RESUMO
Infections are a leading cause of morbidity and mortality in children with acute leukemia. Central-line (CL) devices increase this population's risk of serious infections.Within the context of a quality improvement (QI) project, we tested the effect of caregiver education on CL management on the CL-associated bloodstream infection (CLABSI) rate among children with acute leukemia seen at a large referral center in Italy. The intervention consisted of 9 in-person sessions for education and practice using mannequins and children.One hundred and twenty caregivers agreed to participate in the initiative. One hundred and five (87.5%) completed the training, 5 (4.1%) withdrew after the first session, and 10 (8.3%) withdrew during practical sessions. After educational intervention, the overall CLABSI rate was reduced by 46% (from 6.86 to 3.70/1000 CL-days). CLABSI rate was lower in children whose caregivers completed the training (1.74/1000 CL-days, 95% CI 0.43-6.94) compared with those who did not receive any training (12.2/1000 CL-days, 95% CI 7.08-21.0, Pâ<â0.05) or were in-training (3.96/1000 CL-days, 95% CI 1.98-7.91) at the time of infection.Caregiver training in CL management, applied within a multifaceted QI approach, reduced the rate of CLABSI in children with acute leukemia. Specific training and active involvement of caregivers in CL management may be effective to reduce CLABSI in high-risk children.
Assuntos
Cuidadores/educação , Infecções Relacionadas a Cateter/epidemiologia , Infecção Hospitalar/epidemiologia , Educação em Saúde/normas , Controle de Infecções/organização & administração , Leucemia/complicações , Melhoria de Qualidade , Infecções Relacionadas a Cateter/etiologia , Cateteres Venosos Centrais/efeitos adversos , Pré-Escolar , Infecção Hospitalar/etiologia , Feminino , Seguimentos , Humanos , Incidência , Itália/epidemiologia , Leucemia/terapia , Masculino , Estudos Retrospectivos , Fatores de TempoRESUMO
The toxicity and efficacy of intrathecal liposomal cytarabine (LC) were evaluated in children with central nervous system (CNS) relapsed/refractory acute leukemia/lymphoma. Thirty patients (male:female ratio 21:9; median age 9.4 years) with CNS relapsed/resistant disease were treated with intrathecal LC at dosages adjusted for age. Twenty-seven (90%) patients simultaneously received systemic chemotherapy, including concurrent high-dose cytarabine or methotrexate in 21 (70%) cases. Of 28 patients evaluable for response, 25 patients (89%) achieved CNS complete remission and three (11%) partial remission. The median number of intrathecal LC administrations per patient was 4. The cerebrospinal fluid was cleared after a median of 3 intrathecal LC administrations. Neurological toxicity ≥ grade 3 occurred in four (13%) patients. No permanent sequelae were observed. The median overall survival was 20.9 months and the 5-year probability of survival was 46%. These encouraging data suggest that intrathecal LC is well tolerated and effective in children with relapsed/refractory CNS leukemia/lymphoma.
Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Citarabina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Injeções Espinhais , Lipossomos , Masculino , Estudos RetrospectivosRESUMO
Hypereosinophilia as first clinical presentation has rarely been reported in paediatric acute lymphoblastic leukaemia. It is commonly associated with specific cytogenetic abnormalities. Although eosinophilia is considered a reactive, non-neoplastic epiphenomenon, it adversely affects patient outcomes, both in children and adults. We describe herewith two paediatric patients who had marked eosinophilia at onset of acute lymphoblastic leukaemia. We point out the importance of a correct differential diagnosis in persistent, unexplained peripheral hypereosinophilia. Clinicians should keep in mind that eosinophilia can be part of the overall pattern of acute leukaemia and therefore needs to be properly investigated. We also provide some recommendations for an appropriate approach to hypereosinophilia - related morbidities.
