Impact of SARS-CoV-2 Pandemic and Lockdown on the HRSV Circulation: Experience of Three Spoke Hospitals in Northern Italy.

The SARS-CoV-2 Pandemic affected the global epidemiology of respiratory infections, including Human Respiratory Syncytial Virus (HRSV), thanks to state governments' implementation of mitigation strategies, like the promotion of face masks and lockdowns. However, after the Pandemic, the dramatic resurge of these diseases was reported worldwide. Our retrospective study, involving three Spoke Pediatric Departments, includes all the infants under one year of age hospitalized for HRSV bronchiolitis in a period before the Pandemic period (2017-2020), during the SARS-CoV-2 Pandemic (2020-2021), and after the Pandemic (2021-2023). The primary aim was to analyze the temporal trend of HRSV in these three periods. Then, the clinical and epidemiological characteristics were analyzed to highlight the clinical differences in the affected patients, in the severity of the infections, and in the short-term outcomes. Ultimately, we analyzed the HRSV prevalence in the global bronchiolitis hospitalization over the reported periods. Overall, we included 237 patients. Before the Pandemic, the peak was recorded in January and February, while after the Pandemic, the peak was in November and December. A higher prevalence of HRSV was demonstrated after the Pandemic compared to the period before the Pandemic; overall, no difference in severity was reported. In conclusion, an increase in HRSV cases after the Pandemic has been demonstrated with an anticipated peak, while no differences were recorded in severity.

Management of Acute Bronchiolitis in Spoke Hospitals in Northern Italy: Analysis and Outcome.

Bronchiolitis is an acute viral infection of the lower respiratory tract that affects infants and young children. Respiratory syncytial virus (RSV) is the most common causative agent; however, other viruses can be involved in this disease. We retrospectively reviewed the clinical features of infants aged less than 12 months hospitalized for acute bronchiolitis in our Pediatric Units of Chivasso, Cirié, and Ivrea in Piedmont, Northern Italy, over two consecutive bronchiolitis seasons (September 2021-March 2022 and September 2022-March 2023). Patient-, disease-, and treatment-related variables were analyzed. The probability of therapeutic success (discharge home) was 96% for all patients (93% for RSV vs. 98% for non-RSV patients, p > 0.05). Among 192 patients, 42 infants (22%) underwent high-flow oxygen support (HFNC), and only 8 (4%) needed to be transferred to our hub referral hospital. Factors associated with hub hospital transfer were the age under 1 month and the failure of HFNC. The wide and increasing use of HFNC in pediatric inpatients improved the management of bronchiolitis in Spoke hospitals, reducing transfer to a hub hospital provided with Intensive Care Units.

HSCT with mismatched unrelated donors: Bone marrow versus peripheral blood stem cells sources in pediatric patients.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) from an unrelated HLA-mismatched donor (MMUD) is one of the alternatives where an HLA-matched donor is not found. The aim of this study was to compare bone marrow (BM) versus peripheral blood stem cells (PBSC) as hematopoietic rescue following allogeneic unrelated mismatched stem cell transplantation (MMUD). METHODS: The patients were divided into two groups: 43 pediatric patients were treated with BM and 17 pediatric patients with PBSC. The study was registered at ClinicalTrials.gov NCT04598789. RESULTS: The 3-year Overall Survival (OS) was 74% versus 31% (p = .0011). Transplant related mortality (TRM) was 16% versus 33% (p = .025), and relapse incidence (RI) was 16% versus 35% (p = .005). The day-100 acute Graft-versus-host disease (GvHD) incidence grade II-IV and III-IV was 30% versus 28% (p = NS) and 17% versus 17% (p = NS). The 3-year chronic GvHD incidence was 22% versus 33% (p = NS). CONCLUSION: Despite all the limits of this retrospective study we were able to show how the combination of BM and ATG is able to prevent GvHDs and guarantee a high OS. Future studies addressing the issue of a post-transplant cellular therapy approach may potentially reduce relapses when GvHD is absent.

Post-Transplant Cyclophosphamide and Tacrolimus-Mycophenolate Mofetil Combination Governs GVHD and Immunosuppression Need, Reducing Late Toxicities in Allogeneic Peripheral Blood Hematopoietic Cell Transplantation from HLA-Matched Donors.

