Association between oral and fecal microbiome dysbiosis and treatment complications in pediatric patients undergoing allogeneic hematopoietic stem cell transplantation.

The oral and gastrointestinal mucosae represent the main targets of the toxic effect of chemo and/or radiotherapy administered during the conditioning regimen before hematopoietic stem cell transplant (HSCT). These harmful consequences and the immunological complications that may occur after the transplant (such as Graft versus Host Disease, GvHD) are responsible for the clinical symptoms associated with mucositis during the aplasia phase, like pain, nausea, vomiting, and diarrhea. These toxicities could play a critical role in the oral and gastrointestinal microbiomes during the post-transplant phase, and the degree of microbial dysbiosis and dysregulation among different bacterial species could also be crucial in intestinal mucosa homeostasis, altering the host's innate and adaptive immune responses and favoring abnormal immune responses responsible for the occurrence of GvHD. This prospective pediatric study aims to analyze longitudinally oral and gut microbiomes in 17 pediatric patients who received allogeneic HSCT for malignant and non-malignant diseases. The oral mucositis was mainly associated with an increased relative abundance of Fusobacteria, and Prevotella species, while Streptococcus descendants showed a negative correlation. The fecal microbiome of subjects affected by cutaneous acute GvHD (aGvHD) correlated with Proteobacteria. Oral mucosal microbiota undergoes changes after HSCT, Fusobacteria, and Prevotella represent bacterial species associated with mucositis and they could be the target for future therapeutic approaches, while fecal microbiome in patients with acute GvHD (aGvHD) revealed an increase of different class of Proteobacteria (Alphaproteobacteria and Deltaproteobacteria) and a negative correlation with the class of Gammaproteobacteria.

Pregnancy and pregnancy outcomes after hematopoietic stem cell transplantation in childhood: a cross-sectional survey of the EBMT Pediatric Diseases Working Party.

STUDY QUESTION: What are the characteristics of patients with conceptions transplanted in childhood and adolescence? SUMMARY ANSWER: Insemination and conception after hematopoietic stem cell transplantation (HCT) in childhood or adolescence was possible, even after myeloablative conditioning regimes, although some patients required reproductive medicine support. WHAT IS KNOWN ALREADY: Preparative regimens of HCT are highly gonadotoxic, which leads to gonadal failure and pubertal development disorders. There are few population-based studies assessing the risk of future infertility in children after HCT. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective study to investigate natural or assisted conceptions and their outcomes in patients <18 years old before their first transplantation who received HCT between 1995 and 2016 and were in the European Society for Blood and Marrow Transplantation (EBMT) registry. Adoptions were excluded from the analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Detailed information concerning pregnancy occurrences and outcomes were obtained by a separate questionnaire. Quantitative variables were presented as medians with their interquartile range (IQR) or range, and categorical variables were presented as frequencies and percentages. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 62 988 pediatric patients received a first HCT in EBMT centers between 1995 and 2016. Pregnancy was reported in 406 patients in the database. The median age at transplantation was 15.7 (range: 0.7-18) years, and the median age at declared conception was 25.0 (range: 16.3-38.8) years. Details concerning the first pregnancy and pregnancy outcome were obtained from 99 patients (24%) from the returned questionnaires. The median age at delivery or pregnancy interruption of the females was 23.0 (IQR: 20.8-27) years, with a median time after transplant of 10.7 (IQR: 6.6-15.4) years. Compared with the mean age of healthy women at their first child's birth (29 years old), the transplanted women delivered 5 years earlier (mean: 24.3 years). In terms of conception modality, 13/25 (52%) females conditioned with total body irradiation (TBI) and 50/52 (96%) of those conditioned without TBI conceived naturally. All seven male patients who had been conditioned with TBI achieved fatherhood but required assisted fertilization or used their cryopreserved sperm. In the females, 63/70 (90%) of all conceptions resulted in a live birth, 49/63 (84.5%) were at term and 43/46 (93%) had normal birthweight. Cesarean delivery was performed in 9/61 (15%) especially in women who had received a myeloablative regimen. LIMITATIONS, REASONS FOR CAUTION: In the EBMT pediatric dataset, the age at last follow-up or death was <17 years for 75% of the patients, therefore a longer follow-up for all patients would be necessary to calculate the cumulative incidence of conception for patients transplanted during childhood and allow all patients to realize their reproductive willingness/potential. WIDER IMPLICATIONS OF THE FINDINGS: Reproductive health surveillance and fertility preservation counseling are important in younger transplanted patients. Our results showed that there is a window of opportunity to conceive naturally or with reproductive medicine support. STUDY FUNDING/COMPETING INTEREST(S): Funding was provided by the 'Stiftung für krebskranke Kinder Regio Basiliensis', Basel, Switzerland. All authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