Assuntos
Eosinofilia/diagnóstico , Predisposição Genética para Doença , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Adolescente , Biópsia por Agulha Fina , Medula Óssea/patologia , Diagnóstico Diferencial , Eosinofilia/sangue , Eosinofilia/etiologia , Feminino , Seguimentos , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnósticoRESUMO
A 9-month-old boy with life-threatening multiresistant pure red cell anemia/autoimmune hemolytic anemia within the frame of a possible, undiagnosed immune-mediated disease was initially treated with prednisone. Further-line therapies of the following 7 relapses included immunoglobulins, rituximab, cyclophosphamide, and alentuzumab followed by other maintenance treatments as cyclosporine, methotrexate, and mycophenolate. After all the administered therapies failed, the patient was successfully treated by splenectomy followed by fludarabine and then sirolimus as maintenance treatment. Relapses might have been caused by the lack of a complete debulking of triggering cells and/or ineffective maintenance therapy. Splenectomy and sirolimus may have played a complementary role in the management of both situations.
Assuntos
Anemia Hemolítica Autoimune/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistência a Medicamentos , Aplasia Pura de Série Vermelha/terapia , Esplenectomia , Anemia Hemolítica Autoimune/diagnóstico , Terapia Combinada , Humanos , Lactente , Masculino , Aplasia Pura de Série Vermelha/diagnóstico , Sirolimo/administração & dosagem , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/análogos & derivadosAssuntos
Linfo-Histiocitose Hemofagocítica/genética , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fenótipo , Prognóstico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
High-dose methotrexate (MTX) is a key component of most treatment protocols for childhood and adolescent non-Hodgkin lymphoma (NHL). Recent studies have suggested that the toxicity of antifolate drugs, such as MTX, is affected by inherited single nucleotide polymorphisms (SNPs) in folate metabolizing genes. The aim of our study was to investigate the potential influence of the C677T and A1298C genetic variants of the methylenetetrahydrofolate reductase (MTHFR) gene on the clinical toxicity and efficacy of MTX in pediatric patients with NHL (n = 95) treated with therapeutic protocols Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) LNH-97 and EURO LB-02. We demonstrated that patients with the 677T genotype had an approximately six-fold greater risk of developing hematological toxicity compared with wild-type carriers, especially in the 1 g/m(2) treatment group (p = 0.01). Moreover, we identified a correlation between the risk of relapse and the T genotype: T carriers had reduced disease-free survival compared with wild-type patients (67% vs. 100%). Our data suggest a pharmacogenetic influence on the adverse effects of high-dose MTX in the 1 g/m(2) treatment group.
Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/genética , Metotrexato/uso terapêutico , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Criança , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/efeitos adversos , Feminino , Genótipo , Humanos , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/mortalidade , Masculino , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo Único , Toxicogenética , Resultado do TratamentoRESUMO
AIM: In the AIEOP-BFM 2000 trial, 15% of pediatric patients treated according to risk-adapted polychemotherapeutic regimens relapsed. The present study aimed to investigate the influence of GST-M1 and GST-T1 deletions on clinical outcome of children with acute lymphoblastic leukemia treated according to the AIEOP-BFM ALL 2000 study protocol. MATERIALS & METHODS: A novel-design, two-phase study was applied to select a subsample of 614 children to be genotyped for the deletions of GST genes. Cumulative incidence of relapse was then estimated by weighted Kaplan-Meier analysis, and the Cox model was applied to evaluate the effect of GST-M1 and GST-T1 isoenzyme deletions on relapse. RESULTS: No overall effect was found, but the GST-M1 deletion was associated with better clinical outcome within prednisone poor-responder patients (hazard ratio [HR]: 0.45; 95% CI: 0.23-0.91; p = 0.026), whereas the GST-T1 deletion was associated with worse outcome in the standard-risk group (HR: 4.62; 95% CI: 1.04-20.6; p = 0.045) and within prednisone good responders (HR: 1.62; 95% CI: 1.02-2.58; p = 0.041). CONCLUSION: Our results show that GST-M1 and GST-T1 homozygous deletions have opposite correlation with relapse, the former being protective and the latter unfavourable in specific subsets of acute lymphoblastic leukemia patients.
