Rapid simultaneous measurement of multiple cytokines in childhood oncology patients with febrile neutropenia: increased interleukin (IL)-8 or IL-5 correlates with culture-positive infection

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.

Nonantibiotic macrolides restore airway macrophage phagocytic function with potential anti-inflammatory effects in chronic lung diseases

We reported defective efferocytosis associated with cigarette smoking and/or airway inflammation in chronic lung diseases, including chronic obstructive pulmonary disease, severe asthma, and childhood bronchiectasis. We also showed defects in phagocytosis of nontypeable Haemophilus influenzae (NTHi), a common colonizer of the lower airway in these diseases. These defects could be substantially overcome with low-dose azithromycin; however, chronic use may induce bacterial resistance. The aim of the present study was therefore to investigate two novel macrolides-2'-desoxy-9-(S)-erythromycylamine (GS-459755) and azithromycin-based 2'-desoxy molecule (GS-560660)-with significantly diminished antibiotic activity against Staphylococcus aureus, Streptococcus pneumonia, Moraxella catarrhalis, and H. influenzae We tested their effects on efferocytosis, phagocytosis of NTHi, cell viability, receptors involved in recognition of apoptotic cells and/or NTHi (flow cytometry), secreted and cleaved intracellular IL-1β (cytometric bead array, immunofluorescence/confocal microscopy), and nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) using primary alveolar macrophages and THP-1 macrophages ± 10% cigarette smoke extract. Dose-response experiments showed optimal prophagocytic effects of GS-459755 and GS-560660 at concentrations of 0.5-1 µg/ml compared with our findings with azithromycin. Both macrolides significantly improved phagocytosis of apoptotic cells and NTHi (e.g., increases in efferocytosis and phagocytosis of NTHi: GS-459755, 23 and 22.5%, P = 0.043; GS-560660, 23.5 and 22%, P = 0.043, respectively). Macrophage viability remained >85% following 24 h exposure to either macrolide at concentrations up to 20 µg/ml. Secreted and intracellular-cleaved IL-1β was decreased with both macrolides with no significant changes in recognition molecules c-mer proto-oncogene tyrosine kinase; scavenger receptor class A, member 1; Toll-like receptor 2/4; or CD36. Particulate cytoplasmic immunofluorescence of NLRP3 inflammasome was also reduced significantly. We conclude that GS-459755 and GS-560660 may be useful for reducing airway inflammation in chronic lung diseases without inducing bacterial resistance.

Selected inflammatory markers in the diagnosis and monitoring of infections in children treated for hematological malignancies

Infections in children treated for hematological malignancies pose a direct threat to life and are one of the most common causes of treatment failure in this group of patients. Unequivocal diagnosis at the early stages of infection together with an appropriate and timely treatment may be often difficult due to poor manifestation and nonspecific clinical symptoms of the infection progress. Inflammatory markers make a useful diagnostic tool for this purpose. They significantly help to diagnose, monitor, stratify and predict the outcome in severe infections. This article describes selected biomarkers, both those commonly used in clinical practice, such as erythrocyte sedimentation rate, C-reactive protein, procalcitonin as well as less common like IL-6, IL-8 and moreover one promising novel marker – pentraxin 3. The authors emphasize their diagnostic value, clinical usefulness and significance in the treatment efficacy monitoring.

Do proinflammatory cytokine levels predict serious complication risk of infection in pediatric cancer patients?

Determination of risk of severe bacterial infection complication in children with cancer is important to diminish the cost of hospitalization and therapy. In this study, children with cancer (leukemia excluded) were evaluated for risk of severe infection complication, success of therapy and the relation between clinical and inflammatory parameters during neutropenic fever attacks. Children who fulfilled the criteria of neutropenic fever with cancer were enrolled in the study. During admission, together with clinical and laboratory parameters; interleukin-6, interleukin-8, soluble tumor necrosis factor receptor II, and soluble interleukin 2 reseptor ve procalcitonin levels were detected. Empirical therapy was started with piperacillin/tazobactam and relation between the inflammatory cytokine levels and therapy response parameters were evaluated. The study population included 31 children and 50 neutropenic attacks were studied. In 48% of the attacks, absolute neutrophile count was >100/mm(3) and infectious agents were shown microbiologically in 12% of the attacks. In the study group with piperacillin/tazobactam monotherapy, the success rate without modification was 58%. In the therapy modified group mean duration of fever, antibiotherapy and hospitalization were significantly longer than the group without modification. Inflammatory cytokines' levels during admission (interleukin-6, interleukin-8, soluble tumor necrosis factor reseptor II) were higher in patients with fever >3 days and in multiple regression analysis, it has been shown that they have a determinative role on fever control time. Other cytokines did not show any significant relationship with risk of severe bacterial infection complication and success of therapy.

