Pubertal development of transfusion-dependent thalassemia patients in the era of oral chelation with deferasirox: results from the French registry.

Not available.

New Perspectives on Primary Prophylaxis of Invasive Fungal Infection in Children Undergoing Hematopoietic Stem Cell Transplantation: A 10-Year Retrospective Cohort Study.

BACKGROUND: Allogenic hematopoietic stem cell transplantation (a-HCT) remains a therapeutic treatment for many pediatric hematological diseases. The occurrence of invasive fungal infections (IFIs) is a complication for which ECIL-8 recommends primary antifungal prophylaxis. In this study, we evaluated the impact of our local strategy of not systematically administering primary antifungal prophylaxis in children undergoing a-HCT on the occurrence and mortality of IFIs. METHODS: We performed a retrospective monocentric study from 2010 to 2020. We retained all proven and probable IFIs diagnosed during the first year post a-HCT. RESULTS: 308 patients were included. Eighteen patients developed twenty IFIs (thirteen proven, seven probable) (6.5%) among which aspergillosis (n = 10, 50%) and candidosis (n = 7, 35%) were the most frequently diagnosed infections. Only 2% of children died because of an IFI, which represents 14% of all deaths. Multivariate analysis found that age > 10 years (OR: 0.29), the use of a therapeutic antiviral treatment (OR: 2.71) and a low neutrophil count reconstitution (OR: 0.93) were significantly associated with the risk of IFI occurrence. There was also a trend of malignant underlying disease and status ≥ CR2 but it was not retained in multivariate analysis. CONCLUSIONS: IFI occurrence was not higher in our cohort than what is reported in the literature with the use of systematic antifungal prophylaxis, with a good survival rate nonetheless. Thus, a prophylaxis could be considered for children with a high risk of IFI such as those aged over 10 years.

Graft-versus-host disease and relapse/rejection-free survival after allogeneic transplantation for idiopathic severe aplastic anemia: a comprehensive analysis from the SAAWP of the EBMT.

Survival after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for severe idiopathic aplastic anemia (SAA) has improved in recent years, approaching 75% at 5 years. However, an SAA-adapted composite endpoint, graft-versus-host disease (GvHD) and relapse/rejection-free survival (GRFS), may more accurately assess patient outcomes beyond survival. We analyzed GRFS to identify risk factors and specific causes of GRFS failure. Our retrospective analysis from the Severe Aplastic Anemia Working Party of the European Society for Blood and Marrow Transplantation included 479 patients with idiopathic SAA who underwent allo-HSCT in two conventional situations: i) upfront allo-HSCT from a matched related donor (MRD) (upfront cohort), and ii) allo-HSCT for relapsed or refractory SAA (rel/ref cohort). Relevant events for GRFS calculation included graft failure, grade 3-4 acute GvHD, extensive chronic GvHD, and death. In the upfront cohort (n=209), 5-year GRFS was 77%. Late allo-HSCT (i.e., >6 months after SAA diagnosis) was the main poor prognostic factor, specifically increasing the risk of death as the cause of GRFS failure (hazard ratio [HR]=4.08; 95% confidence interval [CI]: 1.41-11.83; P=0.010). In the rel/ref cohort (n=270), 5-year GRFS was 61%. Age was the main factor significantly increasing the risk of death (HR=1.04; 95% CI: 1.02-1.06; P<0.001), acute GvHD (HR=1.03; 95% CI: 1.00-1.07; P=0.041), and chronic GvHD (HR=1.04; 95% CI: 1.01-1.08; P=0.032) as the cause of GRFS failure. GRFS after upfront MRD allo-HSCT was very good, notably with early allo-HSCT, confirming that younger patients with an MRD should be transplanted immediately. GRFS was worse in cases of salvage allo-HSCT, most notably in older patients, questioning the utility of allo-HSCT earlier in the disease course.

Alarming Upward Trend in Multidrug-Resistant Bacteria in a Large Cohort of Immunocompromised Children: A Four-Year Comparative Study.

