagulation management. METHODS: The total volume as well as the number of units or bags for all transfused blood products and coagulation factors were recorded for each case. The number of laboratory and point-of-care coagulation tests was also analyzed. Total blood product costs were calculated according to the local prices per unit. RESULTS: The total cost for all transfused/administered blood products/coagulation factors per patient was a median of 1023EUR (IQR 850EUR-1058EUR) in the early substitution group as compared to a median of 910EUR (IQR 719EUR-1351EUR) in the conventional group (P = 0.81). No difference in the number of coagulation tests performed was observed. CONCLUSION: In this study, the use of a higher fibrinogen trigger was not linked to a significant increase in total costs for transfused blood products and coagulation factors, and may offer an economically equivalent approach to coagulation management.
Assuntos
Fatores de Coagulação Sanguínea/economia , Transfusão de Sangue/economia , Custos e Análise de Custo/estatística & dados numéricos , Craniossinostoses , Fibrinogênio/economia , Cuidados Intraoperatórios/economia , Adolescente , Coagulação Sanguínea/fisiologia , Fatores de Coagulação Sanguínea/administração & dosagem , Transfusão de Sangue/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Fibrinogênio/análise , Hemostáticos , Humanos , Lactente , Cuidados Intraoperatórios/métodos , Masculino , Estudos ProspectivosRESUMO
Germline GATA2 mutations cause cellular deficiencies with high propensity for myeloid disease. We investigated 426 children and adolescents with primary myelodysplastic syndrome (MDS) and 82 cases with secondary MDS enrolled in 2 consecutive prospective studies of the European Working Group of MDS in Childhood (EWOG-MDS) conducted in Germany over a period of 15 years. Germline GATA2 mutations accounted for 15% of advanced and 7% of all primary MDS cases, but were absent in children with MDS secondary to therapy or acquired aplastic anemia. Mutation carriers were older at diagnosis and more likely to present with monosomy 7 and advanced disease compared with wild-type cases. For stratified analysis according to karyotype, 108 additional primary MDS patients registered with EWOG-MDS were studied. Overall, we identified 57 MDS patients with germline GATA2 mutations. GATA2 mutations were highly prevalent among patients with monosomy 7 (37%, all ages) reaching its peak in adolescence (72% of adolescents with monosomy 7). Unexpectedly, monocytosis was more frequent in GATA2-mutated patients. However, when adjusted for the selection bias from monosomy 7, mutational status had no effect on the hematologic phenotype. Finally, overall survival and outcome of hematopoietic stem cell transplantation (HSCT) were not influenced by mutational status. This study identifies GATA2 mutations as the most common germline defect predisposing to pediatric MDS with a very high prevalence in adolescents with monosomy 7. GATA2 mutations do not confer poor prognosis in childhood MDS. However, the high risk for progression to advanced disease must guide decision-making toward timely HSCT.
Assuntos
Fator de Transcrição GATA2/deficiência , Síndromes Mielodisplásicas/genética , Adolescente , Idade de Início , Criança , Pré-Escolar , Aberrações Cromossômicas , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 8/genética , Ensaios Clínicos Fase III como Assunto , Análise Mutacional de DNA , Surdez/genética , Feminino , Fator de Transcrição GATA2/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Síndromes de Imunodeficiência/genética , Estimativa de Kaplan-Meier , Masculino , Síndromes Mielodisplásicas/epidemiologia , Síndromes Mielodisplásicas/etiologia , Síndromes Mielodisplásicas/patologia , Fenótipo , Prevalência , Prognóstico , Estudos Prospectivos , Viés de Seleção , Adulto JovemRESUMO
We report on a series of sequential events leading to long-term survival and cure of pediatric X-linked chronic granulomatous disease (X-CGD) patients after gamma-retroviral gene therapy (GT) and rescue HSCT. Due to therapyrefractory life-threatening infections requiring hematopoietic stem cell transplantation (HSCT) but absence of HLAidentical donors, we treated 2 boys with X-CGD by GT. Following GT both children completely resolved invasive Aspergillus nidulans infections. However, one child developed dual insertional activation of ecotropic viral integration site 1 (EVI1) and signal transducer and activator of transcription 3 (STAT3) genes, leading to myelodysplastic syndrome (MDS) with monosomy 7. Despite resistance to mismatched allo-HSCT with standard myeloablative conditioning, secondary intensified rescue allo-HSCT resulted in 100 % donor chimerism and disappearance of MDS. The other child did not develop MDS despite expansion of a clone with a single insertion in the myelodysplasia syndrome 1 (MDS1) gene and was cured by early standard allo-HSCT. The slowly developing dominance of clones harboring integrations in MDS1-EVI1 may guide clinical intervention strategies, i.e. early rescue allo-HSCT, prior to malignant transformation. GT was essential for both children to survive and to clear therapy-refractory infections, and future GT with safer lentiviral self-inactivated (SIN) vectors may offer a therapeutic alternative for X-CGD patients suffering from life-threatening infections and lacking HLA-identical HSC donors.