Combined direct antineoplastic activity and the long-lasting immunological effects of allogeneic hematopoietic cell transplant (HCT) can cure many hematological malignancies, but broad adoption requires non-relapse mortality (NRM) rates and graft-versus-host disease (GVHD) control. Recently, posttransplant cyclophosphamide (PTCy) given after a bone marrow transplant significantly reduced GVHD-incidence, while PTCy given with tacrolimus/mofetil mycophenolate (T/MMF) showed activity following allogeneic peripheral blood stem cell transplantation (alloPBSCT). Here, we report the experience of a larger cohort (85 consecutive patients) and expanded follow-up period (03/2011-12/2019) with high-risk hematological malignancies who received alloPBSCT from Human-Leukocyte-Antigens HLA-matched unrelated/related donors. GVHD-prophylaxis was PTCy 50 mg/kg (days+3 and +4) combined with T/MMF (day+5 forward). All patients stopped MMF on day+28 with day+110 = median tacrolimus discontinuation. Cumulative incidences were 12% for acute and 7% for chronic GVHD- and no GVHD-attributed deaths. For surviving patients, the 12, 24, and 36-month probabilities of being off immunosuppression were 92, 96, and 96%, respectively. After a 36-month median follow-up, NRM was 4%; median event-free survival (EFS) and overall survival (OS) had yet to occur. One- and two-year chronic GVHD-EFS results were 57% (95% CI, 46-68%) and 53% (95% CI, 45-61%), respectively, with limited late infections and long-term organ toxicities. Disease relapse caused the most treatment failures (38% at 2 years), but low transplant toxicity allowed many patients (14/37, 38%) to receive donor lymphocyte infusions as a post-relapse strategy. We confirmed that PTCy+T/MMF treatment effectively prevented acute and chronic GVHD and limited NRM to unprecedented low rates without loss of disease control efficacy in an expanded patient cohort. This trial is registered at U.S. National Library of Medicine as #NCT02300571.

CD34+ selected peripheral blood Stem Cell Boost (SCB) for Poor Graft Function (PGF) or mixed chimerism in pediatric patients, after hematopoietic stem cell transplantation: Results of a retrospective multicenter study.

BACKGROUND: PGF is historically associated with high morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: In this study, we report our multicenter experience on stem cell boost (SCB) for PGF, or incomplete donor engraftment, in 16 pediatric patients. Donors were HLA-matched siblings (n = 4), unrelated donors (n = 11), or haploidentical family members (n = 1). Ten patients had two-lineage cytopenia, 5 had one-lineage cytopenia, and 1 had poor immunological reconstitution together with a low percentage of donor cell engraftment. A median of 6.6x106 selected CD34+/Kg was infused after 194 days from allo-HSCT (48-607). RESULTS: In 4 out of 5 patients, one-lineage cytopenia was resolved, while among the 10 patients with two-lineage cytopenia, 4 resolved both cytopenia, 5 resolved one-lineage, and one did not respond. All patients reverted their mixed chimera to full donor chimera. OS was 56%, transplant-related mortality (TRM) 32%, and RI 12%. The main causes of failure were related to infections with 4 out of 7 deaths caused by this. CONCLUSIONS: SCB may rescue over 50% of patients with PGF after allo-HSCT. An earlier treatment may reduce the infectious complications and improve survival.

Steroid-refractory acute graft-versus-host disease graded III-IV in pediatric patients. A mono-institutional experience with a long-term follow-up.

aGvHD remains a major obstacle to successful HSCT. We report our experience on steroid-refractory aGvHD III and IV from 1989 to 2017. Ninety patients with aGvHD III or IV were stratified according to the HSCT year: 1989-1998, 1999-2007, and 2008-2017 and to aGvHD extension (GvHD III vs IV) and finally the probability of OS, RI, and TRM was calculated accordingly. aGvHD III patients had a substantial improvement over time: day 100 OS raised from 64% (95% CI 39-89) in the first cohort to 100% in the latest (P = .022), and it was mainly due to a reduction of TRM (it was 28% [95% CI 12-65] in the first cohort to 0% in the latest (P = .01). The aGvHD IV patients did not present a significant improvement. Day 100 OS was 42% (95% CI 16-68) in the first group and 54% (95% CI 25-83) in the year 2008-2017 (P = NS), and the day-100 TRM was very similar (it was 57% [95% CI 36-90] in the first cohort and 45% [95% CI 23-89] in the latest (P = NS). We report significant improvements in OS and TRM in patients diagnosed with grade III aGvHD. Patients with the most severe aGvHD appear to have no or fewer benefits on long-term outcomes.

