sHLH Patients Research Articles

Effect of Plasma Epstein-Barr Virus Nucleic Acid Loads on the Clinical Features and Prognosis in Adult Secondary Hemophagocytic Lymphohistiocytosis

To investigate the effect of pre-treatment plasma Epstein-Barr virus (EBV) DNA copy number on the clinical features and prognosis of patients with adult secondary hemophagocytic lymphohistiocytosis(sHLH). The clinical characteristics, survival rate, and prognostic factors of 171 patients with adult sHLH treated at Jiangsu Province Hospital from June 2017 to January 2022 were retrospectively analyzed in this study. Patients were divided into three groups, including the EBV DNA-negative group(<5.0×102 copies/ml), lower EBV-DNA loads group(5.0×102-8.51×104 copies/ml), and higher EBV-DNA loads group(＞8.51×104 copies/ml), according to pre-treatment plasma EBV-DNA copy number. Cox regression model was established for screening prognostic factors. Adult sHLH survival prediction model was constructed and realized through the nomogram based on EBV-DNA load after adjusted the factors affecting survival of etiology and treatment strategy.Concordance index (C-index) and calibration curves were calculated to verify model predictive and discriminatory capacity. Among 171 adult sHLH patients, 84 patients were not infected with EBV (EBV DNA-negative group), and 87 with EBV (EBV DNA-positive group, 48 lower EBV-DNA loads group and 39 higher EBV-DNA loads group). Consistent elevations in the levels of liver enzymes (ALT and AST), LDH, TG, β 2-microglobulin and ferritin across the increasing of EBV-DNA load (all P <0.05), while the levels of fibrinogen decrease (P <0.001). The median follow-up time was 52 days (range 20-230 days), and 123 patients died. The overall survival (OS) rate of patients in EBV DNA-positive group was lower than that in EBV DNA-negative group (median OS: 40 days vs 118 days, P <0.001). Higher EBV-DNA loads had worse OS (median OS: 24 days vs 45 days vs 118 days, P <0.0001 for trend) compared to lower EBV-DNA loads and EBV DNA-negative group. Multivariate Cox analysis revealed that higher EBV-DNA loads (P =0.005), fibrinogen≤1.5 g/L (P ＝0.012), ferritin (P ＝0.041), associated lymphoma (P ＝0.002), and anti-tumor based strategy (P ＝0.001) were independent prognostic factors for OS. The C-indexes of 30 day, 90 days, 365 days survival rate were all greater than 0.8 of the nomogram model and calibration curves provided credibility to their predictive capability. Subgroup analysis showed that patients with higher EBV-DNA loads had a significantly worse prognosis in adult sHLH who were women, ferritin＞5 000 μg/L, β2-microglobulin＞7.4 mmol/L and regardless of age, etiologies, HScore points. The EBV-DNA load is a strong and independent predictor for survival in patients with sHLH. The prognostic nomogram based on EBV-DNA loads was dependable and provides a visual tool for evaluating the survival of adult sHLH.

CRP and sCD25 help distinguish between adult-onset Still's disease and HLH.

Adult-onset Still's disease (AOSD) and secondary hemophagocytic lymphohistiocytosis (sHLH) are both hyperferritinemic cytokine storm syndromes that can be difficult to distinguish from each other in hospitalized patients. The objective of this study was to compare the inflammatory markers ferritin, D-dimer, C-reactive protein (CRP), and soluble CD25 (sCD25) in patients with AOSD and sHLH. These four markers were chosen as they are widely available and represent different aspects of inflammatory diseases: macrophage activation (ferritin); endothelialopathy (D-dimer); interleukin-1/interleukin-6/tumour necrosis factor elevation (CRP) and T cell activation (sCD25). This was a single-center retrospective study. Patients diagnosed by the Hematology service at Vancouver General Hospital for AOSD or sHLH from 2009 to 2023 were included. There were 16 AOSD and 44 sHLH patients identified. Ferritin was lower in AOSD than HLH (median 11 360 μg/L vs. 29 020 μg/L, p = .01) while D-dimer was not significantly different (median 5310 mg/L FEU vs. 7000 mg/L FEU, p = .3). CRP was higher (median 168 mg/L vs. 71 mg/L, p <.01) and sCD25 was lower (median 2220 vs. 7280 U/mL, p = .004) in AOSD compared to HLH. The combined ROC curve using CRP >130 mg/L and sCD25< 3900 U/mL to distinguish AOSD from HLH had an area under the curve (AUC) of 0.94 (95% confidence interval 0.93-0.97) with sensitivity 91% and specificity 93%. These findings suggest that simple, widely available laboratory tests such as CRP and sCD25 can help clinicians distinguish AOSD from HLH in acutely ill adults with extreme hyperferritinemia. Larger studies examining a wider range of clinically available inflammatory biomarkers in a more diverse set of cytokine storm syndromes are warranted.

Comprehensive mapping of immune perturbations associated with secondary hemophagocytic lymphohistiocytosis.

