Adult haemophagocytic syndrome

Enforced CARD11/MALT1 signaling in dendritic cells triggers hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome fueled by uncontrolled mononuclear phagocyte activity, yet the innate immune mechanisms driving HLH pathogenesis remain elusive. Germline gain-of-function (GOF) mutations in CARD11, a pivotal regulator of lymphocyte antigen receptor signaling, cause the lymphoproliferative disease B-cell expansion with NF-κB and T-cell anergy, which is frequently associated with HLH development. Given that CARD11 is physiologically expressed not only in lymphocytes but also in dendritic cells (DCs), we explored whether enforced CARD11 signaling in DCs contributes to immunopathology. We demonstrated that exclusive DC-intrinsic expression of CARD11-GOF in mice was sufficient to induce a lethal autoinflammatory syndrome that mimicked human HLH. Mechanistically, DC-intrinsic CARD11-GOF signaling triggered cell-autonomous inflammatory cytokine production via MALT1 paracaspase engagement. Genetic deletion of Malt1 in CARD11-GOF-expressing animals reversed the hyperinflammatory phenotype. These results highlight the significant role of enforced CARD11/MALT1 signaling in DCs as a contributor to HLH pathology and suggest potential therapeutic strategies for HLH treatment.

Malignancy-associated HLH: mechanisms, diagnosis, and treatment of a severe hyperinflammatory syndrome

Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory syndrome characterized by uncontrolled immune activation. While traditionally associated with genetic mutations affecting cytotoxic function, recent advances have highlighted the prevalence and significance of HLH in adults, particularly in hematologic malignancies. This review focuses on malignancy-associated HLH (M-HLH), a complex and challenging condition with a poor prognosis. The review explores four main subtypes of M-HLH: (1) HLH as the initial presentation of malignancy, (2) Chemotherapy Associated HLH, (3) Cytokine Release Syndrome (CRS) Associated HLH-like Syndrome, and (4) immune effector cell-associated HLH-like syndrome. Diagnosis is complicated by overlap with cancer symptoms and limitations of existing criteria. The Optimized HLH Inflammatory (OHI) index shows promise in early identification of hyperinflammation in new-onset hematologic malignancies. Treatment approaches must balance controlling hyperinflammation with addressing the underlying malignancy. Emerging therapies, including targeted agents like anakinra, ruxolitinib, and emapalumab, offer new management possibilities. This review examines the current understanding of M-HLH pathophysiology, diagnostic approaches, and treatment strategies for each subtype. It underscores the critical need for further research to unravel underlying mechanisms and establish evidence-based treatment protocols. Given the complexity of M-HLH, international collaborative efforts are essential to advance knowledge and improve patient outcomes.

SARS-CoV-2 reactivates fungal-associated Hemophagocytic lymphohistiocytosis: Case report and review of the literature

Hemophagocytic lymphohistiocytosis (HLH) is a rare disease characterized by the uncontrolled activation of the immune system, resulting in a high clinical mortality rate. A 56-year-old Chinese female presented at the emergency room with symptoms including fever, fatigue, nausea, vomiting, cough, shortness of breath, and chest tightness. Laboratory investigations demonstrated decreased levels of white blood cells, hemoglobin, and platelets while interleukin-6 and ferritin exhibited significant elevations. She was subsequently admitted to the hematology department, where she was diagnosed with HLH caused by a Candida infection. Following treatment with antifungal agents, glucocorticoids, antiemetics, diuretics, and hepatoprotective therapy, the patient's condition has shown improvement. However, after being infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the patient experienced a reactivation of HLH, resulting in a more severe clinical presentation and complications compared to the initial onset. Although the patient's condition improved after the administration of antiviral drugs, etoposide, glucocorticoids, cyclosporin, and intravenous immunoglobulin, this case highlights the possibility of disease reactivation during the recovery phase of HLH. This should raise the attention of medical professionals.

Clinical characterization of hemophagocytic lymphohistiocytosis caused by immune checkpoint inhibitors: a review of published cases

OBJECTIVE

An association exists between immune checkpoint inhibitors and hemophagocytic lymphohistiocytosis (HLH). Therefore, the main objective of this study was to collect data on this rare but potentially life-threatening immune-related adverse reaction to identify the medications that cause it, the clinical characteristics, and effective treatments.

METHODS

Literature in English and Chinese on immune checkpoint inhibitors causing HLH published from August 2014 to March 2024 was analyzed. Immune checkpoint inhibitors, immunotherapy, anti-PD-1, PD-L1 inhibitors, HLH, hemophagocytic lymphohistiocytosis, hemophagocytic syndrome keywords were used to find the literature on China Knowledge Network, Wanfang, PubMed and Emabase Databases.

RESULTS AND DISCUSSION

Twenty-four studies were included, with a total of 27 patients (18 males and 9 females) with a mean age of 58 years (range 26-86). The mean time to the onset of symptoms was 10.3 weeks (7 days-14 months). The main clinical characteristics were fever, cytopenia, splenomegaly, methemoglobinemia, hypofibrinogenemia, and bone marrow biopsy showed phagocytosis. Twenty-two patients improved after the treatment with steroids, cytokine blocking therapy and symptomatic treatment, four patients died, and one patient was not described.

CONCLUSION

HLH should be not underestimated as a potentially serious adverse effect of immune checkpoint inhibitors since appropriate treatments may save the life of patients.

Comprehensive evaluation of immune dysregulation in secondary hemophagocytic lymphohistiocytosis

Host immune dysfunction plays a crucial role in the onset, progression, and outcome of hemophagocytic lymphohistiocytosis (HLH). This study aimed to comprehensively evaluate the peripheral immune profiles in patients with newly diagnosed secondary hemophagocytic lymphohistiocytosis (sHLH), and explore their predictive value for patient prognosis. A total of 77 patients with sHLH were enrolled in this study, with 31 of them experiencing mortality. Flow cytometry was used to assess the percentages, absolute numbers, and phenotypes of lymphocyte subsets. Simultaneously, cytokine levels and routine laboratory indicators were also collected. In sHLH patients, lymphocyte subset absolute numbers were significantly impaired, accompanied by T cell hyperactivation, B cell hyperactivation, and increased plasmablast proliferation. Prognostic analysis revealed that lower CD8+ T cell percentages, elevated APTT, IL-6, IL-10 levels, and increased CD4+CD28null T cell proportions were associated with poor patient outcomes. The study demonstrates dysregulation in the counts and phenotypes of lymphocyte subsets in sHLH patients. Several key factors, including IL-6, IL-10, APTT, and various T cell percentages, have potential as prognostic markers and therapeutic targets in sHLH.