Transplantation Induces Profound Changes in the Transcriptional Asset of Hematopoietic Stem Cells: Identification of Specific Signatures Using Machine Learning Techniques.

During the phase of proliferation needed for hematopoietic reconstitution following transplantation, hematopoietic stem/progenitor cells (HSPC) must express genes involved in stem cell self-renewal. We investigated the expression of genes relevant for self-renewal and expansion of HSPC (operationally defined as CD34+ cells) in steady state and after transplantation. Specifically, we evaluated the expression of ninety-one genes that were analyzed by real-time PCR in CD34+ cells isolated from (i) 12 samples from umbilical cord blood (UCB); (ii) 15 samples from bone marrow healthy donors; (iii) 13 samples from bone marrow after umbilical cord blood transplant (UCBT); and (iv) 29 samples from patients after transplantation with adult hematopoietic cells. The results show that transplanted CD34+ cells from adult cells acquire an asset very different from transplanted CD34+ cells from cord blood. Multivariate machine learning analysis (MMLA) showed that four specific gene signatures can be obtained by comparing the four types of CD34+ cells. In several, but not all cases, transplanted HSPC from UCB overexpress reprogramming genes. However, these remarkable changes do not alter the commitment to hematopoietic lineage. Overall, these results reveal undisclosed aspects of transplantation biology.

Outcome of Relapsed Pediatric Patients After Second Allogeneic Hematopoetic Stem Cell Transplantation: A Retrospective Study From a Single Institution.

Prognosis of relapsed leukemia patients after second allogeneic hematopoietic stem cell transplantation (HSCT2) is historically considered very poor. We report the outcome of 18 pediatric patients after failure of HSCT2. The 2-year overall survival was 26% (95% confidence interval [CI], 6-47). The lymphoid malignancies were associated with better survival (40% [95% CI, 12-68]) than myeloid malignancies (0%, P=0.002), together with time to relapse after the HSCT2 (≥5 mo: 44% [95% CI, 12-76] vs. 0% for patients who relapsed within 5 mo from HSCT2, P=0.005), other factors such as sex, donor type, conditioning regimen, and graft versus host disease prophylaxis did not have statistical significance. When the multivariate analysis was carried out, 2 independent protective factors were identified: the lymphoid malignancies and the graft versus host disease 0 to I after HSCT2. When we look at the treatments, patients receiving blinatumomab after relapse got benefit in terms of overall survival and, more importantly, with a long-term control of acute lymphoblastic leukemia.

Invasive mucormycosis in children with cancer: A retrospective study from the Infection Working Group of Italian Pediatric Hematology Oncology Association.

BACKGROUND: Invasive mucormycosis is a rare but frequently fatal fungal disease. The acute and rapidly progressive evolution causes unfavourable outcome in 22%-59% of patients and its treatment represents a clinical challenge, especially in immunocompromised patients. Current data in paediatric oncological patients are limited. OBJECTIVES: The infection Working Group of the Italian Association of Pediatric Hematology and Oncology (AIEOP) analysed the episodes of invasive mucormycosis occurred between 2009 and 2016. PATIENTS: Fifteen cases of proven mucormycosis (male/female 8/7; median age 14.1 years, range 7.7-18.6) were reported after chemotherapy for acute leukaemia and lymphoma (12) and allogeneic stem cell transplantation (3). The aetiology was Rhizopus oryzae 4, Lichtheimia corymbifera 3 and Mucor spp. 8. RESULTS: Paranasal sinus was the primary site of infection in 14/15 patients combined with orbital involvement (9), central nervous system (8), lung (4), thyroid gland and kidney (1). All patients received liposomal Amphotericin B (L-AmB) (3-10 mg/kg), with surgical debridement in 14/15 cases. Eleven patients received maintenance treatment with posaconazole (9) or isavuconazole (2). Eight out of fifteen patients (53.3%) died, after 3-6 months. CONCLUSIONS: Mucormycosis involved mainly the sinu-orbital site and affected children >10 years. Despite aggressive treatment with high-dose L-AmB and timely surgical debridement, the mortality rate remains still high.

