Infections in pediatric patients with hematologic malignancies

Teaching-Learning Programs to Prevent and Control Infections Related to Long-Term Central Venous Access Device in Cancer Patients: A Systematic Review

OBJECTIVES

To evaluate the effectiveness of teaching-learning programs for cancer patients and/or their caregivers or family in preventing and controlling infections associated with long-term central venous access devices.

DATA SOURCES

This systematic review used the CINAHL, Cochrane Library, EMBASE, LILACS, and MEDLINE via PubMed portal, Scopus, and Web of Science. Google Scholar was used for the gray literature search. The included studies were analyzed, and the obtained data were qualitatively synthesized. The risk of bias was assessed using Cochrane tools: RoB 2 and ROBINS-I. The certainty of the evidence was evaluated using the GRADE. The review protocol was registered in PROSPERO (CRD42021267530).

CONCLUSION

The teaching-learning programs were implemented through theoretical-practical and theoretical dimensions in five and two studies, respectively. The risk of bias in the studies was low, moderate, severe, and high in one, three, two, and one of them, respectively. The certainty was very low. Teaching-learning programs on central venous access devices care for cancer patients and/or their caregivers or families could be effective in reducing infection rates.

IMPLICATIONS FOR NURSING PRACTICE

This systematic review addressed the teaching-learning programs for preventing and controlling infections associated with long-term central venous access devices. We identified that the most programs were effective in reducing the infection rates. The results may influence the clinical practice of oncology nurses, and consequently, the educational strategies and methods provided not only to these patients but for caregivers and families.

Gaps in diagnosing suspected infection in immunocompromised children with cancer: A systematic review

While the survival of children with cancer has improved over time, infection remains a major morbidity and mortality risk. We conducted a systematic literature review to determine the unmet needs in diagnosing infection in immunocompromised children with cancer. The comprehensive search strategy followed the guidelines established by the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement, and spanned multiple bibliographic databases and other public sources from January 1, 2012 to June 23, 2022. From 5188 records, 34 unique pediatric-focused studies met inclusion criteria. This review highlights the lack of published data on infectious disease testing in pediatric oncology patients, and the need for well-designed clinical impact and cost-effectiveness studies of both existing and novel diagnostic platforms. Such studies are necessary to optimize diagnostic and antimicrobial stewardship, leading to improvement in patient outcomes.

Current vaccination status and safety of children with peripheral neuroblastoma in the real-world

Background

peripheral neuroblastic tumors (pNT) have high incidence and mortality, and infants are prone to various infectious diseases. The purpose of this study is to understand the immunization status of children with pNT in the real-world and the incidence of adverse reactions after vaccination, and to evaluate the feasibility of vaccination and the influencing factors of vaccination.

Methods

Children with pNT treated in the Children's Hospital Affiliated to Zhejiang University from January 1, 2011 to December 1, 2021 were included. By referring to medical records, the vaccination history of the national immunization program (NIP) vaccines and the occurrence of adverse events following immunization(AEFI), current status and safety of immunization in children with pNT in the real-world were analyzed.

Results

Among 784 children with pNT, 394 were able to obtain the history of vaccination. The overall vaccination rate of NIP vaccines was 71.49% before chemotherapy and 37.67% after chemotherapy, and the recovery time of vaccination after treatment was 16.00 (6.00,24.00) months. Age, time of tumor diagnosis and disease classification were significantly correlated with vaccination. AEFI reported an incidence of 0.23‰.

Conclusion

The vaccination rate of children with pNT is generally low, especially the vaccination rate after chemotherapy. The vaccination safety is good, children should be encouraged to immunize.

Impact of COVID-19 Related Restrictions on Infections in Children with Cancer or after Hematopoietic SCTA

BACKGROUND

Infections are a major concern for immunocompromised children. We investigated whether non-pharmaceutical interventions (NPIs) implemented in the general population during the coronavirus disease 2019 (COVID-19) pandemic in Germany had an impact on frequency, type and severity of infections in these patients.

PATIENTS AND METHODS

We analyzed all admissions to the clinic of pediatric hematology, oncology and stem cell transplantation (SCT) with (suspected) infection or fever of unknown origin (FUO) from 2018 to 2021.

