Validation of risk stratification for children with febrile neutropenia in a pediatric oncology unit in India

Does Fever Response to Acetaminophen Predict Bloodstream Infections in Febrile Neutropenia?

BACKGROUND

There is a need to identify clinical parameters for early and effective risk stratification and prediction of bacterial bloodstream infections (BSIs) in patients with febrile neutropenia (FN). Acetaminophen is used widely to treat fever in FN; however, little research exists on whether fever response to acetaminophen can be used as a predictor of BSIs.

OBJECTIVES

Investigate the relationship between fever response to acetaminophen and bacteremia in FN.

DESIGN/METHOD

A retrospective review of patients (1-21 years old) presenting with FN and bacteremia at Rady Children's Hospital (2012-2018) was performed. Demographic information, presenting signs/symptoms, degree of neutropenia (absolute neutrophil count (ANC) > 500 or < 500 cells/µL), absolute monocyte count, blood culture results, temperatures one, two, and six hours after acetaminophen, and timing of antibiotic administration were examined. Patients were stratified into three malignancy categories: leukemia/lymphoma, solid tumor, and hematopoietic stem cell transplant. Patients were matched with culture-negative controls based on sex, age, malignancy category, and degree of neutropenia.

RESULTS

Thirty-five case-control pairs met inclusion criteria (70 presentations of FN). The mean age of the cases was 10.7 years (± 6.3) vs. 10.0 years (± 5.9) for the controls. Twenty were female (57%). Twenty-three pairs were categorized as leukemia/lymphoma (66%), eight as solid tumors (23%), and four as HSCT (11%). Thirty-four pairs (97%) had a presenting ANC < 500 cells/µL. Higher temperature one-hour post-acetaminophen was associated with bacteremia (p = 0.04). Logistic regression demonstrated that temperature one-hour post-acetaminophen had a significant predictive value for bacteremia (p = 0.011). The area under the receiver operating characteristic curves for logistic regression and classification and regression tree analysis were 0.70 and 0.71, respectively.

CONCLUSION

While temperature one-hour post-acetaminophen was higher among patients with bacteremia and was a significant predictor of bacteremia, fever response in isolation lacks sufficient predictive value to impact clinical decision-making. Future studies are needed to assess fever responsiveness as an adjunct to existing modalities of FN risk stratification.

Predictors of Septic Shock or Bacteremia in Children Experiencing Febrile Neutropenia Post-Chemotherapy

BACKGROUND

Febrile neutropenia (FN) is an early indicator of infection in oncology patients post-chemotherapy. We aimed to determine clinical predictors of septic shock and/or bacteremia in pediatric cancer patients experiencing FN and to create a model that classifies patients as low-risk for these outcomes.

METHODS

This is a retrospective analysis with clinical data of a cohort of pediatric oncology patients admitted during July 2015 to September 2017 with FN. One FN episode per patient was randomly selected. Statistical analyses include distribution analysis, hypothesis testing, and multivariate logistic regression to determine clinical feature association with outcomes.

RESULTS

A total of 865 episodes of FN occurred in 429 subjects. In the 404 sampled episodes that were analyzed, 20.8% experienced outcomes of septic shock and/or bacteremia. Gram-negative bacteria count for 70% of bacteremias. Features with statistically significant influence in predicting these outcomes were hematological malignancy (P < .001), cancer relapse (P = .011), platelet count (P = .004), and age (P = .023). The multivariate logistic regression model achieves AUROC = 0.66 (95% CI 0.56-0.76). The optimal classification threshold achieves sensitivity = 0.96, specificity = 0.33, PPV = 0.40, and NPV = 0.95.

CONCLUSIONS

This model, based on simple clinical variables, can be used to identify patients at low-risk of septic shock and/or bacteremia. The model's NPV of 95% satisfies the priority to avoid discharging patients at high-risk for adverse infection outcomes. The model will require further validation on a prospective population.

