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1.
J Allergy Clin Immunol Pract ; 8(1): 273-282, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31377437

RESUMO

BACKGROUND: Rituximab (RTX; anti-CD20 mAb) is a treatment option in children with refractory immune thrombocytopenia, autoimmune hemolytic anemia (AHA), and Evans syndrome (ES). Prevalence and clinical course of RTX-induced hypogammaglobulinemia in these patients are poorly known. OBJECTIVE: To evaluate the prevalence and risk factors for persistent hypogammaglobulinemia (PH) after RTX use. METHODS: Clinical and immunologic data from children treated with RTX for immune thrombocytopenia, AHA, and ES were collected from 16 Italian centers and 1 UK center at pre-RTX time point (0), +6 months, and yearly, up to 4 years post-RTX. Patients with previously diagnosed malignancy or primary immune deficiency (PID) were excluded. RESULTS: We analyzed 53 children treated with RTX for immune thrombocytopenia (n = 36), AHA (n = 13), and ES (n = 4). Median follow-up was 30 months (range, 12-48). Thirty-two percent of patients (17 of 53) experienced PH, defined as IgG levels less than 2 SD for age at last follow-up (>12 months after RTX). Significantly delayed B-cell recovery was observed in children experiencing PH (hazard ratio, 0.55; P < .05), and 6 of 17 (35%) patients had unresolved B-cell lymphopenia at last follow-up. PH was associated with IgA and IgM deficiency, younger age at RTX use (51 vs 116 months; P < .01), a diagnosis of AHA/ES, and better response to RTX. Nine patients with PH (9 of 17 [53%]) were eventually diagnosed with a PID. CONCLUSIONS: Post-RTX PH is a frequent condition in children with autoimmune cytopenia; a sizable proportion of patients with post-RTX PH were eventually diagnosed with a PID. In-depth investigation for PID is therefore recommended in these patients.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31876783

RESUMO

In recent years, monogenic causes of immune dysregulation syndromes, with variable phenotypes, have been documented. Mutations in the lipopolysaccharide-responsive beige-like anchor (LRBA) protein are associated with common variable immunodeficiency, autoimmunity, chronic enteropathy, and immune dysregulation disorders. The LRBA protein prevents degradation of cytotoxic T-lymphocyte antigen 4 (CTLA4) protein, thus inhibiting immune responses. Both LRBA and CTLA4 deficiencies usually present with immune dysregulation, mostly characterized by autoimmunity and lymphoproliferation. In this report, we describe a patient with an atypical clinical onset of LRBA deficiency and the patient's response to abatacept, a fusion protein-drug that mimics the action of CTLA4.

3.
Blood ; 134(Supplement_1): 44, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31724018

RESUMO

DISCLOSURES: Bader: Riemser, Neovii: Research Funding; Medac: Patents & Royalties, Research Funding; Amgen (Brasil), Novartis: Consultancy, Speakers Bureau; Celgene: Consultancy. Risitano:Alexion: Honoraria, Research Funding, Speakers Bureau; Achillion: Research Funding; Apellis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Apellis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Biocryst: Membership on an entity's Board of Directors or advisory committees; Alexion: Honoraria, Research Funding, Speakers Bureau; Amyndas: Consultancy; Samsung: Membership on an entity's Board of Directors or advisory committees; Samsung: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amyndas: Consultancy; Biocryst: Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Ra Pharma: Research Funding; Ra Pharma: Research Funding; Alnylam: Research Funding; Alnylam: Research Funding; Achillion: Research Funding. Peffault de Latour:Pfizer: Consultancy, Honoraria, Research Funding; Amgen: Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Alexion: Consultancy, Honoraria, Research Funding.

