BACKGROUND:Hemophagocytic lymphohistiocytosis (HLH) is a rapidly progressive and often fatal disorder. This study aimed to evaluate the stratification and treatment of pediatric Epstein-Barr virus-associated HLH (EBV-HLH) based on cytokine levels and clinical condition. METHODS:Pediatric patients newly diagnosed with EBV-HLH (n = 108) were risk stratified by cytokine and clinical criteria. Six were excluded for protocol violations. RESULTS:Among the 102 evaluable patients, 61 and 41 were classified as low and high risk and initially received dexamethasone treatment and HLH-94/04 regimens, respectively. Notably, 32.4% of children (33/102) were cured by dexamethasone monotherapy. The 12-month overall survival (OS) for the entire cohort was 86.3% (95% CI, 79.6%-93.0%), with 91.8% (95% CI, 84.9%-98.7%) and 78.0% (95% CI, 65.3%-90.7%) for patients at low and high risk, respectively (P = .037). Patients at low risk whose treatment shifted from dexamethasone to the HLH-94/04 regimen presented similar 12-month OS as those initially treated with the HLH-94/04 regimen (82.1% [95% CI, 68.0%-96.2%] vs 78.0% [95% CI, 65.3%-90.7%]; P = .589). In multivariate Cox regression model, risk group and response to initial treatment at 48-72 hours thereafter were associated with OS. CONCLUSIONS:A cytokine- and clinical-based risk stratification system, combined with dynamic response assessment, enables tailored treatment for pediatric patients with EBV-HLH.

Hematopoietic stem cell transplantation (HSCT) is an effective treatment for refractory or relapsed acute lymphoblastic leukemia (ALL). However, persistent challenges, such as post-transplant relapse and Epstein-Barr virus (EBV) reactivation, remain unresolved. The current standard prophylactic strategies are complex to implement and demonstrate inconsistent efficacy. Optimizing methods to prevent cancer recurrence and control viremia is crucial for enhancing patient outcomes. We present two novel cases of patients with B-cell ALL who developed EBV viremia following allogeneic HSCT and received blinatumomab as a relapse prophylaxis. Both cases achieved sustained EBV eradication (for more than 3 months) following a course of blinatumomab (8 µg/day × 8 days), initiated during asymptomatic viremia at 3 months post-transplant. Both patients demonstrated favorable therapeutic outcomes. Blinatumomab may represent a promising therapeutic option for managing EBV viremia and providing relapse prophylaxis in patients with B-cell ALL following allogeneic HSCT.

Interferon-gamma (IFN-γ) and C-X-C motif chemokine ligand 9 (CXCL9) have been implicated as potential biomarkers for haemophagocytic lymphohistiocytosis (HLH); however, which of the two cytokines is better for the diagnosis and monitoring of HLH has not been clarified. We systematically evaluated both markers in HLH and control cohorts. While both IFN-γ and CXCL9 showed marked elevation in HLH patients, a subset (17.0%, 9/53) exhibited normal IFN-γ levels, whereas CXCL9 demonstrated near-universal positivity (98.1%, 52/53) across HLH subtypes. In the differential diagnosis of HLH versus non-Epstein-Barr virus (EBV) infection, both biomarkers showed strong discriminatory capacity with comparable area under curve (AUC) values (IFN-γ: 0.928 vs. CXCL9: 0.948; p = 0.599). However, IFN-γ demonstrated superior diagnostic precision in distinguishing EBV-HLH from infectious mononucleosis (AUC 0.926 vs. CXCL9 0.568; p < 0.001). IFN-γ levels declined to normal levels within 7 days in 85% of treated cases versus only 35% for CXCL9. Persistent CXCL9 elevation demonstrated a robust correlation with disease reactivation. These findings advocate a complementary dual-biomarker strategy-utilizing IFN-γ and CXCL9 for diagnostic confirmation and CXCL9 for therapeutic monitoring-to optimize risk-stratified management of HLH.