Assuntos
Deleção de Genes , Glutationa Transferase/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras , Resultado do Tratamento , Criança , Pré-Escolar , Feminino , Genótipo , Glutationa Transferase/metabolismo , Homozigoto , Humanos , Lactente , Itália , Estimativa de Kaplan-Meier , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Modelos de Riscos Proporcionais , RecidivaRESUMO
Given that the rationale for empirical antifungal therapy in neutropenic children is limited and based on adult patient data, we performed a prospective, randomized, controlled trial that evaluated 110 neutropenic children with persistent fever. Those at high risk for invasive fungal infections (IFI) received caspofungin (Arm C) or liposomal amphotericinB (Arm B); those with a lower risk were randomized to receive Arm B, C, or no antifungal treatment (Arm A). Complete response to empirical antifungal therapy was achieved in 90/104 patients (86·5%): 48/56 at high risk (85·7%) [88·0% in Arm B; 83·9% in Arm C (P = 0·72)], and 42/48 at low risk (87·5%) [87·5% in control Arm A, 80·0% Arm B, 94·1% Arm C; (P = 0·41)]. None of the variables tested by multiple logistic regression analysis showed a significant effect on the probability to achieve complete response. IFI was diagnosed in nine patients (8·2%, 95% confidence interval, 3·8-15·0). This randomized controlled study showed that empirical antifungal therapy was of no advantage in terms of survival without fever and IFI in patients aged <18 years and defined with low risk of IFI. Higher risk patients, including those with relapsed cancer, appear to be the target for empirical antifungal therapy during protracted febrile neutropenia.
Assuntos
Antifúngicos/uso terapêutico , Antineoplásicos/efeitos adversos , Febre de Causa Desconhecida/tratamento farmacológico , Micoses/tratamento farmacológico , Neutropenia/tratamento farmacológico , Anfotericina B/uso terapêutico , Caspofungina , Criança , Pré-Escolar , Equinocandinas/uso terapêutico , Feminino , Febre de Causa Desconhecida/microbiologia , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Tempo de Internação/estatística & dados numéricos , Lipopeptídeos , Masculino , Micoses/induzido quimicamente , Micoses/complicações , Neutropenia/induzido quimicamente , Neutropenia/microbiologia , Infecções Oportunistas/induzido quimicamente , Infecções Oportunistas/tratamento farmacológico , Seleção de Pacientes , Estudos Prospectivos , Resultado do TratamentoRESUMO
The region 21q22 is considered crucial for the pathogenesis of both Down syndrome (DS) and the partial monosomy 21q syndrome. Haploinsufficiency of the RUNX-1 gene, mapping at 21q22 is responsible for a platelet disorder and causes predisposition to myelodysplastic syndrome (MDS). We describe a 3-year-old girl with mental retardation, congenital heart malformation, and subtle dysmorphic facial features. The patient developed thrombocytopenia when she was 2 years old. Bone marrow smear led to the diagnosis of myelodysplasia. Prenatal karyotyping had shown chromosome 21 pericentric inversion. Postnatally the array-CGH revealed duplication at bands 21q11.2-21q21.1 and a simultaneous deletion involving the region 21q22.13-21q22.3. RUNX-1 mRNA levels analyzed in patient's skin fibroblasts were reduced. In this child the monosomy of the region 21q22 likely had the main role in determining the phenotype. Although the RUNX-1 gene is localized outside the deleted region, we speculate that RUNX-1 reduced expression, is probably due to the deletion of regulatory factors and caused the hematologic disorder in the patient. The present report underlines also the importance of array-CGH in characterizing patients with a complex phenotype.
Assuntos
Cromossomos Humanos Par 21/genética , Rearranjo Gênico/genética , Cardiopatias Congênitas/genética , Deficiência Intelectual/genética , Síndromes Mielodisplásicas/genética , Pré-Escolar , Hibridização Genômica Comparativa , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Análise Citogenética , Feminino , Humanos , Monossomia , Fenótipo , RNA Mensageiro/genética , TrissomiaRESUMO
Idiopathic pulmonary hemosiderosis is a chronic, rare disorder confined to the lung, which is commonly characterized by the triad of recurrent hemoptysis, diffuse parenchyma infiltrates on chest radiography, and iron-deficiency anemia. Diagnosis may be difficult and the clinical course may be widely variable. Here, we describe an 8-year-old boy whose isolated symptom on presentation was iron-deficiency anemia. Presence of hemoptysis and bilateral alveolar infiltrates on chest x-ray led to the diagnosis of pulmonary hemosiderosis, subsequently confirmed by the finding of hemosiderin-laden macrophages by bronchoalveolar lavage. The patient was started on prednisolone 2 mg/kg/d and no further bleeding episodes were noted after the onset of therapy.
