Prevention of infectious complications in pediatric HSCT

Comparing between HLA-matched sibling donor allogenic HSCT and non-sibling matched related donor allogenic HSCT outcome in pediatric patients; single center retrospective study

BACKGROUND

Extended family donor search other than siblings may yield an HLA matched donor in communities with high rate of consanguinity. The outcome of patients who are transplanted from non-sibling matched related donors (NS-MRD) including engraftment and graft versus host disease (GVHD) are scarce in comparison with matched sibling donor (MSD).

METHODS

We retrospectively reviewed the outcome of all our pediatric hematopoietic stem cell transplantation (HSCT) patients who had non-sibling matched related donor and controlled them with matched sibling donor HSCT (based on age, indication of HSCT, conditioning regimen, GVHD prophylaxis, serotherapy, stem cell source and cytomegalovirus status).

RESULTS

A total of 76 patients were reviewed during study period. Thirty patients (39.5%) in NS-MRD arm and 46 patients in MSD (60.5%) were identified after matching in age, disease, and conditioning regimens. All patients had similar approach including stem cell source and GVHD prophylaxis (CNI + 2nd agent). Out of the NS-MRD group, 18 patients (59%) had one of their parents as a donor and the rest as second degree relatives. Both groups were equally distributed and were homogeneous. Both groups had no statistically significant difference in outcome including engraftment, GVHD and Chimerism tests results. GVHD was seen in (13%) NS-MRD patients compared to (11%) in MSD patients. All patients remain alive with median follow up of 1249 days (431-3525).

CONCLUSIONS

This study showed no significant difference in allogenic HSCT outcomes between matched sibling donors and non-sibling matched related donors and support using the same management approach in terms of conditioning therapy, GVHD prophylaxis, and serotherapy only if indicated.

A comparison of four drug-drug interaction databases for patients undergoing haematopoietic stem cell transplantation

WHAT IS KNOWN AND OBJECTIVE

Patients who have undergone haematopoietic stem cell transplantation are prone to drug-drug interactions due to polypharmacy. Drug-drug interaction databases are essential tools for identifying interactions in this patient group. However, drug-drug interaction checkers, which help manage interactions, may have disagreements about assessing the existence or severance of the interactions. The study aimed to determine differences among popular drug-drug interaction databases from several angles for patients who underwent haematopoietic stem cell transplantation.

METHODS

The 21-day treatment sheets of one hundred patients who underwent haematopoietic stem cell transplantation were examined in two subscription-based (Uptodate and Micromedex) and two open-access databases (Drugs.com and Epocrates) in terms of several categories two years in a row. Statistical analysis was utilized to understand the compatibility of databases in terms of severity scores, evidence levels, given references, and word counts in interaction reports. Fleiss' and Cohen's kappa statistics were used to analyse the databases' agreement levels.

RESULTS AND DISCUSSION

A total of 1393 and 1382 different drug-drug interactions were detected in subsequent versions of the databases, namely the 2021 and 2022 versions. The Fleiss kappa overall agreement among databases was slight. Uptodate and Micromedex showed fair agreement, and other database pairs showed slight agreement in severity ratings.

CONCLUSION

There was a poor agreement among databases for interactions seen in bone marrow transplantation patients. Therefore, it would be safer to use more than one database in daily practice. Further work needs to be done to understand the agreement level of databases for different types of interactions.

Analysis of incidence and risk factors of the multidrug resistant gastrointestinal tract infection in children and adolescents undergoing allogeneic and autologous hematopoietic cell transplantation: a nationwide study

The aim of this multi-center study was to evaluate the incidence, clinical course, and risk factors for bacterial multidrug-resistant (MDR) gastrointestinal tract infections (GTI) among children undergoing allogeneic and autologous hematopoietic cell transplantation. A total number of 175 pediatric patients (aged 1–18 years), transplanted between January 2018 and December 2019, who were tested for bacterial colonization/infection were enrolled into this multi-center analysis. Episodes of MDR GTI occurred in 77/175 (44%) patients. In multivariate analysis for higher GTI incidence, the following factors were significant: matched-unrelated donor (MUD) transplantation, HLA mismatch, presence of graft-versus-host disease (GVHD), and gut GVHD. The most common GTI were Clostridium difficile (CDI), multidrug-resistant Enterobacteriaceae (Klebsiella pneumoniae, Escherichia coli extended-spectrum β-lactamase), and Enterococcus HLAR (high-level aminoglycoside-resistant). No MDR GTI–attributed deaths were reported. MDR GTI is a frequent complication after HCT among children, causes prolonged hospitalization, but rarely contributes to death. We identified risk factors of MDR GTI development in children, with focus on GVHD and unrelated donor and HLA mismatch. We conclude that the presence of Clostridiales plays an important anti-inflammatory homeostatic role and decreases incidence of GVHD or alleviate its course.