RESULTS

We compared a 27-month period before NPIs (Pre-COVID: 01/2018-03/2020; 1041 cases) with a 12-month period with underlying NPIs (COVID: 04/2020-03/2021; 420 cases). During the COVID period the number of in-patient stays with FUO or infections decreased (38,6 cases/month vs. 35,0 cases/month), the median duration of hospital stays was longer (8 d (CI95: 7-8 d) vs. 9 d (CI95: 8-10 d) P=0,02)), the mean number of antibiotics per case increased (2,1 (CI95: 2,0-2,2) vs. 2,5 (CI95: 2,3-2,7); P=0,003)) and a substantial reduction of viral respiratory and gastrointestinal infections per case was seen (0,24 vs. 0,13; P<0,001). Notably, there was no detection of respiratory syncytial virus, influenza and norovirus, between May 2020 and March 2021. Based on need of intensive care measures and further parameters we conclude that severe (bacterial) infections were not significantly reduced by NPIs.

CONCLUSIONS

Introduction of NPIs in the general population during the COVID-pandemic substantially reduced viral respiratory and gastrointestinal infections in immunocompromised patients, while severe (bacterial) infections were not prevented.

Comorbidities and mortality rate in COVID-19 patients with hematological malignancies: A systematic review and meta-analysis

INTRODUCTION

The global pandemic of coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It seems that there is an association between blood cancer and an increased risk of severe COVID-19. This study aimed to review the literature reporting the COVID-19 outcomes in patients with hematological malignancies.

MATERIAL AND METHODS

In this systematic review and meta-analysis, Pubmed, Embase, and Web of Science databases were searched using the following keywords: COVID-19, SARS-CoV-2, blood cancer, myeloma, lymphoma, and leukemia. All the published articles in English from January 1, 2019, until March 10, 2021 were collected and evaluated.

RESULTS

In total, 53 studies with 2395 patients were included based on inclusion criteria. Most of these studies took place in Spain (14.81%), followed by the USA (11.11%), China (9.26%), and the UK (9.26%). More than half of COVID-19 patients with hematological malignancy were male (56.73%). Oxygen therapy played an important role in COVID-19 treatment. Moreover, anticoagulant therapies such as enoxaparin and heparin were two great assists for these patients. Fever (74.24%), cough (67.64%), and fatigue (53.19%) were the most reported clinical manifestations. In addition, hypertension and dyslipidemia were the most common comorbidities. The mortality rate due to COVID-19 in patients with hematological malignancies was 21.34%.

CONCLUSION

This study demonstrated that hematologic cancer patients were more susceptible to a severe COVID-19 than patients without blood cancer. Thus, the management of COVID-19 in these patients requires much more attention, and their screening should perform regularly.

Therapeutics for paediatric oncological emergencies

Background

With advancements in the field of oncology, cancer survival rates have improved dramatically but modern cancer treatments also come with an increasing number of disease and treatment-associated complications. This article provides an updated narrative review on the pathophysiology, clinical presentations and latest management strategies for common paediatric oncological emergencies.

Methods

An extensive PubMed^® search of all human studies in the English literature was performed in Clinical Queries for different oncology syndromes and conditions using the following Medical Subject Headings: “tumour lysis syndrome”, “hyperleukocytosis”, “disseminated intravascular coagulation”, “superior mediastinal syndrome”, “superior vena cava syndrome”, “sepsis”, “severe inflammatory response syndrome”, “acute respiratory distress syndrome”, “posterior reversible encephalopathy syndrome” and “reversible posterior leukoencephalopathy syndrome”. Categories were limited to clinical trials and reviews for ages from birth to 18 years.

Results

The general description, presentation and management of these oncologic emergencies are systematically described. Early recognition along with prompt and proactive treatment can reduce the chances of potential complications and improve the clinical outcomes, thereby improving not only survival rates in oncology patients but also their clinical outcomes and quality of life.

Conclusions

Oncologic emergencies are associated with significant mortality and morbidity. Healthcare professionals involved with the care of oncology patients must be vigilant of these emergencies.