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.

Biomarkers for risk stratification of febrile neutropenia among children with malignancy: a pilot study

BACKGROUND

Patients receiving myelosuppressive chemotherapy remain at increased risk for developing febrile neutropenia (FN). For this heterogeneous population, a biomarker based risk stratification of FN patients may be a useful clinical tool. We hypothesized that serum biomarkers during initial presentation of an FN event could be predictive of subsequent clinical outcome.

PROCEDURE

Eighty-nine FN events from 36 non-consecutive subjects were analyzed. "High-risk" FN criteria included prolonged hospitalization (≥ 7 days), admission to pediatric intensive care unit (PICU) or a microbiology confirmed bacteremia. Patients with "low risk" FN had none of the above. Biomarkers measured during the first 2 days of FN hospitalization were analyzed and correlated with respective clinical outcome.

RESULTS

Of the 89 FN events, 44 (49%) fulfilled pre-defined high-risk criteria and 45 (51%) were low-risk. Procalcitonin level (>0.11 ng/ml) was found to be associated with the high-risk FN outcome with sensitivity of 97%. With an increase in log scale by 1, the odds of being high-risk FN increased twofold. Hs-CRP >100 mg/L had sensitivity of 88% in predicting high-risk FN. The odds of a high-risk FN event increased by approximately 1.8-fold with an increase in the log scale of hs-CRP by 1 (10-fold). In univariate analysis, IL-6, IL-8, and IL-10 were statistically significant and associated with high-risk FN. However, no statistically significant difference was found for IL-1α, sIL-2Ra, IL-3, or TNF-α.

CONCLUSIONS

Biomarkers with appropriate critical threshold values may be a useful clinical tool for appropriate risk stratification of children with FN.

Predictive value of interleukin-5 and monocyte chemotactic protein-1 for bacteremia in children with febrile neutropenia

A variety of clinical and laboratory parameters have been used to predict bacteremia. We hypothesize that the generation of a cytokine profile could be used to identify patients at higher risk of bacteremia at the time of presentation with febrile neutropenia. We prospectively evaluated children with cancer who presented with an episode of febrile neutropenia. A multiplexed flow cytometric assay was performed which measured 15 cytokines and chemokines obtained before the initiation of antibiotics. Fifty-eight episodes of chemotherapy-induced febrile neutropenia were included in this study during which 4 patients (7%) had bacteremia. An interleukin-5 level of >8 pg/dL had a sensitivity of 67% and a specificity of 96% to predict bacteremia. An monocyte chemotactic protein-1 level >1650 pg/dL had a sensitivity of 80% and a specificity of 82% to predict bacteremia. Erythrocyte sedimentation rate, C-reactive protein, protein C, and other cytokines/chemokines were not predictive of bacteremia. Elevations of interleukin-5 and monocyte chemotactic protein-1 are predictive of bacteremia in children with cancer who have febrile neutropenia. Prospective studies should be undertaken to determine whether these parameters retain predictive value in a larger series of patients and can select children for outpatient management or early discharge.

Th1/Th2 cytokine profiles in G+/G- bacteremia in pediatric hematology/oncology patients

BACKGROUND

Early diagnosis of infection and appropriate choice of antibiotics are essential not only to improve the prognosis of the patients but also to prevent from the abuse of the antibiotics in hematology/oncology children at the time of neutropenia after intensive chemotherapy.

PROCEDURE

We evaluated the quantification of Th1/Th2 cytokines with flow cytometry bead assay (CBA) in 145 hospitalized febrile hematology/oncology children with positive blood culture to seek for a rapid diagnostic method to determine the type of infection.