Macrophage activation syndrome in Sepsis: from pathogenesis to clinical management

BACKGROUND

Sepsis represents a significant global health and hygiene challenge. Excessive activation of macrophages in sepsis can result in certain patients displaying characteristics akin to those observed in Macrophage Activation Syndrome (MAS). MAS represents a grave immune system disorder characterized by persistent and severe inflammation within the body. In the context of sepsis, MAS presents atypically, leading some researchers to refer to it as Macrophage Activation-Like Syndrome (MALS). However, there are currently no effective treatment measures for this situation. The purpose of this article is to explore potential treatment methods for sepsis-associated MALS.

OBJECTIVE

The objective of this review is to synthesize the specific pathophysiological mechanisms and treatment strategies of MAS to investigate potential therapeutic approaches for sepsis-associated MALS.

METHOD

We searched major databases (including PubMed, Web of Science, and Google Scholar etc.) for literature encompassing macrophage activation syndrome and sepsis up to Mar 2024 and combined with studies found in the reference lists of the included studies.

CONCLUSION

We have synthesized the underlying pathophysiological mechanism of MALS in sepsis, and then summarized the diagnostic criteria and the effects of various treatment modalities utilized in patients with MAS or MALS. In both scenarios, heterogeneous treatment responses resulting from identical treatment approaches were observed. The determination of whether the patient is genuinely experiencing MALS significantly impacts the ultimate outcomes of therapeutic efficacy. In order to tackle this concern, additional clinical trials and research endeavors are imperative.

Clinical features and prognosis of chronic natural killer cell lymphoproliferative disorders

OBJECTIVE

To analyze the current treatment status and prognostic regression of the chronic NK cell lymphoproliferative disorder (CLPD-NK).

METHODS

We retrospectively analyzed the clinical features, treatment and prognosis of 18 patients with CLPD-NK who were treated at our Hospital between September 2016 and September 2022.

RESULTS

Eighteen patients were included: three patients were treated with chemotherapy, five patients underwent immune-related therapy, one patient was treated with glucocorticoids alone, five patients were administered granulocyte colony-stimulating factor, blood transfusion therapy, or anti-infection therapy, followed by observation and follow-up, and four patients were observed without treatment. Fifteen patients survived, including two patients who achieved complete remission (CR) and seven patients who achieved partial remission (PR), of whom one patient progressed to Aggressive NK-cell leukemia (ANKL) and sustained remission after multiple lines of treatment; three patients were not reviewed, of which one patient was still in active disease, three patients developed hemophagocytic syndrome during treatment and eventually died, one of them had positive Epstein-Barr virus (EBV) expression. The 5-years overall survival rate was 83%.

CONCLUSION

Most patients with CLPD-NK have inert progression and a good prognosis, whereas some patients have a poor prognosis after progressing to ANKL and combined with hemophagocytic syndrome. Abnormal NK cells invading the center suggest a high possibility of ANKL development, and immunosuppressants and hormones are effective treatments for this disease.

Prevalence, trends, and outcomes of hematological malignancies in patients with hemophagocytic lymphohistiocytosis

BACKGROUNDS

Hemophagocytic lymphohistiocytosis (HLH) is an acute, rapidly progressive systemic inflammatory disorder that often occurs secondary to hematological malignancies among other conditions in adults. Although the annual incidence of HLH is increasing, detailed epidemiological knowledge of HLH is still limited, especially in patients with hematological malignancies.

OBJECTIVES

To analyze the impact of hematological malignancies on the epidemiology and outcomes of HLH.

STUDY DESIGN

Data from the National Readmission Database (NRD) from 2011 to 2020 were analyzed to explore the epidemiological trends and in-hospital outcomes of HLH patients, particularly those with hematological malignancies.

RESULTS

Our analysis included 7579 HLH hospitalizations, with hematological malignancies implicated in 24.01% of cases. Our findings reveal a steady increase in HLH diagnoses from 145 cases in 2011 to 1848 in 2020, with the proportion linked to hematological malignancies remaining consistent. Patients with hematological malignancies-associated HLH exhibited higher rates of in-hospital mortality (31.6%) than those without (14.4%), and a higher 30-day readmission rate, underscoring a critical need for early detection and treatment revision.

CONCLUSIONS

Despite the increasing awareness and diagnosis of HLH, the prognosis of patients with HLH associated with hematological malignancies remains poor, highlighting the urgent need for improved management strategies and therapeutic interventions.

Comprehensive insights into tuberculosis-associated hemophagocytic lymphohistiocytosis: a systematic review

BACKGROUND

Tuberculosis-associated hemophagocytic lymphohistiocytosis (TB-HLH) presents significant challenges in diagnosis and treatment due to its complex interplay between TB and HLH. This systematic review aims to provide comprehensive insights into the epidemiology, clinical characteristics, and treatment outcomes of TB-HLH patients.

METHODS

We performed a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, searching PubMed, Scopus, Web of Science, and Embase up to May 16, 2023, without language restrictions. We included case reports and cases series on patients with both TB and HLH with documented treatment outcomes. Data were analyzed using descriptive statistics, chi-square or Fisher's exact tests, t-tests, and mortality rates. Significant variables (p < 0.05) from univariate analysis and clinically relevant factors were used in binary logistic regression to determine odds ratios, 95% confidence intervals, and p-values.

RESULTS

A total of 185 articles involving 213 patients were included. The overall mortality rate was 39%. Age ≥ 44 years and comorbidities were identified as independent risk factors for increased mortality (p = 0.005). Anti-tuberculosis treatment (ATT) combined with HLH-specific therapies, was associated with reduced mortality compared to ATT alone (p < 0.05), especially IVIG (p = 0.04).

CONCLUSION

Integrating ATT with HLH-specific therapies significantly enhances survival in TB-HLH patients. Additionally, IVIG plays a key role in improving outcomes. Age ≥ 44 years and comorbidities are critical risk factors for increased mortality. Early and high suspicion of TB-HLH is essential, especially in high TB burden regions or recent travel contexts. Future research should focus on prospective multicenter studies to validate our findings and develop standardized treatment strategies on TB-HLH.

PROSPERO

CRD42022364180.

Hemophagocytic lymphohistiocytosis: current treatment advances, emerging targeted therapy and underlying mechanisms

Hemophagocytic lymphohistiocytosis (HLH) is a rapidly progressing, life-threatening syndrome characterized by excessive immune activation, often presenting as a complex cytokine storm. This hyperactive immune response can lead to multi-organ failure and systemic damage, resulting in an extremely short survival period if left untreated. Over the past decades, although HLH has garnered increasing attention from researchers, there have been few advancements in its treatment. The cytokine storm plays a crucial role in the treatment of HLH. Investigating the detailed mechanisms behind cytokine storms offers insights into targeted therapeutic approaches, potentially aiding in early intervention and improving the clinical outcome of HLH patients. To date, there is only one targeted therapy, emapalumab targeting interferon-γ, that has gained approval for primary HLH. This review aims to summarize the current treatment advances, emerging targeted therapeutics and underlying mechanisms of HLH, highlighting its newly discovered targets potentially involved in cytokine storms, which are expected to drive the development of novel treatments and offer fresh perspectives for future studies. Besides, multi-targeted combination therapy may be essential for disease control, but further trials are required to determine the optimal treatment mode for HLH.