Abstract Induction The prognosis of refractory/relapsed (R/R) Acute myeloid leukemia (AML) is dismal. Regimens including cladribine, cytarabine, and granulocyte-stimulating factor (CLAG) resulted in excellent outcomes with a 50-62.7% complete remission (CR) rate in R/R AML children. The addition of medications with different mechanisms to CLAG can increase the efficacy for R/R AML. Homoharringtonine (HHT) is a natural plant alkaloid derived from Cephalotaxus, and has displayed promising efficacy and tolerability in pediatric and adult newly-diagnosed and R/R AML. Accordingly, we presented data of the largest sample prospective clinical data on the efficacy and safety of HHT with CLAG (CHAG regimen) in childhood R/R AML. Methods The trial in patients aged < 18 years with R/R AML (ChiCTR2000038340) is a single-arm, multicenter, open-label study conducted in China. All patients had received CHAG regimens for salvage chemotherapies as follows: cladribine (5mg/m2/day, day 1-5), HHT (1mg/m2/day, day 1-14), cytarabine (10mg/m2, quaque 12 hora, day 1-14), granulocyte colony-stimulating factor (200ug/m2/day, day1-14) (cycle 1). Patients achieving CR after cycle 1 proceeded to subsequent allogeneic hematopoietic transplantation (allo-HSCT). Those with partial response (PR) or no response (NR) were administered a second cycle of CHAG as consolidation therapy (cycle 2) and then continued to allo-HSCT once CR obtained. For patients not eligible for HSCT, 1-3 cycles of CHAG consolidations would be administered, with efforts to initiate the HSCT process. The primary objective was to determine CR rate of cycle 1, and the second endpoints included MRD rate of cycle 1, CR and MRD rate of cycle 2, and long-term survival [overall survival (OS) and event-free survival (EFS)]. Results Between December 1, 2019, and January 10, 2025, 175 fit children with R/R AML were enrolled. All subjects who received CHAG therapy had been heavily pretreated and had received a median of 3 lines (range, 1-8) of prior therapies, of whom 93 (53.1%) patients with primary refractory and 82 (46.9%) with relapsed AML [11 (6.3%) after allo-HSCT]. Among relapsed patients, 78 (44.6%) patients were first relapse, and 4 (2.3%) were second and greater relapse. The median age was 8 years old (range, 0.5-17). Twenty-four (13.7%) patients presented with extramedullary AML at diagnosis. Twenty-one were identified with FLT3-ITD and 14 with FLT3-TKD. The most common fusion gene included RUNX1::RUNX1T1 in 40 patients (22.9%) and KMT2A-rearranged in 31 (17.7%). Complex karyotype was present in 11.4% (20/175). Patients received a median of two cycles of CHAG (range, 1-5). 75 patients (42.9%) received one cycle and 100 (57.1%) received more than one cycle, including 65 (37.1%) two and 35 (20.0%) ≥ three cycles as trial treatment. The CR rate was 77.1% (135/175), with 68.6% (120/175) attaining MRD negativity via multiparameter flow cytometry (MFC) of cycle 1, and 86.1% (87/101) and 75.2% (76/101) after cycle 2. The CR and MRD negative rate for cycle 1 were 84.6% (66/78) and 76.9% (60/78) for those in first relapse, and 74.2% (72/97) and 61.9% (60/97) for patients in second and greater relapse or with refractory disease. A total of 129 (73.7%) patients consolidated with HSCT in remission, among whom 58 proceeded to HSCT after cycle 1, 55 after cycle 2 and 16 after cycle 3. 39 patients experienced relapse during treatment, including 15 relapsed during conventional chemotherapies and 24 relapsed after allo-HSCT. With a median follow-up of 20.1 months (range, 1-66.9), the median duration of EFS and OS was not reached. The estimated 36-month OS and EFS was 67.8% (95% CI, 60.5-75.9) and 60.7% (95% CI, 53.4-69.0). Acquisition of CR and MFC-MRD negativity after cycle 1, brided to HSCT showed a significant trend toward improved OS and EFS (P < 0.05). Meanwhile, fusion gene of RUNX1-RUNX1T1, CBFB-MYH11 and KMT2Ar, and complex karyotype and previous utilization of HSCT play a statistical significance on OS and EFS (P < 0.05). The common treatment emergent ≥ grade 3 AE occurring were hematologic toxicities, with no grade 5 events and related mortality observed. The most common nonhematologic toxicities were febrile neutropenia, mostly assessed as grade 3 to 4, and not life-threatening. Conclusion In summary, this trial showed that CHAG regimen is safe and highly active in R/R AML children. The CHAG regimen may represent a highly promising bridging strategy to allo-HSCT in pediatric R/R AML.

OBJECTIVE:To screen interleukin (IL)-1β secretion-related membrane transporters by macrophage experiment in vitro and conventional knockout mice. METHODS:THP-1 cell line was differentiated to obtain human THP-1-derived macrophages, and the primary macrophages were obtained from human peripheral blood. FVB wild-type mice with the same sex and age were used as the controls of MRP1 knockout mice. The macrophages in abdominal cavity and bone marrow of mice were cultivated. The cells were treated with ABCC1/MRP1, ABCG2/BCRP, ABCB1/P-gp, OATP1B1, and MATE transporter inhibitors, then stimulated by lipopolysaccharide and adenosine triphosphate. The secretion level of IL-1β was detected by ELISA, Western blot, and immunofluorescence. RESULTS:After inhibiting ABCC1/MRP1 transporter, the secretion of IL-1β decreased significantly, while inhibition of the other 4 transporters had no effect. In animal experiment, the level of IL-1β secreted by macrophages in bone marrow of MRP1 knockout mice was significantly lower than control group (P < 0.05). CONCLUSION:ABCC1/MRP1 transporter is a newly discovered IL-1β secretion pathway, which is expected to become a new target for solving clinical problems such as cytokine release syndrome.