'Real-life' report on the management of chronic GvHD in the Gruppo Italiano Trapianto Midollo Osseo (GITMO).

Several guidelines have been published about management of chronic GvHD (cGvHD), but the clinical practice still remains demanding. The Gruppo Italiano Trapianto di Midollo Osseo (GITMO) has planned a prospective observational study on cGvHD, supported by a dedicated software, including the updated recommendations. In view of this study, two surveys have been conducted, focusing the management of cGvHD and ancillary therapy in cGvHD, to address the current 'real life' situation. The two surveys were sent to all 57 GITMO centers, performing allografting in Italy; the response rate was 57% and 66% of the interviewed centers, respectively. The first survey showed a great disparity especially regarding steroid-refractory cGvHD, although extracorporeal photo-apheresis resulted as the most indicated treatment in this setting. Another challenging issue was the strategy for tapering steroid: our survey showed a great variance, and this disagreement could be a real bias in evaluating outcomes in prospective studies. As for the second survey, the results suggest that the ancillary treatments are not standardized in many centers. All responding centers reported a strong need to standardize management of cGvHD and to participate in prospective trials. Before starting observational and/or interventional studies, a detailed knowledge of current practice should be encouraged.

Fertility preservation practices in pediatric and adolescent cancer patients undergoing HSCT in Europe: a population-based survey.

Chemotherapy and irradiation can affect the gonads, leading to impairment of pubertal development and/or infertility. Fertility preservation (FP) is therefore a crucial endeavor in hematopoietic stem cell transplantation (HSCT) because of the severe impact of infertility on the quality of life of long-term survivors. Despite the existence of different international guidelines, FP counseling and procedures are not routinely implemented as part of patient care. We present herein a survey conducted by the Pediatric Working Party of the European Society for Blood and Marrow Transplantation (EBMT), which aims to analyze and compare different FP practices for children and adolescents across EBMT centers in 2013. A total of 177 pediatric centers reporting to the EBMT were contacted; of this number, 38 centers (21%) located in 16 different countries responded. These centers reported 834 patients receiving HSCT in 2013 (73% prepubertal), corresponding to 22% of all children (n=3789) undergoing HSCT in EBMT reporting centers. Overall, 39% of the reported patients received counseling and 29% received an FP procedure. The increased need for FP programs, extended education for patient-care teams, and more personal resources and funding emerged from this survey as pivotal factors necessary to support and implement such programs.

Incidence and severity of crucial late effects after allogeneic HSCT for malignancy under the age of 3 years: TBI is what really matters.

Younger children are considered to be more vulnerable to late effects (LE), which prompted us to study LE in patients after haematopoietic stem cell transplantation (HSCT) for a haematological malignancy before the age of 3. In this multicentre EBMT study, cumulative incidence (CI) and severity of endocrine LE, central nervous system complications and secondary malignancies at 5, 10, 15 and 20 years of follow-up were assessed. Risk factors (RF) like gender, diagnosis, age at and year of HSCT, TBI- or chemo-conditioning and GVHD were analysed. CI of any LE was 0.30, 0.52, 0.66 and 0.72 at 5, 10, 15 and 20 years after HSCT, respectively. In 25% of the patients, LE were severe at a median follow-up of 10.4 years. In multivariate analysis, only TBI was a RF for having any LE and for thyroid dysfunction and growth disturbance. Female gender was a RF for delayed pubertal development. Some more insight could be gained by descriptive analysis regarding the role of TBI and GVHD on the severity of LE. Although only five selected LE have been studied and median follow-up is relatively short, the incidence and severity of these LE are considerable but not different from what has been found in older children and TBI is the main RF.