Life-threatening infections during treatment for acute lymphoblastic leukemia on the Malaysia-Singapore 2003 and 2010 clinical trials: A risk prediction model

AIM

Life-threatening infections significantly impact the care of children undergoing therapy for acute lymphoblastic leukemia (ALL) who are at risk of severe sepsis due to both host and treatment factors. Our aim was to develop a life-threatening infection risk prediction model that would allow remote rapid triage of patients to reduce time to first dose of antibiotics and sepsis-related mortality.

METHODS

A retrospective analysis of 2068 fever episodes during ALL therapy was used for model building and subsequent internal validation.

RESULTS

Three hundred and seventy-seven patients were treated for ALL in two institutions with comparable critical and supportive care resources. A total of 55 patients accounted for 71 admissions to the critical care unit for sepsis that led to eight septic deaths during a 16-year study period. A retrospective analysis of risk factors for sepsis enabled us to build a model focused on 13 variables that discriminated admissions requiring critical care well: area under the receiver operating characteristic curve of .82; 95% CI .76-.87, p<.001, and Brier score of .033. Significant univariate predictors included neutropenia, presence of symptoms of abdominal pain, diarrhea, fever during induction or steroid-based phases, and the lack of any localizing source of infection at time of presentation.

CONCLUSION

We have developed a risk prediction model that can reliably identify ALL patients undergoing treatment who are at a higher risk of life-threatening sepsis. Clinical applicability can potentially be extended to low-middle income settings, and its utility should be further studied in real-world settings.

Procalcitonin and Interleukin-10 May Assist in Early Prediction of Bacteraemia in Children With Cancer and Febrile Neutropenia

Objectives

Febrile neutropenia (FN) causes treatment disruption and unplanned hospitalization in children with cancer. Serum biomarkers are infrequently used to stratify these patients into high or low risk for serious infection. This study investigated plasma abundance of cytokines in children with FN and their ability to predict bacteraemia.

Methods

Thirty-three plasma cytokines, C-reactive protein (CRP) and procalcitonin (PCT) were measured using ELISA assays in samples taken at FN presentation (n = 79) and within 8–24 h (Day 2; n = 31). Optimal thresholds for prediction of bacteraemia were identified and the predictive ability of biomarkers in addition to routinely available clinical variables was assessed.

Results

The median age of included FN episodes was 6.0 years and eight (10%) had a bacteraemia. On presentation, elevated PCT, IL-10 and Mip1-beta were significantly associated with bacteraemia, while CRP, IL-6 and IL-8 were not. The combination of PCT (≥0.425 ng/ml) and IL-10 (≥4.37 pg/ml) had a sensitivity of 100% (95% CI 68.8–100%) and specificity of 89% (95% CI 80.0–95.0%) for prediction of bacteraemia, correctly identifying all eight bacteraemia episodes and classifying 16 FN episodes as high-risk. There was limited additive benefit of incorporating clinical variables to this model. On Day 2, there was an 11-fold increase in PCT in episodes with a bacteraemia which was significantly higher than that observed in the non-bacteraemia episodes.

Conclusion

Elevated PCT and IL-10 accurately identified all bacteraemia episodes in our FN cohort and may enhance the early risk stratification process in this population. Prospective validation and implementation is required to determine the impact on health service utilisation.

Comprehensive Care Improvement for Oncologic Fever and Neutropenia from a Pediatric Emergency Department

Introduction

Rapid time to antibiotics (TTA) for pediatric patients with fever and neutropenia in an emergency department decreases in-hospital mortality. Additionally, national guidelines recommend outpatient antibiotic management strategies for low-risk fever and neutropenia (LRFN). This study had two specific aims: (1) improve the percent of patients with suspected fever and neutropenia who receive antibiotics within 60 minutes of arrival from 55% to 90%, and (2) develop and operationalize a process for outpatient management of LRFN patients by October 2018.

Methods

Using Lean methodologies, we implemented Plan-Do-Check-Act cycles focused on guideline development, electronic medical record reminders, order-set development, and a LRFN pathway as root causes for improvements. We used statistical process control charts to assess results.

