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1.
Br J Haematol ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566733

RESUMO

Viral respiratory infections (VRIs) contribute to the morbidity and transplant-related mortality (TRM) after allogeneic haematopoietic stem cell transplantation (HSCT) and strategies to prevent and treat VRIs are warranted. We monitored VRIs before and after transplant in children undergoing allogeneic HSCT with nasopharyngeal aspirates (NPA) and assessed the impact on clinical outcome. Between 2007 and 2017, 585 children underwent 620 allogeneic HSCT procedures. Out of 75 patients with a positive NPA screen (12%), transplant was delayed in 25 cases (33%), while 53 children started conditioning with a VRI. Patients undergoing HSCT with a positive NPA screen had a significantly lower overall survival (54% vs. 79%) and increased TRM (26% vs. 7%) compared to patients with a negative NPA. Patients with a positive NPA who delayed transplant and cleared the virus before conditioning had improved overall survival (90%) and lower TRM (5%). Pre-HSCT positive NPA was the only significant risk factor for progression to a lower respiratory tract infection and was a major risk factor for TRM. Transplant delay, whenever feasible, in case of a positive NPA screen for VRIs can positively impact on survival of children undergoing HSCT.

2.
Expert Rev Clin Immunol ; 15(7): 735-751, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31070946

RESUMO

Introduction: Adequate immune reconstitution post-HSCT is crucial for the success of transplantation, and can be affected by both patient- and transplant-related factors. Areas covered: A systematic literature search in PubMed, Scopus, and abstracts of international congresses is performed to investigate immune recovery posttransplant. In this review, we discuss the pattern of immune recovery in the post-transplant period focusing on the impact of stem cell source (bone marrow, peripheral blood stem cells, and cord blood) on immune recovery and HSCT outcome. We examine the impact of serotherapy on immune reconstitution and the need to tailor dosing of serotherapy agents when using different stem cell sources. We discuss new techniques being used particularly with cord blood and haploidentical grafts to improve immune recovery in each scenario. Expert opinion: Cord blood T cells provide a unique CD4+ biased immune reconstitution. Initial studies using targeted serotherapy with cord grafts showed improved immune recovery with limited alloreactivity. Two competing haploidentical approaches have developed in recent years including TCRαß/CD19 depleted grafts and post-cyclophosphamide haplo-HSCT. Both approaches have comparable survival rates with limited alloreactivity. However, delayed immune reconstitution is still an ongoing problem and could be improved by modified donor lymphocyte infusions from the same haploidentical donor.

3.
Blood Adv ; 3(7): 1118-1128, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30952678

RESUMO

When hematopoietic stem cell transplant (HSCT) is necessary for children with acute myeloid leukemia (AML), there remains debate about the best stem cell source. Post-HSCT relapse is a common cause of mortality, and complications such as chronic graft versus host disease (cGVHD) are debilitating and life-threatening. To compare post-HSCT outcomes of different donor sources, we retrospectively analyzed consecutive transplants performed in several international centers from 2005 to 2015. A total of 317 patients were studied: 19% matched sibling donor (MSD), 23% matched unrelated donor (MUD), 39% umbilical cord blood (UCB), and 19% double UCB (dUCB) recipients. The median age at transplant was 10 years (range, 0.42-21 years), and median follow-up was 4.74 years (range, 4.02-5.39 years). Comparisons were made while controlling for patient, transplant, and disease characteristics. There were no differences in relapse, leukemia-free survival, or nonrelapse mortality. dUCB recipients had inferior survival compared with matched sibling recipients, but all other comparisons showed similar overall survival. Despite the majority of UCB transplants being HLA mismatched, the rates of cGVHD were low, especially compared with the well-matched MUD recipients (hazard ratio, 0.3; 95% confidence interval, 0.14-0.67; P = .02). The composite measure of cGVHD and leukemia-free survival (cGVHD-LFS), which represents both the quality of life and risk for mortality, was significantly better in the UCB compared with the MUD recipients (HR, 0.56; 95% confidence interval, 0.34-1; P = .03). In summary, the use of UCB is an excellent donor choice for pediatric patients with AML when a matched sibling cannot be identified.

4.
J Pediatr ; 209: 97-106.e2, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30850087

RESUMO

OBJECTIVES: To investigate effects and outcome of hematopoietic stem cell transplantation (HSCT) on sclerosing cholangitis, in pediatric patients with different primary immunodeficiencies (PIDs). STUDY DESIGN: From databases in 2 tertiary centers for immunodeficiencies and liver disease, we have identified children with PIDs and sclerosing cholangitis, who have paired clinical, radiologic, and histologic information before and after HSCT and studied their clinical progress and outcome. RESULTS: Seven of 13 children (53.8%) died at a median interval of 4 months (range, 3 months-5 years) after HSCT. However, 6 surviving children (46.2%) with different PIDs and less severe cholangiopathies showed an improvement in markers of liver injury within months of successful unrelated reduced intensity conditioning HSCT. The repeated native liver biopsy, performed in 4 patients at a median of 96 (range, 4-144) months post-HSCT, showed a considerable improvement. Biochemical markers of liver function in the survivors completely normalized after a median of 13 months (range, 2-48). All patients continue to have a mildly dilated extrahepatic biliary system on ultrasonography with no intrahepatic ductal changes on magnetic resonance cholangiography after a follow-up of median 18 years (range, 2-20). CONCLUSIONS: Effective HSCT has the potential to improve biochemical and histologic features of cholangiopathy in children with PIDs, presumably by clearance of chronic infection following establishment of immune competence. However, careful patient selection is critical as advanced liver injury is often associated with serious complications and mortality.