In Vitro Mesenchymal Progenitor Cell Expansion is a Predictor of Transplant-related Mortality and acute GvHD III-IV After Bone Marrow Transplantation in Univariate Analysis: A Large Single-Center Experience.

Mesenchymal stromal cells (MSCs) are multipotent stem cells able to differentiate into mesenchymal origin tissue and support the growth of hematopoietic stem cells. In order to understand the role of MSCs infused in bone marrow grafts, 53 consecutive patients were analyzed for engraftment, acute and chronic graft-versus-host disease (GvHD), transplant-related mortality (TRM), relapse incidence, and overall survival. The MSC content was measured as MSC expansion at the second passage. When in vitro-expanded MSC (cumulative population doubling at second passage, cPDp2) values were stratified according to the median value (2.2-fold increase), the univariate analysis showed a significant difference in TRM (23% vs. 3.8%, P=0.05.) and in acute GvHD III-IV incidence (12% vs. 4%, P=0.04), while the multivariate analysis did not confirm its independent role. No clinical parameters in donors and recipients were identified as predictors of cPDp2 expansion. Our study suggests a role for short-term ex vivo-expanded MSCs in reduced aGVHD III-IV incidence and TRM in univariate analysis. A multicenter, larger study is warranted to confirm these data.

A survey on incidence and management of adenovirus infection after allogeneic HSCT.

To determine the current practices on the management of Adenovirus (ADV) infection after allogenic stem cell transplantation, a survey was undertook among EBMT centres. The response rate was 20% (91/446): 46% were adult, 44% were paediatric and 10% were mixed centres, respectively. The overall incidence of ADV infection was 7.1%: 4.1% in adult, 15.4% in paediatric, and 3.6% in mixed population. The determination of ADV-DNA in biological samples was used in 96% of centres; 58% of them monitored asymptomatic patients with a frequency of twice a week in 9%, once a week in 45%, every two weeks in 4% of centres. The treatment of ADV infection was mainly based on the administration of cidofovir (87%), being the schedule of 5 mg/kg/week with probenecid the most used, and the reduction of immunosuppression (84%). The threshold of ADV-DNAemia to start cidofovir in high-risk patients was most frequently >1000 copies/ml. Innovative treatments, such as brincidofovir and adoptive ADV-cytotoxic-T-lymphocytes, were used in 27% and 20% of centres, respectively. Almost all responding centres consider ADV infection serious enough to deserve testing asymptomatic or symptomatic patients. Cidofovir and reduction of immunosuppression represent the main therapeutic options but one fourth of responding centres experimented novel therapies.

Analysis of Mesenchymal Stromal Cell Engraftment After Allogeneic HSCT in Pediatric Patients: A Large Multicenter Study.

The mesenchymal stem cell (MSC) role after allogeneic hematopoietic stem cell transplantation (HSCT) is still a matter of debate; in particular, MSC engraftment in recipient bone marrow (BM) is unclear. A total of 46 patients were analyzed for MSC and hemopoietic stem cell engraftment after HSCT. The majority of patients had the BM as the stem cell source, and acute leukemia was the main indication for HSCT. Mesenchymal and hematopoietic stem cell chimerism analysis was carried out through specific polymorphic tandemly repeated regions. All patients reached complete donor engraftment; no evidence of donor-derived MSC engraftment was noted. Our data indicate that MSCs after HSCT remain of recipient origin despite the following: (i) myeloablative conditioning; (ii) the stem cell source; (iii) the interval from HSCT to BM analysis; (iv) the underlying disease before HSCT; and (v) the patients' or the donors' age at HSCT.

Multicenter randomized, double-blind controlled trial to evaluate the efficacy of laser therapy for the treatment of severe oral mucositis induced by chemotherapy in children: laMPO RCT.