Documenting bacteremia at the onset of fever in immunosuppressed children is challenging; therefore, it leads to the early administration of broad-spectrum antibiotics. We aimed to analyse the evolution of antibiotic resistance profiles of bacterial bloodstream infections (BSI) and gut colonisations in a large cohort of immunocompromised children carrying a central venous catheter, in comparison with a prior, similar study conducted in our centre from 2014 to 2017. A retrospective, observational cohort study was conducted from January 2018 to December 2021, in a tertiary centre for paediatric immuno-haematology and oncology. Empirical antibiotic therapy was adapted to the immunosuppression risk group and prior bacterial colonisation. There was a mean of 6.9 BSI/1000 patient bed days. Multidrug-resistant bacteria (MDRB) associated BSI accounted for 35/273 (12.8%). The incidence of MDRB gum/gut colonisation and MDRB associated BSI increased annually and correlated with the level of immunosuppression (p = 0.024). One third (34.7%) of the BSI episodes were not associated with neutropenia. As compared to the previous study, an alarming emergence of MDRB responsible for gut colonisations and BSI in immunosuppressed children was reported over the last four years. The degree of immunosuppression directly correlates with the risk of having an MDRB gut colonisation or MDRB BSI.

Real-world use of defibrotide for veno-occlusive disease/sinusoidal obstruction syndrome: the DEFIFrance Registry Study.

Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of haematopoietic cell transplantation (HCT) conditioning. The DEFIFrance post-marketing registry study evaluated effectiveness and safety in patients who received defibrotide. It collected retrospective/prospective patient data from 53 French HCT centres from July 2014 to March 2020. Primary endpoints were survival and complete response (CR; total serum bilirubin <2 mg/dL, multiorgan failure resolution) at Day 100 post-HCT among patients with severe/very severe VOD/SOS. A secondary endpoint was evaluation of treatment-emergent serious adverse events (TESAEs) of interest. Of 798 patients analysed, 251 and 81 received defibrotide treatment for severe/very severe VOD/SOS and mild/moderate VOD/SOS post-HCT, respectively; 381 received defibrotide for VOD/SOS prophylaxis. In patients with severe/very severe VOD/SOS post-HCT, Kaplan-Meier-estimated CR at Day 100 was 74% (95% confidence interval [CI]: 66%, 81%). At Day 100, 137/251 (55%) were alive and in CR. Kaplan-Meier-estimated Day 100 post-HCT survival was 61% (95% CI: 55%, 67%) in patients with severe/very severe VOD/SOS. TESAEs of interest occurred in 29% of these patients; VOD/SOS-related mortality at 12 months was 15%. DEFIFrance represents the largest collection of real-world data on post-registration defibrotide use, supporting the real-world utility of defibrotide for patients with severe/very severe VOD/SOS post-HCT.

Interest of the preventive and curative use of defibrotide on the occurrence and severity of sinusoidal obstruction syndrome after hematopoietic stem cell transplant in children.

Defibrotide (DF) is indicated for the treatment of severe sinusoidal obstruction syndrome (SOS) following hematopoietic stem cell transplantation (HSCT), but its prophylactic use against SOS is not recommended yet. This study describes the impact of the preventive and curative use of DF on reducing the incidence and severity of SOS in children. Patients aged 0-19 years, who received allogenic HSCT after myeloablative conditioning regimen with busulfan or total body irradiation in our comprehensive cancer center, between 2013 and 2017, were included. The Baltimore or modified Seattle criteria were used for SOS diagnosis. SOS was graded using the 2017 European Society for Blood and Marrow Transplantation classification defining severity criteria of SOS in children. SOS occurrence tended to decrease with prophylactic DF, but no significant difference was observed in terms of severity. When not treated with preventive DF, 50% (19/38) of the patients with SOS were graded severe to very severe, but only 37% (7/19) had organ dysfunction. Curative DF was administered at a median of 2 days post-HSCT, for a median of 6.5 days. The absence of fatal SOS supports the use of early curative DF with acceptable toxicities and questions the optimal duration of DF treatment.

Teenagers and young adults with a past of allogenic hematopoietic stem cell transplantation are at significant risk of chronic kidney disease.