Secondary hemophagocytic lymphohistiocytosis (sHLH) is a hyperinflammatory syndrome characterized by immune disorders. It is imperative to elucidate the immunophenotypic panorama and the interactions among these cells in patients. Human peripheral blood mononuclear cells were collected from healthy donors and sHLH patients and tested using multicolor flow cytometry. We used FlowSOM to explore and visualize the immunophenotypic characteristics of sHLH. By demonstrating the phenotypes of immune cells, we discovered that sHLH patients had significantly higher levels of CD56+ monocytes, higher levels of myeloid-derived suppressor cells, low-density neutrophil-to-T cell ratio, and higher heterogeneous T cell activation than healthy donors. However, natural killer cell cytotoxicity and function were impaired. We then assessed the correlations among 30 immune cell types and evaluated metabolic analysis. Our findings demonstrated polymorphonuclear myeloid-derived suppressor cells, CD56+ monocytes, and neutrophil-to-T cell ratio were elevated abnormally in sHLH patients, which may indicate an association with immune overactivation and inflammatory response. We are expected to confirm that they are involved in the occurrence of the disease through further in-depth research.

Association of a decreased platelet count with poor survival in patients with adult secondary hemophagocytic lymphohistiocytosis.

We aimed to examine the association between baseline platelet count (PLT) and the prognosis of adult secondary hemophagocytic lymphohistiocytosis (sHLH). Data from 292 patients with pretreatment platelet counts were retrospectively analysed from January 2016 to December 2020. We categorized platelet count into quartiles. Multivariable Cox proportional hazards models and restricted cubic splines (RCS) were used to evaluate the relationship between platelet count and mortality. During a median follow-up of 53 (interquartile ranges, 17-223) days, a total of 208 deaths occurred. After adjusting for multiple variables, a non-linear and inverse relationship was observed between platelet count and mortality in sHLH patient (P for nonlinearity=0.002). For non- lymphoma-associated haemophagocytic lymphohistiocytosis (non-LHLH), a similar curve was also observed (P for nonlinearity =0.028). Decreased PLT (PLT Q4) was associated with an increased risk of mortality (adjusted hazard ratio: 1.97; 95% confidence interval: 1.28-3.04; Ptrend =0.005). Similar results were observed in the LHLH subgroup (adjusted hazard ratio: 1.84; 95% confidence interval: 1.05-3.24; Ptrend =0.024) but not in the non-LHLH subgroup (Ptrend =0.266). Baseline platelet count demonstrated a nonlinear and inverse association with an increased risk of mortality among adult sHLH patients. This method is used to identify sHLH patients with inferior overall survival due to its low cost and universal availability.

The Identification and Characterization of Retrospective Cohorts of Secondary Hemophagocytic Lymphohistiocytosis (sHLH) Patients in the United States

Background:Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening hyperinflammatory syndrome induced by aberrantly activated myeloid and T cells. Primary or familial HLH (pHLH) is a genetic disorder that typically presents in young children. Secondary HLH (sHLH), which can occur at any age but is most common in adults, is triggered by infection, autoimmune disease, malignancy, or other conditions. Without treatment, HLH is universally fatal; even with existing etoposide-based regimens, survival remains low, particularly for malignancy-associated sHLH. There are no approved therapies specifically for sHLH, and most of our understanding of HLH diagnosis comes from studies of pHLH. The aim of this study is to assemble historical cohorts of sHLH patients from two, large US medical systems to better understand and refine the sHLH clinical definition, characterize demographic, clinical, and treatment characteristics, and compare survival and healthcare resource utilization (HRU) of the cohorts to matched comparison groups. Preliminary findings on the identification of sHLH patients at one US site were previously described [Broome et al., Blood (2022) 140 (Supplement 1): 5490-5491]. Data on sHLH patient identification at both sites are presented here. Methods: Two Electronic Medical Record (EMR) systems were queried to identify potential patients (site 1: 2009-May 2022 with no age restrictions and site 2: 2006-2022 patients &amp;gt;18 years of age). Three methods were developed for patient identification. Method 1 identified patients with any mention of an HLH-related ICD code (ICD-9 288.4; ICD-10 D76.1, D76.2, D76.3). Method 2 identified patients with combinations of an elevated ferritin value (1,000-10,000 ng/mL or &amp;gt;10,000 ng/mL) or a sCD25 test (predictive markers of malignancy-associated sHLH from the Optimized HLH Inflammatory [OHI] index). Method 3 identified patients with etoposide and dexamethasone treatment, removing patients receiving this treatment as part of a chemotherapy regimen. Full chart review of some cohorts was not logistically feasible because of their size (no ferritin &amp;gt;1,000 AND any sCD25 test, ferritin &amp;gt;10,000 AND no sCD25 test, and etoposide and dexamethasone treatment); in these instances, patient records were screened for a mention of HLH or MAS. At each site, one clinician reviewed all charts, and a second clinician reviewed a random sample. HLH diagnosis was assigned based on expert judgement, and all diagnostic conflicts were resolved between the two clinicians. Clinical and diagnostic data on sHLH patients were pulled from the EMR by the reviewing clinician. Results: 528 patients were identified at site 1 via the three methods and their charts were reviewed confirming 65 patients with sHLH. Likewise, among 714 charts reviewed at site 2, 188 patients were confirmed with sHLH. Among all patients with an ICD code (Method 1), 17% (56/327) were determined to have sHLH at site 1 and 33% (162/488) at site 2. Among patients reviewed with ferritin/sCD25 features (Method 2), 4% (9/200) were determined to have sHLH at site 1 and 11% (25/212) at site 2. Among patients reviewed with Method 3, 0% (0/1) were determined to have sHLH at site 1, and site 2 data were not available. (See Table 1) Additional analyses on clinical and treatment characteristics of the sHLH cohorts and survival/HRU comparisons will be presented. Conclusions: Since HLH is a rare, heterogeneous, and complex disease to diagnose and treat, HLH-related ICD codes may not accurately and sufficiently capture the spectrum of HLH patients in EMRs.Clinical indicators of disease were essential for identifying additional patients with this rare disorder. The general consistency of the findings between the two study sites supports the application of this patient identification algorithm across diverse medical centers.