Macrophage Activation Syndrome

Macrophage activation syndrome (MAS) is a state of immune hyperactivation that can result in life-threatening multisystem end-organ dysfunction. Often termed a "cytokine storm," MAS occurs among the rheumatic diseases most typically in Still's disease but also in systemic lupus erythematosus and Kawasaki disease. MAS can also accompany infection, malignancy, and inborn errors of immunity. This review provides a practical, evidence-based guide to the understanding, recognition, and management of MAS in children and adults, with a primary focus on MAS complicating Still's disease.

Interleukin (IL)-1/IL-6-Inhibitor-Associated Drug Reaction With Eosinophilia and Systemic Symptoms (DReSS) in Systemic Inflammatory Illnesses

BACKGROUND

After introducing IL-1/IL-6 inhibitors, some patients with Still and Still-like disease developed unusual, often fatal, pulmonary disease. This complication was associated with scoring as DReSS (drug reaction with eosinophilia and systemic symptoms) implicating these inhibitors, although DReSS can be difficult to recognize in the setting of systemic inflammatory disease.

OBJECTIVE

To facilitate recognition of IL-1/IL-6 inhibitor-DReSS in systemic inflammatory illnesses (Still/Still-like) by looking at timing and reaction-associated features. We evaluated outcomes of stopping or not stopping IL-1/IL-6 inhibitors after DReSS reaction began.

METHODS

In an international study collaborating primarily with pediatric specialists, we characterized features of 89 drug-reaction cases versus 773 drug-exposed controls and compared outcomes of 52 cases stopping IL-1/IL-6 inhibitors with 37 cases not stopping these drugs.

RESULTS

Before the reaction began, drug-reaction cases and controls were clinically comparable, except for younger disease-onset age for reaction cases with preexisting cardiothoracic comorbidities. After the reaction began, increased rates of pulmonary complications and macrophage activation syndrome differentiated drug-reaction cases from drug-tolerant controls (P = 4.7 × 10-35 and P = 1.1 × 10-24, respectively). The initial DReSS feature was typically reported 2 to 8 weeks after initiating IL-1/IL-6 inhibition. In drug-reaction cases stopping versus not stopping IL-1/IL-6-inhibitor treatment, reaction-related features were indistinguishable, including pulmonary complication rates (75% [39 of 52] vs 76% [28 of 37]). Those stopping subsequently required fewer medications for treatment of systemic inflammation, had decreased rates of macrophage activation syndrome, and improved survival (P = .005, multivariate regression). Resolution of pulmonary complications occurred in 67% (26 of 39) of drug-reaction cases who stopped and in none who continued inhibitors.

CONCLUSIONS

In systemic inflammatory illnesses, recognition of IL-1/IL-6-inhibitor-associated reactions followed by avoidance of IL-1/IL-6 inhibitors significantly improved outcomes.

Diagnostic accuracy of bone marrow blood evaluation in haemophagocytic lymphohistiocytosis paediatric patients

INTRODUCTION

Haemophagocytic lymphohistiocytosis (HLH) is a rare and serious immunological syndrome that involves a strong activation of cytotoxic T lymphocytes and macrophages. HLH determines a cytokine-mediated tissue injury with a contemporary multi-organ failure and a high fatality rate.

MATERIAL AND METHODS

A retrospective study was performed considering the medical records of paediatric patients who underwent a bone marrow aspirate for suspect HLH. The biomarkers evaluated were among those included in the HLH-2004. Lactate dehydrogenase (LD) was also evaluated. Haemophagocytosis was evaluated in bone marrow blood smear slides.

RESULTS

Enrolled were 11 patients included in the HLH group and 8 patients as controls. Haemoglobin and fibrinogen resulted lower in HLH patients than in controls, while blood triglycerides, serum ferritin and LD resulted increased. Blood triglycerides and fibrinogen discriminated HLH cases perfectly, with a sensitivity and specificity of 100%. Ferritin had a sensitivity of 100% and a specificity of 83% (cut off ≥3,721 µg/L) and LD of 73% and of 100% (the cut off ≥1,903 U/L). Haemoglobin was found to have a sensitivity of 75% and a specificity of 100% (cut off ≤ 96 g/L). Total haemophagocytes cell counts were not different between patients and controls. Only the increased number of phagocytized nucleated red blood cells (NRBC) was found to be significantly increased in the patients. Erythrocytes phagocytosis (≥4/1,000 cells) only tended towards significance.

CONCLUSIONS

The blood biomarkers showed better diagnostic performance than the morphological evaluation. Among the different cell lineages engulfed by haemophagocytes, the best diagnostic performance was obtained by phagocytosed mature erythrocytes and immature nucleated erythrocytes.

Intravenous Anakinra for Treating Macrophage Activation Syndrome in Adult-Onset Still's Disease

Background

Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disease characterized by fever, rash, arthritis, and multi-organ involvement. Macrophage activation syndrome (MAS), a serious complication of AOSD, poses significant diagnostic and therapeutic challenges.

Case Presentation

A 32-year-old male was diagnosed with AOSD in 2020 after being hospitalized for a fever of unknown origin and elevated liver enzymes. The patient was initially treated with corticosteroids and methotrexate but subsequently discontinued both treatment and follow-up. In September 2023, he presented with fever, sore throat, and elevated inflammatory markers. After screening for infections, methylprednisolone (MP) treatment was initiated because of AOSD activation. The following day, the patient was admitted to the intensive care unit due to an altered state of consciousness. Brain magnetic resonance imaging revealed brainstem involvement. Empirical treatments were initiated, including intravenous MP, and immunoglobulin therapy. Due to suspected macrophage activation syndrome (MAS), anakinra (ANA) infusion was initiated. Significant improvement was observed after the ANA infusion.

Conclusion

This case highlights the complex management of severe AOSD complications, emphasizing the role of early recognition, aggressive therapy, and multidisciplinary care in improving outcomes.

LEARNING POINTS

Macrophage activation syndrome (MAS) is a serious complication of adult-onset Still's disease characterized by systemic inflammation. Early recognition and prompt initiation of treatment are crucial due to the high mortality rate associated with MAS, especially when neurologic symptoms are present.Clinicians should not delay treatment pending confirmatory diagnostic tests when MAS is suspected, as early intervention can significantly impact patient outcomes.Anakinra, an interleukin-1 inhibitor, is typically administered subcutaneously but has shown promise when administered intravenously, particularly in severe cases of MAS.