BACKGROUND: Allogenic hematopoietic stem cell transplantation (aHSCT) remains the treatment of choice for some malignant hemopathies in children, albeit with the risk of long-term consequences, including chronic kidney disease (CKD). METHODS: In our single tertiary referral center, we retrospectively assessed the long-term renal outcome in a cohort of children and adolescents who had undergone aHSCT for malignant hemopathies between 2003 and 2017. We distinguished glomerular and tubular dysfunctions and assessed the accuracy of the most common formula(s) to estimate glomerular filtration rate (GFR) during standard clinical follow-up. RESULTS: Among the 166 patients who had received aHSCT, 61 underwent kidney functional assessment 1 to 10 years post-transplantation. Twenty-seven patients (44.3%) had a CKD with glomerular impairment, including 20 patients with a GFR < 90 mL/min/1.73 m2, and among these, 5 patients < 60 mL/min/1.73 m2. Patients with tubular signs had a significantly higher baseline GFR: 112 mL/min/1.73 m2 [100; 120] versus 102 [99.0; 112.5] for patients without kidney involvement, and 76 [61; 86] for patients with CKD (p < 0.01). Schwartz, CKiDU25, and EKFC formulas significantly overestimated mGFR, with a P30% ≤ 30%, which could lead to overlooking CKD diagnosis in this population. No patient reached kidney failure. CONCLUSIONS: In conclusion, our study shows that CKD represents an important long-term sequela for children and adolescents who undergo aHSCT for malignant hemopathies, either with glomerular dysfunction or with the more insidious tubular dysfunction which could potentially impact growth. These patients could benefit from specialized long-term nephrology follow-up. A higher resolution version of the Graphical abstract is available as Supplementary information.

Improved outcome in children compared to adolescents and young adults after allogeneic hematopoietic stem cell transplant for acute myeloid leukemia: a retrospective study from the Francophone Society of Bone Marrow Transplantation and Cell Therapy (SFGM-TC).

BACKGROUND: There are currently few data on the outcome of acute myeloid leukemia (AML) in adolescents after allogeneic HSCT. The aim of this study is to describe the outcome and its specific risk factors for children, adolescents and young adults after a first allogeneic HSCT for AML. METHODS: In this retrospective study, we compared the outcome of AML patients receiving a first allogeneic HSCT between 2005 and 2017 according to their age at transplantation's time: children (< 15 years, n = 564), adolescent and post-adolescent (APA) patients (15-25 years, n = 647) and young adults (26-40 years; n = 1434). RESULTS: With a median follow-up of 4.37 years (min-max 0.18-14.73 years), the probability of 2-year overall survival (OS) was 71.4% in children, 61.1% in APA patients and 62.9% in young adults (p = 0.0009 for intergroup difference). Both relapse and non-relapse mortality (NRM) Cumulative Incidence (CI) estimated at 2 years were different between the age groups (30.8% for children, 35.2% for APA patients and 29.4% for young adults-p = 0.0254, and 7.0% for children, 10.6% for APA patients and 14.2% for young adults, p < 0.0001; respectively). Whilst there was no difference between the three groups for grade I to IV acute GVHD CI at 3 months, the chronic GVHD CI at 2 years was higher in APA patients and young adults (31.4% and 36.4%, respectively) in comparison to the children (17.5%) (p < 0.0001). In multivariable analysis, factors associated with death were AML cytogenetics (HR1.73 [1.29-2.32] for intermediate risk 1, HR 1.50 [1.13-2.01] for intermediate risk 2, HR 2.22 [1.70-2.89] for high cytogenetics risk compared to low risk), use of TBI ≥ 8 Grays (HR 1.33 [1.09-1.61]), disease status at transplant (HR 1.40 [1.10-1.78] for second Complete Remission (CR), HR 2.26 [1.02-4.98] for third CR and HR 3.07 [2.44-3.85] for active disease, compared to first CR), graft source (HR 1.26 [1.05-1.50] for Peripheral Blood Stem Cells compared to Bone Marrow) and donor age (HR 1.01 (1-1.02] by increase of 1 year). CONCLUSION: Age is an independent risk factor for NRM and extensive chronic GVHD. This study suggests that APA patients with AML could be beneficially treated with a chemotherapy-based MAC regimen and bone marrow as a stem cells source.

Recurrent bacterial infections, but not fungal infections, characterise patients with ELANE-related neutropenia: a French Severe Chronic Neutropenia Registry study.

