Key Points• Children with AL given haplo-HSCT after ab T-and B-cell depletion are exposed to a low risk of acute and chronic GVHD and NRM.• The leukemia-free, GVHDfree survival of patients given this type of allograft is comparable to that of HLAmatched donor HSCT recipients.Allogeneic hematopoietic stem cell transplantation (HSCT) from an HLA-haploidentical relative (haplo-HSCT) is a suitable option for children with acute leukemia (AL) either relapsed or at high-risk of treatment failure. We developed a novel method of graft manipulation based on negative depletion of ab T and B cells and conducted a prospective trial evaluating the outcome of children with AL transplanted with this approach. Eighty AL children, transplanted between September 2011 and September 2014, were enrolled in the trial. All children were given a fully myeloablative preparative regimen. Anti-T-lymphocyte globulin from day 25 to 23 was used for preventing graft rejection and graft-versus-host disease (GVHD); no patient received any posttransplantation GVHD prophylaxis. Two children experienced primary graft failure. The cumulative incidence of skin-only, grade 1-2 acute GVHD was 30%; no patient developed extensive chronic GVHD. Four patients died, the cumulative incidence of nonrelapse mortality being 5%, whereas 19 relapsed, resulting in a 24% cumulative incidence of relapse. With a median follow-up of 46 months for surviving patients, the 5-year probability of chronic GVHD-free, relapsefree survival (GRFS) is 71%. Total body irradiation-containing preparative regimen was the only variable favorably influencing relapse incidence and GRFS. The outcomes of these 80 patients are comparable to those of 41 and 51 children given transplantation from an HLA-identical sibling or a 10/10 allelic-matched unrelated donor in the same period. These data indicate that haplo-HSCT after ab T-and B-cell depletion represents a competitive alternative for children with AL in need of urgent allograft. This trial was registered at www.clinicaltrials.gov as #NCT01810120. (Blood. 2017;130(5):677-685)

We report the outcome of 12 consecutive pediatric patients with Fanconi anemia (FA) who had neither an HLA-identical sibling nor an HLA-matched unrelated donor and who were given T cell-depleted, CD34(+) positively selected cells from a haploidentical related donor after a reduced-intensity, fludarabine-based conditioning regimen. Engraftment was achieved in 9 of 12 patients (75%), and the cumulative incidence of graft rejection was 17% (95% confidence interval [CI], 5% to 59%). Cumulative incidences of grades II to IV acute and chronic graft-versus-host disease were 17% (95% CI, 5% to 59%) and 35% (95% CI, 14% to 89%), respectively. The conditioning regimen was well tolerated, with no fatal regimen-related toxicity and 3 cases of grade III regimen-related toxicity. The cumulative incidence of transplant-related mortality was 17% (95% CI, 5% to 59%). The 5-year overall survival, event-free survival, and disease-free survival were 83% (95% CI, 62% to 100%), 67% (95% CI, 40% to 93%), and 83% (95% CI, 62% to 100%), respectively. These data demonstrate that a fludarabine-based conditioning regimen, followed by infusion of high doses of T cell-depleted stem cells, is able to ensure engraftment with good overall survival and disease-free survival, confirming the feasibility of haploidentical hematopoietic stem cell transplantation in FA. To the best of our knowledge, this is the largest series of hematopoietic stem cell transplantation from a haploidentical related donor in FA patients reported to date.

Our analysis of the viral origins of nosocomial infections in NICUs can be a valuable tool in the investigation of neonatal infections. The mortality rates reported in this analysis demonstrate the significance of noncongenital viral infections in NICUs and the need for more effective outbreak prevention strategies.

Achieving complete remission (CR) in childhood relapsed/refractory acute lymphoblastic leukaemia (ALL) is a difficult task. Bortezomib, a proteasome inhibitor, has in vitro activity against ALL blasts. A phase I-II trial, reported by the Therapeutic Advances in Childhood Leukaemia and Lymphoma (TACL) consortium, demonstrated that bortezomib with chemotherapy has acceptable toxicity and remarkable activity in patients with relapsed ALL failing 2-3 previous regimens. We evaluated bortezomib in combination with chemotherapy in 30 and 7 children with B-cell precursor (BCP) and T-cell ALL, respectively. Bortezomib (1·3 mg/m /dose) was administered intravenously on days 1, 4, 8, and 11. Chemotherapy agents were the same as those used in the TACL trial, consisting of dexamethasone, doxorubicin, vincristine and pegylated asparaginase. Three patients (8·1%) died due to infections. Twenty-seven patients (72·9%) achieved CR or CR with incomplete platelet recovery (CRp). Fourteen had minimal residual disease (MRD) lower than 0·1%. Twenty-two of 30 BCP-ALL patients (73·3%) and 5/7 patients (71%) with T-cell ALL achieved CR/CRp. The 2-year overall survival (OS) is 31·3%; CR/CRp patients with an MRD response had a remarkable 2-year OS of 68·4%. These data confirm that the combination of bortezomib with chemotherapy is a suitable/effective option for childhood relapsed/refractory ALL.

