Differential risk of severe infection in febrile neutropenia among children with blood cancer or solid tumor

Antimicrobial resistance in patients with haematological malignancies: a scoping review

Antimicrobial resistance (AMR) is a substantial global health threat. Patients with haematological malignancies have an increased risk of AMR infection due to disease-related and treatment-related immunosuppression. This scoping review searched four bibliographic databases from Jan 1, 2000, to Dec 7, 2023, for publications on AMR bacterial infections in patients with haematological malignancies and identified 274 eligible articles. AMR prevalence data extraction focused on WHO bacterial priority pathogens. The prevalence of AMR bacterial infections from seven WHO priority pathogens in patients with haematological malignancies was 35% (95% CI 30-40; I2 99·4%). The most frequent AMR infections reported were bloodstream infections, with the highest reported AMR pathogens in third-generation cephalosporin-resistant Enterobacterales (pooled prevalence rate 44% [95% CI 23-64; I2 99·8%]), meticillin-resistant Staphylococcus aureus (43% [31-54; I2 95·9%]), and vancomycin-resistant enterococci (41% [26-56; I2 96·2%]). 53 (65%) of the 81 studies that reported mortality showed higher mortality rates associated with AMR infections. 168 (61%) studies were conducted in high-income countries, with no studies published from the WHO Africa region, revealing a substantial data gap from low-income and middle-income regions. Future efforts should prioritise standardised reporting measures, robust surveillance, antimicrobial stewardship, and well designed clinical trials, particularly in under-represented regions, to mitigate the effect of AMR on cancer care.

Outpatient Management of Fever and Neutropenia in Low-risk Children with Solid Tumors: A Quality Improvement Initiative

Background

Management of febrile neutropenia in pediatric oncology usually requires inpatient parenteral antibiotics after initial evaluation, but some patients at lower risk of sepsis could be safely managed outpatient. We describe a quality improvement project to increase outpatient management of fever and neutropenia.

Methods

We designed a standardized algorithm for children with a solid tumor diagnosis and low risk for bacteremia. The aim was to achieve outpatient management for at least 80% of eligible patients within 20 months of project initiation. We used plan-do-study-act cycles to improve algorithm compliance, including optimizing medical record decision support, developing targeted educational materials and outreach, and restructuring outpatient processes to allow for close follow-up. We surveyed patients (age ≥12 y) and parents/caregivers to assess the impact of outpatient management.

Results

The initiative led to 71% (n = 34) of eligible patients being managed as outpatients. Six percent (n = 2) of patients developed bacteremia, resulting in hospital admission. Fifteen of 26 parents/caregivers and five of 11 patients approached completed the survey. For the preferred setting of febrile neutropenia management, 83% of patients preferred to be home versus 40% of parents/caregivers. No patient expressed any of the three highest ratings in the question exploring fear regarding outpatient febrile neutropenia management versus 67% of parents/caregivers.

Conclusions

Some children with a solid tumor diagnosis at low risk for bacteremia are safely managed for febrile neutropenia as outpatients. Targeted efforts to engage parents/caregivers early in this practice change are necessary for success.

Infections in Children with Cancer Admitted in an Oncology Reference Hospital: A Cross-sectional Study

Pediatric oncology patients are usually immunosuppressed due to factors such as the neoplasm and its treatment, making them more susceptible to infections. This article aims to determine the infection profile of pediatric oncology patients admitted to an oncology reference hospital in Natal, Rio Grande do Norte, Brazil. A retrospective and cross-sectional study was conducted, collecting data from patients hospitalized due to infection in a pediatric oncology unit exclusively for the Brazilian public health system, spanning from 2018 to 2021. A total of 168 episodes of infections were identified in 96 patients, resulting in 157 hospitalizations. Among the patients with infections, 62.4% had hematological malignancies, and out of these cases, 74.6% specifically had Acute Lymphoid Leukemia. The Escherichia coli (31.9%) was the most prevalent microorganism isolated from the samples. Multidrug-resistant microorganisms accounted for 52% of all identified microorganisms. Fluoroquinolones and beta-lactam were the most prevalent antibiotic classes in the analyzed antibiograms. Factors such as Sex, type of cancer, chemotherapy in the last 30 days, were found to be associated with the occurrence of infection (p < 0.05). Conducting epidemiological studies regarding infections in pediatric oncology is crucial to development of empirical protocols, and the implementation of strategies to better control future infections.

