Increased T regulatory cells and decreased Th1 pro-inflammatory cytokines correlate with culture-positive infection in febrile neutropenia childhood oncology patients

Association of mannose-binding lectin 2 (MBL2) and suppressor of cytokine signaling-1 (SOCS1) gene variants in children with febrile neutropenia

INTRODUCTION

Febrile neutropenia (FEN) was reported in patients with solid malignancies at a rate of 5-10% and in patients with hematological malignancies at a rate of 20-25%. In our study, we aimed to investigate the effects of mannose-binding lectin 2 (MBL2) (rs1800450) and suppressor of cytokine signaling-1 (SOCS1) (rs33989964) gene variants on patients with FEN.

METHODS

A total of 123 patients who applied to pediatric emergency department between December 2019-12/2020 included in the study. Thirteen patients were excluded from the study due to the inability to obtain DNA. Demographic-clinical features at initial diagnosis and genotype distributions were recorded. The control group consisted of volunteers with the same ethnicity, age and gender, no active infection, and no consanguinity.

RESULTS

CA/CA genotype of SOCS1 was found to be significantly higher in the healthy control group (p = 0.028). AB/BB genotype of MBL2 was significantly higher in FEN patients with a MASCC score of high risk, AA genotype was found to be higher in patients with low risk (p = 0.001). While the rate of microbiologically documented infection (MDI) was significantly lower in patients with the AA genotype of MBL2, it was significantly higher in patients with AA/BB genotypes (p = 0.025). MDI rate in patients with the del/del genotype of SOCS1 was found to be significantly lower than in patients with CA/CA + CA/del genotypes (p = 0.026).

CONCLUSIONS

In this study, it was revealed that low expression-related MBL2 genotypes were riskier for FEN and also, gene variants associated with high SOCS1 transcription were both protective against FEN and increased the rate of culture-negativity.

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.

Biomarkers in pediatric sepsis: a review of recent literature

Sepsis remains the leading cause of death in infants and children worldwide. Prompt diagnosis and monitoring of infection is pivotal to guide therapy and optimize outcomes. No single biomarker has so far been identified to accurately diagnose sepsis, monitor response and predict severity. We aimed to assess existing evidence of available sepsis biomarkers, and their utility in pediatric population. C-reactive protein and procalcitonin remain the most extensively evaluated and used biomarkers. However, biomarkers related to endothelial damage, vasodilation, oxidative stress, cytokines/chemokines and cell bioproducts have also been identified, often with regard to the site of infection and etiologic pathogen; still, with controversial utility. A multi-biomarker model driven by genomic tools could establish a personalized approach in future disease management.

Circulating T-regulatory cells in PNET: a prospective study

PURPOSE

Bone marrow regulatory T-cells (Tregs) have been evaluated in patients with peripheral neuroectodermal tumor (PNET); data on peripheral blood circulating Tregs are lacking. The objective of our study was to determine baseline Tregs (both Treg frequency and absolute number) in patients with PNET and correlate with patient characteristics, and observe their change with treatment and relapse.

METHODS

Five milliliters blood was evaluated in de novo patients with PNET at diagnosis, post-neoadjuvant chemotherapy and at relapse/progression, along with nine healthy controls using flow-cytometric analysis for Treg cells (CD4+ CD25+ FoxP3+).

RESULTS

Thirty-seven patients with median age 17 years; male/female ratio 5.1:1 had significantly higher baseline absolute Tregs than controls (mean 338.95 ± 264.63/mm(3) vs. 34.83 ± 24.90/mm(3); P < 0.001). Patients with fever had a significantly higher mean Treg frequency than those without fever (11.27 ± 8.36% vs. 8.40 ± 2.58%; P = 0.014). There was significant reduction in the circulating Tregs after neoadjuvant chemotherapy (mean 339.78 ± 294.31/mm(3) vs. 82.09 ± 91.25/mm(3), P < 0.001) and rise at progression (n = 13) as compared to values post-neoadjuvant chemotherapy (mean 240.92 ± 191.90/mm(3) vs. 57.67 ± 39.01/mm(3), P = 0.012). There was no significant difference in the event-free survival (EFS) or overall survival (OS) between the high and low Treg cell groups (2-year EFS 51.6% vs. 52.1%; P = 0.689 and OS 61.3% vs. 59.2%; P = 0.891).

CONCLUSION

This study on circulating Tregs in PNET demonstrated that peripheral blood Tregs are higher in patients than healthy controls. There was significant reduction in Tregs with chemotherapy and rise at progression.

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

BACKGROUND

Fever during neutropenia (FN) is a frequent and potentially life-threatening complication of the treatment of childhood cancer. The role of biomarkers in predicting morbidity and mortality associated with FN in children has been explored with varying results. This systematic review identified, critically appraised and synthesized information on the use of biomarkers for the prediction of outcome of FN in children/young adults, updating a review of initial assessment and adding further analysis of their value at reassessment.

METHODS

This review was conducted in accordance with the Centre for Reviews and Dissemination Methods, using 3 different random effects meta-analysis models.

RESULTS

Thirty-seven studies involving over 4689 episodes of FN in children were assessed, including an additional 13 studies investigating 18 biomarkers in 1670 FN episodes since the original review. Meta-analysis was possible for admission C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 and interleukin-8 in their ability to detect significant infection. Marked heterogeneity exists, precluding clear clinical interpretation of the results. Qualitative synthesis of the role of serial biomarkers suggests their predictive ability may be more pronounced at 24 to 48 hours compared with admission. Direct comparisons of the discriminatory power of admission values of PCT and CRP showed PCT generally had a better discriminatory estimate of serious infection than CRP.

CONCLUSIONS

There remains a paucity of robust and reproducible data on the use of biomarkers in prediction of serious infection in children with FN. Available evidence suggests PCT has better discriminatory ability than CRP and that the role of serial biomarkers warrants further study.

The immunopathology of sepsis: pathogen recognition, systemic inflammation, the compensatory anti-inflammatory response, and regulatory T cells

Sepsis, the systemic inflammatory response to infection, represents the major cause of death in critically ill veterinary patients. Whereas important advances in our understanding of the pathophysiology of this syndrome have been made, much remains to be elucidated. There is general agreement on the key interaction between pathogen‐associated molecular patterns and cells of the innate immune system, and the amplification of the host response generated by pro‐inflammatory cytokines. More recently, the concept of immunoparalysis in sepsis has also been advanced, together with an increasing recognition of the interplay between regulatory T cells and the innate immune response. However, the heterogeneous nature of this syndrome and the difficulty of modeling it in vitro or in vivo has both frustrated the advancement of new therapies and emphasized the continuing importance of patient‐based clinical research in this area of human and veterinary medicine.