Among 143 patients with elastase, neutrophil-expressed (ELANE)-related neutropenia enrolled in the French Severe Chronic Neutropenia Registry, 94 were classified as having severe chronic neutropenia (SCN) and 49 with cyclic neutropenia (CyN). Their infectious episodes were classified as severe, mild or oral, and analysed according to their natural occurrence without granulocyte-colony stimulating factor (G-CSF), on G-CSF, after myelodysplasia/acute leukaemia or after haematopoietic stem-cell transplantation. During the disease's natural history period (without G-CSF; 1913 person-years), 302, 957 and 754 severe, mild and oral infectious events, respectively, occurred. Among severe infections, cellulitis (48%) and pneumonia (38%) were the most common. Only 38% of episodes were microbiologically documented. The most frequent pathogens were Staphylococcus aureus (37·4%), Escherichia coli (20%) and Pseudomonas aeruginosa (16%), while fungal infections accounted for 1%. Profound neutropenia (<200/mm3 ), high lymphocyte count (>3000/mm3 ) and neutropenia subtype were associated with high risk of infection. Only the p.Gly214Arg variant (5% of the patients) was associated with infections but not the overall genotype. The first year of life was associated with the highest infection risk throughout life. G-CSF therapy achieved lower ratios of serious or oral infectious event numbers per period but was less protective for patients requiring >10 µg/kg/day. Infections had permanent consequences in 33% of patients, most frequently edentulism.

A multicentre, multinational, prospective, observational registry study of defibrotide in patients diagnosed with veno-occlusive disease/sinusoidal obstruction syndrome after haematopoietic cell transplantation: an EBMT study.

Severe hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of haematopoietic cell transplantation (HCT). This multinational, prospective, observational study (NCT03032016), performed by the EBMT, enrolled patients treated with defibrotide from April 2015 to July 2018. This analysis focused on defibrotide-treated patients with VOD/SOS post-HCT. The primary endpoint was incidence of serious adverse events (SAEs) of interest up to 12 months post-HCT in patients with severe VOD/SOS. Overall, 104 defibrotide-treated patients with VOD/SOS post-HCT were enrolled: 62 had severe VOD/SOS and comprised the primary study population, including 36 with multi-organ dysfunction/failure (MOD/MOF). SAEs of interest occurred in 20 of 62 (32%) severe VOD/SOS patients; the most common by category were infection (24%) and bleeding (13%). In patients with severe VOD/SOS, the Kaplan-Meier-estimated Day 100 survival rate was 73% (95% CI: 60%, 82%) with VOD/SOS resolution by Day 100 in 45 of 62 (73%) patients. MOD/MOF resolved in 19 of 36 (53%) patients with MOD/MOF at VOD/SOS diagnosis. Results from this multicentre registry study build on prior defibrotide studies supporting the utility of defibrotide for the treatment of VOD/SOS post-HCT. These results provide additional real-world evidence of the effectiveness and safety of defibrotide in patients with VOD/SOS post-HCT.

Effects of Genotypes and Treatment on Oxygenscan Parameters in Sickle Cell Disease.

(1) Background: The aim of the present study was to compare oxygen gradient ektacytometry parameters between sickle cell patients of different genotypes (SS, SC, and S/ß+) or under different treatments (hydroxyurea or chronic red blood cell exchange). (2) Methods: Oxygen gradient ektacytometry was performed in 167 adults and children at steady state. In addition, five SS patients had oxygenscan measurements at steady state and during an acute complication requiring hospitalization. (3) Results: Red blood cell (RBC) deformability upon deoxygenation (EImin) and in normoxia (EImax) was increased, and the susceptibility of RBC to sickle upon deoxygenation was decreased in SC patients when compared to untreated SS patients older than 5 years old. SS patients under chronic red blood cell exchange had higher EImin and EImax and lower susceptibility of RBC to sickle upon deoxygenation compared to untreated SS patients, SS patients younger than 5 years old, and hydroxyurea-treated SS and SC patients. The susceptibility of RBC to sickle upon deoxygenation was increased in the five SS patients during acute complication compared to steady state, although the difference between steady state and acute complication was variable from one patient to another. (4) Conclusions: The present study demonstrates that oxygen gradient ektacytometry parameters are affected by sickle cell disease (SCD) genotype and treatment.