Acute myeloid leukemia (AML) is a heterogeneous group of diseases, whose classification is based on lineage-commitment and genetics. Although rare in childhood, it is the most common type of acute leukemia in adults, accounting for 80% of all cases in this age group. The prognosis of this disease remains poor (especially in childhood, as compared to acute lymphoblastic leukemia); however, overall survival has significantly improved over the past 30 years. The health of the oral cavity is a remarkable reflection of the systemic status of an individual. Identification of the signs and symptoms of oral lesions can act as a warning sign of hidden and serious systemic involvement. Moreover, they may be the presenting feature of acute leukemia and provide important diagnostic indicators. Primary oral alterations are identified in up to 90% of cases of acute myeloid leukemia and consist of petechiae, spontaneous bleeding, mucosal ulceration, gingival enlargement with or without necrosis, infections, hemorrhagic bullae on the tongue, and cracked lips. Poor oral hygiene is a well-known risk factor for local and systemic infectious complications. Oro-dental complications due to AML treatment can affect the teeth, oral mucosa, soft and bone tissue, and contribute to opportunistic infections, dental decay, and enamel discoloration. The treatment of acute myeloid leukemia is still associated with high mortality and morbidity. The management is multimodal, involving aggressive multidrug chemotherapy and, in most cases, allogenic bone marrow transplantation. Periodontal and dental treatment for patients with leukemia should always be planned and concerted with hematologists.

Pathophysiology of graft failure (GF) occurring after allogeneic hematopoietic stem cell transplantation (HSCT) still remains elusive. We measured serum levels of several different cytokines/chemokines in 15 children experiencing GF, comparing their values with those of 15 controls who had sustained donor cell engraftment. Already at day +3 after transplantation, patients developing GF had serum levels of interferon (IFN)-γ and CXCL9 (a chemokine specifically induced by IFNγ) significantly higher than those of controls (8859±7502 vs. 0 pg/mL, P=0.03, and 1514.0±773 vs. 233.6±50.1 pg/mlL, P=0.0006, respectively). The role played by IFNγ in HSCT-related GF was further supported by the observation that a rat anti-mouse IFNγ-neutralizing monoclonal antibody promotes donor cell engraftment in Ifngr1−/−mice receiving an allograft. In comparison to controls, analysis of bone marrow-infiltrating T lymphocytes in patients experiencing GF documented a predominance of effector memory CD8+ cells, which showed markers of activation (overexpression of CD95 and downregulation of CD127) and exhaustion (CD57, CD279, CD223 and CD366). Finally, we obtained successful donor engraftment in 2 out of 3 children with primary hemophagocytic lymphohistiocytosis who, after experiencing GF, were re-transplanted from the same HLA-haploidentical donor under the compassionate use coverage of emapalumab, an anti-IFNγ monoclonal antibody recently approved by the US Food and Drug Administration for treatment of patients with primary hemophagocytic lymphohistiocytosis. Altogether, these results suggest that the IFNγ pathway plays a major role in GF occurring after HSCT. Increased serum levels of IFNγ and CXCL9 represent potential biomarkers useful for early diagnosis of GF and provide the rationale for exploring the therapeutic/preventive role of targeted neutralization of IFNγ.

SummaryAlthough allogeneic haematopoietic stem cell transplantation (HSCT) still represents the only consolidated possibility of cure for sickle cell disease (SCD) patients, its use has been limited by the risk of morbidity and mortality associated with conventional myeloablative therapy. The introduction of treosulfan to replace busulfan in conditioning regimens has recently been explored by virtue of its lower toxicity profile. We report our experience with a treosulfan/thiotepa/fludarabine conditioning for human leucocyte antigen (HLA)-matched sibling or unrelated donor-HSCT in 15 children with SCD, and compare patient outcomes with those of a historical cohort (15 patients) given a busulfan-based regimen. Engraftment was achieved in 28 out of 30 patients (93%), with one case of graft failure in either group. The conditioning regimen was well tolerated in both groups, with no cases of grade III-IV regimen-related toxicity. The 7-year overall survival (OS) and disease-free survival (DFS) for the whole cohort were 100% and 93%, respectively, with a 93% DFS in both busulfan and treosulfan groups. No SCD-related adverse events occurred after engraftment in patients with complete or mixed donor chimerism. This retrospective analysis suggests that a treosulfan-based conditioning regimen is able to ensure engraftment with excellent OS/DFS and low regimen-related toxicity in patients with SCD.

Immune Thrombocytopenia (ITP) is an autoimmune disease characterized by autoantibodies-mediated platelet destruction, a prevalence of M1 pro-inflammatory macrophage phenotype and an elevated T helper 1 and T helper 2 lymphocytes (Th1/Th2) ratio, resulting in impairment of inflammatory profile and immune response. Macrophages are immune cells, present as pro-inflammatory classically activated macrophages (M1) or as anti-inflammatory alternatively activated macrophages (M2). They have a key role in ITP, acting both as effector cells, phagocytizing platelets, and, as antigen presenting cells, stimulating auto-antibodies against platelets production. Eltrombopag (ELT) is a thrombopoietin receptor agonist licensed for chronic ITP to stimulate platelet production. Moreover, it improves T and B regulatory cells functions, suppresses T-cells activity, and inhibits monocytes activation. We analyzed the effect of ELT on macrophage phenotype polarization, proposing a new possible mechanism of action. We suggest it as a mediator of macrophage phenotype switch from the M1 pro-inflammatory type to the M2 anti-inflammatory one in paediatric patients with ITP, in order to reduce inflammatory state and restore the immune system function. Our results provide new insights into the therapy and the management of ITP, suggesting ELT also as immune-modulating drug.