CircMETTL3-156aa reshapes the glycolytic metabolism of macrophages to promote M1 polarization and induce cytokine storms in sHLH

Persistent macrophage activation and cytokine storms are critical causes for the rapid disease progression and high mortality rate of Secondary Hemophagocytic lymphohistiocytosis (sHLH). Identification of key regulatory factors that govern the activation of macrophages is vital. Plasma exosomal circular RNAs (circRNAs) are considered important biomarkers and potential therapeutic targets for various diseases, however, their function in sHLH is still unclear. In this study, we demonstrated for the first time that circMETTL3, derived from METTL3, is upregulated in sHLH patient plasma exosomes, which may plays an important role in the diagnosis of sHLH. Significantly, we also revealed that a novel peptide encoded by circMETTL3, METTL3-156aa, is an inducer of M1 macrophage polarization, which is responsible for the development of cytokine storms during sHLH. We then identified that METTL3-156aa binding with lactate dehydrogenase A (LDHA) and promotes M1 macrophage polarization by enhancing macrophage glycolysis. Additionally, the glycolysis metabolite lactate upregulates the cleavage factor SRSF10 expression by lactylation. This results in increased splicing of the pre-METTL3 mRNA, leading to an enchance in the production of cirMETTL3. Therefore, our results suggest that the circMETTL3/METTL3-156aa/LDHA/Lactate/SRSF10 axis forms a positive feedback loop and may be a novel therapeutic target for the treatment of sHLH.

Hemophagocytic lymphohistiocytosis induced by dabrafenib-trametinib in a patient with metastatic melanoma: a case report and pharmacovigilance analysis

Hemophagocytic lymphohistiocytosis (HLH) has been reported rarely with BRAF/MEK inhibitor combinations, including dabrafenib/trametinib. Postmarketing pharmacovigilance analyses evaluating outcomes associated with dabrafenib/trametinib-induced HLH are also lacking. Herein, we report a case of dabrafenib/trametinib-induced HLH in a patient with metastatic melanoma. Recovery of HLH-related symptoms was observed following drug discontinuation, supportive care, and corticosteroids. We also conducted a pharmacovigilance analysis of the USA Food and Drug Administration Adverse Event Reporting System (FAERS) to describe postmarketing cases of HLH with dabrafenib/trametinib exposure. There were 50 reports of HLH with dabrafenib/trametinib in FAERS. Most cases occurred in the setting of melanoma ( n  = 39; 78%) and most were reported in Europe ( n  = 39; 74%). Hospitalization was the most common outcome ( n  = 39; 78%) of this adverse event per FAERS. HLH is a rare complication of dabrafenib/trametinib, and clinicians should be aware and monitor for signs of this potentially serious and life-threatening adverse event.

Emapalumab as a therapeutic intervention for Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis: A case series

RATIONALE

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) is characterized by a severe cytokine storm, heightened inflammatory response, and immune-mediated damage to tissues and organs. Standard treatment protocols for hemophagocytic lymphohistiocytosis often fall short in effectively controlling EBV-HLH, leading to a need for novel therapeutic options. Emapalumab, a monoclonal antibody targeting interferon-gamma, has shown promise due to its targeted cytokine modulation capabilities and favorable safety profile. This study aimed to evaluate the efficacy and safety of emapalumab in pediatric patients with EBV-HLH.

PATIENT CONCERNS

The case series involved 4 pediatric patients diagnosed with EBV-HLH who did not achieve disease control despite receiving comprehensive treatment.

DIAGNOSES

All 4 pediatric patients were diagnosed with EBV-HLH.

INTERVENTIONS

Emapalumab was introduced as an adjunctive therapeutic intervention alongside the HLH-94 or L-DEP regimens for these patients.

OUTCOMES

Among the 4 patients, 1 experienced severe multiorgan dysfunction and opted to discontinue therapy. The remaining 3 patients showed controlled disease progression with significant clinical improvements following emapalumab administration. These improvements included reduced levels of inflammatory markers, normalization of blood counts and liver function, and decreased Epstein-Barr virus viral load.

LESSONS

The findings suggest that emapalumab may be an effective and safe treatment option for pediatric EBV-HLH. However, further research is necessary to confirm these outcomes, especially in critically ill patients.

Machine Learning of Laboratory Data in Predicting 30-Day Mortality for Adult Hemophagocytic Lymphohistiocytosis

BACKGROUND

Hemophagocytic Lymphohistiocytosis (HLH) carries a high mortality rate. Current existing risk-evaluation methodologies fall short and improved predictive methods are needed. This study aimed to forecast 30-day mortality in adult HLH patients using 11 distinct machine learning (ML) algorithms.

METHODS

A retrospective analysis on 431 adult HLH patients from January 2015 to September 2021 was conducted. Feature selection was executed using the least absolute shrinkage and selection operator. We employed 11 ML algorithms to create prediction models. The area under the curve (AUC), sensitivity, specificity, positive predictive value, negative predictive value, F1 score, calibration curve and decision curve analysis were used to evaluate these models. We assessed feature importance using the SHapley Additive exPlanation (SHAP) approach.

RESULTS

Seven independent predictors emerged as the most valuable features. An AUC between 0.65 and 1.00 was noted among the eleven ML algorithms. The gradient boosting decision tree (GBDT) algorithms demonstrated the most optimal performance (1.00 in the training cohort and 0.80 in the validation cohort). By employing the SHAP method, we identified the variables that contributed to the model and their correlation with 30-day mortality. The AUC of the GBDT algorithms was the highest when using the top 4 (ferritin, UREA, age and thrombin time (TT)) features, reaching 0.99 in the training cohort and 0.83 in the validation cohort. Additionally, we developed a web-based calculator to estimate the risk of 30-day mortality.

CONCLUSIONS

With GBDT algorithms applied to laboratory data, accurate prediction of 30-day mortality is achievable. Integrating these algorithms into clinical practice could potentially improve 30-day outcomes.

Immune biomarkers and secondary hemophagocytic lymphohistiocytosis: a scoping review protocol

OBJECTIVE

To identify immunological pathways and markers of severity of illness associated with clinical outcomes that may represent potential therapeutic targets in the management of secondary hemophagocytic lymphohistiocytosis.

INTRODUCTION

A broad range of immunomodulatory therapies is used to manage hemophagocytic lymphohistiocytosis, however the supporting evidence for these therapies is scarce. Identifying patients likely to experience more severe disease, or die, is currently extremely difficult, if not impossible. The identification of implicated cytokines in secondary disease can provide further support for the identification of high-risk patients and the development of targeted therapies.

INCLUSION CRITERIA

Studies reporting immune biomarker and cytokine measurement in adult patients (age >18 years) with secondary hemophagocytic lymphohistiocytosis.

METHODS

The proposed review will be conducted in line with the JBI methodology for scoping reviews. The MEDLINE (Ovid) and Embase (Ovid) databases will be searched, without date limitations. Data will be extracted using a data extraction tool developed by the reviewers. Relevant sources will be retrieved, and their citation details imported into the JBI System for the Unified Management, Assessment and Review of Information.