Vaccination coverage among paediatric onco-haematological patients: an Italian cross-sectional study

Children with onco-hematological diseases are at increased risk of infection. However, this risk can in part be controlled or reduced using currently available vaccines. Despite available evidence, in patients diagnosed with a hematological or oncological disease the vaccination schedule is often inappropriately discontinued. In this study we evaluated whether the diagnosis of an oncological or hematological disease is a determinant of noncompliance with recommended vaccinations.The study was carried out between March and April 2019. The population was composed of a convenience sample of 228 children cared for in the Pediatric Oncology Department and Pediatric Hematology Department of the Policlinico Giovanni XXIII Pediatric Hospital (Bari, Italy) from 2005 to 2015. Information on the immunization status of the patients was obtained from the Apulia regional immunization database (GIAVA). A post-diagnosis adherence score was calculated.The vaccination coverage was 87.7% for the DTaP-IPV-Hep B-Hib vaccine (3 doses), 68.7% for the pneumococcal vaccine (3 doses), 75.8% for the MMR vaccine (2 doses) and 75.1% for the varicella vaccine (2 doses). The average age at vaccination was older than that recommended by the National Vaccination Plan. A diagnosis of oncological disease and an older age at enrollment were risk factors for missing vaccinations. These results showed that the overall vaccination status of pediatric onco-hematological patients is suboptimal. Improving provider communication and establishing the hospital as the primary environment for vaccine administration may lead to better vaccination compliance in this group.

The effect of anticancer treatment on cancer patients with COVID-19: A systematic review and meta-analysis

BACKGROUND

The relationship between cancer and COVID-19 has been revealed during the pandemic. Some anticancer treatments have been reported to have negative influences on COVID-19-infected patients while other studies did not support this hypothesis.

METHODS

A literature search was conducted in WOS, PubMed, Embase, Cochrane Library, CNKI and VIP between Dec 1, 2019 and Sept 23, 2020 for studies on anticancer treatments in patients with COVID-19. Cohort studies involving over 20 patients with cancer were included. The characteristics of the patients and studies, treatment types, mortality, and other additional outcomes were extracted and pooled for synthesis. RRs and forest plots were adopted to present the results. The literature quality and publication bias were assessed using NOS and Egger's test, respectively.

RESULTS

We analyzed the data from 29 studies, with 5121 cancer patients with COVID-19 meeting the inclusion criteria. There were no significant differences in mortality between patients receiving anticancer treatment and those not (RR 1.17, 95%CI: 0.96-1.43, I2 =66%, p = 0.12). Importantly, in patients with hematological malignancies, chemotherapy could markedly increase the mortality (RR 2.68, 95% CI: 1.90-3.78, I2 =0%, p < 0.00001). In patients with solid tumors, no significant differences in mortality were observed (RR 1.16, 95% CI: 0.57-2.36, I2 =72%, p = 0.67). In addition, our analysis revealed that anticancer therapies had no effects on the ICU admission rate (RR 0.87, 95% CI: 0.70-1.09, I2 =25%, p = 0.23), the severe rate (RR 1.04, 95% CI: 0.95-1.13, I2 =31%, p = 0.42), or respiratory support rate (RR 0.92, 95% CI: 0.70-1.21, I2 =32%, p = 0.55) in COVID-19-infected patients with cancer. Notably, patients receiving surgery had a higher rate of respiratory support than those without any antitumor treatment (RR 1.87, 95%CI: 1.02-3.46, I2 =0%, p = 0.04).

CONCLUSIONS

No significant difference was seen in any anticancer treatments in the solid tumor subgroup. Chemotherapy, however, will lead to higher mortality in patients with hematological malignancies. Multicenter, prospective studies are needed to re-evaluate the results.

Epidemiology and clinical characteristics of viral infections in hospitalized children and adolescents with cancer in Lebanon

Background

Viral infections in children and adolescents with malignancy are commonly encountered and have a significant impact on morbidity and mortality. Studies and epidemiological data regarding viral infections in children with cancer in developing countries are lacking. This retrospective cohort study aims to assess the burden of viral infections in children and adolescents with cancer, by assessing prevalence, risk factors, as well as morbidity and mortality of common viruses over a period of 8 years.