Haplo-identical or mismatched unrelated donor hematopoietic cell transplantation for Fanconi anemia: Results from the Severe Aplastic Anemia Working Party of the EBMT.

Allogeneic hematopoietic cell transplantation (HCT) is the only curative option for bone marrow failure or hematopoietic malignant diseases for Fanconi anemia (FA) patients. Although results have improved over the last decades, reaching more than 90% survival when a human leukocyte antigen (HLA)-identical donor is available, alternative HCT donors are still less reported. We compared HCT outcomes using HLA-mismatched unrelated donors (MMUD; n = 123) or haplo-identical donors (HDs), either using only in vivo T cell depletion (n = 33) or T cells depleted in vivo with some type of graft manipulation ex vivo (n = 59) performed for FA between 2000 and 2018. Overall survival (OS) by 24 months was 62% (53-71%) for MMUD, versus 80% (66-95%) for HDs with only in vivo T cell depletion and 60% (47-73%) for HDs with in vivo and ex vivo T cell depletion (p = .22). Event-free survival (EFS) was better for HD-transplanted FA patients with only in vivo T cell depletion 86% (73-99%) than for those transplanted from a MMUD 58% (48-68%) or those with graft manipulation 56% (42-69%) (p = .046). Grade II-IV acute graft-versus-host disease (GVHD) was 41% (MMUD) versus 40% (HDs with no graft manipulation) versus 17% (HDs with T cell depleted graft), (p = .005). No differences were found for the other transplant related outcomes. These data suggest that HDs might be considered as an alternative option for FA patients with better EFS using unmanipulated grafts.

Ruxolitinib in children with steroid-refractory acute graft-versus-host disease: A retrospective multicenter study of the pediatric group of SFGM-TC.

BACKGROUND: We conducted a national multicenter retrospective study in France to evaluate the efficacy and tolerance of ruxolitinib in children with steroid-refractory acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplant. PROCEDURE: Patients were recruited from the 15 pediatric transplantation centers. Transplanted patients were eligible if they met the following criteria: aged ≤ 18 years at transplantation, receiving a myeloablative allogeneic hematopoietic stem cell transplant, having an aGVHD of grade ≥2, and treated with ruxolitinib for steroid-refractory aGVHD. RESULTS: Twenty-nine patients received ruxolitinib for steroid-refractory aGVHD. Six patients achieved a complete response at day 28 after the start of treatment but finally 19 patients (65.5%) achieved a complete response (CR) with a median delay of 41 days (5-93 days). Two patients had a partial response. All patients who achieved CR or partial response discontinued corticosteroid treatment. Eight patients showed treatment failure. The overall response rate was 72.4%. Twenty-three of 29 patients were alive at a median follow-up of 685 days (177-1042 days) after the hematopoietic stem cell transplantation. Viral replication was observed in 41.4% of cases. We did not observe severe hematological adverse events and cytopenia requiring a modification of ruxolitinib doses always resolved. The median initial dose of ruxolitinib was 12.6 mg/m2 /day with an important range. We could not demonstrate any relationship between initial dose and effectiveness. CONCLUSION: Ruxolitinib may constitute a promising second-line treatment for children with steroid-refractory aGVHD that should be validated in a prospective large-scale pharmacokinetic and efficacy trial.

Association of fludarabin, cytarabine, and fractioned gemtuzumab followed by hematopoietic stem cell transplantation for first-line refractory acute myeloid leukemia in children: A single-center experience.