Consensus survey on the management of children with chemotherapy-induced febrile neutropenia and at low risk of severe infection

Our aim was to identify national consensus criteria for the management of children with chemotherapy-induced febrile neutropenia (FN), for evidence-based step-down treatment approaches for patients classified at low risk of severe infection. In 2018, a five-section, 38-item survey was e-mailed to all pediatric hematology and oncology units in France (n = 30). The five sections contained statements on possible consensus criteria for the (i) definition of FN, (ii) initial management of children with FN, (iii) conditions required for initiating step-down therapy in low-risk patients, (iv) management strategy for low-risk patients, and (v) antibiotic treatment on discharge. Consensus was defined by respondents' combined answers (somewhat agree and strongly agree) at 75% or more. Sixty-five physicians (participation rate: 58%), all specialists in pediatric onco-hematology, from 18 centers completed the questionnaire. A consensus was reached on 22 of the 38 statements, including the definition of FN, the criteria for step-down therapy in low-risk children, and the initial care of these patients. There was no consensus on the type and duration of antibiotic therapy on discharge. In conclusion, a consensus has been reached on the criteria for initiating evidence-based step-down treatment of children with FN and a low risk of severe infection but not for the step-down antimicrobial regimen.

High frequency of viridians group streptococci bacteremia in pediatric neuroblastoma high-risk patients during induction chemotherapy

Existing literature on febrile neutropenia (FN) has categorized patients with acute leukemia or those undergoing allogeneic stem cell transplantation (SCT) as being high risk for severe infection, bacteremia, and poor outcomes. Comprehensive studies of infection risk in pediatric high-risk neuroblastoma (NB-HR) during induction chemotherapy are limited, and mostly merged within the solid tumor (ST) group. Therefore, it is unclear whether infectious complications and outcomes for NB-HR are the same as in other ST groups. We conducted a retrospective medical record review of pediatric FN patients in a single center from March 2009 to December 2016. FN episodes were categorized into five groups based on underlying diagnosis (acute myelogenous leukemia (AML), acute lymphocytic leukemia (ALL), NB-HR during induction chemotherapy, other solid tumors, and SCT). Comparative analyses of infectious complications between patients with NB-HR and those with other types of cancer diagnoses were performed. A total of 667 FN episodes (FNEs) were identified in 230 patients. FNEs occurred in 82 episodes with NB-HR. Bloodstream infection (BSI) occurred in 145 (21.7%) of total FN episodes. The most isolated organisms were the viridians group streptococci (VGS) (25%). NB-HR patients have higher rates of VGS bacteremia (OR 0.15, 95% [CI 0.04, 0.56]) and are more likely to be admitted to the Pediatric Intensive Care Unit (PICU) compared to patients with other solid tumors (OR 0.36, 95% [CI 0.15, 0.84]). Interestingly, there is no difference in VGS rates between patients with NB-HR and those with AML despite the fact that NB-HR patients do not receive a cytosine arabinoside (AraC)-based regimen. This large neuroblastoma cohort showed that patients with NB-HR during induction chemotherapy are at higher risk for VGS bacteremia and PICU admissions compared with patients with other solid tumors. Further prospective studies are needed to investigate infection-related complications in this high-risk group and to improve morbidity and mortality.

Prediction of Multiple Clinical Complications in Cancer Patients to Ensure Hospital Preparedness and Improved Cancer Care

Reliable and rapid medical diagnosis is the cornerstone for improving the survival rate and quality of life of cancer patients. The problem of clinical decision-making pertaining to the management of patients with hematologic cancer is multifaceted and intricate due to the risk of therapy-induced myelosuppression, multiple infections, and febrile neutropenia (FN). Myelosuppression due to treatment increases the risk of sepsis and mortality in hematological cancer patients with febrile neutropenia. A high prevalence of multidrug-resistant organisms is also noted in such patients, which implies that these patients are left with limited or no-treatment options amidst severe health complications. Hence, early screening of patients for such organisms in their bodies is vital to enable hospital preparedness, curtail the spread to other weak patients in hospitals, and limit community outbreaks. Even though predictive models for sepsis and mortality exist, no model has been suggested for the prediction of multidrug-resistant organisms in hematological cancer patients with febrile neutropenia. Hence, for predicting three critical clinical complications, such as sepsis, the presence of multidrug-resistant organisms, and mortality, from the data available from medical records, we used 1166 febrile neutropenia episodes reported in 513 patients. The XGboost algorithm is suggested from 10-fold cross-validation on 6 candidate models. Other highlights are (1) a novel set of easily available features for the prediction of the aforementioned clinical complications and (2) the use of data augmentation methods and model-scoring-based hyperparameter tuning to address the problem of class disproportionality, a common challenge in medical datasets and often the reason behind poor event prediction rate of various predictive models reported so far. The proposed model depicts improved recall and AUC (area under the curve) for sepsis (recall = 98%, AUC = 0.85), multidrug-resistant organism (recall = 96%, AUC = 0.91), and mortality (recall = 86%, AUC = 0.88) prediction. Our results encourage the need to popularize artificial intelligence-based devices to support clinical decision-making.