Etiological stratification and prognostic assessment of haemophagocytic lymphohistiocytosis by machine learning on onco-mNGS data and clinical data

Introduction

Hemophagocytic lymphohistiocytosis (HLH) is a rare, complicated and life threatening hyperinflammatory syndrome that maybe triggered by various infectious agents, malignancies and rheumatologic disorders. Early diagnosis and identification of the cause is essential to initiate appropriate treatment and improve the quality of life and survival of patients. The recently developed Onco-mNGS technology can be successfully used for simultaneous detection of infections and tumors.

Methods

In the present study, 92 patients with clinically confirmed HLH were etiologically subtyped for infection, tumor and autoimmunity based on CNV and microbial data generated by Onco-mNGS technology, and a predictive model was developed and validated for the differential diagnosis of the underlying disease leading to secondary HLH. Furthermore, the treatment outcomes of patients with HLH triggered by EBV infection and non-EBV infection were evaluated, respectively.

Results

The current study demonstrated that the novel Onco-mNGS can identify the infection and malignancy- related triggers among patients with secondary HLH. A random forest classification model based on CNV profile, infectious pathogen spectrum and blood microbial community was developed to better identify the different HLH subtypes and determine the underlying triggers. The prognosis for treatment of HLH patients is not only associated with CNV, but also with the presence of pathogens and non- pathogens in peripheral blood. Higher CNV burden along with frequent deletions on chromosome 19, higher pathogen burden and lower non-pathogenic microbes were prognosis factors that significantly related with unfavorable treatment outcomes.

Discussion

Our study provided comprehensive knowledge in the triggers and prognostic predictors of patients with secondary HLH, which may help early diagnosis and appropriate targeted therapy, thus improving the survival and prognosis of the patients.

Emapalumab Treatment in Patients With Rheumatologic Disease-Associated Hemophagocytic Lymphohistiocytosis in the United States: A Retrospective Medical Chart Review Study

OBJECTIVE

Rheumatologic disease-associated hemophagocytic lymphohistiocytosis (HLH), a rare, life-threatening, systemic hyperinflammatory syndrome, occurs as a complication of underlying rheumatologic disease. Real-world evidence is lacking on emapalumab, a fully human monoclonal antibody that neutralizes the proinflammatory cytokine interferon-γ, approved for treating patients with primary HLH.

METHODS

REAL-HLH, a retrospective medical chart review study conducted across 33 US hospitals, assessed real-world treatment patterns and outcomes in patients with HLH treated with one or more dose of emapalumab between November 20, 2018, and October 31, 2021. Data are presented for the subset of patients with rheumatologic disease-associated HLH.

RESULTS

Fifteen of 105 patients (14.3%) had rheumatologic disease-associated HLH. Of these, nine (60.0%) had systemic juvenile idiopathic arthritis, and one (6.7%) had adult-onset Still disease. Median (range) age at HLH diagnosis was 5 (0.9-39) years. Most patients (9 of 15; 60.0%) initiated emapalumab in an intensive care unit. Emapalumab was most frequently initiated for treating refractory or recurrent (10 of 15; 66.7%) disease. Most patients received HLH-related therapies before (10 of 15; 66.7%) and concurrently with (15 of 15; 100.0%) emapalumab. Emapalumab-containing regimens stabilized or achieved physician-determined normalization of most laboratory parameters, including absolute neutrophil count and absolute lymphocyte count (13 of 14; 92.9%), chemokine ligand 9 (9 of 11; 81.8%), and platelets and alanine transaminase (11 of 14; 78.6%), and reduced glucocorticoid dose by 80%. Overall survival and 12-month survival probability from emapalumab initiation were 86.7%.

CONCLUSION

Emapalumab-containing regimens stabilized or normalized most key laboratory parameters, reduced glucocorticoid dose, and were associated with low disease-related mortality, thereby demonstrating potential benefits in patients with rheumatologic disease-associated HLH.

Lymphoma-associated hemophagocytic syndrome: a retrospective, single-center study of 86 patients

To explore the clinical features, treatment, and prognosis of patients with lymphoma-associated hemophagocytic syndrome (LAHS) in a real-world clinical setting. We retrospectively examined LAHS patients diagnosed at our center between January 2016 and August 2023, focusing primarily on their clinical features, therapeutic approaches, overall response rate (ORR), and overall survival (OS). A combination of univariate and multivariate analyses was conducted to identify potential prognostic factors. A total of 86 patients diagnosed with LAHS were included to evaluate clinical characteristics and prognostic factors. Patients with T/NK cell lymphoma had a higher probability of developing hemophagocytic syndrome (HPS) during the clinical process than those with B cell lymphoma. The median survival time was 55 days for all patients, and 47 and 81 days for the T/NK cell LAHS and B cell LAHS cohorts, respectively (P = 0.025). Among the patients evaluated, the ORR was 42.2%. Patients starting with anti-lymphoma treatment had a better, albeit not significant, ORR than those beginning with anti-HPS treatment. In the univariate analysis, T/NK cell LAHS (P = 0.027), HPS onset at relapse (P = 0.036), higher baseline plasma EBV-DNA levels (> 4,000 copies/mL, P = 0.034), and treatments including cytokine adsorption and ruxolitinib (P < 0.001 and P = 0.017, respectively) were potentially associated with worse OS, while corticosteroid therapy benefited OS. In the multivariate analysis, T/NK cell LAHS (adjusted hazard ratio (aHR) = 2.007), cytokine adsorption therapy (aHR = 4.547), and corticosteroid therapy (aHR = 0.118) were independently associated with mortality. T/NK cell lymphoma was the main cause of LAHS and carried a worse prognosis. Whether anti-lymphoma or anti-HPS treatment should start first still requires prospective studies with larger sample sizes. The key point in controlling HPS is to block the cytokine storm promptly. Corticosteroid therapy is both effective and accessible and should be used early and in sufficient quantities.

Fatal hemophagocytic lymphohistiocytosis with intravascular large B-cell lymphoma following coronavirus disease 2019 vaccination in a patient with systemic lupus erythematosus: an intertwined case

Hemophagocytic lymphohistiocytosis (HLH) has been recognized as a rare adverse event following the coronavirus disease 2019 (COVID-19) vaccination. We report a case of neuropsychiatric symptoms and refractory HLH in a woman with systemic lupus erythematosus (SLE) after receiving her COVID-19 vaccine treated with belimumab, later found to have intravascular large B-cell lymphoma (IVLBCL) at autopsy. A 61-year-old woman with SLE was referred to our hospital because of impaired consciousness and fever. One month prior to consulting, she received her second COVID-19 vaccine dose. Afterward, her consciousness level decreased, and she developed a high fever. She tested negative for SARS-CoV-2. Neuropsychiatric SLE was suspected; therefore, glucocorticoid pulse therapy was initiated on day 1 and 8. She had thrombocytopenia, increased serum ferritin levels and hemophagocytosis. The patient was diagnosed with HLH and treated with etoposide, dexamethasone and cyclosporine. Despite treatment, the patient died on day 75; autopsy report findings suggested IVLBCL as the underlying cause of HLH. Differentiating comorbid conditions remains difficult; however, in the case of an atypical clinical presentation, other causes should be considered. Therefore, we speculate that the COVID-19 vaccination and her autoimmune condition may have expedited IVLBCL development.