Paediatric reduced intensity conditioning: analysis of centre strategies on regimens and definitions by the EBMT Paediatric Diseases and Complications and Quality of Life WP.

The aim of this analysis was to explore the diversity of reduced intensity conditioning (RIC) in paediatric allo-SCT in daily practice across Europe. Data from the European Group for Blood and Marrow Transplantation (EBMT) Promise database from 1994 to 2008 were supplemented by a survey of EBMT centres performing paediatric allo-SCT on the current policy asking for the underlying diseases and for the drug combinations. Records from 161 centres from 30 countries were analysed and 139 various RIC regimens were reported. More centres applied RIC for malignant rather than for non-malignant diseases. In general, fludarabine (FLU)-based regimens predominated except for BU-based regimens in myeloid malignancies and haemoglobinopathies. Treosulfan (TREO) was mainly applied for unspecified malignant diseases and for haemophagocytic diseases. FLU-based regimens revealed the greatest number of different combinations. Correlating the number of regimens with the number of treating centres revealed the lowest variety in FLU and the highest variety in TBI and TREO. FLU/melphalane and FLU/CY were the most frequent combinations. This extreme heterogeneity in RIC may influence both the efficacy and the safety of the procedures, which requires further investigation. Optimization and standardization of RIC is the final goal to provide a platform for future prospective studies.

Allogeneic stem cell transplantation for patients with advanced rhabdomyosarcoma: a retrospective assessment.

BACKGROUND: Allogeneic haematopoietic stem cell transplantation (allo-SCT) may provide donor cytotoxic T cell-/NK cell-mediated disease control in patients with rhabdomyosarcoma (RMS). However, little is known about the prevalence of graft-vs-RMS effects and only a few case experiences have been reported. METHODS: We evaluated allo-SCT outcomes of 30 European Group for Blood and Marrow Transplantation (EBMT)-registered patients with advanced RMS regarding toxicity, progression-free survival (PFS) and overall survival (OS) after allo-SCT. Twenty patients were conditioned with reduced intensity and ten with high-dose chemotherapy. Twenty-three patients were transplanted with HLA-matched and seven with HLA-mismatched grafts. Three patients additionally received donor lymphocyte infusions (DLIs). Median follow-up was 9 months. RESULTS: Three-year OS was 20% (s.e.±8%) with a median survival time of 12 months. Cumulative risk of progression was 67% (s.e.±10%) and 11% (s.e.±6%) for death of complications. Thirteen patients developed acute graft-vs-host disease (GvHD) and five developed chronic GvHD. Eighteen patients died of disease and four of complications. Eight patients survived in complete remission (CR) (median: 44 months). No patients with residual disease before allo-SCT were converted to CR. CONCLUSION: The use of allo-SCT in patients with advanced RMS is currently experimental. In a subset of patients, it may constitute a valuable approach for consolidating CR, but this needs to be validated in prospective trials.

Relationship between clinical and BK virological response in patients with late hemorrhagic cystitis treated with cidofovir: a retrospective study from the European Group for Blood and Marrow Transplantation.

To investigate the relationship between clinical response and modification of BK viremia, we assessed retrospectively 32 cases of hemorrhagic cystitis (HC) after allogeneic hematopoietic SCT that were treated with i.v. cidofovir (CDV). They were 22 men (69%) and 10 women (31%) with a median age of 24 years, range 3-62. The median number of CDV doses was 3, range 1-8, and the treatment lasted for a median of 3 weeks, range 1-10. Clinical improvement of HC was observed in 27 patients (84%). In 12 of 32 episodes (37.5%), BK viremia was determined before every CDV administration and a complete clinical response was observed in 10 of 12 patients (83%), the reduction of BK viremia load being 1 log by 2 weeks after starting CDV. Nephrotoxicity related to CDV was observed in nine patients. Among 26 patients with 100-day follow-up, 4 of 4 patients who had a complete clinical response by 30 days were alive vs 16 of 22 (73%) who did not have the resolution of HC in this time frame. We conclude that in patients with HC, the response to CDV treatment is usually associated with a significant reduction of BK viremia load.

Safety of conversion from twice-daily tacrolimus (Prograf) to once-daily prolonged-release tacrolimus (Advagraf) in stable liver transplant recipients.