A Phase 1b Study of ELA026, a Monoclonal Antibody Targeting Signal Regulatory Protein-α/β1/γ, in Patients with Newly Diagnosed and Previously Treated Secondary Hemophagocytic Lymphohistiocytosis

Introduction: ELA026 is under investigation in secondary hemophagocytic lymphohistiocytosis (sHLH), a life-threatening, hyperinflammatory condition that is most often triggered by malignancies, autoimmune disorders, and infectious diseases. There are no approved therapies for sHLH, and current treatment approaches, particularly for malignancy-associated HLH (mHLH), are suboptimal. For example, in adult patients with mHLH, median overall survival (mOS) is approximately 2 months (Lee et al. 2023). ELA026 is a monoclonal antibody directed against signal regulatory protein-α/β1/γ and is intended to target the activated myeloid and T cells that drive sHLH. Methods: This is an open-label, single-arm, Phase 1b global multicenter study (NCT05416307) to evaluate the safety, efficacy, pharmacokinetics, and pharmacodynamics of ELA026 in newly diagnosed and previously treated sHLH patients, aged 12 years or older (6 years or older in select countries including the US). In Cohort 1, an intra-patient dose escalation of ELA026 occurs in the absence of a dose limiting toxicity (DLT) and optimal biomarker response. Response is evaluated as described in Locatelli et al. 2020. Results: Six mHLH patients enrolled in Cohort 1 with median age of 50 years (range 21-67). Three patients were refractory to etoposide-based therapies and/or anti-cytokine therapies. No DLTs or study drug-related serious adverse events occurred. Five patients were deemed evaluable for efficacy based on &amp;gt;1 week of ELA026 exposure (efficacy assessment is pending). All 5 patients received concurrent chemotherapy for their malignancies. As of July 31, 2023, 3 patients are alive and 2 patients have died from complications of malignancy (mOS has not been reached but has exceeded 3 months). Three patients who had periods of ELA026 monotherapy displayed early, progressive monocyte and lymphocyte reductions with associated improvements in C-reactive protein and other sHLH-associated biomarkers. Updated study results and progress will be provided at the meeting. Conclusion: Preliminary data suggest ELA026 is well tolerated in sHLH patients and induces early biomarker changes that warrant further clinical investigation.

The signature and predictive value of immune parameters in patients with secondary hemophagocytic lymphohistiocytosis

BackgroundSecondary hemophagocytic lymphohistiocytosis (sHLH) is a rare but fatal clinical syndrome, characterized by severe immune dysfunction and overwhelming inflammatory response. However, the host immune signature and also its role in predicting the clinical outcome are not fully described. ObjectiveThe present study aims to investigate the host immune status of sHLH patients in the early stage of the disease, including lymphocyte subsets, phenotypes and cytokines, and also to explore its clinical value in prognosis. MethodsSixty-four patients with sHLH admitted to a tertiary hospital in central China between 2018 and 2022 were enrolled, of which 21 were deceased. The subsets and phenotypes of lymphocytes, and the levels of cytokines in serum were analyzed. ResultsIn patients with sHLH, the percentages of total T cells, CD8+ T cells, HLA-DR+ T cells, HLA-DR+CD8+ T cells, CD45RO+CD4+ T cells, and the levels of IL-1β, IL-2R, IL-6, IL-8, IL-10 and TNF-α were significantly increased, while the percentages of CD4+ T cells, NK cells, CD45RA+CD4+ T cells, CD45RA+ regulatory T (Treg) cells, the counts of total T cells, total B cells, CD4+ T cells, CD8+ T cells, NK cells, and the ratio of CD4+ T/CD8+ T cells were significantly decreased, compared with healthy controls (HC). In addition, dysregulation of host immune response and high inflammatory status were more obvious in deceased patients than that of survivors. Kaplan-Meier survival analysis and multivariate logistic regression analysis demonstrated that lower levels of CD4+ T cells count and CD28+CD4+ T cells percentage, but higher levels of NK cells percentage and IL-1β were poor prognostic indicators of sHLH. ConclusionThe evaluation of immunological markers has critical value for selecting prognostic markers and potential treatment target among adults with sHLH.

Genetic and clinical characteristics of primary hemophagocytic lymphohistiocytosis in children.

