Elevated serum cytokine levels using cytometric bead arrays predict culture-positive infections in childhood oncology patients with febrile neutropenia

A Dynamic Approach for Early Risk Prediction of Gram-Negative Bloodstream Infection and Systemic Inflammatory Response Syndrome in Febrile Pediatric Hemato-Oncology Patients

Background: The aim of this study was to evaluate the usefulness of C-Reactive Protein (CRP), Procalcitonin (PCT), and Interleukine 6 (IL6) biomarkers in predicting the existence of high-risk episodes (HRE) during the first 24 h of fever in pediatric cancer patients. HRE were defined as the presence of Gram-negative bloodstream infections or Systemic Inflammatory Response Syndrome. Methods: The study included 103 consecutive fever episodes in 44 hemato-oncological pediatric patients, from whom samples for biomarkers were taken upon initial evaluation (CRP-1, PCT-1 and IL6-1) and then between 12 and 24 h afterward (CRP-2, PCT-2 and IL6-2). Results: An IL6-1 value higher than 164 pg/mL showed an area under the curve (AUC) of 0.890 (0.791−0.989) and OR of 48.68 (7.92−951.42, p < 0.001) to detect HRE in multivariate analysis. A PCT-1 higher than 0.32 ng/mL showed an AUC of 0.805 (0.700−0.910) and OR of 4.55 (0.90−27.84, p = 0.076). A PCT-2 higher than 0.94 ng/mL showed an AUC of 0.836 (0.725−0.947) and OR of 13.01 (1.82−149.13, p = 0.018), and an increase in CRP between the first and second sample (CRP-2vs1) higher than 291% also showed an AUC of 0.785 (0.655−0.915) and OR of 31.09 (4.87−355.33, p = 0.001). Conclusions: IL6-1, PCT-2, and CRP-2vs1 showed a strong and independent correlation with HREs in pediatric cancer patients. CRP variations over the first 24 h provide an improvement in predictive models that are especially useful if IL-6 and PCT are not available.

Biomarkers for Diagnosing Febrile Illness in Immunocompromised Children: A Systematic Review of the Literature

OBJECTIVE

This study aims to assess the performance of biomarkers used for the prediction of bacterial, viral, and fungal infection in immunocompromised children upon presentation with fever.

METHODS

We performed a literature search using PubMed and MEDLINE and In-Process & Other Non-indexed Citations databases. Cohort and case-control studies assessing biomarkers for the prediction of bacterial, viral, or fungal infection in immunocompromised children vs. conventional microbiological investigations were eligible. Studies including adult patients were eligible if pediatric data were separately assessable. Data on definitions used for infections, fever, and neutropenia and predictive values were collected. Risk of bias was assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

Fifty-two studies involving 13,939 febrile episodes in 7,059 children were included. In total, 92.2% were in cancer patients (n = 48), and 15.7% also included hematopoietic stem cell transplantation patients (n = 8). Forty-three biomarkers were investigated, of which 6 (CRP, PCT, IL-8, IL-6, IL-10, and TNFα) were significantly associated with bacterial infection at admission, studied in multiple studies, and provided predictive data. Literature on the prediction of viral and fungal infection was too limited. Eight studies compared C-reactive protein (CRP) and procalcitonin (PCT), with PCT demonstrating superiority in 5. IL-6, IL-8, and IL-10 were compared with CRP in six, four, and one study, respectively, with mixed results on diagnostic superiority. No clear superior biomarker comparing PCT vs. IL-6, IL-8, or IL-10 was identified.

DISCUSSION

There is great heterogeneity in the biomarkers studied and cutoff values and definitions used, thus complicating the analysis. Literature for immunocompromised children with non-malignant disease and for non-bacterial infection is sparse. Literature on novel diagnostics was not available. We illustrated the challenges of diagnosing fever adequately in this study population and the need for improved biomarkers and clinical decision-making tools.

Association between cytokine concentration kinetics and prolonged fever in febrile neutropenic children with bacteremia

INTRODUCTION

Although prolonged fever in patients with neutropenic fever (NF) during empirical antibiotic therapy could be caused by dysregulated immune responses, its association with cytokine concentrations has rarely been investigated. This study determined the kinetics of cytokine concentrations in pediatric patients with NF and bacteremia and evaluated the impact of cytokine concentration kinetics on prolonged fever.

METHODS

Concentrations of 13 cytokines were measured on the initial day of NF (Day 1) and 3 days (Day 4) and 7 days (Day 8) later in 10 patients with NF with bacteremia, and their kinetics was determined. The results for each cytokine concentration on each sampling day were compared for patients with fever that lasted ⩾3 days and those with fever that lasted <3 days.