Abstract Background and aim Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and infectious mononucleosis (EBV-IM) share mimic symptoms in the early stages of childhood development. We aimed to examine the clinical features and laboratory indices of these two diseases in children and uncover unique indicators to assist pediatricians in identifying these diseases early. Methods We collected clinical data from 791 pediatric patients diagnosed with EBV-IM or EBV-HLH, compared the clinical traits and laboratory biomarkers presented in the two groups, and constructed predictive models based on them. Results Patients with EBV-IM had greater ratios of cervical lymphadenopathy, eyelid edema, and tonsillitis, whereas individuals with EBV-HLH were more likely to have hepatomegaly and splenomegaly. When using the criteria of interleukin (IL)-10 > 89.6 pg/mL, interferon (IFN)-γ > 45.6 pg/mL, ferritin > 429 μg/L, D-dimer > 3.15 mg/L and triglycerides > 2.1 mmol/L, the sensitivity was 87.9%, 90.7%, 98.1%, 91.1% and 81.5% to predict EBV-HLH, while the specificity was 98.4%, 96.3%, 96.5%, 94.1% and 80.6%, respectively. A logistic regression model based on four parameters (IL-10, ferritin, D-dimer, and triglycerides) was established to distinguish EBV-HLH patients from EBV-IM patients, with a sensitivity of 98.0% and a specificity of 98.2%. Conclusions IL-10, IFN-γ, ferritin and D-dimer levels are significantly different between EBV-HLH and EBV-IM. Predictive models based on clinical signs and laboratory findings provide simple tools to distinguish the two situations.

BackgroundHemophagocytic lymphohistiocytosis (HLH) is a rapidly fatal disease caused by immune dysregulation. Early initiation of treatment is imperative for saving lives. However, a laboratory approach that could be used to quickly evaluate the HLH subtype and clinical situation is lacking. Our previous studies indicated that cytokines such as interferon (IFN)-γ and interleukin (IL)-10 were helpful for the early diagnosis of HLH and were associated with disease severity. The purpose of this study is to clarify the different cytokine patterns of various subtypes of pediatric HLH and to investigate the role of cytokines in a simple evaluation of disease feature.Patients and MethodsWe enrolled 256 pediatric patients with newly diagnosed HLH. The clinical features and laboratory findings were collected and compared among different subtypes of HLH. A model integrating cytokines was established to stratify HLH patients into different clinical groups.ResultsTwenty-seven patients were diagnosed with primary HLH (pHLH), 179 with EBV-HLH, and 50 with other causes. The IL-6, IL-10, and IFN-γ levels and the ratios of IL-10 to IFN-γ were different among EBV-HLH, other infection-associated HLH, malignancy-associated HLH, familial HLH, and X-linked lymphoproliferative disease. Patients with the ratio of IL-10 to IFN-γ >1.33 and the concentration of IFN-γ ≤225 pg/ml were considered to have pHLH, with a sensitivity of 73% and a specificity of 84%. A four-quadrant model based on the two cutoff values was established to stratify the patients into different clinical situations. The HLH subtypes, cytokine levels, treatment regimens, treatment response, and outcomes were different among the four quadrants, with the 8-week mortality from 2.9 ± 2.9% to 21.4 ± 5.5% and the 5-year overall survival from 93.9 ± 4.2% to 52.6 ± 7.1%.ConclusionsDifferent subtypes of HLH present distinct cytokine patterns. IFN-γ and the ratio of IL-10 to IFN-γ are helpful tools to differentiate HLH subtypes. A four-quadrant model based on these two parameters is a useful tool for a simple evaluation of the HLH situation.