Hemophagocytic Lymphohistiocytosis in Visceral Leishmaniasis: A Rare yet Treatable Complication

Hemophagocytic lymphohistiocytosis (HLH) is a rare debilitating condition that can be triggered by an infectious cause, often linked to the Epstein-Barr virus (EBV). In this case, we evaluated a patient with pancytopenia. The bone marrow aspiration revealed the presence of amastigotes and active hemophagocytosis, indicating that the HLH was induced by a Leishmania infection. The patient was treated with lyophilized amphotericin B followed by miltefosine, which effectively resolved the infection and HLH. This case report underscores the presentation and findings of Leishmania-induced HLH, as well as the successful treatment approach that led to improved patient outcomes.

The effectiveness of the doxorubicin-etoposide-methylprednisolone regimen for adult HLH secondary to rheumatic disease

To investigate the efficacy of the doxorubicin-etoposide-methylprednisolone, DEP) regimen as an effective treatment for adult Hemophagocytic Lymphohistiocytosis secondary to rheumatic disease and analyze prognosis in these patients. Fifty-eight adult patients diagnosed with Hemophagocytic Lymphohistiocytosis secondary to rheumatic disease admitted to Beijing Friendship Hospital from 1st Jan. 2018 to 31st Dec. 2022 were retrospectively included in this study. Patients were grouped according to previous treatment. Clinical data and laboratory characteristics of patients were retrospectively analyzed. The efficacy was evaluated every 2 weeks after initiating the first course of the DEP regimen and until the last inpatient or 31st Dec. 2023. 26 patients were included in Group A and 32 patients were included in Group B due to the previous treatment. After the first course of the DEP regimen, the overall response rate of all patients was 82.8%, with 13.8% in complete response and 69% in partial response. There was no significant statistical objective response rate between the two groups after the DEP regimen, except at 2-week. Serum ferritin, sCD25, ALT, AST, and DBIL concentrations were significantly lower at 2, 4 and 6-week than pre-treatment (P < 0.05). The overall mortality rate is 20.7% (12/58). Importantly, advanced age, initial level of HB and PLT, and central nervous system (CNS) involvement were independent poor risk factors affecting OS in bivariate analysis. The DEP regimen is effective for adult HLH secondary rheumatic disease with a high overall rate and accepted side effects.

A brief overview of SARS-CoV-2 infection and its management strategies: a recent update

The COVID-19 pandemic has become a global health crisis, inflicting substantial morbidity and mortality worldwide. A diverse range of symptoms, including fever, cough, dyspnea, and fatigue, characterizes COVID-19. A cytokine surge can exacerbate the disease's severity. This phenomenon involves an increased immune response, marked by the excessive release of inflammatory cytokines like IL-6, IL-8, TNF-α, and IFNγ, leading to tissue damage and organ dysfunction. Efforts to reduce the cytokine surge and its associated complications have garnered significant attention. Standardized management protocols have incorporated treatment strategies, with corticosteroids, chloroquine, and intravenous immunoglobulin taking the forefront. The recent therapeutic intervention has also assisted in novel strategies like repurposing existing medications and the utilization of in vitro drug screening methods to choose effective molecules against viral infections. Beyond acute management, the significance of comprehensive post-COVID-19 management strategies, like remedial measures including nutritional guidance, multidisciplinary care, and follow-up, has become increasingly evident. As the understanding of COVID-19 pathogenesis deepens, it is becoming increasingly evident that a tailored approach to therapy is imperative. This review focuses on effective treatment measures aimed at mitigating COVID-19 severity and highlights the significance of comprehensive COVID-19 management strategies that show promise in the battle against COVID-19.

Enhancing diagnostic precision in EBV-related HLH: a multifaceted approach using 18F-FDG PET/CT and nomogram integration

BACKGROUND

The hyperinflammatory condition and lymphoproliferation due to Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) affect the detection of lymphomas by 18F-FDG PET/CT. We aimed to improve the diagnostic capabilities of 18F-FDG PET/CT by combining laboratory parameters.

METHODS

This retrospective study involved 46 patients diagnosed with EBV-positive HLH, who underwent 18F-FDG PET/CT before beginning chemotherapy within a 4-year timeframe. These patients were categorized into two groups: EBV-associated HLH (EBV-HLH) (n = 31) and EBV-positive lymphoma-associated HLH (EBV + LA-HLH) (n = 15). We employed multivariable logistic regression and regression tree analysis to develop diagnostic models and assessed their efficacy in diagnosis and prognosis.

RESULTS

A nomogram combining the SUVmax ratio, copies of plasma EBV-DNA, and IFN-γ reached 100% sensitivity and 81.8% specificity, with an AUC of 0.926 (95%CI, 0.779-0.988). Importantly, this nomogram also demonstrated predictive power for mortality in EBV-HLH patients, with a hazard ratio of 4.2 (95%CI, 1.1-16.5). The high-risk EBV-HLH patients identified by the nomogram had a similarly unfavorable prognosis as patients with lymphoma.

CONCLUSIONS

The study found that while 18F-FDG PET/CT alone has limitations in differentiating between lymphoma and EBV-HLH in patients with active EBV infection, the integration of a nomogram significantly improves the diagnostic accuracy and also exhibits a strong association with prognostic outcomes.

A Retrospective Study: Evaluating the Impact of the COVID-19 Pandemic on Inflammatory Markers in Hospitalized Patients

BACKGROUND

The COVID-19 pandemic has had a significant impact globally, and understanding the relationship between inflammatory markers and disease progression is crucial for effective management. This retrospective study aimed to examine the association between various inflammatory markers, such as C-reactive protein (CRP), the erythrocyte sedimentation rate (ESR), lactate dehydrogenase (LDH), D-dimer, ferritin, and procalcitonin (PCT), and the characteristics of disease progression and outcomes in individuals affected by COVID-19.

METHODS

This study collected raw data from 470 patients who tested positive for SARS-CoV-2 using RT-PCR.

RESULTS

The logistic regression analysis revealed that elevated LDH levels were associated with male gender, ICU admission, low oxygen saturation (O2 < 93%), the need for mechanical ventilation, death, and the presence of lung infiltrates. Higher D-dimer levels were associated with older age, diabetes mellitus, cardiac disease, and low oxygen saturation. Ferritin levels were significantly associated with older age, ICU admission, low oxygen saturation, mechanical ventilation, and lung infiltrates. In contrast, CRP was only significant regarding lung infiltrates and procalcitonin levels were not significantly associated with any of the examined factors.