Infectious Complications in Paediatric Haematopoetic Cell Transplantation for Acute Lymphoblastic Leukemia: Current Status

Haematopoietic stem cell transplantation (HSCT) in paediatric patients with acute lymphoblastic leukaemia (ALL) is associated with a variety of infectious complications which result in significant morbidity and mortality. These patients are profoundly immunocompromised, and immune reconstitution after HSCT generally occurs in astrictly defined order. During the early phase after HSCT until engraftment, patients are at risk of infections due to presence of neutropenia and mucosal damage, with Gramme-positive and Gramme-negative bacteria and fungi being the predominant pathogens. After neutrophil recovery, the profound impairment of cell-mediated immunity and use of glucocorticosteroids for control of graft-vs.-host disease (GvHD) increases the risk of invasive mould infection and infection or reactivation of various viruses, such as cytomegalovirus, varicella zoster virus, Epstein-Barr virus and human adenovirus. In the late phase, characterised by impaired cellular and humoral immunity, particularly in conjunction with chronic GvHD, invasive infections with encapsulated bacterial infections are observed in addition to fungal and viral infections. HSCT also causes a loss of pretransplant naturally acquired and vaccine-acquired immunity; therefore, complete reimmunization is necessary to maintain long-term health in these patients. During the last two decades, major advances have been made in our understanding of and in the control of infectious complications associated with HSCT. In this article, we review current recommendations for the diagnosis, prophylaxis and treatment of infectious complications following HSCT for ALL in childhood.

Adenovirus infection among pediatric patients with cancer and in pediatric recipients of hematopoietic stem cell: A multicenter nationwide study

The aim was to evaluate the incidence, clinical course, and outcome of adenoviral infection (AdVI) in pediatric patients diagnosed and treated due to cancer and in pediatric recipients of hematopoietic stem cell. Over a 72-month period, all-in 5599 children with cancer: 2441 patients with hematological malignancy (HM) and 3158 with solid tumors (ST), and 971 patients after transplantation: 741 after allogeneic (allo-HSCT) and 230 after autologous (auto-HSCT) were enrolled into the study. Among cancer patients, 67 episodes of AdVI appeared in 63 (1.1%) children, including 45 (1.8%) with HM and 18 (0.6%; P < .001) with ST. Within transplanted patients, AdVIs were responsible for 88 episodes in 81 (8.3%) children (P < .001), including 78 (10.5%) patients after allo-HSCT and 3 (1.3%) after auto-HSCT. Time to develop AdVI was short, especially after allo-HSCT. The most common clinical manifestation in cancer patients was enteritis diagnosed in 63 (94.0%) cases, while among HSCT recipient asymptomatic adenoviremia was found in 36 (40.9%) cases and the most common clinical manifestation was urinary tract infection. Cancer patients with disseminated disease, as well as HSCT recipients with either asymptomatic viremia or disseminated disease, received antiviral treatment. The most commonly used first-line therapy was cidofovir. None of the cancer patients died due to AdVI, while within HSCT recipients three patients developed disseminated adenoviral disease and died despite antiviral treatment. In cancer patients, AdVIs are rare and associated with very good prognosis even without specific treatment. However, in allo-HSCT recipients, disseminated disease with fatal outcome is more likely to occur.

Infectious complications after hematopoietic stem cell transplantation for primary immunodeficiency in children: A multicenter nationwide study

PURPOSE

The aim of this nationwide study was to evaluate the characteristics of bacterial infections (BI), invasive fungal disease (IFD), and viral infections (VI) in pediatric patients with PID after allogeneic hematopoietic stem cell transplantation (allo-HSCT).

PATIENTS AND METHODS

In total, 114 HSCT recipients were enrolled into the study. At least one infectious complication (IC) was diagnosed in 60 (52.6%) patients aged 0.1-17.7 years, that is, 59.5% with SCID and 49.4% with non-SCID.

RESULTS

Among 60 HSCT recipients diagnosed with at least one IC, 188 episodes of infectious complications (EIC) were recorded, that is, 46.8% of BI, 41.5% of VI, and 11.7% of proven/probable IFD. According to PID and HSCT donor type, the incidence of EIC was comparable (P = .679). The localization of infections differed significantly due to PID type (P = .002). After each HSCT donor type, the most common site of infection was GI. Overall, BI caused by Gram-positive strains (59.1%) were prevalent, especially Staphylococcaceae. The multidrug-resistant (MDR) pathogens were diagnosed in 52.3%, especially ESBL + Enterobacteriaceae. The profile of VI was comparable for SCID and non-SCID patients (P = .839). The incidence of IFD was comparable for each PID and HSCT donor type. Survival after infection was 91.5% and was comparable for PID and HSCT donor type.