5.
J Allergy Clin Immunol ; 144(1): 280-293, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30731121

RESUMO

BACKGROUND: Mismatched stem cell transplantation is associated with a high risk of graft loss, graft-versus-host disease (GvHD), and transplant-related mortality. Alternative graft manipulation strategies have been used over the last 11 years to reduce these risks. OBJECTIVE: We investigated the outcome of using different graft manipulation strategies among children with primary immunodeficiencies. METHODS: Between 2006 and 2017, 147 patients with primary immunodeficiencies received 155 mismatched grafts: 30 T-cell receptor (TCR) αß/CD19-depleted grafts, 43 cord blood (CB) grafts (72% with no serotherapy), 17 CD34+ selection with T-cell add-back grafts, and 65 unmanipulated grafts. RESULTS: The estimated 8-year survival of the entire cohort was 79%, transplant-related mortality was 21.7%, and the graft failure rate was 6.7%. Posttransplantation viral reactivation, grade II to IV acute graft-versus-host disease (aGvHD), and chronic graft-versus-host disease (cGvHD) complicated 49.6%, 35%, and 15% of transplantations, respectively. Use of TCRαß/CD19 depletion was associated with a significantly lower incidence of grade II to IV aGvHD (11.5%) and cGvHD (0%), although with a greater incidence of viral reactivation (70%) in comparison with other grafts. T-cell immune reconstitution was robust among CB transplants, although with a high incidence (56.7%) of grade II to IV aGvHD. Stable full donor engraftment was significantly greater at 80% among TCRαß+/CD19+-depleted and CB transplants versus 40% to 60% among the other groups. CONCLUSIONS: Rapidly accessible CB and haploidentical grafts are suitable alternatives for patients with no HLA-matched donor. Cord transplantation without serotherapy and TCRαß+/CD19+-depleted grafts produced comparable survival rates of around 80%, although with a high rate of aGvHD with the former and a high risk of viral reactivation with the latter that need to be addressed.

9.
J Allergy Clin Immunol ; 141(4): 1417-1426.e1, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28780238

RESUMO

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) is used as a therapeutic approach for primary immunodeficiencies (PIDs). The best outcomes have been achieved with HLA-matched donors, but when a matched donor is not available, a haploidentical or mismatched unrelated donor (mMUD) can be useful. Various strategies are used to mitigate the risk of graft-versus-host disease (GvHD) and rejection associated with such transplants. OBJECTIVE: We sought to evaluate the outcomes of haploidentical or mMUD HSCT after depleting GvHD-causing T-cell receptor (TCR) αß CD3+ cells from the graft. METHODS: CD3+TCRαß+/CD19+ depleted grafts were given in conditioned (except 3) children with PIDs. Treosulfan (busulfan in 1 patient), fludarabine, thiotepa, and anti-thymocyte globulin or alemtuzumab conditioning were used in 77% of cases, and all but 4 received GvHD prophylaxis. RESULTS: Twenty-five patients with 12 types of PIDs received 26 HSCTs. Three underwent transplantation for refractory GvHD that developed after the first cord transplantation. At a median follow-up of 20.8 months (range, 5 month-3.3 years), 21 of 25 patients survived and were cured of underlying immunodeficiency. Overall and event-free survival at 3 years were 83.9% and 80.4%, respectively. Cumulative incidence of grade II to IV acute GvHD was 22% ± 8.7%. No case of visceral or chronic GvHD was seen. Cumulative incidences of graft failure, cytomegalovirus, and/or adenoviral infections and transplant-related mortality at 1 year were 4.2% ± 4.1%, 58.8% ± 9.8%, and 16.1% ± 7.4%, respectively. Patients undergoing transplantation with systemic viral infections had poor survival in comparison with those with absent or resolved infections (33.3% vs 100%). CONCLUSION: CD3+TCRαß+ and CD19+ cell-depleted haploidentical or mMUD HSCT is a practical and viable alternative for children with a range of PIDs.