Nonadherence to immunosuppressive regimens among solid organ transplantation to range has been estimated from 15% to 55%. This problem has been identified as a leading cause of preventable graft loss. Tacrolimus once daily Advagraf has been developed to provide a more convenient dosing regimen to improve adherence. The aim of this study was to analyze the safety of a 1:1 dose conversion from twice-daily tacrolimus (Prograf) to Advagraf in 36 stable liver transplant recipients. The tacrolimus whole blood trough level at T0 was 6.7 +/- 2.9 ng/mL with a daily dose of 3.7 +/- 1.8 mg. The mean tacrolimus blood trough levels at T1 (7 days) and T2 (14 days) were 5.8 +/- 2.5 and 5.8 +/- 1.8 ng/mL with mean daily doses of 3.9 +/- 1.9 and 4.1 +/- 1.8 mg, respectively. There was no significant difference between T0, T1, and T2, either for tacrolimus blood trough levels or for tacrolimus daily dosages. Liver and renal function tests remained stable; no episodes of acute rejection were encountered after the conversion. A switching policy using a dose ratio of 1:1 from twice-daily tacrolimus to once-daily prolonged-release tacrolimus was safely applied to stable liver transplant recipients.

Performance of the galactomannan antigen detection test in the diagnosis of invasive aspergillosis in children with cancer or undergoing haemopoietic stem cell transplantation.

Serum galactomannan (GM) antigen detection is not recommended for defining invasive aspergillosis (IA) in children undergoing aggressive chemotherapy or allogeneic haemopoietic stem cell transplantation (HSCT). The ability of the GM test to identify IA in children was retrospectively evaluated in a cohort of children. Test performance was evaluated on samples that were collected during 195 periods at risk of IA. Proven IA was diagnosed in seven periods, all with positive GM test results (true positives, 4%), and possible IA was diagnosed in 15 periods, all with negative GM test results (false negatives, 8%). The test result was positive with negative microbiological, histological and clinical features in three periods (false positives, 1%), and in 170 periods it was negative with negative microbiological, histological and clinical features (true negatives, 87%). The sensitivity was 0.32 and the specificity was 0.98; the positive predictive value was 0.70 and the negative predictive value was 0.92. The efficiency of the test was 0.91, the positive likelihood ratio was 18.3, and the negative likelihood ratio was 1.4. The probability of missing an IA because of a negative test result was 0.03. Test performance proved to be better during at-risk periods following chemotherapy than in periods following allogeneic HSCT. The GM assay is useful for identifying periods of IA in children undergoing aggressive chemotherapy or allogeneic HSCT.

Viral-load and B-lymphocyte monitoring of EBV reactivation after allogeneic hemopoietic SCT in children.

EBV-associated post transplant lymphoproliferative disease (EBV-PTLD) is a life-threatening complication that may occur after hemopoietic SCT. We prospectively screened 80 children on a weekly basis using nested quantitative PCR to evaluate EBV genome copies. EBV viral load <1000 copies per 10(5) PBMC was observed in 63% of transplants, whereas it was between 1000 and 9999 copies per 10(5) PBMC in 13%, and between 10 000 and 19 999 in 10%, with no significant increase in percentage of CD20+ lymphocytes. Viral load reached > or = 20 000 copies per 10(5) PBMC in 14% of patients, and rituximab was administered to 75% of them. None of the patients except one developed a lymphoproliferative disease. Our study found that only 13% of unrelated donor HSCT recipients had a very high risk of EBV-PTLD defined as > or = 20 000 geq per 10(5) PBMC associated with an increase in CD20+ lymphocyte. We suggest that rituximab could be administered in the presence of very high levels of EBV-DNA viral load or in the presence of mid levels of EBV-DNA viral load associated with an increase in the percentage of CD20+ lymphocytes. Through this approach, we significantly reduced the number of patients treated with rituximab, and consequently the acute and chronic adverse events related to this treatment.

Hepatitis B reactivation in allogeneic hemopoietic stem cell transplantation setting: a pediatric experience.