CONCLUSIONS

The rate of patients diagnosed with IC among pediatric PID-HSCT recipients did not depend on PID type, but rather on HSCT donor type. The localization of IC depended on PID and HSCT donor type. Within bacterial infections, predominated Gram-positive strains and the MDR pathogens were responsible for more than half of EIC.

Hematopoietic stem cell transplantation does not increase the risk of infection-related complications for pediatric patients with Hodgkin and non-Hodgkin lymphomas: A multicenter nationwide study

BACKGROUND

Hodgkin (HL) and non-Hodgkin lymphoma (NHL) represent a spectrum of lymphoid malignancies that are often curable with currently applied treatment regimens; however, 15%-30% of lymphoma patients still suffer from relapsed or refractory (rel/ref) disease. Although hematopoietic stem cell transplantation (HSCT) improves outcomes of second-line therapy for lymphoma in childhood, the complication rates in this group of patients, especially infectious complications (IC), remain unclear.

OBJECTIVE

The aim of this population-based cohort study was a retrospective analysis of incidence, epidemiology and profile of bacterial infections (BI), invasive fungal disease (IFD), and viral infections (VI) in primary or rel/ref lymphoma patients, both HL and NHL.

PATIENTS AND METHODS

We subdivided lymphoma patients into three groups: patients with primary conventional chemotherapy/radiotherapy regimens (group A), patients with rel/ref lymphoma treated with second-line chemotherapy (group B), and rel/ref lymphoma patients who underwent HSCT (group C). The medical records of the patients were biannually reported by each pediatric oncology center, and the data were analyzed centrally.

RESULTS

Within 637 patients with primary lymphoma, at least one IC was diagnosed in 255 (40.0%), among 52 patients with rel/ref lymphoma 24 (46.2%) ICs were observed, and in transplanted group, 28 (57.1%) out of 49 children were diagnosed with IC (P = .151). The distribution of etiology of IC differed between the patient groups (A, B, C), with a predominance of BI in group A (85.6% vs 72.0% and 47.9%, respectively), VI in group C (9% and 16.0% vs 46.6%, respectively), and IFD in group B (5.4% vs 12.0% vs 5.5%, respectively). Overall, 500 (68.0%) episodes of bacterial IC were diagnosed in the entire group. Apart from HL patients treated with chemotherapy, in all the other subgroups of patients Gram-positives were predominant. The rate of multidrug-resistant bacteria was high, especially for Gram-negatives (41.1% in group A, 62.5% in group B, and 84.6% in group C). The infection-related mortality was comparable for each group.

CONCLUSIONS

The incidence of IC was comparable during first- and second-line chemotherapy and after HSCT, but their profile was different for primary or re/ref lymphoma and depended on the type of therapy.

Epidemiology and outcome of invasive fungal disease in children after hematopoietic cell transplantation or treated for malignancy: Impact of national programme of antifungal prophylaxis

The objective of the study was the analysis of incidence and outcome of invasive fungal disease (IFD) in children treated for malignancy (PHO, paediatric hematology-oncology) or undergoing hematopoietic cell transplantation (HCT) over a period of six consecutive years in nationwide study. A total number of 5628 patients with newly diagnosed malignancies and 971 patients after HCT (741 allo-HCT and 230 auto-HCT) were screened for infectious complications in biennial reports. IFD incidence was lower among PHO patients: 8.8% vs 21.2% (P < .0001) and survival from IFD was better: 94.2% vs 84.1% (P < .0001). Auto-HCT patients had lower incidence (10.9% vs 24.4%) and lower mortality than allo-HCT patients. Introduction of national antifungal prophylaxis programme in HCT and acute leukaemia patients decreased incidence of IFD in HCT (from 23.1% to 13.4%) and AML on conventional chemotherapy (from 36% to 23%) but not in ALL patients during chemotherapy. In multivariate analysis, the incidence of IFD was higher in patients after HCT, diagnosed for ALL, AML or NHL, and in patients > 10 years old. Factors contributing to death with infection were as follows: undergoing HCT, diagnosis of acute leukaemia (ALL or AML) and duration of treatment of infection > 21 days. In conclusion, the incidence of IFD in allo-HCT and in AML patients on chemotherapy has decreased after introduction of national programme of antifungal prophylaxis, while the incidence of IFD in ALL patients on chemotherapy did not change significantly. The outcome of IFD both in PHO and HCT patients has largely improved in comparison with historical international data.