To analyze the genetic variation and prognosis of primary hemophagocytic lymphohistiocytosis (pHLH) in children and the clinical features of isolated central nervous system HLH (CNS-HLH). We retrospectively analyzed the clinical and genetic data of 480 HLH children admitted to our hospital from September 2017 to September 2022. There were 66 patients (13.75%) with pHLH, and the median age was 3.21years (0.17-12.92years). Variants in UNC13D (22/66, 33.33%), PRF1 (20/66, 30.30%) and XIAP (11/66, 16.67%) were the most common. More CNS involvement was observed in pHLH patients than in secondary hemophagocytic lymphohistiocytosis (sHLH) patients (50% vs. 25.3%, P = 0.001). Eight pHLH patients had isolated CNS-HLH at onset, which progressed to systemic HLH within 10-30days to several years. Among them, five patients who underwent hematopoietic stem cell transplantation (HSCT) survived without CNS sequelae, and the three patients who did not undergo HSCT died of disease progression or recurrence. Determination of natural killer (NK) cell cytotoxicity and CD107a levels had low sensitivity and specificity in the diagnosis of pHLH, especially in patients with PRF1 and XIAP mutations. The 3-year overall survival (OS) was significantly lower in pHLH patients than in sHLH patients (74.5% ± 14.7% vs. 89.2% ± 3.53%, P = 0.021) and in patients with CNS involvement than in those without (53.8% ± 26.07% vs. 94.4% ± 10.58%, P = 0.012). There was a significant difference in OS among pHLH patients with different gene variants (P = 0.032); patients with PRF1 variants had poor 3-year OS, and patients with XIAP variants had good 3-year OS (50% ± 28.22% and 100%, respectively). pHLH patients with distinct variants have different prognoses. Isolated CNS-HLH patients are easily misdiagnosed, and HSCT may be beneficial for these patients. Determination of NK cell cytotoxicity and CD107a levels cannot precisely distinguish pHLH from sHLH.

Clinical value of soluble fms-like tyrosine kinase 1 (sFlt-1) in adult secondary hemophagocytic lymphohistiocytosis.

Secondary hemophagocytic lymphohistiocytosis (sHLH) is a syndrome characterized by an excessive systemic inflammatory response, manifested by multiple organ dysfunction, lacking reliable immune biomarkers for predicting their inflammatory status and prognosis. Soluble fms-like tyrosine kinase 1 (sFlt-1) is associated with various inflammation-related diseases, including sepsis and severe organ failure. This study retrospectively included 32 adult sHLH patients diagnosed from January 2020 to December 2021. The expression of Flt-1 in peripheral blood CD14 + monocytes was detected by flow cytometry, and the level of plasma sFlt-1 was detected by ELISA. In our study, the results of flow cytometry reveal that the Flt-1 expression on CD14 + monocytes of peripheral blood from sHLH patients was higher than that in normal control. In plasma samples of sHLH patients, sFlt-1 levels were 677.8 (463.2-929.7) pg/mL, significantly higher than in normal controls 377.18 (350.4-424.6) pg/mL and sepsis group 378.3 (257.0-499.1) pg/mL. Besides, a positive correlation was found between sFlt-1 and IL-6 in sHLH patients. The analysis of univariate Cox regression indicated that sFlt-1 >681.5 pg/mL demonstrated unfavorable overall survival ( p = 0.022). Multivariate analysis demonstrated that sFlt-1 >681.5 pg/mL was an independent factor associated with OS ( p = 0.041) after adjustment for confounders. Restricted cubic spline confirmed a linear and positive association between sFlt-1 and mortality risk. Retrospective analysis showed that sFlt-1 was a promising prognostic factor.

Risk factors and prognosis of early death in secondary hemophagocytic lymphohistiocytosis.

The aim of our study was to summarize the clinical characteristics of early death patients with newly diagnosed secondary hemophagocytic lymphohistiocytosis (sHLH), analyze the risk factors of early death, and analyze the survival of patients. The clinical characteristics of 324 newly diagnosed sHLH patients admitted to the First Affiliated Hospital of Zhejiang University Medical College and Zhejiang Provincial Cancer Hospital from January 2014 to February 2021 were analyzed retrospectively. Analyze the independent risk factors of early death, compare the secondary diseases and treatment methods of patients with early death group and non early death group, and analyze the survival of all patients with sHLH. Among the 324 newly diagnosed patients with sHLH, 134 died early, with an early mortality rate of 41.4%. Comparing the clinical characteristics of patients with early death group and patients with non early death group, logistic regression model was used to conduct multifactor analysis. Age > 60years, Plt ≤ 20.0 × 109/L, APTT > 36.0s and LDH > 1000.0 U/L were independent risk factors for early death of newly diagnosed sHLH patients (P < 0.05). Comparing the secondary diseases and treatment methods between early death group and non early death group, the proportion of sHLH patients secondary to lymphoma was higher in early death group than that in non early death group (P < 0.05). The proportion of sHLH patients secondary to connective tissue disease and infection was lower in early death group than that in non early death group (P < 0.05), and the proportion of sHLH patients used hormone combined chemotherapy was lower in early death group than that in non early death group (P < 0.05). The median follow-up time of all patients was 12.0 (1-65) months. The 5-year OS rates of patients with age > 60years and age ≤ 60years were 25.8% and 49.6% respectively (P < 0.001); The 5-year OS rates of patients with Plt > 20.0 × 109/L and Plt ≤ 20.0 × 109/L were 52.5% and 25.5% respectively (P < 0.001); The 5-year OS rates of patients with APTT > 36.0s and APTT ≤ 36.0s were 34.5% and 57.4% respectively (P < 0.001); The 5-year OS rates of patients with LDH > 1000.0 U/L and LDH ≤ 1000.0 U/L were 23.3% and 56.3% respectively (P < 0.001). Age > 60years, Plt ≤ 20.0 × 109/L, APTT > 36.0s and LDH > 1000.0 U/L are independent risk factors for early death of sHLH patients. The early mortality of lymphoma associated HLH (LA-HLH) patients is high, and early use of hormone combined chemotherapy can reduce the early mortality.