RATIONALE:Familial hemophagocytic lymphohistiocytosis (FHL) is a potentially fatal disease that rarely presents in the neonatal period. Timely diagnosis is a key challenge owing to the atypical clinical manifestations. Here, we describe a case of FHL type 3 with disease onset in the early neonatal period and review the relevant literature. Our findings may provide insights into the diagnosis and treatment of this rare disease.PATIENT CONCERNS:A 6-day-old male neonate presented with fever, hepatosplenomegaly, cytopenia, hyperferritinemia, hypofibrinogenemia, hemophagocytosis, and hypertriglyceridemia.DIAGNOSIS:Considering the clinical picture (prolonged fever, progressive hepatosplenomegaly, high triglycerides, low fibrinogen, and high ferritin), along with abnormal natural killer-cell activity, combining sequence analysis of genomic DNA results (compound heterozygous mutations of UNC13D), the patient was finally diagnosed with FHL type 3 (FHL3).INTERVENTIONS:The patient was initially treated with HLH-1994 protocol and subsequently switched to an oral regimen of ruxolitinib due to incomplete remission of the disease.OUTCOMES:The trend of change in weekly cytokine levels, neutrophil counts, hemoglobin, and platelet counts indicated that the complete remission was not achieved after the treatment of HLH-1994 protocol. The platelet counts fluctuated within the normal range after oral administration of ruxolitinib. But soon after, the patient did not respond to treatment and eventually died of respiratory failure.LESSON:Timely diagnosis of FHL is challenging. This case report illustrates that thrombocytopenia can be the first clinical sign of FHL with neonatal onset. Genetic testing, detection of cytokines, and flow cytometry should be performed as soon as possible to confirm the diagnosis. Given the high morbidity and mortality of FHL, pediatricians should have a high suspicion index for this disease.

The aim of this study is to systematically compare the performance of C-reactive protein (CRP), procalcitonin (PCT) and serum cytokines in identifying pediatric cancer patients with high-risk infection. A prospective observational study was performed from January 2014 through December 2016. Consecutive pediatric cancer patients who experienced febrile illness during hospitalization were enrolled. The CRP, PCT, interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma were determined within 6 h of fever onset. A total of 3118 episodes of febrile illness were included, with 13.1% episodes documented as bloodstream infection (BSI) and 3.5% diagnosed as septic shock. Patients with BSI presented much higher levels of PCT, IL-6, IL-10 and TNF-alpha than patients with other types of fever and have much higher incidence of septic shock (11.2% vs. 2.3%, P < 0.001). IL-6 and IL-10 showed better performance in identifying patients with gram-negative bacteremia (GNB) and septic shock than CRP and PCT, respectively. The area under the curve (AUCs) of receiver operating characteristic (ROC) curve for septic shock prediction were 0.65, 0.78, 0.89 and 0.87 for CRP, PCT, IL-6 and IL-10, respectively. Furthermore, elevation of IL-6 and IL-10 were strongly associated with the development of GNB and septic shock. Our results indicate that BSI, especially GNB, is a high-risk form of infection which results in high incidence of septic shock. IL-6 and IL-10 performance better than CRP and PCT in identifying patients with high-risk febrile illness.

Hemophagocytic lymphohistiocytosis is a rapidly progressing and fatal disease. Early identification of early death for HLH patients based on the laboratory findings at the time of diagnosis could improve the overall survival. A retrospective study was performed on 95 Chinese pediatric patients with HLH. Patients' data including clinical features and laboratory findings at diagnosis were collected. In a multivariate Cox proportional hazard regression model analysis, albumins <= 27.75 g/L (hazard ratio (HR) = 11.82, 95% confidence interval (CI) 2.58-54.23; P = 0.001), LDH >= 3707.5 U/L (HR = 4.15, 95%CI 1.43-12.01; P = 0.009), and IL-10 >= 456 pg/ml (HR = 12.39, 95%CI 1.59-96.79; P = 0.016) at diagnosis were independent prognostic factors of early death. The risk of early death was 33-fold increase in patients with three risk factors (HR = 33.33; 95%CI 8.40-125.00; P < 0.001), and 12-fold increase in patients with two risk factors (HR = 12.80; 95%CI 2.34-69.80; P = 0.002) when compared to it in patients with zero to one risk factor. Our results reveal that HLH patients with the risk of early death can be identified by laboratory findings at diagnosis, which may help guide the treatment decision making for this disease.

The ETS-related gene (ERG) has been demonstrated to be associated with overall survival in cytogenetically normal acute myeloid leukemia and acute T cell-lymphoblastic leukemia (T-ALL) in adult patients. However, there are no data available regarding the impact of ERG expression on childhood ALL. In the present study, ERG expression levels were analyzed in bone marrow samples from 119 ALL pediatric patients. ALL patients demonstrated higher ERG expression compared with the controls (P<0.0001). In addition, low ERG expression identified a group of patients with higher white blood cell counts (P=0.011), higher percentages of T-ALL immunophenotype (P=0.027), and higher relapse rates (P=0.009). Survival analyses demonstrated that low ERG expression was associated with inferior relapse-free survival (RFS) in childhood ALL (P=0.036) and was an independent prognostic factor in multivariable analyses for RFS. In conclusion, low ERG expression is associated with poor outcomes and may be used to serve as a molecular prognostic marker to identify patients with a high risk of relapse in childhood ALL.