Methods and findings

Medical records of cancer patients treated at the Children Cancer Center of Lebanon were reviewed and 155 participants under the age of 21 were identified with at least one documented viral infection during the period from July 2009 to November 2017. This subset included 136 participants with active malignancy and 19 participants with a history of cancer who underwent hematopoietic stem cell transplantation [HSCT] and were in remission; the latter group was analyzed separately. Information regarding participant characteristics, hospital course, and complications were obtained. Associations between viral infections and certain factors were assessed. In the cohort, 64% were male, 81% were Lebanese. In participants with active malignancy, 90% received chemotherapy in the 6 months preceding the viral infection episode, 11% received radiotherapy. 51% of participants were neutropenic at the time of viral detection, and 77% were lymphopenic. 17% experienced a bacterial co-infection, and 3 experienced a viral co-infection. Among 162 viral infection episodes, clinically diagnosed skin infections, mainly herpes simplex virus type 1 and varicella-zoster virus, were the most common [44% of cases]. These were followed by laboratory-proven systemic herpes infections: cytomegalovirus [14%] and Epstein-Barr virus [6%]. Respiratory viruses: influenza and respiratory syncytial virus, accounted for 9% and 4%, respectively, whereas rotavirus represented 11% and BK virus represented 3% of cases. Acute lymphocytic leukemia was the most prevalent neoplasia [57%]. Fever was the most common presenting symptom [55%] and febrile neutropenia was the reason for admission in 24% of cases. The mean length of stay was significantly longer in participants with cytomegalovirus infections and significantly lower in rotavirus infection. Admission to the ICU occurred in 9%, complications in 8%, and mortality in 5%. Participants with viral infections post-HSCT were noted to have a significantly longer length of hospital stay compared to non-HSCT participants, with no other significant differences in clinical course and outcome. The study was limited by its retrospective nature and by the late introduction and underuse of multiplex PCR panels, which may have led to underdiagnosis of viral infections.

Conclusions

Viral infections were prevalent in our sample of cancer patients and may have contributed to morbidity and mortality. Newly available viral diagnostics are likely to vastly increase the number and scope of detectable viral infections in this population. Prospective studies using multiplex PCR technology with systematic testing of patients will be more helpful in defining the burden of viral infections. Furthermore, efforts at antimicrobial stewardship would benefit from the identification of viral causes of infection and limit the unnecessary use of antibiotics in the pediatric cancer population.

Quality Improvement Interventions across a Network of Pediatric Hematology-Oncology Clinics

Introduction

Achieving improvement in quality among different institutions is challenging. Immunocompromised children with febrile neutropenia are at high risk of severe infection. Pediatric hematology-oncology patients frequently experience central line-associated bloodstream infections (CLABSIs) associated with implanted catheters. A network of 8 pediatric hematology-oncology clinics affiliated with St. Jude Children's Research Hospital launched 2 initiatives designed to reduce the incidence of infections and improve infection treatment.

Methods

We reviewed the timing of antibiotic administration for immunocompromised patients with a fever before and after a quality improvement intervention tailored to each affiliate clinic. We also reviewed the frequency of CLABSIs before and after implementing a central line care bundle for implanted catheters in ambulatory patients.

Results

Across the affiliate clinic network, the timing of antibiotic administration improved from the preintervention period (23% of patients received antibiotics within 60 min of registration) to 53% and 73%, in successive postintervention periods. Implementing a central line bundle for implanted catheters was associated with increased compliance and a trend toward increased time between CLABSIs.

Conclusion

We describe an approach to quality improvement utilizing a system of monitoring with annual clinical audits, development of joint quality improvement initiatives, ongoing education, and focused training of staff for effecting change that improves patient healthcare across multiple institutions.

A prospective study on the epidemiology and clinical significance of viral respiratory infections among pediatric oncology patients