Results

The project conducted from July 2016 to October 2018 showed special cause improvement in December 2016 on a G-chart. Monthly Xbar-chart showed improvement in average TTA from 68.5 minutes to 42.5 minutes. A P-chart showed improvement in patients receiving antibiotics within 60 minutes, from 55% to 86.4%. A LRFN guideline and workflow was developed and implemented in October 2017.

Conclusions

Implementation of guidelines, electronic medical record reminders, and order sets are useful tools to improve TTA for suspected fever and neutropenia. Utilizing more sensitive statistical process control charts early in projects with fewer patients can help recognize and guide process improvement. The development of workflows for outpatient management of LRFN may be possible, though it requires further study.

Predictive Factors of Severe Adverse Events in Pediatric Oncologic Patients with Febrile Neutropenia

OBJECTIVES

Febrile neutropenia (FN) is severe and potentially life-threatening in oncologic patients. The objective of this study is to define the factors associated with severe adverse outcomes of pediatric FN.

METHODS

A retrospective and prospective descriptive study performed in pediatric patients diagnosed with FN at King Chulalongkorn Memorial Hospital from January 2013 to December 2017. Severe adverse events defined as the presence in one of these following oxygen therapies, mechanical ventilator, shock, admission to ICU, renal dysfunction, and liver dysfunction.

RESULTS

The study included 267 patients with 563 febrile neutropenia episodes. The median (range) age was 5.1 years (1 month-15 year). Among 563 febrile neutropenia episodes, 115 episodes (20%) developed severe adverse events. The FN patients were classified into low and high-risk groups, 91% of patients with severe adverse events and all 21 patients who died were in high risk group. The overall mortality rate was 3.1%. Factors associated with severe adverse events were fungal infection (aOR 6.51, 95%CI 2.29-18.56), central venous catheter insertion (aOR 4.28, 95% CI 2.51-7.29), CPG defined high risk (aOR 3.35, 95%CI 1.56-7.17), viral infection (aOR 2.72, 95%CI 1.05-7.06), lower respiratory tract infection (aOR 2.52, 95%CI 1.09-5.82) and treatment not according to CPG (aOR 2.47, 95% CI 1.51-4.03).

CONCLUSIONS

Fungal and viral infection, central venous catheter insertion, lower respiratory tract infection, CPG defined high risk and treatment not according to CPG were associated factors of increased risk for severe adverse events. Our current institutional CPG for FN in children was applicable and improved clinical outcomes for this group of patients. <br />.

Outcomes of Febrile Neutropenia in Children With Cancer Managed on an Outpatient Basis: A Report From Tertiary Care Hospital From a Resource-limited Setting

In low-risk febrile neutropenia (FN) patients, outpatient management is now an accepted treatment, but there is a scarcity of data on high-risk patients. The aim of our study was to describe the outcome of FN treated primarily in an outpatient setting on the basis of the severity of illness at presentation, irrespective of the intensity of chemotherapy, and absolute neutrophil count. In this prospective study, not severely ill (NSI) patients were treated with empiric antibiotics at the daycare center (outpatient) and were admitted subsequently if there was persistent fever or any complication arose. Severely ill (SI) children were admitted to the hospital upfront. A total of 118 FN episodes among children with cancer on chemotherapy 18 years of age and younger were studied. Among NSI patients managed as outpatients (n=103), 89 patients (86%) recovered with outpatient treatment, and 14 patients required hospitalization after the median duration of 5 days (interquartile range: 4 to 6 d) of antibiotic therapy. The main indication for hospital admission in the SI group was hypotension (n=5), and in the NSI group, it was persistent fever (n=11). Overall, 5% of patients (6/118) died, and 2 of these were in the NSI group. The results of this study suggest that carefully selected NSI patients could be successfully treated at outpatient management in resource-poor settings and subsequent admission if warranted.