RESULTS

Interleukin (IL)-6 (p < .001) and IL-10 (p = .001) concentrations were significantly higher on Day 1 than on Days 4 and 8. However, the increased IL-6 (p = 1.000) and IL-10 (p = 1.000) concentrations on Day 1 were not associated with prolonged fever (⩾3 days). For other cytokines, the concentrations measured on Days 1, 4, and 8 were similar regardless of fever duration.

CONCLUSION

Prolonged fever in patients with NF and bacteremia was not associated with a prolonged increase in a specific cytokine concentration.

Bloodstream infection in pediatric patients with febrile neutropenia induced by chemotherapy

INTRODUCTION

Febrile neutropenia (FN) is a serious complication of cancer chemotherapy. The present study aimed to identify risk factors for documented infection in pediatric patients with FN and cancer.

METHODS

This prospective cohort study included patients under 18 years from 2016 to 2018. Infection was defined according to the Centers for Disease Control and Prevention criteria.

RESULTS

A total of 172 febrile neutropenic episodes were evaluated. From univariate analysis, the risk factors were: female gender; monocyte count < 100 cell/mm³, platelets < 50,000, C-reactive protein (CRP) > 90 mg/dl and hemoglobin < 7mg/dl at the onset of an episode; two or more episodes of FN, and; fever onset; positive blood culture at the fever onset. Independent risk factors according to the multivariate analysis were: CRP at the onset of a febrile episode > 90mg/dl, fever onset and first blood culture with a positive result. The lowest probability of infection was related to first episode and to platelets > 50,000 at the onset of fever.

CONCLUSION

A CRP > 90 at the onset of a febrile episode, platelets < 50,000, second episode or more, first fever episode during hospitalization and positive first blood culture were found to be associated with a higher risk of infection and they could be useful for the establishment of risk scores for infection in neutropenic children.

Pro-inflammatory cytokine ratios determine the clinical course of febrile neutropenia in children receiving chemotherapy

Background

Febrile neutropenia is a common and serious complication during treatment of childhood cancer. Empirical broad-spectrum antibiotics are usually administered until neutrophil cell count recovery. It was the aim of this study to investigate cytokine profiles as potential biomarkers using in-vitro sepsis models to differentiate between distinct clinical courses of febrile neutropenia (FN).

Methods

We conducted an observational study in FN episodes of pediatric oncology patients. Courses of neutropenia were defined as severe in case of proven blood stream infection or clinical evidence of complicated infection. We collected blood samples at various time points from the onset of FN and stimulated ex vivo with lipopolysaccharide (LPS) and Staphylococcus epidermidis (SE) for 24 h. Twenty-seven cytokine levels were measured in the whole blood culture supernatants by a multiplex immunoassay system.

Results

Forty-seven FN episodes from 33 children were investigated. IL-8, IL-1β, and MCP-1 expression increased significantly over time. IL-8, MIP-1α, MIP-1β, MCP-1, and TNF-α showed significantly lower concentration in patients with a clinically severe course of the FN.

Conclusions

Distinct patterns of cytokine profiles seem to be able to determine infectious FN and to predict the severity of its clinical course. If these data can be verified in a multi-centre setting, this may finally lead to an individualized treatment strategy facilitating antibiotic stewardship in these patients.

Updated systematic review and meta-analysis of the predictive value of serum biomarkers in the assessment and management of fever during neutropenia in children with cancer

Routinely measurable biomarkers as predictors for adverse outcomes in febrile neutropenia could improve management through risk stratification. This systematic review assesses the predictive role of biomarkers in identifying events such as bacteraemia, clinically documented infections, microbiologically documented infection, severe sepsis requiring intensive care or high dependency care and death. This review collates 8319 episodes from 4843 patients. C-reactive protein (CRP), interleukin (IL)-6, IL-8 and procalcitonin (PCT) consistently predict bacteraemia and severe sepsis; other outcomes have highly heterogeneous results. Performance of the biomarkers at admission using different thresholds demonstrates that PCT > 0.5 ng/mL offers the best compromise between sensitivity and specificity: sensitivity 0.67 (confidence interval [CI] 0.53-0.79) specificity 0.73 (CI 0.66-0.77). Seventeen studies describe the use of serial biomarkers, with PCT having the greatest discriminatory role. Biomarkers, potentially with serial measurements, may predict adverse outcomes in paediatric febrile neutropenia and their role in risk stratification is promising.