Respiratory infections in oncology are both common and potentially severe. However, there is still a gap in the literature, regarding the epidemiology of viral respiratory infections in children with cancer. We prospectively enrolled 224 patients, from September 2012 to August 2015. The cohort included children with hematologic or solid malignancies receiving chemotherapy, or undergoing hemopoietic stem cell transplantation, outpatients/inpatients exhibiting signs/symptoms of febrile/afebrile upper/lower respiratory infection. Viral infection was diagnosed by detection of ≥1 viruses from a sample at time of enrollment, using the CLART^® PneumoVir kit (GENOMICA, Spain). Α detailed questionnaire including demographics and medical history was also completed. Samples were processed in batches, results were communicated as soon as they became available. Children recruited in whom no virus was detected composed the no virus detected group. Viral prevalence was 38.4% in children presenting with respiratory illness. A single virus was found in 30.4%, with RSV being the most frequent. Viral coinfections were detected in 8%. Children with viral infection were more likely to be febrile upon enrollment and to present with lower respiratory signs/symptoms. They had longer duration of illness and they were more likely to receive antibiotics/antifungals. Only 22% of children with influenza received oseltamivir. Mortality was low (2.7%), however, pediatric intensive care unit (PICU) admission and death were correlated with virus detection. In our study mortality was low and PICU admission was related to virus identification. Further research is needed to clarify whether antibiotics in virus-proven infection are of value and underline the importance of oseltamivir's timely administration in influenza.

Using Practice-Based Evidence to Improve Supportive Care Practices to Reduce Central Line–Associated Bloodstream Infections in a Pediatric Oncology Unit

Children with cancer are a subset of patients with central lines with distinct risk factors for infection including periods of prolonged neutropenia and compromised mucous membrane integrity. This article relates the implementation of principles of practice-based evidence to identify interventions in addition to best practice maintenance care bundles to reduce central line–associated bloodstream infections involving viridans group streptococci and coagulase-negative staphylococci on an inpatient pediatric oncology unit. Review of individual events combined with review of current clinical practice guided the development of structured protocols emphasizing routine oral care and general supportive cares. Key principles of the protocols emphasized a 1-2-3 mnemonic and included daily bathing, twice daily oral care, and out-of-bed activity 3 times daily. Poisson regression identified a significant main effect for time period for central line–associated bloodstream infection rates involving both viridans group streptococci and coagulase-negative staphylococci. Significant differences were present between the preintervention baseline and implementation of the supportive care protocols. Project outcomes demonstrate the added value of using principles of practice-based evidence to guide the development of interventions to improve clinical care when evidence-based sources are limited.

Vancomycin serum concentrations in pediatric oncologic/hematologic intensive care patients

BACKGROUND

Usual treatment regimens with vancomycin often fail to provide adequate serum levels in patients with severe infections.

METHODS

Retrospective analysis of vancomycin trough serum measurements. The following parameters were calculated by Bayesian analysis: vancomycin clearance, distribution volume, and peak estimated concentrations. The area under the concentration curve (AUC) (total daily dose/24 h clearance of vancomycin) was used to determine the effectiveness of treatment through the ratio of AUC/minimum inhibitory concentration (MIC) above 400, using MIC=1 μg/mL, based on isolates of Staphylococci in cultures.

RESULTS

Sixty-one vancomycin trough measurements were analyzed in 31 patients. AUC/MIC>400 was obtained in 34 out of 61 dosages (55.7%), but the mean vancomycin dose required to achieve these levels was 81 mg/kg/day. In cases where the usual doses were administered (40-60 mg/kg/day), AUC/MIC>400 was obtained in nine out of 18 dosages (50%), in 13 patients. Trough serum concentrations above 15 mg/L presented a positive predictive value of 100% and a negative predictive value of 71% for AUC/MIC>400.

CONCLUSION

Higher than usual vancomycin doses may be required to treat staphylococcal infections in children with oncologic/hematologic diseases. Since the best known predictor of efficacy is the AUC/MIC ratio, serum trough concentrations must be analyzed in conjunction with MICs of prevalent Staphylococci and pharmacokinetic tools such as Bayesian analysis.

Incidence of hospital-acquired pneumonia, bacteraemia and urinary tract infections in patients with haematological malignancies, 2004-2010: a surveillance-based study

Objective

This study charted incidence trends of hospital-acquired (HA) pneumonia, bacteraemia and urinary tract infections (UTI) in a haematology department.

Methods

Prospective surveillance of hospital-acquired infections (HAI) was undertaken in a 42-bed haematology department of a university hospital. All patients hospitalized ≥48 hours between 1^st January 2004 and 31^st December 2010 were included. Definitions of HAI were based on a standardized protocol. The incidence was the number of events per 1000 patient-days at risk; only the first HAI was counted. Multivariate Poisson regression was fitted to assess temporal trends.