CONTEXT: Acute myeloid leukemia (AML) is a rare disease in children, with only 50% to 60% event-free survival. Among patients with AML, 10% do not respond to first-line chemotherapy. There is no recommendation concerning second-line treatments. Gemtuzumab ozogamicin (GO) is a monoclonal antibody targeting CD33, linked to calicheamicin. We report the efficacy and tolerance of a salvage regimen of fludarabin, cytarabine, and GO (FLA-GO) in patients refractory to first-line treatment. METHODS: Eight patients (median age 14.5 years), who had more than 2% minimal residual disease (MRD) by flow cytometry (MRD flow), received gemtuzumab 3 mg/m² on days 1, 4, 7, associated with cytarabine 2000 mg/m² and fludarabin 30 mg/m² on days 1 to 5. RESULTS: Six patients achieved complete remission (CR) (blast count morphology ≤5 × 10-2 , CR-MRD flow <1 × 10-3 for four patients). Five patients received a second course. We observed 11 episodes of febrile neutropenia, including 6 septicemias without complication. There was no fungal infection or toxic death. Two patients received granulocyte colony stimulating factor. One patient had partial platelet recovery; one, prolonged pancytopenia. All patients received hematopoietic stem cell transplantation (HSCT). We observed five mild-to-severe sinusoidal obstruction syndromes during HSCT procedures, particularly in patients who did not receive defibrotide prophylaxis. At the date of last contact (median follow-up: 58 months; range: 22-78), six patients were in continuous CR with negative MRD. Two patients died of post-HSCT relapse. CONCLUSION: FLA-GO is a good salvage regimen for pediatric refractory AML, with significant but acceptable toxicity. HSCT is mandatory to achieve sustained CR in these patients.

Goal-Oriented Monitoring of Cyclosporine Is Effective for Graft-versus-Host Disease Prevention after Hematopoietic Stem Cell Transplantation in Sickle Cell Disease and Thalassemia Major.

Graft-versus-host disease (GVHD) is an important challenge and a major cause of morbidity and mortality in children after hematopoietic stem cell transplant (HSCT). Herein we report our institution's experience of goal-oriented Bayesian monitoring for cyclosporine (CsA) used alone as GVHD prophylaxis during the post-transplant period in pediatric patients with thalassemia major (TM) or sickle cell anemia (SCA) undergoing HLA-matched HSCT. We also studied evolution of chimerism. Twenty-six consecutive patients (SCA, 14; TM, 12) underwent matched sibling donor (MSD) HSCT from 2004 to 2014. All patients received a myeloablative conditioning regimen. GVHD prophylaxis consisted of 20 mg/kg antithymocyte globulin in the conditioning regimens and then CsA alone in the post-transplant period. Target CsA trough blood concentration (TBC) was 150 ± 20 ng/mL. At last follow-up, all patients were alive and free of disease, even in cases of mixed chimerism. Engraftment occurred in all patients. No patient developed grades II to IV acute GVHD, 4 patients developed acute grade I skin GVHD, and only 1 presented with chronic pulmonary GVHD. A better control of GVHD and immunosuppression by a strict monitoring of CsA TBC as described herein is promising and could play a crucial role. Further investigations are required, but this study opens new perspectives to improve survival and safety of HSCT from alternative donors in TM and SCA to levels compatible with that obtained with MSDs.

Medication adherence after pediatric allogeneic stem cell transplantation: Barriers and facilitators.

PURPOSE: Immunosuppressive therapy following pediatric hematopoietic stem cell transplantation is essential for the patient's prognosis, as the antibioprophylaxis and the isolation measures. But medication adherence is suboptimal for children and adolescents, from 52 to 73% in literature. The aim of this study is to provide an understanding of medication adherence after pediatric allogeneic stem cell transplantation (SCT), by identifying facilitators and barriers. METHOD: Semi-structured interviews were conducted by a pharmacist with caregivers and healthcare providers in a pediatric centre. Four topics were discussed: transplantation, post-transplantation therapies, caregivers' experience and the healthcare system. Interviews were audiotaped, transcribed and analysed by inductive approach. FINDINGS: Semi-structured interviews with 15 caregivers and 21 healthcare providers identified factors of medication adherence and hygiene measures. The long-term nature of therapy and difficult transitions of care were identified as major barriers. Recognizing the benefits of medication and parental involvement are facilitators. Furthermore, caregivers expressed the need to take into consideration the family entity. They would like also to receive earlier information from healthcare providers before hospital discharge. Those needs were not always identified by healthcare providers. CONCLUSION: This analysis revealed barriers and facilitators to the medication adherence and to the care. It demonstrated similarities and differences between caregivers and healthcare providers' perceptions and has thereby initiated an improvement process of the healthcare system. As part of this process, medical and paramedical healthcare providers at this French pediatric centre are currently working on a support program for post-alloSCT hospital-home transition.

Single-Unit versus Double-Unit Umbilical Cord Blood Transplantation in Children and Young Adults with Residual Leukemic Disease.