Expression and Clinical Significance of Serum sFas/sFasL in Patients with Secondary Hemophagocytic Lymphohistiocytosis

To investigate the expression and clinical significance of soluble Fas (sFas) and sFasL in patients with secondary hemophagocytic lymphohistiocytosis (sHLH). From September 2015 to December 2020, 86 sHLH patients who met the HLH2004 diagnostic criteria were collected. They were divided into 55 cases in the MAHLH group and 31 cases in the NonMAHLH group according to the etiology. Thirty healthy persons were chosen as the normal control group, and 20 patients with systemic lupus erythematosus (SLE) were chosen as the disease control group. The expression levels of sFas and sFasL in the serum of patients with each group were detected by ELISA, and the clinical data were collected for statistical analysis. The significance of sFas and sFasL in sHLH was analyzed by ROC curve. Serum levels of sFas and sFasL in patients with newly diagnosed sHLH were significantly higher than those in disease control group and normal control group (P<0.01). The levels of sFas and sFasL in MAHLH group were significantly higher than those in nonMAHLH (infection related HLH and autoimmune disease related HLH) group (P<0.01). The serum levels of sFas and sFasL in 17 newly treated patients with sHLH (17/86) after treatment were significantly lower than those before treatment (P<0.01). The serum sFas level in newly diagnosed sHLH patients was positively correlated with SF(r=0.35), sCD25(r=0.79) and sFasL(r=0.73). The serum sFasL level was positively correlated with SF(r=0.39), sCD25(r=0.64) and sFas(r=0.73). Compared with the NonMAHLH group, the area under the ROC curve was 0.707 (95% CI: 0.593-0.821) (P=0.0015). The optimal critical value for diagnosing MAHLH by sFas level was 12 743 pg/ml, and the sensitivity and specificity were 70.9% and 71% respectively. Compared with the NonMAHLH group, the area under the ROC curve was 0.765(95% CI: 0.659-0.87)(P<0.01). The median OS time of sFas high expression group (≥16798.5 pg/ml) and sFasL high expression group (≥4 785 pg/ml) was significantly shorter than that of the low expression group (P<0.001). Serum levels of sFas and sFasL can be used for the early diagnosis and differential diagnosis of sHLH disease, and are the factor related to the poor prognosis of sHLH.

Prognostic value of lipid profile in adult hemophagocytic lymphohistiocytosis.

Adult secondary hemophagocytic lymphohistiocytosis (sHLH) is a rare clinical syndrome with a high mortality rate. Currently, there are no feasible prognostic factors to clinically predict untreated sHLH patients' prognosis. Our objective was to characterize the lipid profile of adult sHLH patients and to determine the relationship with overall survival. We retrospectively analyzed 247 patients with newly diagnosed sHLH from January 2017 to January 2022 according to the HLH-2004 criteria. Multivariate Cox regression analyses and restricted cubic splines were conducted to evaluate the prognostic value of the lipid profile. The median age of all patients was 52 years, and the commonest cause of sHLH in our cohort was malignancy. During a median follow-up of 88 (interquartile ranges, 22-490) days, 154 deaths occurred. The univariate analysis confirmed total cholesterol (TC) ≤ 3 mmol/L, triglycerides (TG) > 3.08 mmol/L, high-density lipoprotein cholesterol (HDL-c) ≤ 0.52 mmol/L, and low-density lipoprotein cholesterol (LDL-c) ≤ 2.17 mmol/L were associated with an inferior survival. In a multivariate model, HDL-c, hemoglobin, platelet, fibrinogen, and soluble interleukin-2 receptor were considered as independent factors. Additionally, the restricted cubic spline analyses indicated an inverse linear association between HDL-c and the risk of mortality in sHLH. Lipid profiles, which were low-cost and readily available promising biomarkers, were strongly associated with the overall survival in adult sHLH patients.

Identification and Characterization of a Retrospective Cohort of Secondary Hemophagocytic Lymphohistiocytosis (sHLH) Patients in the US