OBJECTIVES: To demonstrate the efficacy of laser photobiomodulation (PBM) compared to that of placebo on severe oral mucositis (OM) in pediatric oncology patients. The primary objective was the reduction of OM grade (World Health Organization [WHO] scale) 7 days after starting PBM. Secondary objectives were reduction of pain, analgesic consumption, and incidence of side effects. METHODS: One hundred and one children with WHO grade > 2 chemotherapy-induced OM were enrolled in eight Italian hospitals. Patients were randomized to either PBM or sham treatment for four consecutive days (days +1 to +4). On days +4, +7, and +11, OM grade, pain (following a 0-10 numeric pain rating scale, NRS) and need for analgesics were evaluated by an operator blinded to treatment. RESULTS: Fifty-one patients were allocated to the PBM group, and 50 were allocated to the sham group. In total, 93.7% of PBM patients and 72% of sham patients had OM grade < 3 WHO on day +7 (P = 0.01). A significant reduction of pain was registered on day +7 in the PBM versus sham group (NRS 1 [0-3] vs. 2.5 [1-5], P < 0.006). Reduced use of analgesics was reported in the PBM group, although it was not statistically significant. No significant adverse events attributable to treatment were recorded. CONCLUSIONS: PBM is a safe, feasible, and effective treatment for children affected by chemotherapy-induced OM, as it accelerates mucosal recovery and reduces pain.

Second Hematopoietic Stem Cell Transplantation for Post-Transplantation Relapsed Acute Leukemia in Children: A Retrospective EBMT-PDWP Study.

Outcome data were collected from the European Society for Blood and Marrow Transplantation registry on 373 children from 120 centers with relapsed leukemia (214 with acute lymphoblastic leukemia [ALL] and 159 with acute myelogenous leukemia [AML]) who underwent second allogeneic hematopoietic stem cell transplantation (HSCT) between 2004 and 2013. Overall survival (OS) was 38% at 2 years and 29% at 5 years, and leukemia-free survival (LFS) was 30% at 2 years and 25% at 5 years. Median follow-up after second HSCT was 36.4 months in the ALL group and 50.2 months in the AML group. In the ALL group, OS was 43% at 2 years and 33% at 5 years, and LFS was 34% at 2 years and 31% at 5 years. In the AML group, OS was 32% at 2 years and 24% at 5 years, and LFS was 24% at 2 years and 17% at 5 years. The 2-year nonrelapse mortality (NRM) rate was 22% in the ALL group and 18% in the AML group. Favorable prognostic factors (P < .05) for OS and LFS included >12 months between transplantations and chronic graft-versus-host disease after the first HSCT (in both groups), complete response before the second HSCT (ALL group only), and age >12 years (AML group only). Findings were more consistent over time in the ALL group, with no significant differences between 2-year and 5-year rates of relapse, NRM, and LFS. Children with relapsed acute leukemias have a substantial likelihood of long-term survival following second HSCT. Given the many novel targeted and immunomodulation therapies currently under development, it is important to identify specific patient subpopulations that may benefit from a second HSCT compared with those better suited to new approaches.

Prognostic significance of The Wilms' Tumor-1 (WT1) rs16754 polymorphism in acute myeloid leukemia.

Acute myeloid leukemia is a genetically heterogeneous disease characterized by the accumulation of mutations in hematopoietic progenitor cells. For its heterogeneity, prognostic markers are very useful for therapeutic choice. The most important prognostic markers are age, white blood cell count, chromosomal alterations and gene mutations. Recent works have studied the prognostic significance of WT1 polymorphisms and mutations, highlighting the role of SNP rs16754 as a positive prognostic factor in AML patients. Nevertheless, the data are still unclear. To investigate the role of WT1 rs16754 polymorphism in AML, we designed a new tool for the detection using PNA directed PCR Clamping technology. Our data were able to establish a correlation between SNP rs16754 and the clinical outcome. Our results support the hypothesis that rs16754 polymorphism is an independent positive prognostic molecular marker that could be useful for therapeutic choice. In view of this, we described a novel assay faster, more sensitive and cheaper than DNA sequencing. The assay allows evaluating WT1 rs16754 polymorphism in diagnostic routine to improve prognostic information faster and without over-costing for diagnostic laboratories.

A survey on hematology-oncology pediatric AIEOP centres: The challenge of posterior reversible encephalopathy syndrome.