We previously reported in a French prospective randomized study that transplantation of 2 unrelated cord blood (UCB) units instead of 1 unit does not decrease the risk of transplantation failure but may enhance alloreactivity. Here we evaluated the influence of pretransplantation minimal residual disease (MRD) on leukemia relapse and survival after single- versus double-UCB transplantation (UCBT). Among 137 children and young adults who underwent UCBT in this randomized study, 115 had available data on MRD assessment done immediately before initiation of the pretransplantation conditioning regimen. MRD was considered positive at a level of ≥10-4, which was the case of 43 out of 115 patients. Overall, the mean 3-year survival probability was 69.1 ± 4.4%, and it was not significantly influenced by the MRD level: 70.7 ± 5.4% in MRD-negative (<10-4) patients (n = 72), 71.1 ± 9.4% in MRD-positive patients with 10-4 ≤ MRD <10-3 (n = 26) and 58.8 ± 11.9% in MRD-positive patients with ≥10-3 (n = 17). In the MRD-positive group, the mean risk of relapse was significantly lower in the double-UCBT arm compared with the single-UCBT arm (10.5 ± 7.2% versus 41.7 ± 10.4%; P = .025) leading to a higher mean 3-year survival rate (82.6 ± 9.3% versus 53.6 ± 10.3%; P = .031). This difference was observed only in patients who had not received antithymocyte globulin during their conditioning regimen. In the MRD-negative group, there was no differencebetween the single- and the double-UCBT arms. We conclude that even in cases of positive pretransplantation MRD, UCBT in children and young adults with acute leukemia yields a high cure rate, and that a double-unit strategy may enhance the graft-versus-leukemia effect and survival in these patients.

Clinical management and viral genomic diversity analysis of a child's influenza A(H1N1)pdm09 infection in the context of a severe combined immunodeficiency.

INTRODUCTION: A child with severe combined immunodeficiency (SCID) had an influenza A(H1N1)pdm09 infection with viral excretion longer than 6 months, during 2013-2014 influenza season, despite cord blood transplantation and antiviral treatments. METHODS: Conventional real-time RT-PCR methods were used to estimate viral load and to detect the presence of the common N1 neuraminidase (NA) H275Y substitution responsible for oseltamivir resistance. Next-generation sequencing (NGS) of influenza viruses was performed retrospectively to characterize viral quasispecies in specimens. RESULTS: The patient was first treated with oral oseltamivir, leading to detection of low-levels of NA-H275Y substitution. Concomitant cord blood cell transplantation, intravenous administration of zanamivir and immunoglobulins led to an increase in white blood cells and influenza viral load decrease. A viral rebound occurred as soon as the antiviral treatment was discontinued. Eventually, influenza viral load was negated with immune reconstitution. NGS found influenza quasispecies harboring NA-E119A substitution (10.3%). Moreover, NGS showed that viral genomic diversity evolved under antiviral treatment and immune status. CONCLUSIONS: Conventional virological techniques were sufficient for influenza infection follow-up but NGS performances allowed characterization of viral variants evolution in this specific case of prolonged influenza virus infection. New and efficient treatments against influenza in immunocompromised patients are needed.

Increased Risk of Thrombosis Associated with Peripherally Inserted Central Catheters Compared with Conventional Central Venous Catheters in Children with Leukemia.

OBJECTIVE: To study the risk of catheter-associated thrombosis (CAT) between peripherally inserted central catheters (PICCs) and tunneled central venous catheters in children with leukemia. STUDY DESIGN: We analyzed all PICCs and conventional tunneled catheters placed in patients aged <18 years and admitted to our institute for leukemia treatment between February 2008 and April 2014. Cases of symptomatic CAT were confirmed by ultrasound and treated with low-molecular-weight heparin. RESULTS: During the study period, 157 PICCs and 138 conventional tunneled catheters were placed in 192 patients with leukemia. CAT incidence was 1.5% (n = 2) in the conventional tunneled catheter group and 10.2% (n = 16) in the PICC group. The OR for CAT occurrence after PICC vs conventional tunneled catheter placement was 5.6 (95% CI, 1.2-26.5). CONCLUSION: Our results suggest that the use of PICCs in children with leukemia increases the risk of CAT in comparison with the use of conventional tunneled catheters. Further randomized controlled studies are needed to characterize this risk and to better define indications.