Epidemiology, Outcome and Risk Factors Analysis of Viral Infections in Children and Adolescents Undergoing Hematopoietic Cell Transplantation: Antiviral Drugs Do Not Prevent Epstein-Barr Virus Reactivation

Objective

The analysis of epidemiology, risk factors and outcome of viral infections in children and adolescents after hematopoietic cell transplantation (HCT).

Methods

In this multicenter nationwide study a total of 971 HCT procedures (741 allo-HCT; 230 auto-HCT) over a period of 6 years were analyzed.

Results

During this period 801 episodes of viral infections were diagnosed in 442 patients. The incidence of viral infections was 57.9% in allo-HCT and 4.8% in auto-HCT patients. The most frequent infections after allo-HCT were caused by cytomegalovirus (CMV), polyoma BK virus (BKV) and Epstein-Barr virus (EBV). The majority of infections occurred within the first 4 months after allo-HCT and over 80% required pharmacotherapy or symptomatic therapy. The median time of treatment of specific viral infection ranged from 7 (for EBV) to 24 (for CMV) days. The highest mortality was observed in case of CMV infection. The risk factors for viral infections were allo-HCT, acute leukemia, acute and chronic graft versus host disease (a/cGVHD), and matched unrelated donor (MUD)/mismatched unrelated donor (MMUD)-HCT. The risk factor for death from viral infection were CMV-IgG seropositivity in acute lymphoblastic leukemia recipient, and MUD/MMUD-HCT. The incidence of EBV infection requiring pre-emptive treatment with rituximab in allo-HCT children was 19.3%. In 30.8% cases of EBV infection, these episodes were preceded by other viral infection and treated with antivirals, which did not prevent development of EBV-DNA-emia with need of rituximab treatment in 81.5% cases. In 47.7% of these cases, GVHD was a factor enabling development of significant EBV-DNA-emia during antiviral therapy of other infection.

Conclusion

We have shown that antiviral drugs do not prevent EBV reactivation in allo-HCT pediatric patients.

Infection profile in children and adolescents with bone marrow failures treated with allogeneic hematopoietic stem cell transplantation

BACKGROUND

The objective of the study was to analyze the profile of infections in children with BMF following alloHCT.

METHODS

Data of 169 consecutive children with inherited and acquired BMF treated with alloHCT between 2012 and 2017 in Polish pediatric transplant departments were analyzed in registry-based retrospective study, with respect to the type of infection, and clinical outcome.

RESULTS

At least 1 infection was diagnosed in 107/169 patients (60.4%). In total, 182 infections were diagnosed. The most common were VI (96; 52.7%), followed by BI (71; 39.0%), and FI (15; 8.2%), P < .001. The most common etiological factors of VI were as follows: CMV (38.5%), EBV (22.9%), and BK virus (24%); while of BI were as follows: Staphylococcus spp. (17; 23.9%), Enterococcus faecium (10; 14.1%), and Klebsiella pneumoniae (9; 12.7%). No difference was found between the occurrence of infections with respect to donor type, graft source, and conditioning type. GvHD had no impact on the incidence of VI, BI, and FI. Fifteen FI were diagnosed in 12 patients, of which 14 FI were diagnosed in children transplanted for FA. Of total 107 children, 9 died (8.4%), of which 4 (3.7%) due to infections: bacterial sepsis (2) and invasive FI (2).

CONCLUSION

Infections in children with BMF following alloHCT remain an important cause of morbidity. Children with FA had high incidence of FI. In our analysis, aGvHD had no impact on the occurrence on infections, although the study was not strong enough to prove such a difference.

Multidrug-resistant bacterial infections in children undergoing haematopoietic stem cell transplantation over a 6-year period: analysis of the Polish Pediatric Group for Hematopoietic Stem Cell Transplantation

AIMS

Multidrug-resistant (MDR) bacteria are an emerging cause of morbidity and mortality after haematopoietic stem cell transplantation (HSCT). The aim of the study was to analyse the incidence, clinical characteristics and survival from bacterial infections (BI) caused by MDR pathogens in paediatric HSCT recipients.

METHODS AND RESULTS

Among 971 transplanted patients, BI were found in 416 children between the years 2012 and 2017. Overall, there were 883 bacterial episodes, which includes 85·8% after allo-HSCT and 14·2% after auto-HSCT. MDR strains were responsible for half of the total number of bacterial episodes. Over 50% of MDR pathogens were Enterobacteriaceae causing mainly gut infections or urinary tract infections.