4.
Br J Haematol ; 187(4): 502-508, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31309545

RESUMO

Autoimmune lymphoproliferative syndrome (ALPS) is a congenital disorder that results in an apoptosis impairment of lymphocytes, leading to chronic lymphoproliferation and autoimmunity, mainly autoimmune cytopenias. FAS gene defects are often responsible for the disease, the phenotype of which can vary from asymptomatic/mild forms to severe disease. More rarely, defects are associated to  other genes involved in apoptosis pathway, such as CASP10. Few data are available on CASP10-mutated patients. To date, two CASP10 mutations have been recognized as pathogenic (I406L and L258F) and others have been reported with controversial result on their pathogenicity (V410l, Y446C) or are known to be polymorphic variants (L522l). In this study, we evaluated apoptosis function in patients with an ALPS/ALPS-like phenotype carrying CASP10 variants. Molecular findings were obtained by next generation sequencing analysis of genes involved in immune dysregulation syndromes. Functional studies were performed after inducing apoptosis by FAS-ligand/TRIAL stimulation and analysing cell death and the function of CASP10, CASP8 and PARP proteins. We identified 6 patients with an ALPS (n = 2) or ALPS-like (n = 4) phenotype, carrying I406L (n = 1),V410l (n = 2),Y446C (n = 1) heterozygous CASP10 variants or the L522l polymorphisms (n = 2) associated with another polymorphic homozygote variant on CASP8 or a compound heterozygous mutation on TNFRSF13C. Apoptosis was impaired in all patients showing that such variants may play a role in the development of clinical phenotype.

8.
Front Immunol ; 9: 1761, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30131802

RESUMO

Mutations in genes that control class switch recombination and somatic hypermutation during the germinal center (GC) response can cause diverse immune dysfunctions. In particular, mutations in CD40LG, CD40, AICDA, or UNG cause hyper-IgM (HIGM) syndrome, a heterogeneous group of primary immunodeficiencies. Follicular helper (Tfh) and follicular regulatory (Tfr) T cells play a key role in the formation and regulation of GCs, but their role in HIGM pathogenesis is still limited. Here, we found that compared to CD40 ligand (CD40L)- and activation-induced cytidine deaminase (AICDA)-deficient patients, circulating Tfh and Tfr cells were severely compromised in terms of frequency and activation phenotype in a child with CD40 deficiency. These findings offer useful insight for human Tfh biology, with potential implications for understanding the molecular basis of HIGM syndrome caused by mutations in CD40.


Assuntos
Antígenos CD40/deficiência , Síndrome de Imunodeficiência com Hiper-IgM/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Antígenos CD40/genética , Ligante de CD40/genética , Pré-Escolar , Citidina Desaminase/deficiência , Citidina Desaminase/genética , Feminino , Humanos , Síndrome de Imunodeficiência com Hiper-IgM/genética , Imunofenotipagem , Ativação Linfocitária , Masculino , Mutação , Adulto Jovem
9.
Br J Haematol ; 183(1): 110-118, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29984823

RESUMO

Dyskeratosis congenita (DC) is a genetic multisystem disorder with frequent involvement of the bone marrow. Haematopoietic stem cell transplantation (HSCT) is the only definitive cure to restore haematopoiesis, even though it cannot correct other organ dysfunctions. We collected data on the outcome of HSCT in the largest cohort of DC (n = 94) patients ever studied. Overall survival (OS) and event-free survival (EFS) at 3 years after HSCT were 66% and 62%, respectively. Multivariate analysis showed better outcomes in patients aged less than 20 years and in patients transplanted from a matched, rather than a mismatched, donor. OS and EFS curves tended to decline over time. Early lethal events were infections, whereas organ damage and secondary malignancies appeared afterwards, even a decade after HSCT. A non-myeloablative conditioning regimen appeared to be most advisable. Organ impairment present before HSCT seemed to favour the development of chronic graft-versus-host disease and T-B immune deficiency appeared to enhance pulmonary fibrosis. According to the present data, HSCT in DC is indicated in cases of progressive marrow failure, whereas in patients with pre-existing organ damage, this should be carefully evaluated. Further efforts to investigate treatment alternatives to HSCT should be encouraged.