Results

Among 3 355 patients (58 063 patient-days at risk) included, 1 055 (31%) had HAI. The incidence of HA pneumonia, HA bacteraemia and HA UTI was respectively 3.3, 12.0 and 2.9 per 1000 patient-days at risk. HA bacteraemia incidence increased by 11% (95% confidence interval: +6%, +15%, P<0.001) per year, independently of neutropenia, central venous catheterization (CVC) and haematological disease. The incidences of HA pneumonia and HA UTI were stable. The most frequently isolated pathogens were Aspergillus spp. (59.2%) for pneumonia, coagulase-negative Staphylococcus (44.2%) for bacteraemia and enterobacteria (60%) for UTI.

Conclusion

The incidence of bacteraemia increased, indicating that factors other than CVC exposure, including chemotherapy with its impact on the immune system, could explain this trend. Further analytic studies are needed to explore the factors that could explain this trend.

Infection profile of patients undergoing autologous bone marrow transplantation in a Brazilian institution

CONTEXT AND OBJECTIVE

Hematopoietic stem cell transplantation (HSCT) has been widely used for treating oncological and hematological diseases. Although HSCT has helped to improve patient survival, the risk of developing infection during hospitalization is an important cause of morbidity and mortality. This study aimed to analyze the infection profile during hospitalization and the associated risk factors among patients undergoing autologous HSCT at the University Hospital, Universidade Federal de Juiz de Fora.

DESIGN AND SETTING

This was a cross-sectional study on patients undergoing autologous HSCT at a public university hospital.

METHODS

Patients with febrile neutropenia between 2004 and 2009 were retrospectively evaluated regarding their infection profile and associated risk factors.

RESULTS

Infection occurred in 57.2% of 112 patients with febrile neutropenia. The main source of infection was the central venous catheter (25.9%). Infection was chiefly due to Gram-positive bacteria, although Gram-negative-related infections were more severe and caused a higher death rate. Sex, age, skin color, nutritional status and underlying disease were not associated with the development of infection. Patients with severe mucositis (Grades III and IV) had a higher infection rate (P < 0.001). Patients who developed pulmonary complications during hospitalization had higher infection rates (P = 0.002). Infection was the main cause of death (57.1%) in the study sample.

CONCLUSION

Strategies aimed at reducing infection-related mortality rates among patients undergoing autologous HSCT are necessary.

Clinical practice guidelines for children with cancer presenting with fever to the emergency room

BACKGROUND

Patients with febrile neutropenia (FN) may develop severe infection, septic shock, and death. To improve the outcome of pediatric oncology patients with suspected FN, clinical practice guidelines were developed for these patients at the emergency room (ER). The objective of the present study was to evaluate compliance of the clinical practice guidelines for children with cancer presenting with fever to the ER and adverse outcomes after using the guidelines.

METHODS

A retrospective cohort study was undertaken of children with cancer presenting with fever to the ER from January 2007 to December 2008 after the clinical guidelines were implemented. The control group was the children with cancer who presented with fever during January 2005-December 2006. Guideline compliance was evaluated by recording the time of initial clinical and laboratory assessment and door-to-antibiotic time. The adverse outcomes, including septic shock and death, were determined.

RESULTS

There were 170 febrile episodes after using the guidelines. Approximately half (49.4%) of the patients received clinical assessment and laboratory results within 60 min, whereas the antibiotics were administered within 120 min in 80%. Prevalence of septic shock and intensive care unit admission were significantly reduced compared to controls (P = 0.011 and 0.016, respectively). No infection-associated mortality was found after the implementation of the guidelines.

CONCLUSIONS

Using the clinical practice guidelines for pediatric oncology patients with fever was found to reduce the adverse outcomes and improve survival.

Antibiotic resistance is associated with longer bacteremic episodes and worse outcome in febrile neutropenic children with cancer

PURPOSE

With the increasing emergence of multiresistant pathogens, better understanding of these infections is necessary. The aim of the present study was to evaluate the risk factors associated with isolating a multiresistant organism (MRO) from a positive blood culture in pediatric cancer patients with febrile neutropenia (F&N), and to study its impact on clinical course and outcome of febrile episodes.