CONCLUSIONS

Regarding HSCT type, we did not find differences in the profile of MDR BI between allo- and auto-HSCT recipients. However, survival in MDR and non-MDR infections was comparable.

SIGNIFICANCE AND IMPACT OF THE STUDY

The large sample size enables unique analysis and makes our data more applicable to other paediatric HSCT centres. In the absence of local epidemiological data, presented clinical characteristics of MDR-caused infections may be used to optimize the prophylactic strategies, early identification of infectious complications of MDR aetiology and thus promptly initiate adequate antibiotic therapy and further improve patients' outcome.

Age-dependent determinants of infectious complications profile in children and adults after hematopoietic cell transplantation: lesson from the nationwide study

Incidence and outcome of microbiologically documented bacterial/viral infections and invasive fungal disease (IFD) in children and adults after hematopoietic cell transplantation (HCT) were compared in 650 children and 3200 adults in multicenter cross-sectional nationwide study. Infections were diagnosed in 60.8% children and 35.0% adults, including respectively 69.1% and 63.5% allo-HCT, and 33.1% and 20.8% auto-HCT patients. The incidence of bacterial infections was higher in children (36.0% vs 27.6%; p < 0.0001). Infections with Gram-negative bacteria were more frequent than Gram-positives in adults (64.6% vs 44.8%; p < 0.0001). Outcome of bacterial infections was better in children (95.5% vs 91.4%; p = 0.0011). The IFD incidence (25.3% vs 6.3%; p < 0.0001) and outcome (88.0% vs 74.9%; p < 0.0001) were higher in children. The incidence of viral infections was higher in children after allo-HCT (56.3% vs 29.3%; p < 0.0001), and auto-HCT (6.6% vs 0.8%; p < 0.0001). Outcome of viral infections was better in children (98.6% vs 92.3%; p = 0.0096). Infection-related mortality was 7.8% in children and 18.4% in adults (p < 0.0001). No child after auto-HCT died of infection. Adult age, mismatched transplants, acute leukemia, chronic GVHD, CMV reactivation, infection with Gram-negatives, and duration of infection > 21 days were risk factors for death from infection. In conclusion, pediatric patients have 2.9-fold higher incidence and 2.5-fold better outcome of infections than adults after HCT.

Incidence of Infectious Complications in Children With Acute Lymphoblastic Leukemia Treated With Hematopoietic Stem Cell Transplantation

OBJECTIVE

We analyzed incidence and profile of infections in children with acute lymphoblastic leukemia (ALL) treated with hematopoietic stem cell transplantation (HSCT) in Polish pediatric HSCT departments, over a 2-year period.

PATIENTS AND METHODS

Hospital records of 67 patients, who underwent allogeneic HSCT for ALL, were analyzed retrospectively for microbiologically documented infection: bacterial infection (BI), viral infection (VI), and fungal infection (FI). The majority of patients (40/67; 59.7%) underwent HSCT from matched unrelated donors (MUD).

RESULTS

In total, 84 BI in 31 patients, 93 VI in 50 patients, and 27 FI in 22 patients were diagnosed. No differences were found in the frequency of occurrence of BI according to the type of transplant (P = .16); the occurrence of VI was statistically more frequent in MUD transplant recipients as compared with matched sibling donors (MSD) and mismatched related donors (MMFD; P = .001) and there was a trend in MUD patients for the higher occurrence of FI in comparison with MSD and MMFD transplants (P = .08). Regarding disease status, the occurrence of BI, VI, and FI was statistically more frequent in children who underwent transplantation in their first complete remission (CR1), rather than those who underwent transplantation in ≥CR2 (P < .05). In conclusion, infectious complications are an important cause of morbidity in children with ALL treated with allogeneic HSCT and the incidence of infections is high in this group of patients.

Bacterial infections in pediatric hematopoietic stem cell transplantation recipients: incidence, epidemiology, and spectrum of pathogens: report of the Polish Pediatric Group for Hematopoietic Stem Cell Transplantation

BACKGROUND

Infectious complications are a significant cause of hematopoietic stem cell transplantation (HSCT) failure, especially allogeneic HSCT (allo-HSCT) because of delayed immune reconstitution and graft-versus-host disease (GVHD) occurrence. Identifying the factors responsible for bacterial infections (BI) in patients undergoing HSCT will provide much more effective empirical antimicrobial treatment in this group of patients.

OBJECTIVE

The aim of this study was to evaluate the epidemiology and profile of BI in patients after HSCT in 5 centers of the Polish Pediatric Group for Hematopoietic Stem Cell Transplantation in 2012-2013.