Assuntos
Anemia Ferropriva/diagnóstico , Anemia Ferropriva/etiologia , Hemossiderose/complicações , Hemossiderose/diagnóstico , Criança , Doença Crônica , Hemoptise/diagnóstico , Hemoptise/etiologia , Humanos , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/etiologia , Masculino , Fibrose Pulmonar/diagnóstico , Fibrose Pulmonar/etiologiaRESUMO
Central nervous system (CNS) complications during treatment of childhood acute lymphoblastic leukemia (ALL) remain a challenging clinical problem. Outcome improvement with more intensive chemotherapy has significantly increased the incidence and severity of adverse events. This study analyzed the incidence of neurological complications during ALL treatment in a single pediatric institution, focusing on clinical, radiological, and electrophysiological findings. Exclusion criteria included CNS leukemic infiltration at diagnosis, therapy-related peripheral neuropathy, late-onset encephalopathy, or long-term neurocognitive defects. During a 9-year period, we retrospectively collected 27 neurological events (11%) in as many patients, from 253 children enrolled in the ALL front-line protocol. CNS complications included posterior reversible leukoencephalopathy syndrome (n = 10), stroke (n = 5), temporal lobe epilepsy (n = 2), high-dose methotrexate toxicity (n = 2), syndrome of inappropriate antidiuretic hormone secretion (n = 1), and other unclassified events (n = 7). In conclusion, CNS complications are frequent events during ALL therapy, and require rapid detection and prompt treatment to limit permanent damage.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Doenças do Sistema Nervoso Central/induzido quimicamente , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Asparaginase/administração & dosagem , Asparaginase/efeitos adversos , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/patologia , Sistema Nervoso Central/fisiopatologia , Doenças do Sistema Nervoso Central/diagnóstico , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Daunorrubicina/administração & dosagem , Daunorrubicina/efeitos adversos , Eletroencefalografia , Feminino , Humanos , Lactente , Infiltração Leucêmica/induzido quimicamente , Infiltração Leucêmica/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Mercaptopurina/administração & dosagem , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/diagnóstico , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Vincristina/administração & dosagem , Vincristina/efeitos adversosRESUMO
The treatment of meningeal relapse in acute lymphoblastic leukemia (ALL) remains a challenging clinical problem. Liposomal cytarabine (DepoCyte) permits to decrease frequency of lumbar punctures, without loss of efficacy, because intrathecal levels of the drug remain cytotoxic for up to 14 days. We investigated the efficacy and safety of intrathecal DepoCyte in six children with meningeal relapse, treated in two pediatric institutions. DepoCyte was well tolerated in all patients, who achieved complete clearance of blasts from the cerebrospinal fluid after the first three intrathecal drug administrations. Five of the six patients were concurrently treated with high-dose administration of systemic cytarabine, without additional neurological side effects. Our results suggest that DepoCyte is a valid option for children with ALL experiencing meningeal relapse; it deserves further investigation in intensive treatment regimens, taking into due consideration potential neurotoxicity.
Assuntos
Citarabina/administração & dosagem , Injeções Espinhais , Neoplasias Meníngeas/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Antimetabólitos Antineoplásicos , Líquido Cefalorraquidiano , Criança , Pré-Escolar , Citarabina/toxicidade , Portadores de Fármacos , Avaliação de Medicamentos , Feminino , Humanos , Lactente , Lipossomos , Masculino , Neoplasias Meníngeas/etiologia , Recidiva , Resultado do TratamentoAssuntos
Infecções por Helicobacter/complicações , Helicobacter pylori , Púrpura Trombocitopênica Idiopática/complicações , Adolescente , Criança , Pré-Escolar , Feminino , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Contagem de Plaquetas , Púrpura Trombocitopênica Idiopática/imunologiaRESUMO
The 911 amino acid band 3 (SLC4A1) is the major intrinsic membrane protein of red cells and is the principal Cl-/HCO3- exchanger. The N-terminal cytoplasmic domain of band 3 anchors the spectrin-based membrane skeleton to the lipid bilayer through its interaction with ankyrin and also binds glycolytic enzymes and hemoglobin. We identified a son of a consanguineous marriage with severe anemia in association with marked deficiency of band 3 (12% +/- 4% of normal). Direct nucleotide sequencing of SLC4A1 gene demonstrated a single base substitution (T --> C) at position + 2 in the donor splice site of intron 2, resulting in the generation of a novel mutant protein. Biochemical characterization of the mutant protein showed that it lacked the first 11 N-terminal amino acids (band 3 Neapolis). The expression of the mutant protein resulted in the complete absence of membrane-bound aldolase, and the mutant band 3 could not be tyrosine phosphorylated. The ability of the malarial parasite P falciparum to invade these red cells was significantly decreased. The identification of a novel band 3 mutant and its structural and functional characterization enabled us to identify pivotal roles for the 11 N-terminal amino acids in several protein functions and, in turn, in red-cell physiology.
Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Sequência de Aminoácidos , Animais , Proteína 1 de Troca de Ânion do Eritrócito/química , Proteína 1 de Troca de Ânion do Eritrócito/genética , Sequência de Bases , Membrana Eritrocítica/química , Membrana Eritrocítica/genética , Membrana Eritrocítica/metabolismo , Eritrócitos/química , Eritrócitos/metabolismo , Glucose/metabolismo , Homozigoto , Humanos , Dados de Sequência Molecular , Mutação/genética , Fosforilação , Plasmodium falciparum/fisiologia , Ligação Proteica , Splicing de RNA/genética , RNA Mensageiro/genéticaRESUMO
The phosphatidyl-inositol 3 kinase (PI3k)/Akt pathway has been implicated in childhood acute lymphoblastic leukemia (ALL). Because rapamycin suppresses the oncogenic processes sustained by PI3k/Akt, we investigated whether rapamycin affects blast survival. We found that rapamycin induces apoptosis of blasts in 56% of the bone marrow samples analyzed. Using the PI3k inhibitor wortmannin, we show that the PI3k/Akt pathway is involved in blast survival. Moreover, rapamycin increased doxorubicin-induced apoptosis even in nonresponder samples. Anthracyclines activate nuclear factor kappaB (NF-kappaB), and disruption of this signaling pathway increases the efficacy of apoptogenic stimuli. Rapamycin inhibited doxorubicin-induced NF-kappaB in ALL samples. Using a short interfering (si) RNA approach, we demonstrate that FKBP51, a large immunophilin inhibited by rapamycin, is essential for drug-induced NF-kappaB activation in human leukemia. Furthermore, rapamycin did not increase doxorubicin-induced apoptosis when NF-kappaB was overexpressed. In conclusion, rapamycin targets 2 pathways that are crucial for cell survival and chemoresistance of malignant lymphoblasts--PI3k/Akt through the mammalian target of rapamycin and NF-kappaB through FKBP51--suggesting that the drug could be beneficial in the treatment of childhood ALL.
Assuntos
Apoptose/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Transdução de Sinais , Sirolimo/farmacologia , Adolescente , Crise Blástica/tratamento farmacológico , Crise Blástica/patologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Criança , Pré-Escolar , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Feminino , Humanos , Lactente , Masculino , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Proteínas de Ligação a Tacrolimo/metabolismo , Células Tumorais CultivadasRESUMO
The minimum spanning tree (MST) model was applied to identify the history of transmission of hepatitis C virus (HCV) infection in an outbreak involving five children attending a pediatric oncology-hematology outpatient ward between 1992 and 2000. We collected blood samples from all children attending since 1992, all household contacts, and one health care worker positive for antibody to HCV (anti-HCV). HCV RNA detection was performed with these samples and with smears of routinely collected bone marrow samples. For all isolates, we performed sequence analysis and phylogenetic tree analysis of hypervariable region 1 of the E2 gene. The MST model was applied to clinical-epidemiological and molecular data. No additional cases were detected. All children, but not the health care worker, showed genotype 3a. On six occasions, all but one child had shared the medication room with another patient who later seroconverted. HCV RNA detection in bone marrow smears revealed, in some cases, a delay of several months in anti-HCV responses. Sequence analysis and phylogenetic tree analysis revealed a high identity among the isolates. The MST model applied to molecular data, together with the clinical-epidemiological data, allowed us to identify the source of the outbreak and the most probable patient-to-patient chain of transmission. The management of central venous catheters was suspected to be the probable route of transmission. In conclusion, the MST model, supported by an exhaustive clinical-epidemiological investigation, appears to be a useful tool in tracing the history of transmission in outbreaks of HCV infection.