Introduction: Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening hyperinflammatory syndrome induced by aberrantly activated myeloid and T cells. HLH may be primary (i.e., due to genetic mutations) which typically presents in children, or secondary (i.e., triggered by an infection, malignancy, or rheumatologic condition) which is most common in adults. Without treatment, HLH is universally fatal; even with existing treatment, overall mortality ranges from 50-75%. Most of our understanding of HLH comes from studies in the pediatric population, and limited information is available on the diagnosis and treatment of patients with secondary HLH (sHLH). The aim of this study is to compile a historical cohort of sHLH patients from large US medical systems to better understand and refine the sHLH clinical definition, describe the epidemiology (including incidence, prevalence, and natural history of the disease), and characterize demographic, clinical, treatment characteristics, survival, and healthcare resource utilization (HRU) of the cohort compared with a matched comparison group. Methods: A historical cohort study was designed to identify sHLH patients aged ≥12 years from de-identified Electronic Medical Record (EMR) systems at health care centers in the US. The EMR systems track patients longitudinally over multiple years and are linked at the patient level by a unique identifier that is consistent across service locations and time. Three different methods (Figure 1) and chart reviews were used to enable identification of all possible sHLH patients and to better understand initial recorded diagnosis, differences in treatment and outcomes, and to determine a simpler system for accurate identification of sHLH cases in the healthcare system. As sHLH is a rare disorder that can be complex to diagnose and treat, these algorithms were developed to identify patients that may or may not have been assigned an ICD code for HLH. Approximately 5.4 million unique patient records were reviewed. Comparison of patients without sHLH were also identified from the EMR systems, matched on birth year, sex, and county of residence. Results: Patient electronic data from 2009-2021 were reviewed using all three methods. Of >800,000 unique inpatient records, 903 unique de-duplicated patients were identified for chart review. 57 patients were identified using HLH-related ICD codes (Method 1). An additional 846 patients were identified using HLH-related treatments (dexamethasone and etoposide) and elevated ferritin (≥1,000 to <10,000 ng/mL) in patient charts (Method 2) and/or by elevated ferritin (≥10,000 ng/mL) or sCD25 lab test ordered (with cohorts stratified by sCD25 lab values ≤3,900 U/mL and >3,900 U/mL) (Method 3). Potential HLH patient charts were then adjudicated via clinician review using HLH-2004 criteria and clinical judgment. Conclusion: Since sHLH is a rare, heterogenous, and complex disease to diagnosis and treat, HLH-related ICD codes (Method 1) may not be sufficient to capture the spectrum of sHLH patients. Both HLH-related treatments in charts (Method 2) and elevated ferritin and sCD25 values (Method 3) could prove useful in identifying additional sHLH patients. Moreover, Method 3 could show promise as a simplified strategy for identifying and diagnosing patients with sHLH. This process could inform the clinical definition and true burden of sHLH, particularly those patients who never received an sHLH diagnosis, as well as the clinical, demographic, and treatment characteristics and outcomes of this unique patient population. Figure 1. Flow Diagram of Patient Eligibility and MethodsFigure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

A Study on Early Death Prognosis Model in Adult Patients with Secondary Hemophagocytic Lymphohistiocytosis.

Background The mortality risks for secondary hemophagocytic lymphohistiocytosis in the induction stage and investigated prognostic factors need to be further discussed. Objective The aim of this study is to establish a clinical model for predicting early death in adult patients with secondary hemophagocytic lymphohistiocytosis. Design, Participants, and Main Measures. The baseline characteristics, laboratory examination results, and 8-week survival rate of 139 adult sHLH patients diagnosed from January 2018 to December 2018 were analyzed retrospectively, and a prognostic model was constructed with low-risk (score 0–2), medium-risk (score 3), and high-risk (score ≥ 4) as parameters. Key Results. Univariate analysis confirmed that early death was not related to the type of HLH but significantly related to the patient's response to first-line treatment. The peripheral blood cell count was significantly decreased, C-reactive protein was higher, glutamyl transpeptidase and total bilirubin were higher, albumin was significantly lower, urea nitrogen was higher, hypocalcemia and hyponatremia, deep organ hemorrhage and D-dimer increased, cardiac function damage and HLH central involvement, sCD25 increased, and EB virus infection were predictive factors of early death. In the multivariate model, patients' response to first-line treatment was a good predictor of overall survival, and hypocalcemia and deep organ bleeding were associated with poor survival. The risk factors were scored and graded according to the risk ratio. The 8-week overall survival rates of the low-risk group (82 cases), medium-risk group (36 cases), and high-risk group (21 cases) were 85.4%, 52.8%, and 23.8%, respectively (P < 0.001). Conclusions The early death of sHLH patients is closely related to some laboratory examination results. Attention should be paid to identify high-risk patients, choose effective first-line induction therapy, achieve deep remission as soon as possible, prevent deep organ bleeding, correct electrolyte disorders, and improve the early survival rate of sHLH patients.

18F-FDG PET/CT for Identifying the Potential Primary Diseases and Predicting Prognosis of Secondary Hemophagocytic Lymphohistiocytosis in Children.

Hemophagocytic lymphohistiocytosis (HLH) is a rare, potentially fatal illness, which can be divided into primary HLH (pHLH) and secondary HLH (sHLH). pHLH can be driven by genetic defections. Moreover, the sHLH is usually be triggered by malignancy or non-malignancy diseases. Sixty-two newly diagnosed sHLH patients with known etiology and those who underwent 18F-FDG PET/CT examination from July 2018 to December 2020 were retrospectively analyzed. They were divided into malignancy-associated HLH (M-HLH, n = 13) and non-malignancy-associated HLH (NM-HLH, n = 49). The metabolic parameters of the liver (Li), spleen (Sp), bone marrow (BM), lymph nodes (LN), and their ratios to the liver background (LiBG) and mediastinum (M) were compared between two groups. These metabolic parameters were evaluated for correlation with laboratory parameters and prognostic parameters. We found that the SUVmax-LN/Sp/Li and SUVmean-Sp in M-HLH were significantly higher than those in NM-HLH (P=0.031, 0.035, 0.016, and 0.032). The malignant disease should be considered when SUVmax-LN was higher than 4.41 (sensitivity 61.5%, specificity 81.6%). Hypermetabolic lesions in extranodal organs were more likely to occur in M-HLH than in NM-HLH (P=0.011). IFN- γ was positively correlated with SUVmax-BM/Li/Sp and SUVmean-BM/Li/Sp (P < 0.05). Ferritin, sCD25, IL-6, and IL-10 were positively correlated with SUVmax-Sp and SUVmean-Sp (P < 0.05). In Epstein–Barr virus-associated HLH (EBV-HLH), the SUV parameters of bone marrow were significantly correlated with a poor 2-week treatment response, overall survival, and event-free survival (P < 0.05). We conclude that some 18F-FDG PET/CT metabolic parameters can help identify the etiology of sHLH in children and provide directions for further inspection. The malignant disease should be considered when the SUVmax-LN is higher than 4.41 and hypermetabolic lesions occur in extranodal organs. In EBV-HLH, a higher SUV of bone marrow is associated with a poorer prognosis.