10.
Biol Blood Marrow Transplant ; 24(3): 529-536, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29155317

RESUMO

We previously published results for 70 children who received conditioning with treosulfan and cyclophosphamide (n = 30) or fludarabine (n = 40) before undergoing hematopoietic stem cell transplantation (HSCT) for primary immunodeficiency (PID). Toxicity was lower and T cell chimerism was better in the patients receiving fludarabine, but cohort numbers were relatively small and follow-up was short. Here we report outcomes of 160 children who received homogeneous conditioning with treosulfan, fludarabine, and, in most cases, alemtuzumab (n = 124). The median age at transplantation was 1.36 years (range, .09 to 18.25 years). Donors included 73 matched unrelated, 54 1 to 3 antigen-mismatched unrelated, 12 matched sibling, 17 other matched family, and 4 haploidentical donors. Stem cell source was peripheral blood stem cells (PBSCs) in 70, bone marrow in 49, and cord blood in 41. Median duration of follow-up was 4.3 years (range, .8 to 9.4 years). Overall survival was 83%. No patients had veno-occlusive disease. Seventy-four patients (46%) had acute GVHD, but only 14 (9%) greater than grade II. Four patients underwent successful retransplantation for graft loss or poor immune reconstitution. Another patient experienced graft rejection and died. There was no association between T cell chimerism >95% and stem cell source, but a significant association was seen between myeloid chimerism >95% and use of PBSCs without an increased risk of significant GVHD compared with other sources. All 11 patients with severe combined immunodeficiency diagnosed at birth were alive at up to 8.7 years of follow-up. Long-term studies are needed to determine late gonadotoxic effects, and pharmacokinetic studies are needed to identify whether specific targeting is advantageous. The combination of treosulfan, fludarabine, and alemtuzumab is associated with excellent results in HSCT for PID.

11.
Sci Immunol ; 1(6)2016 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-28783691

RESUMO

Recombination-activating genes 1 and 2 (RAG1 and RAG2) play a critical role in T and B cell development by initiating the recombination process that controls the expression of T cell receptor (TCR) and immunoglobulin genes. Mutations in the RAG1 and RAG2 genes in humans cause a broad spectrum of phenotypes, including severe combined immunodeficiency (SCID) with lack of T and B cells, Omenn syndrome, leaky SCID, and combined immunodeficiency with granulomas or autoimmunity (CID-G/AI). Using next-generation sequencing, we analyzed the TCR and B cell receptor (BCR) repertoire in 12 patients with RAG mutations presenting with Omenn syndrome (n = 5), leaky SCID (n = 3), or CID-G/AI (n = 4). Restriction of repertoire diversity skewed usage of variable (V), diversity (D), and joining (J) segment genes, and abnormalities of CDR3 length distribution were progressively more prominent in patients with a more severe phenotype. Skewed usage of V, D, and J segment genes was present also within unique sequences, indicating a primary restriction of repertoire. Patients with Omenn syndrome had a high proportion of class-switched immunoglobulin heavy chain transcripts and increased somatic hypermutation rate, suggesting in vivo activation of these B cells. These data provide a framework to better understand the phenotypic heterogeneity of RAG deficiency.

12.
J Allergy Clin Immunol ; 133(4): 1134-41, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24679470

RESUMO

BACKGROUND: Severe combined immunodeficiency (SCID) is a syndrome characterized by profound T-cell deficiency. BCG vaccine is contraindicated in patients with SCID. Because most countries encourage BCG vaccination at birth, a high percentage of patients with SCID are vaccinated before their immune defect is detected. OBJECTIVES: We sought to describe the complications and risks associated with BCG vaccination in patients with SCID. METHODS: An extensive standardized questionnaire evaluating complications, therapeutics, and outcomes regarding BCG vaccination in patients given a diagnosis of SCID was widely distributed. Summary statistics and association analysis was performed. RESULTS: Data on 349 BCG-vaccinated patients with SCID from 28 centers in 17 countries were analyzed. Fifty-one percent of the patients had BCG-associated complications, 34% disseminated and 17% localized (a 33,000- and 400-fold increase, respectively, over the general population). Patients receiving early vaccination (≤1 month) showed an increased prevalence of complications (P = .006) and death caused by BCG-associated complications (P < .0001). The odds of experiencing complications among patients with T-cell numbers of 250/µL or less at diagnosis was 2.1 times higher (95% CI, 1.4-3.4 times higher; P = .001) than among those with T-cell numbers of greater than 250/µL. BCG-associated complications were reported in 2 of 78 patients who received antimycobacterial therapy while asymptomatic, and no deaths caused by BCG-associated complications occurred in this group. In contrast, 46 BCG-associated deaths were reported among 160 patients treated with antimycobacterial therapy for a symptomatic BCG infection (P < .0001). CONCLUSIONS: BCG vaccine has a very high rate of complications in patients with SCID, which increase morbidity and mortality rates. Until safer and more efficient antituberculosis vaccines become available, delay in BCG vaccination should be considered to protect highly vulnerable populations from preventable complications.


Assuntos
Vacina BCG/efeitos adversos , Imunodeficiência Combinada Severa/epidemiologia , Vacina BCG/imunologia , Pré-Escolar , Comorbidade , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Prevalência , Estudos Retrospectivos , Risco , Imunodeficiência Combinada Severa/diagnóstico , Imunodeficiência Combinada Severa/terapia , Vacinação/efeitos adversos , Vacinação/legislação & jurisprudência
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