Assuntos
Disceratose Congênita/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adulto , Fatores Etários , Doenças da Medula Óssea/etiologia , Disceratose Congênita/complicações , Disceratose Congênita/mortalidade , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Fibrose Pulmonar/etiologia , Análise de Sobrevida , Doadores de Tecidos , Condicionamento Pré-Transplante/métodos , Resultado do Tratamento , Adulto Jovem
13.
Pediatr Blood Cancer ; 65(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28868627

RESUMO

BACKGROUND: The number of patients with sickle cell disease (SCD) has increased in Italy in the past decade due to immigration. In spite of the established efficacy of hydroxyurea (HU) in childhood, population-based data regarding its prescription and effectiveness come mainly from studies performed in adults or outside Europe. POPULATION AND METHODS: The Hydroxyurea in SCD: A Large Nation-wide Cohort Study from Italy was a retrospective cohort study of adult and pediatric patients with SCD attending 32 centers. Pediatric data are analyzed separately. RESULTS: Out of 504 children followed in 11 centers, 206 (40%) were on HU (194 SS/Sß°, 12 SC/Sß+); 74% came from Sub-Saharian Africa and 18% from Europe. HU therapy indications for SS/Sß° patients were as follows: 57% painful vaso-occlusive crisis, acute chest syndrome or both, 24% anemia, 8% anemia, and other reasons (the majority had Hb ≤ 8-8.5 g/dl, revealing scarce acceptance of low Hb values by pediatric hematologist). Mean starting dose was 15.5 mg/kg, and dose at full regimen was 17.1 mg/kg. Mean age at HU therapy was 7.68 years, although it was lower for SS/Sß° patients. Only 10% started HU before 3 years. In 92%, 500 mg capsule was used; in 6%, the galenic was used; and in 2%, 100 mg tablet was used. Significant reduction of clinical events and inpatients admissions, with improvement in hematological parameters, was observed for SS/Sß° patients and a trend toward improvement for SC/Sß+ patients was also observed. CONCLUSIONS: HU effectiveness is demonstrated in a national cohort of children with SCD living in Italy, even at a lower dose than recommended, revealing good adherence to a treatment program by a socially vulnerable group of patients such as immigrants.


Assuntos
Anemia Falciforme/tratamento farmacológico , Prescrições de Medicamentos , Acesso aos Serviços de Saúde , Hidroxiureia/administração & dosagem , Adolescente , Anemia Falciforme/epidemiologia , Criança , Pré-Escolar , Emigrantes e Imigrantes , Feminino , Seguimentos , Humanos , Lactente , Itália/epidemiologia , Masculino
14.
Exp Clin Transplant ; 2017 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-28969530

RESUMO

Dyskeratosis congenita is a rare congenital telomeropathy characterized by cutaneous and nail dystrophy, oral leukoplakia, and bone marrow failure. Pulmonary fibrosis and cancers are late manifestations. Allogeneic hematopoietic stem cell transplant represents the only cure for those with bone marrow failure with this disease, but outcomes reported are overall poor, with organ toxicities, graft failure, and graft-versus-host disease as main issues. Although reduced intensity conditioning regimens seem to be related to better outcomes, a standard regimen for dyskeratosis congenita has never been defined. Here, we report a successful long-term outcome of an 8-year-old girl with dyskeratosis congenita who received 2 consecutive allogeneic hematopoietic stem cell transplants from different unrelated donors, because of rejection after the first one, both conditioned with fludarabine-based reduced intensity conditioning regimen. The second transplant was complicated by severe hemorrhagic cystitis and acute grade IV graft-versus-host disease in the early phase and mild chronic graft-versus-host disease and ureteral stenosis in the late phase. This experience confirms that dyskeratosis congenita is at high risk for transplant-related morbidity but that a fludarabine-based reduced intensity conditioning regimen is a safe and feasible option as a preparative regimen, as shown here in a second transplant after first graft rejection. To reduce the risk of graft-versus-host disease, more effective prophylaxis schedules should be chosen in cases of unrelated donor, and haploidentical hematopoietic stem cell transplant with in vitro α/ ß + and CD19+ depletion should be considered.