PATIENTS AND METHODS

In 308 HSCT recipients, we retrospectively analyzed 273 episodes of BI in 113 (36.7%) children aged 0.02-22 years (median age: 7 years), 92 after allo-HSCT and 22 after autologous HSCT (auto-HSCT). We assessed incidence of BI in different HSCT types by calculating the Index of Bacterial Infection (IBI) as a ratio of patients with at least 1 BI to all patients who underwent this type of HSCT in the analyzed period. We assessed the profile of BI with particular emphasis on multidrug-resistant organisms, and impact of underlying disease and of graft-versus-host disease on BI episodes.

RESULTS

In the studied group, 273 episodes of BI were diagnosed, including 237 episodes after allo-HSCT and 36 after auto-HSCT. Among allo-HSCT recipients diagnosed with at least 1 BI, the IBI was 0.4 (matched sibling donor-HSCT 0.3; matched donor-HSCT 0.4; mismatched unrelated donor [MMUD]-HSCT 0.8; P = 0.027) and after auto-HSCT 0.3 per 1 transplanted patient. In patient after allo-HSCT because of myelo- or lymphoproliferative diseases and bone marrow failures, the major cause of infections was Enterobacteriaceae, while gram-positive bacteria predominated in the group with primary immunodeficiencies. In all patients after auto-HSCT, the dominant pathogen of BI were Enterobacteriaceae (P = 0.011). Time from each type of HSCT to infection caused by different pathogens did not differ significantly.

CONCLUSIONS

The risk of BI does not depend on the underlying disease, but only on HSCT donor type and is the highest after MMUD-HSCT procedure. The profile of BI depends on the underlying disease and HSCT donor type, but does not depend on the occurrence of acute GVHD. Gram-negative bacteria predominated in patients with myelo- and lymphoproliferative diseases, while in patients with primary immunodeficiencies gram-positive strains were predominant.

Increased risk of infections and infection-related mortality in children undergoing haematopoietic stem cell transplantation compared to conventional anticancer therapy: a multicentre nationwide study

This nationwide multicentre study analysed the epidemiology of bacterial, viral and fungal infections in paediatric haematopoietic stem cell transplantation (HSCT) and paediatric haematology and oncology (PHO) patients over a period of 24 consecutive months, including incidence, hazard risk and outcome of infections as well as occurrence of multidrug-resistant bacteria. During this period, 308 HSCTs were performed and 1768 children were newly diagnosed for malignancy. Compared to PHO, the risk in HSCT patients was significantly higher for all infections (hazard ratio (HR) 2.7), bacterial (HR 1.4), fungal (HR 3.5) and viral (HR 15.7) infections. The risk was higher in allo- than auto-HSCT for bacterial (HR 1.4), fungal (HR 3.2) and viral (HR 17.7) infections. The incidence of resistant bacteria was higher in HSCT than in PHO patients for both G-negative (72.5% vs. 59.2%) and G-positive (41.4% vs. 20.5%) strains. Cumulative incidence of bacterial, fungal and viral infections in HSCT patients was 33.9, 22.8 and 38.3%, respectively. Cumulative incidence of viral infections in allo-HSCT was 28.0% for cytomegalovirus, 18.5% for BK virus, 15.5% for Epstein-Barr virus, 9.5% for adenovirus, 2.6% for varicella zoster virus, 0.9% for influenza, 0.9% for human herpesvirus 6 and 0.3% for hepatitis B virus. Survival rates from infections were lower in HSCT than in PHO patients in bacterial (96.0 vs. 98.2%), fungal (75.5 vs. 94.6%) and most viral infections. In conclusion, the risk of any infections and the occurrence of resistant bacterial strains in allo-HSCT patients were higher than in auto-HSCT and PHO patients, while the outcome of infections was better in the PHO setting.

Live virus vaccines in transplantation: friend or foe?

Solid organ and hematopoietic stem cell transplant recipients may be exposed to diseases which may be prevented through live attenuated virus vaccines (LAVV). Because of their immunosuppression, these diseases can lead to severe complications in transplant recipients. Despite increasing evidence regarding the safety and effectiveness of certain LAVV, these vaccines are still contraindicated for immunocompromised patients, such as transplant recipients. We review the available studies on LAVV, such as varicella zoster, measles-mumps-rubella, influenza, yellow fever, polio, and Japanese encephalitis vaccines in transplant patients. We discuss the current recommendations and the potential risks, as well as the expected benefits of LAVV immunization in this population.