Expression and Significance of Serum Mir-146a and Mir-30e in Patients with Secondary Hemophagocytic Lymphohistiocytosis

ObjectiveHemophagocytic lymphohistiocytosis (HLH) is a clinical syndrome which is caused by uncontrolled activation and proliferation of CD8+ T cell , and abundant releasing of in inflammatory cytokines. It has been confirmed that miR-146a is widely participate in the regulation of intensity of inflammatory response, while miR-30e is related to the regulation of NK cell cytotoxicity. In this study, RT-PCR was used to detect the expression of serum miR-146a and miR-30e in patients with secondary HLH (sHLH). Their correlation with clinical data, and diagnosis and prognosis value in sHLH patients were explored. In addition, their relation with the proportion of cytotoxic lymphocyte subsets and the expression of perforin were explored.MethodsA total of 35 patients with sHLH and 10 healthy controls were enrolled in this study. Serum expression levels of miR-146a and miR-30e were detected by using RT-PCR. The expression of perforin protein oncytotoxic lymphocytes and the proportion of cytotoxic lymphocyte subsets were tested by flow cytometry. The clinical data of sHLH patients were collected.Results(1) The serum expression level of miR-146a in the newly diagnosed sHLH group was significantly lower than that of healthy control group (P <0.001); the serum expression level of miR-30e in the newly diagnosed sHLH group was significantly lower than that of healthy control group (P <0.001). (2) The serum expression level of miR-146a and miR-30e in the lymphoma-associated HLH group, the infection- associated HLH group, and the autoimmune-associated HLH group were compared group by group, however no significant difference was found (P >0.05). (3) ROC analysis revealed that the serum expression level of miR-146a can effectively identify sHLH patients from healthy people, with area under the curve (AUC) was 0.931; the serum expression level of miR-30e can effectively identify sHLH patients from healthy people, with area under the curve (AUC) was 0.914. (4) Correlation analysis was applied and no correlation was found between the serum expression level of miR-146a and miR-30e, and Age, WBC, HB, PLT, SF, ALB, ALT, AST, LDH, FIB, TG, ESR, sCD25, CRP level in the newly diagnosed sHLH (P >0.05). (5) According to the median of serum expression level, sHLH patients were divided in to Low expression group and High expression group. OS analysis was applied and revealed that there was no significance difference between the Low miR-146a expression group and the High miR-146a expression group (P >0.05); meanwhile there was no significance difference between the low miR-30e expression group and the high miR-30e expression group (P >0.05). However, sHLH patients were divided in to Low miR-30e/miR-146a group and High miR-30e/miR-146a group according to the median of miR-30e/miR-146a. The OS of Low miR-30e/miR-146a group was significantly longer than High miR-30e /miR-146a group (P=0.022). (6)The proportion of CD8+ T cell in Low miR-146a group was significantly lower than that in High miR-146a group (P = 0.016). The serum exression level of miR-146a was corelated with the proportion of CD8+ T cell (r=0.734, P = 0.007). However, the proportion of cytotoxic lymphocyte subsets in Low miR-146a group has no significant difference with that in Low miR-146a group (P >0.05); the serum exression level of miR-30e has no corelation with the proportion of cytotoxic lymphocyte subsets (P >0.05). (7) The expression of perforin in cytotoxic lymphocyte subsets in Low miR-30e group has no significant difference with that in Low miR-30e group (P >0.05); the serum exression level of miR-30e has no corelation with the expression of perforin in cytotoxic lymphocyte subsets (P >0.05).ConclusionThe serum expression level of miR-146a and miR-30e in the newly diagnosed sHLH group was significantly decreased, which is important in the differential diagnosis of sHLH. Individuals with lower serum expression level of miR-146a and miR-30e were more likely to be sHLH patients. The ratio of miR-30e and miR-146a (miR-30e /miR-146a) can indicate the prognosis of sHLH patients. The prognosis of sHLH patients with lower miR-30e /miR-146a was better than that of sHLH patients with higher miR-30e /miR-146a. The serum exression level of miR-146a was corelated with the proportion of CD8+ T cell. The serum exression level of miR-146a was corelated with the proportion of CD8+ T cell. Therefore, miR-146a may play a role in the deficiency of CD8+ T cell in the pathogenesis of sHLH. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Exhaustion of CD8+T Lymphocytes Plays a Critical Role in the Pathogenesis of Secondary Hemophagocytic Lymphohistiocytosis