Decision-tree derivation and external validation of a new clinical decision rule (DISCERN-FN) to predict the risk of severe infection during febrile neutropenia in children treated for cancer

BACKGROUND

In 2017, international guidelines proposed new management of febrile neutropenia in children with cancer, adapted to the risk of severe infection by clinical decision rules (CDRs). Until now, none of the proposed CDRs has performed well enough in high-income countries for use in clinical practice. Our study aimed to build and validate a new CDR (DISCERN-FN) to predict the risk of severe infection in children with febrile neutropenia.

METHODS

We did two prospective studies. First, a prospective derivation study included all episodes of febrile neutropenia in children (aged <18 years) with a cancer diagnosis and receiving treatment for it who were admitted for an episode of febrile neutropenia, excluding patients already treated with antibiotics for this episode, febrile neutropenia not induced by chemotherapy, those receiving palliative care, and those with a stem cell allograft for less than 1 year, from April 1, 2007, to Dec 31, 2011 from two paediatric cancer centres in France. We collected the children's medical history, and clinical and laboratory data, and analysed their associations with severe infection. Sipina software was used to derive the CDR as a decision tree. Second, a prospective, national, external validation study was done in 23 centres from Jan 1, 2012, to May 31, 2016. The primary outcome was severe infection, defined by bacteraemia, a positive bacterial culture from a usually sterile site, a local infection with a high potential for extension, or an invasive fungal infection. The CDR was applied a posteriori to all episodes to evaluate its sensitivity, specificity, and negative likelihood ratio.

FINDINGS

The derivation set included 539 febrile neutropenia episodes (270 episodes in patients with blood cancer [median age 7·5 years, IQR 3·7-11·2; 158 (59 %) boys and 112 (41%) girls] and 269 in patients with solid tumours [median age 6·6 years, IQR 2·9-14·2; 140 (52 %) boys and 129 (48%) girls]). Significant variables introduced into the decision tree were cancer type (solid tumour vs blood cancer), age, high-risk chemotherapy, level of fever, C-reactive protein concentration (at 24-48 h after admission), and leucocyte and platelet counts and procalcitonin (at admission and at 24-48 h after admission). For the derivation set, the CDR sensitivity was 98% (95% CI 93-100), its specificity 56% (51-61), and the negative likelihood ratio 0·04 (0·01-0·15). 1806 febrile neutropenia episodes were analysed in the validation set (mean age 8·1 years [SD 4·8], 1014 (56%) boys and 792 (44%) girls), of which 332 (18%, 95% CI 17-20) were linked with severe infection. For the validation set, the CDR had a sensitivity of 95% (95% CI 91-97), a specificity of 38% (36-41), and a negative likelihood ratio of 0·13 (0·08-0·21). Our CDR reduced the risk of severe infection to a post-test probability of 0·8% (95% CI 0·2-2·9) in the derivation set and 2·4% (1·5-3·9) in the validation set. The validation study is registered at ClinicalTrials.gov, NCT03434795.

INTERPRETATION

The use of our CDR substantially reduced the risk of severe infection after testing in both the derivation and validation groups, which suggests that this CDR would improve clinical practice enough to be introduced in appropriate settings.

FUNDING

Ligue Nationale Contre le Cancer.

Population Pharmacokinetic Study of Vancomycin in Chinese Pediatric Patients with Hematological Malignancies

STUDY OBJECTIVES

Vancomycin is a primary antibiotic for the treatment of severe infections in children with malignant hematological disease. However, precise dosing of vancomycin is difficult in children because of high interindividual variability and limited data of pharmacokinetic profiles. The present study aims to develop a population pharmacokinetic (PPK) model for vancomycin in Chinese pediatric patients with hematological malignancies.

DESIGN

This was a retrospective pharmacokinetic study.

SETTING

The setting for this study was a tertiary-care children's hospital.

PATIENTS

This study included 92 pediatric patients with hematological malignancies who received vancomycin and experienced therapeutic drug monitoring from February 2017 to December 2018.

MEASUREMENTS AND MAIN RESULTS

A PPK model was generated with a nonlinear mixed effects model. In addition, required doses to achieve target therapeutic concentrations were simulated based on the final model. A one-compartment model with first-order elimination fit the concentration data best. Actual body weight (BW) and glomerular filtration rate (GFR) were the significant influential factors on the clearance (CL) of vancomycin. The final PPK model for CL was CL (L/h) = 4.18  × GFR / 145 0.741 × BW / 25 K , K =  BW - 0.856 / BW - 0.856 + 6 . 53 - 0.856 , and the volume of distribution was 22.3 L. The model proved to be robust and reliable. Reference dosing regimens were proposed based on the final model.

CONCLUSIONS

A PPK model of vancomycin was established for Chinese pediatric patients with hematological malignancies using a nonlinear mixed effects model, which provided a reference for the clinical application of vancomycin.