Reactivation of HBV is a well known complication in patients undergoing HSCT. Lamivudine treatment appears to prevent hepatitis B virus reactivation and to decrease the mortality in at risk HSCT patients. We describe HBV reactivation occurred in three allogeneic HSCT pediatric patients coming from Eastern Europe, one of whom was successfully treated with lamivudine. Our experience confirms that HBV-DNA may persist as intra-hepatic infection or in extra-hepatic sites and that HBV reactivation may appear during immunodepression. Careful and complete screening for HBV markers is mandatory before HSCT, especially in children coming from countries at risk for HBV. Furthermore, a treatment with lamivudine could also represent an efficacious prophylaxis in pediatric patients to avoid HBV reactivation and to decrease the development of severe hepatic disease.

Daclizumab as useful treatment in refractory acute GVHD: a paediatric experience.

GVHD remains a serious complication after allogeneic SCT. We describe 13 paediatric patients treated with daclizumab for refractory acute GVHD (aGVHD). After 30 days of daclizumab administration, all patients with cutaneous aGVHD reached complete response. Among patients with gastrointestinal disease, 50 and 30% had complete and partial response, respectively, whereas 11 and 55% of patients with hepatic aGVHD achieved CR and PR, respectively. Overall, complete (46%) and partial (46%) responses were demonstrated in 92% of our patients, whereas the remaining patients (8%) were nonresponders. No life-threatening infectious episodes were recorded within 100 days from transplant in this selected group of paediatric patients. Overall 46% of patients were alive at a median of 461 days from SCT, but 50% of them developed chronic GVHD. In our experience, daclizumab proved to be a useful and safe treatment for refractory and steroid-resistant/dependent aGVHD, in particular for cutaneous and low-moderate intestinal involvement.

Assessing the risk of transplant-related complications and individually tailoring the HSCT procedure in children and adolescents--is it possible?

Children surviving after haematopoietic SCT (HSCT) are a growing population that need to keep their health status under control. They may experience early and late complications that are related to transplant procedures and to treatments administered before HSCT. Monitoring transplant-related complications is mandatory, especially during the child's growth. The purpose of this report is to define preassessment in patients who are candidates for HSCT to identify any pretransplant, comorbid conditions and to individually tailor the HSCT procedure, whenever possible.

Anti-varicella-zoster vaccination in contacts of children receiving antineoplastic chemotherapy: a prospective pilot study.

Varicella may be a severe infection in children with malignancy. Varicella vaccination is either not recommended for immunocompromised children or it requires temporary discontinuation of immunosuppression. We prospectively evaluated the feasibility of a varicella vaccination programme of household contacts of varicella-negative children receiving antineoplastic chemotherapy. From April 2004 to April 2005, 207 children were evaluated; in 49 (24 percent) the attending physicians collected no history about previous varicella and performed no serological evaluation before any transfusion. Among the 158 patients with complete history and/or a screening test, 51 (32 percent) were negative, with a total of 110 household contacts eligible for the study. Of these, 13 (12 percent) subjects resulted negative for varicella. In three of them vaccination was not performed due to parental refusal. This study demonstrates the difficulties in implementing a varicella vaccination programme targeting negative household contacts of immunocompromised children. The attitude of paediatric oncologists and parental refusal currently represent the main challenges against the complete success of this strategy in countries where VZV vaccination is not inserted in the general vaccination programme.

Rare viral infections in children receiving hemopoietic stem cell transplant.

Viral infections are a rare complication in autologous hemopoietic stem cell transplant (HSCT) recipients but represent a frequent cause of disease after allogeneic HSCT. In the last years, there has been an increase in the number of viral diseases observed in these patients. This fact may be at least partially due to an improvement in diagnostic facilities, but the increasing number of transplant procedures and the more severe immunosuppression may also have played an important role.

Invasive mycoses in children receiving hemopoietic SCT.

Invasive mycoses represent a rare but severe complication following hemopoietic SCT (HSCT) in children. Their incidence is related to the type of donor, being higher after allogeneic transplant, especially from alternative donors. Moreover, the incidence of invasive mycoses varies in the different post transplant phases. Neutropenia, lymphopenia, GvHD, high-dose steroids or other immunosuppressive drugs represent well-known risk factors. The clinical features of invasive mycoses after HSCT in children are similar to those observed in adults, and the diagnostic tools, including Aspergillus galactomannan antigen detection, are feasible also in pediatrics. Mortality due to invasive mycoses after HSCT in children is high.