To investigate the changes in function of CD8+ T cell subsets, and explore its significance in pathogenesis of secondary hemophagocytic lymphohistiocytosis (sHLH). Flow cytometry was used to detect the expressions of PD-1, TIM-3, and LAG-3, which were the markers of exhausted CD8+ T cell, as well as the secretion levels of interferon γ (IFN-γ) and expression of ΔCD107a after the stimulation; the numbers of effector-memory CD8+ T cells, regulatory T cells and double negative T cells were also detected. The expressions of inhibitory receptors (PD-1, TIM3 and LAG-3) on CD8+ T cells of sHLH patients were 40.73±22.64, 15.97±14.45 and 0.73 (0-37.41), respectively, which were significantly higher than those of the control group (P<0.001). In contrast, the expression of ΔCD107a (4.49±2.71 vs 6.07±2.14, P=0.035) and secretion level of IFN-γ (37.30±24.46 vs 55.17±22.23, P=0.034) were significantly lower. The number of effector-memory CD8+ T cells in sHLH patients was also lower as compared with that in control group (14.35±10.37 vs 22.92±11.12, P=0.016). But there was no significant difference in the number of regulatory T cell and double negative T cell. In addition, the expressions of PD-1, TIM3 and LAG-3 in active stage of sHLH were 38.09±21.87, 14.35±13.70 and 0.82 (0-13.22), respectively, which were significant higher than those in remission stage [24.27±17.23 (P=0.03), 8.64±5.60 (P=0.014) and 0.13 (0-3.69)]. The exhausted CD8+ T lymphocytes may play a critical role in the development of sHLH.

A Minimal Parameter Set Facilitating Early Decision-making in the Diagnosis of Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening immune dysregulation syndrome characterized by uncontrolled immune cell activation. Timely diagnosis is important, since early treatment can improve survival rates. However, completing all assessments needed to reach ≥5 positive criteria out of the 8 HLH-2004 criteria can be time consuming and may delay timely initiation of treatment. Hence, we applied a data-driven approach to identify a minimal parameter set for early decision-making towards the initiation of HLH-specific treatment. We retrospectively evaluated 165 patients from five Dutch tertiary hospitals with suspected HLH. Sixteen pHLH (median age 0.5 years) and 70 sHLH patients (median age 8.7 years) were identified using the HLH-2004 criteria. Clustering analysis and multi-receiver operator characteristics were used to identify parameters distinctive of HLH. The presence of either increased ferritin, cytopenia in ≥2 lineages, or splenomegaly distinguished HLH from non-HLH cases with a negative predictive value of 100%. A minimal parameter set consisting of 2 major criteria (phagocytosis and splenomegaly) and 3 minor criteria (cytopenia, increased ferritin, and increased triglycerides/low fibrinogen) predicted HLH with 95% (88–99) sensitivity and 94% (86–98) specificity. This finding was replicated in an independent retrospective validation cohort of 109 US patients (n = 109). By dividing a subset of the HLH-2004 criteria into major and minor criteria, this strategy uses the evaluation of less than 5 criteria to quickly identify patients with HLH. When confirmed in a prospective setting, this approach could be of value for timely diagnosis and treatment of HLH.

Infection-associated Hemophagocytic Syndrome in Critically Ill Patients with COVID-19

Infection-associated hemophagocytic syndrome (IAHS), a severe complication of various infections, is potentially fatal. This study aims to determine whether IAHS occurs in critically ill patients with coronavirus disease 2019 (COVID-19). We conducted a retrospective observational study on 268 critically ill patients with COVID-19 between February 1st, 2020 and February 26th, 2020. Demographics, clinical characteristics, laboratory results, information on concurrent treatments and outcomes were collected. A diagnosis of secondary hemophagocytic lymphohistiocytosis (sHLH) was made when the patients had an HScore greater than 169. Histopathological examinations were performed to confirm the presence of hemophagocytosis. Of 268 critically ill patients with confirmed SARS-CoV-2 infection, 17 (6.3%) patients had an HScore greater than 169. All the 17 patients with sHLH died. The interval from the onset of symptom of COVID-19 to the time of a diagnosis of sHLH made was 19 days and the interval from the diagnosis of sHLH to death was 4 days. Ten (59%) patients were infected with only SARS-CoV-2. Hemophagocytosis in the spleen and the liver, as well as lymphocyte infiltration in the liver on histopathological examinations, was found in 3 sHLH autopsy patients. Mortality in sHLH patients with COVID-19 is high. And SARS-CoV-2 is a potential trigger for sHLH. Prompt recognition of IAHS in critically ill patients with COVID-19 could be beneficial for improving clinical outcomes.

Clinical features of 47 secondary hemophagocytic lymphohistiocytosis patients complicated with capillary leak syndrome.

The clinical features of patients with secondary hemophagocytic lymphohistiocytosis (sHLH) complicated with capillary leak syndrome (CLS) remain controversial. The data of 259 sHLH patients were retrospectively analyzed. The clinical manifestations, laboratory findings, treatment, and prognosis of the CLS-sHLH group and non-CLS-sHLH group were compared. The levels of fibrinogen, albumin, and serum calcium in the CLS-sHLH group were lower than in the non-CLS-sHLH group, and serum triglycerides in the CLS-sHLH group were higher than in the non-CLS-sHLH group (P < 0.05). Univariate analysis showed that fibrinogen level was an independent prognostic factor in sHLH patients complicated with CLS. The median survival time was significantly shorter in patients with fibrinogen ≤ 1.3 g/L than in patients with fibrinogen > 1.3 g/L (P < 0.05). Patients with improved CLS conditions in the CLS-sHLH group had significantly increased albumin and serum calcium after treatment (P < 0.05); patients without improved conditions in the CLS-sHLH group also had significantly increased albumin after treatment (P < 0.05), but the serum calcium did not change significantly (P > 0.05). sHLH patients complicated with CLS had significantly worse prognosis than without CLS. Significant reduction in fibrinogen may be an independent prognostic factor for poor prognosis in sHLH patients complicated with CLS.