Cytokine serum levels during post-transplant adverse events in 61 pediatric patients after hematopoietic stem cell transplantation

Background

Veno-occlusive disease, Graft-versus-Host disease, invasive or localized bacterial, viral and fungal infections are known as adverse events after hematopoietic stem cell transplantation representing the major cause for morbidity and mortality. Detection and differentiation of these adverse events are based on clinical symptoms and routine measurements of laboratory parameters.

Methods

To identify the role of cytokines as a possible complication-marker for adverse events, 61 consecutive pediatric patients with a median age of 7.0 years who underwent hematopoietic stem cell transplantation were enrolled in this single-center retrospective study. Interleukin-1 beta (IL-1β), soluble interleukin-2 receptor (sIL-2R), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10) and tumor necrosis factor-α serum (TNF-α) levels were regularly assessed after transplantation and during transplantation related adverse events.

Results

Veno-occlusive disease was accompanied by a significant increase in levels of IL-6, IL-8 and TNF-α.Graft-versus-Host disease was associated with a significant increase of IL-10, sIL-2R, IL-6 and TNF-α, depending on the respective stage or grade. Cytokine IL-6 enabled a significant differentiation between sepsis and fungemia, sepsis and viremia, and sepsis and bacteremia. Moreover, cytokine IL-8 enabled a significant differentiation between sepsis and viremia, sepsis and bacteremia, and bacteremia and viremia whereas IL-10 made a distinction between sepsis and viremia possible.

Conclusion

The data demonstrate that proinflammatory cytokines might be putative indicators for early detection and differentiation of post-transplant adverse events and may allow prompt and adequate clinical intervention. Prospective clinical trials are needed to evaluate these findings.

Febrile neutropenia in children treated for malignancy

Febrile neutropenia (FN) in children treated for malignancy is a common and direct sequela of chemotherapy. Episodes of FN can be life-threatening, and demand prompt recognition, assessment and treatment with broad spectrum antibiotics. While in the majority of episodes no causal infection is identified, 10-20% are secondary to a bloodstream infection (BSI). A reduction in episodes of BSI could be achieved through robust infection prevention strategies, such as CVL care bundles. Alongside good antimicrobial stewardship, these strategies could reduce the risk of emergent, multi-drug resistant (MDR) infections. Emerging bacterial pathogens in BSI include Viridans Group Streptococci (VGS) and Enterobacteriaceae such as Klebsiella spp. which are known for their ability to carry MDR genes. There is also increased recognition of the role of invasive fungal infection (IFI) in FN, in particular with Aspergillus spp. Novel diagnostics, including multiplex blood and respiratory polymerase chain reaction assays can identify infections early in FN, facilitating targeted therapy, and reducing unnecessary antimicrobial exposure. Given appropriate, and sensitive rapid diagnostics, potential also exists to safely inform the risk assessment of patients with FN, identifying those at low risk of complication, who could be treated in the out-patient setting. Several clinical decision rules (CDR) have now been developed and validated in defined populations, for the risk assessment of children being treated for cancer. Future research is needed to develop a universal CDR to improve the management of children with FN.

IL-8 predicts pediatric oncology patients with febrile neutropenia at low risk for bacteremia

INTRODUCTION

Despite a low bacteremia rate, pediatric oncology patients are frequently admitted for febrile neutropenia. A pediatric risk prediction model with high sensitivity to identify patients at low risk for bacteremia is not available. We performed a single-institution prospective cohort study of pediatric oncology patients with febrile neutropenia to create a risk prediction model using clinical factors, respiratory viral infection, and cytokine expression.

MATERIALS AND METHODS

Pediatric oncology patients with febrile neutropenia were enrolled between March 30, 2010 and April 1, 2011 and managed per institutional protocol. Blood samples for C-reactive protein and cytokine expression and nasopharyngeal swabs for respiratory viral testing were obtained. Medical records were reviewed for clinical data. Statistical analysis utilized mixed multiple logistic regression modeling.

RESULTS

During the 12-month period, 195 febrile neutropenia episodes were enrolled. There were 24 (12%) episodes of bacteremia. Univariate analysis revealed several factors predictive for bacteremia, and interleukin (IL)-8 was the most predictive variable in the multivariate stepwise logistic regression. Low serum IL-8 predicted patients at low risk for bacteremia with a sensitivity of 0.9 and negative predictive value of 0.98.

CONCLUSIONS

IL-8 is a highly sensitive predictor for patients at low risk for bacteremia. IL-8 should be utilized in a multi-institution prospective trial to assign risk stratification to pediatric patients admitted with febrile neutropenia.