Efficacy of inactivated SARS-CoV-2 vaccination in pediatric hematology/oncology patients:a real-world study

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has been spreading globally since its initial outbreak in 2019.Substantial evidence has revealed that children who are receiving antitumor therapy or hematopoietic stem cell transplantation(HSCT)present higher rates of severe illness and mortality[1].It is important to identify infected children with hematology and oncology diseases who have the tendency to develop worse outcomes of coronal virus disease 2019(COVID-19)during the early stage of COVID-19.Recent studies have demonstrated that vaccination against SARS-CoV-2 in adults can reduce the likelihood of infection and reduce the severity and mortality of COVID-19 when SARS-CoV-2 breakthrough infection occurs[2,3,4].However,the effectiveness of SARS-CoV-2 vaccination in children with hematology and oncology diseases is poorly defined due to the lack of relevant data,which might lead to vaccine hesitancy[5,6].

Dilemmas in diagnosis and management of hemophagocytic lymphohistiocytosis in children

Background Hemophagocytic lymphohistiocytosis(HLH)is a life-threatening entity which is characterized by severe hyperinflammation.Now the HLH-2004 protocol has been widely accepted and clinically used;however,many questions still remain in clinical practice.In this review,we discuss the dilemmas in the diagnosis and treatment of HLH in children.Data sources Original research for articles and literature reviews published in PubMed was carried out using the key term“hemophagocytic lymphohistiocytosis”.Results As the gene sequencing technology progresses,the range of causal mutations and primary HLH has been redefined.The monoallelic variants may contribute to the pathogenesis of the disease.Many conditions without defective cytotoxicity of T or NK cells may lead to HLH,such as primary immunodeficiency(PID)and dysregulated immune activation or proliferation(DIAP).HLH shares overlapping clinical and laboratory characteristics with severe sepsis,but usually the single values are more pronounced in HLH than sepsis.H score is another approach to help the diagnosis of secondary HLH.Specific Th1/Th2 cytokine patterns are very helpful tools to differentiate HLH(reactivation of HLH)from sepsis.Moreover,it also has been used successfully to stratify the therapy intensity.The treatment of HLH should consider underlying diseases,triggers and severity.HLH-94 is recommended for patients who need etoposide-based therapy.Conclusions Dramatic progress has been made during the past decades in understanding the pathophysiology of HLH.However,diagnosis and treatment of HLH remain with many dilemmas because of the heterogeneous nature of the disease.Better understanding new gene defects and more effective diagnostic approaches and salvage regimens are goals for the future.

Prognostic significance of cytokine receptor-like factor 2 alterations in acute lymphoblastic leukemia:a meta-analysis

Background:Cytokine receptor-like factor 2(CRLF2)has been shown to play a role in the pathogenesis of acute lymphoblastic leukemia(ALL).Studies have examined the relationship between CRLF2 alterations such as over-expression or deregulation and clinical outcome in childhood ALL,but the results are conflicting.This meta­analysis aimed to explore the association between CRLF2 alterations and survival of pediatric patients with ALL.Methods:Electronic databases updated to March 2014 were searched for relevant studies.A meta-analysis was made of twelve studies including 5945 patients to evaluate the prognostic significance of CRLF2 alterations on survival in childhood ALL.Hazards ratios(HRs)with 95%confidence intervals(CIs)were pooled across the studies using a fixed-effects model.Results:CRLF2 over-expression in childhood ALL was associated with poor prognosis in terms of relapse-free survival(RFS;HR=1.70,95%CI=1.28-2.24,P=0.000),event-free survival(EFS;HR=1.78,95%CI=1.05-3.01,R=0.032),and overall survival(OS;HR=2.28,95%CI=1.42-3.65,R=0.001).The combined data also suggested that CRLF2 deregulation in childhood ALL was correlated with poor EFS(HR=1.95,95%CI=1.46-2.61,R=0.000),RFS(HR=2.20,95%CI=1.53-3.18,P=0.000),and OS(HR=1.89,95%CI=1.24-2.87,P=0.003).Subgroup analysis on multivariate HRs showed that CRLF2 deregulation independently predicted a poor prognosis for childhood ALL.Conclusions:The present meta-analysis reveals that both CRLF2 over-expression and deregulation are associated with poor prognosis in pediatric patients with ALL.