CONCLUSION

This study highlights the importance of monitoring key inflammatory markers, such as LDH, D-dimer, and ferritin, as they are significantly associated with the severity of COVID-19 illness. These findings can inform clinical decision-making and guide the development of targeted interventions to improve patient outcomes.

Hemophagocytic lymphohistiocytosis secondary to visceral leishmaniasis: A case report of a rare complication of visceral leishmaniasis

Hemophagocytic lymphohistiocytosis (HLH) is a rare, potentially life-threatening clinical syndrome characterized by hyperactivation of inflammatory mediators and harmful end-organ damage. Visceral leishmaniasis (VL)-induced HLH is a rare disease with significant diagnostic and management implications. Herein, we present a case of secondary HLH as a complication of visceral leishmaniasis in a two-year-old toddler. A 2-year-old male toddler was admitted for evaluation of a prolonged 4-week fever. Accompanying the fever, he developed progressive abdominal swelling, intermittent bilateral nasal bleeding, and repeated chest-focus infections of similar duration. The patient was acutely sick, with chronic signs of malnutrition (mid-upper arm circumference of 10.5 cm), fever (39 °C), tachypnea (70 breaths/min), tachycardia (132 beats/min), pallor, and hepatosplenomegaly. Initial investigation revealed leukopenia (2240/μl), anemia (7.3 g/dl), and severe thrombocytopenia (26,000/μl). With consideration of febrile neutropenia, the patient was started on cefepime with further revision to vancomycin and meropenem based on the culture result. After 10 days of persistent fever and poor clinical condition, an immunochromatographic rapid test with the rK39 antigen was conducted, and the patient was found to be positive for Leishmania spp. Intravenous liposomal amphotericin B (AmBisome) was initiated. On the 6th day of treatment, the patient's clinical and laboratory profiles severely deteriorated, and further laboratory investigation showed elevated triglyceride (524 mg/dl) and ferritin levels (1500 ng/mL). VL-induced secondary HLH was confirmed, and intravenous dexamethasone was initiated. Subsequently, his clinical and laboratory findings significantly improved, and he was discharged with PO dexamethasone. Our case highlights the intricate nature of VL-induced HLH and the need for high index of suspicion and timely management.

Clinicopathological characteristics, prognostic factors, and outcomes of elderly patients with lymphoma-associated hemophagocytic lymphohistiocytosis: A multicenter analysis

BACKGROUND

Lymphoma is the most common secondary cause of hemophagocytic lymphohistiocytosis (HLH) in adults. Lymphoma-associated HLH (LA-HLH) in the elderly population is not rare, however, little has been reported regarding clinicopathological characteristics, prognostic factors, and outcomes of LA-HLH in the elderly population.

METHODS

We retrospectively analyzed a multicenter cohort of elderly patients with LA-HLH. Clinicopathological features and treatment information were collected. The impacts of baseline characteristics and treatments on survival outcomes were analyzed.

RESULTS

A total of 173 elderly patients with LA-HLH were included. Compared with young patients, elderly patients showed different clinical and laboratory features. Regarding lymphoma subtypes, B-cell lymphoma was more common in elderly patients (elderly 61.3% vs. young 32.3%, p < 0.001) while T/NK-cell lymphoma was more common in young patients (65.3% vs. 35.3%, p < 0.001). The median survival of elderly patients with LA-HLH was only 92 days. The prior use of HLH therapy or etoposide-containing HLH therapy was not associated with improved overall survival. T/NK-cell subtype, a lower platelet count (≤53 × 109/L), a lower albumin level (≤32.1 g/L), a higher LDH level (>1407 U/L), and a higher creatinine level (>96.8 μmol/L) were independent predictors of decreased overall survival and 60-day survival. A prognostic index was established and demonstrated to be robust in predicting the overall survival and 60-day survival of elderly patients with LA-HLH.

CONCLUSIONS

LA-HLH in elderly patients displayed heterogeneous clinicopathological features and survival outcomes. Treatments need to be optimized to improve the outcomes of elderly patients with LA-HLH.

Hemophagocytic Lymphohistiocytosis Associated With T-cell Lymphoma in Pregnancy: Diagnostic Conundrum Unveiled

Hemophagocytic lymphohistiocytosis (HLH) during pregnancy is a rare and often misdiagnosed disease. The clinical manifestations are non-specific, contributing to a high maternal mortality rate. This case report details the presentation of a 31-year-old pregnant woman with high-grade fever initially treated as an infection-related condition. The diagnostic challenge arose from the rarity of HLH, its variable clinical presentation, and the lack of specificity in clinical and laboratory findings. Despite numerous tests and escalation of therapies, the patient, unfortunately, succumbed to HLH associated with T-cell lymphoma. This case report aims to raise awareness of HLH, emphasizing its challenging definition. Malignancy-associated HLH is not uncommon, and early identification and treatment are paramount to prevent progressive tissue damage, organ failure, and mortality. The atypical presentation of HLH as a clinical manifestation of T-cell lymphoma underscores the need for vigilance in diagnosing this potentially fatal syndrome.

Eighty-six cases of clinical characteristics and outcomes of systemic lupus erythematosus-associated macrophage activation syndrome: A meta-analysis study

OBJECTIVE

To improve our understanding of systemic lupus erythematosus (SLE)-macrophage activation syndrome (MAS).

METHODS

A systematic review was performed, to retrieve all those papers on patients with SLE-MAS, in individual or aggregated form. The data in each of these medical records were extracted and analyzed to identify the characteristics of SLE-MAS.

RESULTS

A total of 86 SLE-MAS patients were included (25 males and 61 females. The mean (±standard error of the mean) age was 31.21 ± 1.694 years. MAS occurred as the initial presentation of SLE in 47 people (54.65%) and during the course of SLE in 39 (45.35%). A coinfection was reported in 23 (26.74%) patients. The mean Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score was 16.54 ± 0.9462. Overall, 10 patients (11.63%) died. The SLEDAI-2K score was higher in patients with MAS as an initial manifestation of SLE than in those where MAS occurred during the course of SLE. The proportion of patients receiving steroid pulse therapy was lower in patients with coinfections. The deceased group demonstrated lower platelet and ferritin levels. Multiple regression analysis revealed that age and thrombocytopenia were independent factors associated with poor prognosis. In receiver operating characteristic analysis, a platelet count cutoff value of ≤47 × 109/L was a predictor of poor outcome.

CONCLUSIONS

SLE-MAS patients demonstrated high lupus activity, and lupus activity was especially higher in patients with MAS as an initial manifestation. Lupus activity was the predominant trigger of lupus MAS. Thrombocytopenia was an independent factor for poor prognosis.

Infection-associated hemophagocytic lymphohistiocytosis: a case report

Introduction

Hemophagocytic lymphohistiocytosis (HLH) is a rare hyperinflammatory disorder characterized by fever, cytopenia, splenomegaly, and hemophagocytosis. Without prompt treatment, HLH can rapidly progress to life-threatening multiorgan failure. The authors present a case of occult HLH with severe bicytopenia and organ dysfunction requiring intensive care.