OBJECTIVES: Posterior reversible encephalopathy syndrome (PRES) is one of the most common neurological complications in hematology-oncology pediatric patients. Despite an increasingly recognized occurrence, no clear consensus exists regarding how best to manage the syndrome, because most cases of PRES have reported in single-case reports or small series. Aim of this paper is to identify incidence, clinical features, management, and outcome of PRES in a large series of hematology-oncology pediatric patients. METHODS: The cases of PRES occurred in twelve centers of the Italian Association of Pediatric Hematology and Oncology were reported. RESULTS: One hundred and twenty-four cases of PRES in 112 pediatric patients were recorded with an incidence of 2.1% and 4.7%, respectively, in acute lymphoblastic leukemia in first complete remission and hematopoietic stem cell transplantation (HSCT). The majority of cases occurred after a cycle of chemotherapy rather than after stem cell transplant. PRES after chemotherapy significantly differs from that after HSCT for diagnosis, time of presentation, risk factors, management, and outcome. CONCLUSIONS: This study demonstrates that PRES is a common neurological complication and occurring preferentially in course of induction treatment of some hematologic malignancies, as ALL and after HSCT. It also highlights great clinical differences in the management and outcome in patients with PRES occurring after chemotherapy or after HSCT.

Posaconazole oral dose and plasma levels in pediatric hematology-oncology patients.

BACKGROUND: Posaconazole is a triazole with limited pharmacokinetic information in children. This study assessed the correlation between posaconazole oral solution daily dosage/kg/body weight and trough plasma level. METHODS: A total of 97 hematology-oncology pediatric patients with ≥1 posaconazole plasma concentration level (PPC) assessment in the first 6 weeks after the start of posaconazole treatment were included. RESULTS: Posaconazole was used as prophylaxis in 84 of 97 (87%) patients and as therapy in 13 of 97 (13%). The median daily dose/kg/bw ranged from 10 to 12 mg in the prophylaxis group and 12.5 to 16.5 mg in the therapy group. The median value of PPC for the prophylaxis group was 0.9 and 0.8 µg/mL at the first and second/third determinations, respectively. Posaconazole prophylaxis failed in 4 of 84 patients (5%). The median value of PPC for the therapy group was 1.5 and 1.4 µg/mL at the first/second and the third determination, respectively. Posaconazole-related side effects were reported in 6 patients and all regressed with the suspension of the drug. In the prophylaxis group, the use of proton-pump inhibitors was significantly associated with a lower PPC, P = 0.04. CONCLUSIONS: Posaconazole may be a valuable antifungal agent in children despite the incomplete knowledge of its pharmacokinetic characteristics.

Steroid treatment of acute graft-versus-host disease grade I: a randomized trial.

Patients with acute graft-versus-host disease (GvHD) grade I were randomized to an observation arm (n=85) or to a treatment arm (n=86) consisting of 6-methylprednisolone 1 mg/kg/day, after stratification for age and donor type. The primary end point was development of grade II-IV GvHD. The cumulative incidence of grade II-IV GvHD was 50% in the observation arm and 33% in the treatment arm (P=0.005). However, grade III-IV GvHD was comparable (13% vs 10%, respectively; P=0.6), and this was true for sibling and alternative donor transplants. Moderate/severe chronic GvHD was also comparable (17% vs 9%). In multivariate analysis, an early interval between transplant and randomization (

Expression of the pol gene of human endogenous retroviruses HERV-K and -W in leukemia patients.

The human endogenous retroviruses (HERVs) are a family of endogenous retroviruses that integrated into the germ cell DNA of primates over 30 million years ago. HERV expression seems impaired in several diseases, ranging from autoimmune to neoplastic disorders. The purpose of this study was to evaluate the overall endogenous retroviral transcription profile in bone marrow (BM) samples. A total of 30 paediatric high-risk leukaemia patients (lymphoid and myeloid malignancies) were tested for HERVs virus gene expression. Our findings show that HERV-K expression was significantly higher in leukaemia patients when compared to healthy donors of a similar median age. We observed a significantly high expression of HERV-K in acute lymphoblastic leukemia (ALL) patients. In this study, we also found a relative overexpression of the endogenous retrovirus HERV-K in BM cells from the majority of leukemia samples analyzed, in particular in ALL. This overexpression might be related to lymphatic leukemogenesis and it warrants further investigations.