Assuntos
Terapia Genética/métodos , Doença Granulomatosa Crônica/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Aspergilose/terapia , Aspergillus nidulans/patogenicidade , Criança , Deleção Cromossômica , Cromossomos Humanos Par 7 , Proteínas de Ligação a DNA/genética , Gammaretrovirus/genética , Terapia Genética/efeitos adversos , Humanos , Proteína do Locus do Complexo MDS1 e EVI1 , Masculino , Glicoproteínas de Membrana/genética , Síndromes Mielodisplásicas/etiologia , NADPH Oxidase 2 , NADPH Oxidases/genética , Proto-Oncogenes/genética , Fator de Transcrição STAT3/genética , Fatores de Transcrição/genéticaAssuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Azacitidina/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Leucemia Mielomonocítica Juvenil/tratamento farmacológico , Síndromes Mielodisplásicas , Criança , Pré-Escolar , Análise Citogenética , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Lactente , Leucemia Mielomonocítica Juvenil/genética , Masculino , Prognóstico , Indução de Remissão , Estudos RetrospectivosRESUMO
Refractory cytopenia of childhood is the most common type of childhood myelodysplastic syndrome. Because the majority of children with refractory cytopenia have a normal karyotype and a hypocellular bone marrow, differentiating refractory cytopenia from the immune-mediated bone marrow failure syndrome (very) severe aplastic anemia can be challenging. Flow cytometric immunophenotyping of bone marrow has been shown to be a valuable diagnostic tool in differentiating myelodysplastic syndrome from non-clonal cytopenias in adults. Here, we performed the first comprehensive flow cytometric analysis of immature myeloid, lymphoid cells and erythroid cells, and granulocytes, monocytes, and lymphoid cells in bone marrow obtained from a large prospective cohort of 81 children with refractory cytopenia. Children with refractory cyotopenia had a strongly reduced myeloid compartment, but not as severe as children with aplastic anemia. Furthermore, the number of flow cytometric abnormalities was significantly higher in children with refractory cytopenia than in healthy controls and in children with aplastic anemia, but lower than in advanced myelodysplastic syndrome. We conclude that flow cytometric immunophenotyping could be a relevant addition to histopathology in the diagnosis of refractory cytopenia of childhood. (The multi-center studies EWOG-MDS RC06 and EWOG-MDS 2006 are registered at clinicaltrials.gov identifiers 00499070 and 00662090, respectively).
Assuntos
Anemia Aplástica/diagnóstico , Medula Óssea/imunologia , Imunofenotipagem , Síndromes Mielodisplásicas/diagnóstico , Pancitopenia/diagnóstico , Adolescente , Anemia Aplástica/imunologia , Anemia Aplástica/patologia , Antígenos CD/imunologia , Medula Óssea/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Células Eritroides/imunologia , Células Eritroides/patologia , Feminino , Citometria de Fluxo , Granulócitos/imunologia , Granulócitos/patologia , Humanos , Lactente , Linfócitos/imunologia , Linfócitos/patologia , Monócitos/imunologia , Monócitos/patologia , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/patologia , Pancitopenia/imunologia , Pancitopenia/patologia , Índice de Gravidade de DoençaRESUMO
Aberrant DNA methylation at specific genetic loci is a key molecular feature of juvenile myelomonocytic leukemia (JMML) with poor prognosis. Using quantitative high-resolution mass spectrometry, we identified RASA4 isoform 2, which maps to chromosome 7 and encodes a member of the GAP1 family of GTPase-activating proteins for small G proteins, as a recurrent target of isoform-specific DNA hypermethylation in JMML (51% of 125 patients analyzed). RASA4 isoform 2 promoter methylation correlated with clinical parameters predicting poor prognosis (older age, elevated fetal hemoglobin), with higher risk of relapse after hematopoietic stem cell transplantation, and with PTPN11 mutation. The level of isoform 2 methylation increased in relapsed cases after transplantation. Interestingly, most JMML cases with monosomy 7 exhibited hypermethylation on the remaining RASA4 allele. The results corroborate the significance of epigenetic modifications in the phenotype of aggressive JMML.