RESULTS

IL-4, IL-6, IL-10, TNF-α, and IFN-γ levels from both G- and G+ bacteremia groups were significantly higher than those of controls (P < 0.001). The median levels of IL-6, IL-10, TNF-α of Group G- were 525.4, 96.0, and 6.9 pg/ml, respectively, significantly higher than those of Group G+ (150.0, 22.6, and 4.5 pg/ml, respectively, P < 0.001). According to the different degrees of increased IL-6 and IL-10 levels, we named the G- bacterial infection related cytokine profile G- BIRCP and the G+ BIRCP. The specificity and sensitivity of BIRCP prediction for G- and G+ bacteria cultures were 60.2% and 75.4%, 66.8% and 70.1%, respectively. Similar therapeutic efficacy was achieved between BIRCP-based and broad-spectrum antibiotics groups (86.1% vs. 89.3%, P > 0.05), which was significantly increased as compared with that (65.5%, P < 0.05) of empirical group.

CONCLUSIONS

These results showed the promising use of the IL-6/IL-10/TNF-α determination with CBA technology for the early and rapid diagnosis, evaluation of G+/G- bacteremia in pediatric hematology/oncology patients.

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

Neutropenic patients with bacteraemia need prolonged intravenous antibiotic treatment. Using cytometric bead array technology, we show in children with febrile neutropenia that bacteraemia is associated with an elevation of at least 1 of 3 plasma cytokines plus C-reactive protein. The combination of interleukin (IL)-8, IL-6, IL-10, and C-reactive protein values above operator-defined cutoff levels identified 15 of 16 episodes of bacteraemia, making this a potentially useful technique in identifying high-risk patients who should not be discharged early from hospital. Furthermore, low risk of bacteraemia may be predicted by a combination of below threshold cytokines and negative clinical examination.

Cigarette smoke-induced changes to alveolar macrophage phenotype and function are improved by treatment with procysteine

Defective efferocytosis may perpetuate inflammation in smokers with or without chronic obstructive pulmonary disease (COPD). Macrophages may phenotypically polarize to classically activated M1 (proinflammatory; regulation of antigen presentation) or alternatively activated M2 (poor antigen presentation; improved efferocytosis) markers. In bronchoalveolar lavage (BAL)-derived macrophages from control subjects and smoker/ex-smoker COPD subjects, we investigated M1 markers (antigen-presenting major histocompatibility complex [MHC] Classes I and II), complement receptors (CRs), the high-affinity Fc receptor involved with immunoglobulin binding for phagocytosis (Fc-gamma receptor, FcγR1), M2 markers (dendritic cell-specific intercellular adhesion molecule-grabbing nonintegrin [DC-SIGN] and arginase), and macrophage function (efferocytosis and proinflammatory cytokine production in response to LPS). The availability of glutathione (GSH) in BAL was assessed, because GSH is essential for both M1 function and efferocytosis. We used a murine model to investigate macrophage phenotype/function further in response to cigarette smoke. In lung tissue (disaggregated) and BAL, we investigated CRs, the available GSH, arginase, and efferocytosis. We further investigated the therapeutic effects of an oral administration of a GSH precursor, cysteine l-2-oxothiazolidine-4-carboxylic acid (procysteine). Significantly decreased efferocytosis, available GSH, and M1 antigen-presenting molecules were evident in both COPD groups, with increased DC-SIGN and production of proinflammatory cytokines. Increased CR-3 was evident in the current-smoker COPD group. In smoke-exposed mice, we found decreased efferocytosis (BAL and tissue) and available GSH, and increased arginase, CR-3, and CR-4. Treatment with procysteine significantly increased GSH, efferocytosis (BAL: control group, 26.2%; smoke-exposed group, 17.66%; procysteine + smoke-exposed group, 27.8%; tissue: control group, 35.9%; smoke-exposed group, 21.6%; procysteine + smoke-exposed group, 34.5%), and decreased CR-4 in lung tissue. Macrophages in COPD are of a mixed phenotype and function. The increased efferocytosis and availability of GSH in response to procysteine indicates that this treatment may be useful as adjunct therapy for improving macrophage function in COPD and in susceptible smokers.