Pain Management for Children during Bone Marrow and Stem Cell Transplantation

Pain management for children during bone marrow and stem cell transplantation is a significant clinical challenge for the health care team. Pain management strategies vary by institution. This paper reports on the use of a pediatric pain management service and patient- and caregiver-controlled analgesia for children undergoing transplant. This 2-year retrospective chart review examined the pain management practices and outcomes of children undergoing bone marrow and stem cell transplants in a large urban teaching hospital during 2008 and 2009. We concluded that patient- and caregiver-controlled analgesia is a well-tolerated modality for pain control during hospitalization for transplantation at this institution.

Neutropenia Precautions for Children Receiving Chemotherapy or Stem Cell Transplantation for Cancer

Infections in children and adolescents with cancer are a significant cause of morbidity and mortality, especially in those receiving chemotherapy who are neutropenic and/or immunocompromised. The aim of this article is to review existing evidence in order to provide a practice recommendation to prevent or minimize infections in neutropenic and/or immunocompromised patients receiving chemotherapy and/or stem cell transplant. Systematic reviews were undertaken and research was graded according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. A variety of interventions are implemented to reduce infections in the neutropenic and/or immunocompromised population; however, few are supported by research evidence. Existing literature should continue to be reviewed to further identify interventions that can influence positive patient outcomes and provide opportunities for individuals in the medical field to work together to improve clinical care.

Vaccination of hematopoietic stem cell transplantation recipients: perspective in Korea

Antibody titers to vaccine-preventable diseases such as tetanus, polio, measles, mumps, and rubella decline within 1-10 years after allogeneic or autologous hematopoietic stem cell transplantation (SCT) if the recipient is not vaccinated. Vaccine-preventable diseases such as pneumococcal diseases, Haemophilus influenzae type b infections, influenza, measles, and varicella can pose an increased risk for SCT recipients. Therefore, after SCT, the recipients should be routinely revaccinated. Vaccination recommendations have previously been developed and published by the European Group of Blood and Marrow Transplantation and the Centers for Disease Control, by the Infectious Diseases Society of America, and by the American Society for Blood and Marrow Transplantation in 2009. Different epidemiologies and strategies have existed in Korea. In 2012, the Korean Society of Infectious Diseases published "Vaccination for Adult" describing the guidelines for vaccination, one of the chapters assigned for vaccination of SCT recipients. The present article reviews the current available vaccination strategies for SCT recipients, their family members, and healthcare workers, with the focus on recent Korean perspectives.

Longitudinal analysis of antibody response to immunization in paediatric survivors after allogeneic haematopoietic stem cell transplantation

The long-term antibody responses to re-immunization in recipients of allogeneic haematopoietic stem cell transplantation (allo-HSCT) have not been well studied. We prospectively and longitudinally evaluated the antibody responses to eight vaccine antigens (diphtheria, tetanus, pertussis, measles, mumps, rubella, hepatitis B, and poliovirus) and assessed the factors associated with negative titres in 210 allo-HSCT recipients at St. Jude Children's Research Hospital. Antibody responses lasting for more than 5 years after immunization were observed in most patients for tetanus (95.7%), rubella (92.3%), poliovirus (97.9%), and, in diphtheria-tetanus-acellular pertussis (DTaP) recipients, diphtheria (100%). However, responses to pertussis (25.0%), measles (66.7%), mumps (61.5%), hepatitis B (72.9%), and diphtheria in tetanus-diphtheria (Td) recipients (48.6%) were less favourable, with either only transient antibody responses or persistently negative titres. Factors associated with vaccine failure were older age at immunization; lower CD3, CD4 or CD19 counts; higher IgM concentrations; positive recipient cytomegalovirus serology; negative titres before immunization; acute or chronic graft-versus-host disease; and radiation during preconditioning. These response patterns and clinical factors can be used to formulate re-immunization and monitoring strategies. Patients at risk for vaccine failure should have long-term follow-up; those with loss of antibody response or no seroconversion should receive booster immunizations.

Food-borne bacteremic illnesses in febrile neutropenic children

Bacteremia following febrile neutropenia is a serious complication in children with malignancies. Preventive measures are currently targeted at antimicrobial prophylaxis, amelioration of drug-induced neutropenia, and nosocomial spread of pathogens, with little attention to community-acquired infections. A retrospective study was conducted at a pediatric oncology center during a 3-year period to identify probable cases of food-borne infections with bacteremia. Twenty-one bacteremic illnesses affecting 15 children receiving chemotherapy or hematopoietic stem cell transplantation were reviewed. Three (14%) episodes were highly suspected of a food-borne origin: a 17-year-old boy with osteosarcoma contracted Sphingomonas paucimobilis septicemia after consuming nasi lemak bought from a street hawker; a 2-year-old boy with acute lymphoblastic leukemia developed Chryseobacterium meningosepticum septicemia after a sushi dinner; a 2-year-old girl was diagnosed with acute lymphoblastic leukemia and Lactobacillus bacteremia suspected to be of probiotic origin. All of them were neutropenic at the time of the infections and the bacteremias were cleared with antibiotic treatment. Food-borne sepsis may be an important, but readily preventable, cause of bloodstream infections in pediatric oncology patients, especially in tropical countries with an abundance of culinary outlets.