Assuntos
Infecção Hospitalar/epidemiologia , Surtos de Doenças , Hepacivirus/genética , Hepatite C/epidemiologia , Criança , Feminino , Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Hepatite C/transmissão , Humanos , Pacientes Internados , Itália/epidemiologia , Masculino , Modelos Teóricos , Epidemiologia Molecular , Pacientes Ambulatoriais , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificaçãoRESUMO
The transcription factor GATA-1, together with its cofactor FOG-1, regulates erythropoiesis and megakaryocytopoiesis. Mutations in the DNA or FOG-1 binding sites of its N-terminal zinc finger result in different illnesses. Alterations of the FOG-1 face are responsible for dyserythropoietic anemia with thrombocytopenia while R216Q, the only mutation identified in the DNA face, induces X-linked thrombocytopenia with thalassemia (XLTT). The former disorder has been studied in detail whereas little is known about the latter since only one family has been investigated. We studied a second family with an R216Q, showing that XLTT and dyserythropoietic anemia with thrombocytopenia, even if different clinical entities, are closely related disorders. In both cases, patients present mild dyserythropoiesis, red cell hemolysis, severely defective maturation of megakaryocytes, macrothrombocytopenia with alpha-granule deficiency, and abnormalities of the cytoplasmic membrane system. However, a thalassemia minor phenotype has only been described in patients with XLTT whereas severe anemia and thrombocytopenia with evident defects of platelet composition and function may be observed only in dyserythropoietic anemia with thrombocytopenia.
Assuntos
Proteínas de Ligação a DNA/genética , Eritropoese/genética , Mutação , Trombopoese/genética , Fatores de Transcrição/genética , Sítios de Ligação , Medula Óssea/metabolismo , Células da Medula Óssea/metabolismo , Criança , Cromossomos Humanos X/genética , Citoplasma/metabolismo , DNA/metabolismo , Análise Mutacional de DNA , Fatores de Ligação de DNA Eritroide Específicos , Saúde da Família , Feminino , Citometria de Fluxo , Fator de Transcrição GATA1 , Ligação Genética , Globinas/química , Hemólise , Humanos , Masculino , Megacariócitos/metabolismo , Microscopia Eletrônica , Microscopia de Fluorescência , Linhagem , Fenótipo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Estrutura Terciária de Proteína , Talassemia/genética , Trombocitopenia/genética , Dedos de ZincoAssuntos
Proteínas de Transporte/fisiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Apoptose , Proteínas Reguladoras de Apoptose , Proteínas de Transporte/antagonistas & inibidores , Sobrevivência Celular , Criança , Pré-Escolar , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Masculino , Oligonucleotídeos Antissenso/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologiaRESUMO
In Fanconi anemia (FA) C mice tumor necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) have key roles in the pathogenesis of bone marrow failure. In FA subjects TNF-alpha was found to be increased in the serum and overproduced by patient-derived B-cell lines. In acquired aplastic anemia, a disease in which, similarly to FA, marrow failure occurs, TNF-alpha and IFN-gamma act as late mediators of the stem cell damage and are overexpressed in patient marrow lymphocytes. This study evaluated in marrow mononuclear cells (MNCs) of patients with FA, the expression of negative modulators of the hematopoiesis, such as TNF-alpha, IFN-gamma, macrophage inflammatory protein 1alpha (MIP-1alpha), and surface Fas ligand, and the role of TNF-alpha on FA erythropoiesis in vitro. TNF-alpha and IFN-gamma were significantly overexpressed in stimulated marrow MNCs of FA patients as compared to healthy controls. MIP-1alpha and Fas ligand were undetectable in patients and controls. In bone marrow cultures, the addition of anti-TNF-alpha increased the size and significantly increased the number of erythroid colony-forming units and erythroid burst-forming units grown from FA patients but not from healthy controls. This indicates that FA subjects have a marrow TNF-alpha activity that inhibits erythropoiesis in vitro. TNF-alpha has a relevant role in the pathogenesis of erythroid failure in FA patients.