PATIENTS AND METHODS

The association between MRO with underlying malignancy, age, disease status, hospitalization during episode, absolute neutrophil count, absolute monocyte count, clinical foci of infection, and pathogens isolated was assessed in bacteremic pediatric cancer patients. The MRO phenotype was defined as diminished susceptibility to ≥3 of the broad spectrum antibody classes.

RESULTS

Among 239 episodes of blood stream infections (BSI), Gram-positive, and Gram-negative organisms were detected in 180 (75%), and 59(25%) episodes, respectively; with 38% of isolates showing multiresistance (n = 92). Significant risk factors (P < 0.05) for MRO were hospitalization, Gram-negative organisms, presence of clinical focus of infection, reduced ANC, prolonged duration of neutropenia, and previous intake of antibiotics. Of the episodes with prolonged duration of fever extending for more than 7 days 62% (64|93) were associated with a multiresistant phenotype, while it accompanied 72% (18|25) of the cases with an unfavorable outcome; P-value <0.001.

CONCLUSION

Isolation of MRO is more likely to be associated with a prolonged course and an unfavorable outcome. Continuous multidisciplinary surveillance of BSI is warranted to develop strategies for antimicrobial resistance control.

Prophylaxis and therapy of viral infections in pediatric patients treated for malignancy

Infections are still an important cause of mortality and morbidity in pediatric cancer patients. Most of the febrile episodes in immunocompromised patients are classified as a fever of unknown origin (FUO) while bacteria are the more frequent causes of documented infections. Viral infections are also feared during chemotherapy but less data are available on their incidence and morbidity. We reviewed the literature on incidence, morbidity, and mortality of viral infections in children undergoing chemotherapy and discussed the evidence concerning the prophylaxis and the therapy.

Bone marrow mesenchymal stem cells reduce the antitumor activity of cytokine-induced killer/natural killer cells in K562 NOD/SCID mice

Adoptive cellular immunotherapy is an important treatment to eliminate residual tumor cells after hematopoietic stem-cell transplantation. Bone marrow mesenchymal stem cells (MSC) have previously been shown to exert immunoregulation functions, including inhibition of proliferation and killing activities of T cells and natural killer (NK) cells in vitro and reduction of the graft-versus-host disease. MSC can survive in vivo for a long period of time, the influence of MSC on the antitumor activity of subsequently infused immune killer cells is not clear. The aim of this study was to investigate the influences of MSC infused via different paths and at different times on the antitumor activities of cytokine-induced killer (CIK)/NK cells derived from umbilical cord blood in K562 NOD/SCID mice. The potential interaction mechanisms of MSC and CIK/NK cells infused through different paths using different intervals in vivo were subsequently explored. The results show that the antitumor activities of CIK/NK cells was inhibited by MSC when injected via the same path (tail vein), and the suppressive effect of MSC on CIK/NK cells were less pronounced when they were injected separately through different paths. There were no effects of MSC on the antitumor activities of CIK/NK cells if the MSC and CIK/NK cells were injected with a 48-h interval. Moreover, the suppressive effect continuous, even if MSC were infused 48 h earlier than CIK/NK cells. It suggests that pre-injected MSC can reduce the antitumor activities of CIK/NK cells in vivo. The probable mechanisms are that MSC and CIK/NK cells might have a greater opportunity to meet and interact if they are injected simultaneously via the same path. The suppression of MSC on CIK/NK cells in vivo mainly takes place in the reticuloendothelial system, including the lung and the liver.

Advances and challenges in infectious diseases supportive care of patients with hematologic malignancies, hematopoietic stem cell transplantation, and severe aplastic anemia

Infectious diseases are important causes of morbidity and mortality in immunocompromised patients with hematological malignancies, severe aplastic anemia (SAA), and myelodysplasia. Major advances in infectious diseases supportive care have been critical to improving the outcome of patients suffering from these life-threatening diseases. Advances in diagnosis, treatment, and prevention of life-threatening infections have reduced morbidity and mortality, improved quality of life, and enabled the use of potentially curative chemotherapy, radiation, hematopoietic stem cell transplantation (HSCT), and immunosuppressive therapy to patients battling these devastating diseases. Despite these advances, the continued development of antimicrobial resistance, emergence of new pathogens, and the evolution of host factors present evolving challenges to the successful management of infectious complications in this expanding patient population.