The effect of enteral nutrition supplements on serum voriconazole levels

This is the case of a 13-year-old Hispanic boy (34.2 kg, 1.14 m2) who had achieved stable therapeutic levels on voriconazole who later experienced levels reported as ‘none detected’ after the initiation of tube feeds. This case outlines the temporal relationship of the effect of tube feeds on voriconazole serum levels. Based on this information, voriconazole suspension should not be prescribed to patients also receiving supplemental enteral nutrition. In absence of formal animal or human pharmacokinetic studies, it is the recommendation of the author to separate this combination and to be very vigilant about checking serum voriconazole levels in patients on voriconazole suspension and enteral nutrition supplements.

[The Spanish Society of Paediatric Infectious Diseases (SEIP) recommendations on the diagnosis and management of invasive candidiasis]

Candida yeasts are ubiquitous commensals, which can cause opportunistic infection in any location of the body. The source of infection may be both endogenous and exogenous. Invasive candidiasis encompasses different entities ranging from invasive candidiasis to disseminated multiorgan infection. Invasive candidiasis is the third leading cause of nosocomial bloodstream infection and the fourth of all nosocomial infections. It is also the most common invasive fungal infection in non-neutropenic critically ill patients, with a remarkable increase in the last 20 years owing to the increased survival of these patients and to more complex diagnostic, therapeutic and surgical procedures. Its incidence in infants, according to recent reviews, stands at 38.8 cases/100,000 children younger than 1 year. Candida albicans remains the most frequent isolate in invasive infections, although infections caused by other species have risen in the last years, such as C. kruzsei, C. glabrata and C. parapsilosis; the latter causing invasive candidiasis mainly associated with central venous catheter management, especially in neonatal units. The overall mortality of invasive candidiasis is high, with 30-day mortality reaching 20-44% in some series involving paediatric patients. This report provides an update on incidence, epidemiology, clinical presentation, diagnosis, treatment and outcome of invasive infection by Candida spp. in the paediatric patient.

Haematopoietic stem cell transplantation: current concepts and novel therapeutic strategies

INTRODUCTION

Haematopoietic stem cell transplantation (HSCT) is potentially curative for haematological diseases. New developments are improving its applicability and success. Sources of data A literature search was conducted on peripheral blood haematopoietic stem cell (PBHSC) mobilization, umbilical cord blood (UCB) transplantation, reduced intensity conditioning (RIC) and acute graft-versus-host disease (aGVHD).

AREAS OF AGREEMENT

PBHSC mobilization by granulocyte colony-stimulating factor and chemomobilization may fail in up to 30% of patients previously treated with extensive chemotherapy. New mobilization agents, notably the CXCR4 antagonist, have improved mobilization efficacy. UCB-HSCT is equally feasible in children and adults. RIC enables HSCT to be performed in patients who are elderly or with serious medical co-morbidities. RIC-HSCT is associated with increased frequency of graft failure and disease relapse. The prophylaxis and treatment of aGVHD are still problematic.

AREAS OF CONTROVERSY

Novel strategies in PBHSC mobilization, utilization of UCB-HSCT and RIC-HSCT and prophylaxis and treatment of aGVHD, have not been critically appraised or compared with conventional strategies.

AREAS TIMELY FOR DEVELOPING RESEARCH

The safety and efficacy of novel mobilization agents have to be tested in normal allogeneic donors. Methods of increasing the cell dose or efficacy of UCB should be developed, to extend its use to adults. RIC-HSCT should be compared with conventional HSCT in young patients. Continuous efforts in defining the best prophylaxis and treatment of aGVHD should be made.

Umbilical cord stem cell transplantation

OBJECTIVES

To discuss the history, current state, and future directions of umbilical cord blood (UCB) transplantation as it relates to the emerging field of cellular therapies.

DATA SOURCES

Research studies, articles, and personal experiences.

CONCLUSION

Transplantation using hematopoietic stem cells from UCB is a life-saving option for patients with select oncologic and immunologic diseases, bone marrow failure, hemoglobinopathies, and inborn errors of metabolism.