Predictors of severe adverse outcomes in febrile neutropenia of pediatric oncology patients at a single institute in Thailand

Febrile neutropenia in pediatric oncology patients may lead to severe infection, with adverse events including septic shock or death. The aim of the study was to investigate the prevalence of severe adverse outcomes and to determine the associated risk factors. This is a retrospective cohort study of pediatric oncology patients with febrile neutropenia from October 2013 to September 2017 at Thammasat University Hospital, Thailand. Clinical assessment and time-to-event of severe outcomes were analyzed. There were 95 febrile neutropenic episodes; severe adverse outcomes were documented in 11 (11.5%), with no infection-associated mortalities. Those with severe outcomes were older, received prophylactic granulocyte-colony stimulating factor (G-CSF), and had documented infection, lower initial ANC, and central venous catheter insertion. The proportional hazard regression model revealed age ≥ 10 years (hazard ratio [HR], 5.96; p = 0.005), prophylactic G-CSF (HR, 4.52; p = 0.028), and microbiologically documented infections (HR, 12.53; p = 0.017) independently predicted severe adverse outcomes. Although severe adverse outcomes occurred in only 11.5% of our febrile neutropenic episodes, we identified a few risk factors that may help predict those at highest risk.

Re-evaluating and recalibrating predictors of bacterial infection in children with cancer and febrile neutropenia

BACKGROUND

Numerous paediatric febrile neutropenia (FN) clinical decision rules (CDRs) have been derived. Validation studies show reduced performance in external settings. We evaluated the association between variables common across published FN CDRs and bacterial infection and recalibrated existing CDRs using these data.

METHODS

Prospective data from the Australian-PICNICC study which enrolled 858 FN episodes in children with cancer were used. Variables shown to be significant predictors of infection or adverse outcome in >1 CDR were analysed using multivariable logistic regression. Recalibration included re-evaluation of beta-coefficients (logistic model) or recursive-partition analysis (tree-based models).

FINDINGS

Twenty-five unique variables were identified across 17 FN CDRs. Fourteen were included in >1 CDR and 10 were analysed in our dataset. On univariate analysis, location, temperature, hypotension, rigors, severely unwell and decreasing platelets, white cell count, neutrophil count and monocyte count were significantly associated with bacterial infection. On multivariable analysis, decreasing platelets, increasing temperature and the appearance of being clinically unwell remained significantly associated. Five rules were recalibrated. Across all rules, recalibration increased the AUC-ROC and low-risk yield as compared to non-recalibrated data. For the SPOG-adverse event CDR, recalibration also increased sensitivity and specificity and external validation showed reproducibility.

INTERPRETATION

Degree of marrow suppression (low platelets), features of inflammation (temperature) and clinical judgement (severely unwell) have been consistently shown to predict infection in children with FN. Recalibration of existing CDRs is a novel way to improve diagnostic performance of CDRs and maintain relevance over time.

FUNDING

National Health and Medical Research Council Grant (APP1104527).

Risk stratification in children with cancer and febrile neutropenia: A national, prospective, multicentre validation of nine clinical decision rules

BACKGROUND

Reduced intensity treatment of low-risk febrile neutropenia (FN) in children with cancer is safe and improves quality of life. Identifying children with low-risk FN using a validated risk stratification strategy is recommended. This study prospectively validated nine FN clinical decision rules (CDRs) designed to predict infection or adverse outcome.

METHODS

Data were collected on consecutive FN episodes in this multicentre, prospective validation study. The reproducibility and discriminatory ability of each CDR in the validation cohort was compared to the derivation dataset and details of missed outcomes were reported.

FINDINGS

There were 858 FN episodes in 462 patients from eight hospitals included. Bacteraemia occurred in 111 (12·9%) and a non-bacteraemia microbiological documented infection in 185 (21·6%). Eight CDRs exhibited reproducibility and sensitivity ranged from 64% to 96%. Rules that had >85% sensitivity in predicting outcomes classified few patients (<20%) as low risk. For three CDRs predicting a composite outcome of any bacterial or viral infection, the sensitivity and discriminatory ability improved for prediction of bacterial infection alone. Across all CDRs designed to be implemented at FN presentation, the sensitivity improved at day 2 assessment.

INTERPRETATION

While reproducibility was observed in eight out of the nine CDRs, no rule perfectly differentiated between children with FN at high or low risk of infection. This is in keeping with other validation studies and highlights the need for additional safeguards against missed infections or adverse outcomes before implementation can be considered.