15.
Biochim Biophys Acta Mol Basis Dis ; 1863(6): 1214-1221, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28315453

RESUMO

Energetic metabolism plays an essential role in the differentiation of haematopoietic stem cells (HSC). In Fanconi Anaemia (FA), DNA damage is accumulated during HSC differentiation, an event that is likely associated with bone marrow failure (BMF). One of the sources of the DNA damage is altered mitochondrial metabolism and an associated increment of oxidative stress. Recently, altered mitochondrial morphology and a deficit in the energetic activity in FA cells have been reported. Considering that mitochondria are the principal site of aerobic ATP production, we investigated FA metabolism in order to understand what pathways are able to compensate for this energy deficiency. In this work, we report that the impairment in mitochondrial oxidative phosphorylation (OXPHOS) in FA cells is countered by an increase in glycolytic flux. By contrast, glutaminolysis appears lower with respect to controls. Therefore, it is possible to conclude that in FA cells glycolysis represents the main pathway for producing energy, balancing the NADH/NAD+ ratio by the conversion of pyruvate to lactate. Finally, we show that a forced switch from glycolytic to OXPHOS metabolism increases FA cell oxidative stress. This could be the cause of the impoverishment in bone marrow HSC during exit from the homeostatic quiescent state. This is the first work that systematically explores FA energy metabolism, highlighting its flaws, and discusses the possible relationships between these defects and BMF.


Assuntos
Anemia de Fanconi/metabolismo , Glicólise , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Estresse Oxidativo , Linhagem Celular , Anemia de Fanconi/patologia , Humanos , Mitocôndrias/patologia
16.
Blood Transfus ; 15(3): 259-267, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28151390

RESUMO

Autoimmune haemolytic anaemia is an uncommon disorder to which paediatric haematology centres take a variety of diagnostic and therapeutic approaches. The Red Cell Working Group of the Italian Association of Paediatric Onco-haematology (Associazione Italiana di Ematologia ed Oncologia Pediatrica, AIEOP) developed this document in order to collate expert opinions on the management of newly diagnosed childhood autoimmune haemolytic anaemia.The diagnostic process includes the direct and indirect antiglobulin tests; recommendations are given regarding further diagnostic tests, specifically in the cases that the direct and indirect antiglobulin tests are negative. Clear-cut definitions of clinical response are stated. Specific recommendations for treatment include: dosage of steroid therapy and tapering modality for warm autoimmune haemolytic anaemia; the choice of rituximab as first-line therapy for the rare primary transfusion-dependent cold autoimmune haemolytic anaemia; the indications for supportive therapy; the need for switching to second-line therapy. Each statement is provided with a score expressing the level of appropriateness and the agreement among participants.


Assuntos
Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/terapia , Anemia Hemolítica Autoimune/induzido quimicamente , Anemia Hemolítica Autoimune/epidemiologia , Transfusão de Sangue/métodos , Criança , Teste de Coombs/métodos , Gerenciamento Clínico , Hematologia/métodos , Humanos , Imunoglobulina M/análise , Itália/epidemiologia , Pediatria/métodos , Sociedades Médicas , Esteroides/uso terapêutico
18.
Br J Haematol ; 175(3): 490-495, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27447678

RESUMO

Mycophenolate mofetil (MMF) has been shown to be effective in children with immune thrombocytopenia (ITP) and Evans syndrome (ES), but data from larger series and details on the timing of the response are lacking. We evaluated 56 children treated with MMF for ITP (n = 40) or ES (n = 16), which was primary or secondary to autoimmune lymphoproliferative syndrome -related syndrome (ARS). Thirty-five of the 54 evaluable patients (65%) achieved a partial (18%) or complete (46%) response after a median (range) of 20 (7-137) and 37 (7-192) d, respectively. ITP and ES patients responded in 58% and 81% of cases (P = not significant, ns), with complete response in 32% and 81% (P = 0·01), respectively. 60% and 73% of children with primary disease and ARS responded (P = ns) with complete response in 34% and 68% of cases (P = 0·01), respectively. Six of 35 (17%) children relapsed after a median of 283 d (range 189-1036). Limited toxicity was observed in four patients. The median durations of treatment and follow-up were seven and 12·7 months, respectively. This is the largest reported cohort of patients treated with MMF for ITP/ES. The results show that MMF is effective and safe and provides a relatively quick response, suggesting that it has a potential role as an alternative to more aggressive and expensive second/further-line treatments.