Febrile neutropenia

This review summarizes the current status and diagnostic-therapeutic challenges in febrile neutropenia. Patients with neutropenia-associated infections have a poor prognosis. A large meta-analysis of trials assessing prophylactic antibiotics has shown significant survival benefits; clinical significance of resistance is unclear. Administering broad-spectrum antibiotics to established febrile neutropenic patients has become selective, vancomycin is withheld unless absolutely necessary, and low-risk patients are identified with biological markers. Such patients are now managed with oral antibiotics at home or even without antibiotics. Protracted prolonged neutropenia is the setting par excellence for invasive fungal infections. Conventional amphotericin B administered to such risk patients reduces the incidence of fungal infections. New antifungal drugs have heightened efficacy and lowered toxicity. Novel antifungal diagnostic tests include imaging, particularly the CT "halo" sign (aspergillosis), and serology (glucan, galactomannan), and provide earlier diagnosis and treatment and better outcomes. Negative tests may indicate withholding antifungal therapy. High intermittent dosing of liposomal amphotericin B seems as safe and as effective as standard dosing regimens, but at half the drug acquisition cost. The use of nonantibiotic agents has offered alternative management strategies. Recombinant interleukin-11 reduces bacteremia, through a cytoprotective mechanism on the gut. rhIL-11 releases C-reactive protein and causes shedding of soluble TNF receptor-1, modulating the immunological milieu and the systemic inflammatory response. Other candidate molecules include RANTES and long-pentraxin 3. Recombinant growth factors reduce febrile episodes, permitting completion of chemotherapy, increase overall survival, and minimize infection mortality.

Early diagnostic and prognostic significance of a specific Th1/Th2 cytokine pattern in children with haemophagocytic syndrome

The haemophagocytic syndrome (HPS) is a rare but frequently fatal disorder of immune regulation caused by hypercytokinemia. Using cytometric bead array technique, the serum T-helper cell type 1 (Th1) and 2 (Th2) cytokines including interferon-gamma (IFN-gamma), tumour necrosis factor (TNF), interleukin (IL)-10, IL-6, IL-4 and IL-2 were determined in 24 children with de novo HPS and 87 children as control. The median levels of serum IFN-gamma, IL-10 and IL-6 in the acute phase of HPS were 901.7, 879.0 and 63.8 pg/ml, respectively, significantly higher than those after remission, and in the healthy volunteers and patients with viral infection. IL-4 was slightly elevated while IL-2 and TNF were within normal range in acute phase. Patients with bacterial sepsis showed an extremely high level of IL-6 and moderate level of IL-10, whereas IFN-gamma was only slightly elevated. Five patients were diagnosed with HPS according to the Th1/Th2 cytokine pattern 3-13 d earlier than they fulfilled the relevant diagnostic criteria. IL-10 level >2000 pg/ml was an unfavorable prognostic factor for HPS treatment response (P = 0.033) and outcome (P = 0.009). We conclude that the significant increase of IFN-gamma and IL-10 and a slightly increased level of IL-6 is an early, specific and prognostic cytokine pattern for childhood HPS.

Performance of Interleukin-6 and Interleukin-8 serum levels in pediatric oncology patients with neutropenia and fever for the assessment of low-risk

Background

Patients with chemotherapy-related neutropenia and fever are usually hospitalized and treated on empirical intravenous broad-spectrum antibiotic regimens. Early diagnosis of sepsis in children with febrile neutropenia remains difficult due to non-specific clinical and laboratory signs of infection. We aimed to analyze whether IL-6 and IL-8 could define a group of patients at low risk of septicemia.

Methods

A prospective study was performed to assess the potential value of IL-6, IL-8 and C-reactive protein serum levels to predict severe bacterial infection or bacteremia in febrile neutropenic children with cancer during chemotherapy. Statistical test used: Friedman test, Wilcoxon-Test, Kruskal-Wallis H test, Mann-Whitney U-Test and Receiver Operating Characteristics.

Results

The analysis of cytokine levels measured at the onset of fever indicated that IL-6 and IL-8 are useful to define a possible group of patients with low risk of sepsis. In predicting bacteremia or severe bacterial infection, IL-6 was the best predictor with the optimum IL-6 cut-off level of 42 pg/ml showing a high sensitivity (90%) and specificity (85%).

Conclusion

These findings may have clinical implications for risk-based antimicrobial treatment strategies.

The evolution towards ambulatory and day-case management of febrile neutropenia

Febrile neutropenia (FN) is only second to chemotherapy administration as a cause of hospital admission during treatment for cancer. As FN may signify serious or life-threatening infection, management protocols have focussed on trying to prevent adverse outcomes in these patients. However, it is now possible to identify a subset of patients with FN at low risk of life-threatening complications in whom duration of hospitalisation and intensity of therapy can be reduced safely. This review discusses how the management of FN has evolved to enable patients identified as low risk to be treated on specific low risk management strategies, with an emphasis on some of the practical considerations for the implementation of such strategies.