Assuntos
Anemia Hemolítica Autoimune/tratamento farmacológico , Antibióticos Antineoplásicos/uso terapêutico , Ácido Micofenólico/uso terapêutico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Trombocitopenia/tratamento farmacológico , Adolescente , Anemia Hemolítica Autoimune/diagnóstico , Antibióticos Antineoplásicos/efeitos adversos , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Itália , Masculino , Ácido Micofenólico/efeitos adversos , Razão de Chances , Púrpura Trombocitopênica Idiopática/diagnóstico , Recidiva , Retratamento , Estudos Retrospectivos , Trombocitopenia/diagnóstico , Resultado do Tratamento
19.
Blood ; 128(2): 227-38, 2016 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-27099149

RESUMO

Autoimmune lymphoproliferative syndrome (ALPS) is a human disorder characterized by defective Fas signaling, resulting in chronic benign lymphoproliferation and accumulation of TCRαß(+) CD4(-) CD8(-) double-negative T (DNT) cells. Although their phenotype resembles that of terminally differentiated or exhausted T cells, lack of KLRG1, high eomesodermin, and marginal T-bet expression point instead to a long-lived memory state with potent proliferative capacity. Here we show that despite their terminally differentiated phenotype, human ALPS DNT cells exhibit substantial mitotic activity in vivo. Notably, hyperproliferation of ALPS DNT cells is associated with increased basal and activation-induced phosphorylation of serine-threonine kinases Akt and mechanistic target of rapamycin (mTOR). The mTOR inhibitor rapamycin abrogated survival and proliferation of ALPS DNT cells, but not of CD4(+) or CD8(+) T cells in vitro. In vivo, mTOR inhibition reduced proliferation and abnormal differentiation by DNT cells. Importantly, increased mitotic activity and hyperactive mTOR signaling was also observed in recently defined CD4(+) or CD8(+) precursor DNT cells, and mTOR inhibition specifically reduced these cells in vivo, indicating abnormal programming of Fas-deficient T cells before the DNT stage. Thus, our results identify the mTOR pathway as a major regulator of lymphoproliferation and aberrant differentiation in ALPS.


Assuntos
Síndrome Linfoproliferativa Autoimune/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/imunologia , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/imunologia , Adolescente , Adulto , Síndrome Linfoproliferativa Autoimune/patologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lectinas Tipo C/imunologia , Antígenos Comuns de Leucócito/imunologia , Masculino , Proteínas Proto-Oncogênicas c-akt/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transativadores/imunologia
20.
Br J Haematol ; 172(4): 524-34, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26625877

RESUMO

The management of Evans Syndrome in children is challenging due to the lack of evidence-based data on treatment. Steroids, the first-choice therapy, are successful in about 80% of cases. For children who are resistant, relapse or become steroid-dependent, rituximab is considered a valid second-line treatment, with the exception of those with an underlying diagnosis of autoimmune lymphoproliferative syndrome who may benefit from other options such as mycophenolate mofetil and sirolimus. Better knowledge of the immunological mechanisms underlying cytopenias and the availability of new immunosuppressive drugs can be helpful in the choice of more targeted therapies that would enable the reduction of the use of long-term steroid administration or other more aggressive options, such as splenectomy or stem cell transplantation. This manuscript provides an overview of the pathogenic background of the disease, and suggests a clinical approach to diagnosis and treatment with a particular focus on the management of relapsing/resistant disease.


Assuntos
Anemia Hemolítica Autoimune/terapia , Fatores Imunológicos/uso terapêutico , Trombocitopenia/terapia , Alemtuzumab , Anemia Hemolítica Autoimune/diagnóstico , Anticorpos Monoclonais Humanizados/uso terapêutico , Bortezomib/uso terapêutico , Criança , Ciclofosfamida/uso terapêutico , Ciclosporina/uso terapêutico , Resistência a Medicamentos , Transfusão de Eritrócitos/métodos , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Imunossupressores/uso terapêutico , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Recidiva , Rituximab/uso terapêutico , Sirolimo/uso terapêutico , Esplenectomia/métodos , Transplante de Células-Tronco/métodos , Esteroides/uso terapêutico , Trombocitopenia/diagnóstico
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