Case presentation

A 20-year-old male presented with fever, cough, and constitutional symptoms. He developed hypoxia, elevated transaminases, and bicytopenia. Despite transfusions, platelet counts remained critically low. With high suspicion for HLH, head computed tomography and bone marrow biopsy was although panned but couldn't be performed due to resource less settings. And with suspicion for HLH treatment with high-dose dexamethasone was initiated as counts improved.

Clinical course

The patient required mechanical ventilation for pulmonary infiltrates. He exhibited seizure activity and epistaxis related to coagulopathy. On hospital day 9, he was successfully extubated as counts normalized. He was discharged from the intensive care unit once stable.

Conclusion

This case illustrates a delayed diagnosis of HLH masquerading as a fever of unknown origin. HLH should be urgently considered in patients with unexplained cytopenia, organ dysfunction, and systemic inflammation. Early treatment with immunotherapy can be lifesaving, whereas delays may precipitate irreversible end-organ damage.

Hemophagocytic Lymphohistiocytosis Triggered by Herpes Simplex Virus 1 and 2: A Narrative Review

Introduction: Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening syndrome characterized by an uncontrolled hyperinflammatory reaction. HLH is classified into primary (familial) and secondary (acquired). Secondary HLH is commonly triggered by infections, with viral infections being a leading cause. Its epidemiology and clinical features in cases associated with herpes simplex virus 1 and 2 remain underexplored. This study aimed to review all previously described cases of HSV-1 or -2-triggered HLH and provide information about this syndrome's epidemiology, microbiology, clinical characteristics, treatment, and outcomes. Methods: A narrative review was performed based on a search in PubMed, the Cochrane Library, and Scopus. Studies published until 27 April 2024 providing relevant data for HLH due to HSV 1 and 2 in humans were included. Results: We identified 29 eligible studies reporting HLH due to HSV 1 and 2, involving 34 patients. Half of them were adults, and half were neonates. Fever and splenomegaly were the most common clinical findings. Most patients were diagnosed with HSV-1 (64.7%), with PCR being the primary diagnostic method. The median duration of in-hospital treatment was 21 days, with acyclovir and steroids being the mainstays of therapy. The overall mortality rate was 41.2%, and AST levels emerged as an independent predictor of mortality. Conclusions: Our findings underscore the need for heightened awareness surrounding HLH triggered by HSV 1 and 2 and the importance of prompt diagnosis and tailored treatment approaches.

Practical approach to thrombocytopenia in patients with sepsis: a narrative review

Thrombocytopenia frequently occurs in patients with sepsis. Disseminated intravascular coagulation (DIC) may be a possible cause of thrombocytopenia owing to its high prevalence and association with poor outcomes; however, it is important to keep the presence of other diseases in mind in sepsis practice. Thrombotic microangiopathy (TMA), which is characterized by thrombotic thrombocytopenic purpura, Shiga toxin-producing Escherichia coli hemolytic uremic syndrome (HUS), and complement-mediated HUS, is characterized by thrombocytopenia, microangiopathic hemolytic anemia, and organ damage. TMA has become widely recognized in recent years because of the development of specific treatments. Previous studies have reported a remarkably lower prevalence of TMA than DIC; however, its epidemiology is not well defined, and there may be cases in which TMA is not correctly diagnosed, resulting in poor outcomes. Therefore, it is important to differentiate DIC from TMA. Nevertheless, differentiating between DIC and TMA remains a challenge as indicated by previous reports that most patients with TMA can be diagnosed as DIC using the universal coagulation scoring system. Several algorithms to differentiate sepsis-related DIC from TMA have been suggested, contributing to improving the care of septic patients with thrombocytopenia; however, it may be difficult to apply these algorithms to patients with coexisting DIC and TMA, which has recently been reported. This review describes the disease characteristics, including epidemiology, pathophysiology, and treatment, of DIC, TMA, and other diseases with thrombocytopenia and proposes a novel practical approach flow, which is characterized by the initiation of the diagnosis of TMA in parallel with the diagnosis of DIC. This practical flow also refers to the longitudinal diagnosis and treatment flow with TMA in mind and real clinical timeframes. In conclusion, we aim to widely disseminate the results of this review that emphasize the importance of incorporating consideration of TMA in the management of septic DIC. We anticipate that this practical new approach for the diagnostic and treatment flow will lead to the appropriate diagnosis and treatment of complex cases, improve patient outcomes, and generate new epidemiological evidence regarding TMA.

Secondary hemophagocytic lymphohistiocytosis triggered by Staphylococcus aureus bacteremia: A case report and systemic review

Adult haemophagocytic lymphohistiocytosis (HLH) is an infrequent and life-threatening condition. The most common triggers of HLH are malignancy and virus, and bacterial infections are rarely implicated. We present a case of HLH secondary to Staphylococcus aureus infection and systemically searched the PubMed database for publications on HLH associated with Staphylococcus aureus infection and reviewed nine cases from seven studies. A marked third of patients had infective endocarditis, while the mortality rate was 44 %. HLH developed in our case despite elimination of MRSA from the bloodstream, leading to eventual demise of our patient, suggesting that prolonged hyperimmune response may persist even after the elimination of initial triggering factor. Our case highlights the necessity of high clinical suspicion and prompt diagnosis of HLH.

A case report of hemophagocytic lymphohistiocytosis induced by toripalimab plus chemoradiotherapy in cervical cancer

Background

Hemophagocytic lymphohistiocytosis (HLH) is a rare but life-threatening clinical syndrome characterized by immune hyperactivation. Unlike primary HLH, immune checkpoint inhibitor (ICI)-triggered HLH is not well described, and there is a lack of theranostic guidelines. Herein, we first reported the successful management of PD-1 inhibitor-associated HLH in locally advanced cervical cancer.

Case presentation

We report a case of HLH in a 47-year-old patient with International Federation of Gynecology and Obstetrics (FIGO) IIIC1r cervical cancer who received toripalimab, a programmed cell death-1 receptor inhibitor, combined with chemoradiotherapy. The patient developed pyrexia, splenomegaly, leukopenia, anemia, thrombocytopenia, hypertriglyceridemia, hypofibrinogenemia, hyperferritinemia, reduced NK cell activity, elevated sCD25 levels, and hemophagocytosis in a bone marrow aspirate. Our patient was successfully treated with methylprednisolone, indicating that immune-induced HLH might respond to glucocorticoids, and is still alive with a complete response of the tumor.

Conclusion

Considering the possibility of HLH is needed in patients receiving ICIs to detect rare toxicities at an early stage when the patient develops uncontrollable fever, cytopenia, and splenomegaly, our multidisciplinary treatment modality contributed to the early diagnosis and successful management of HLH, avoiding progressive tissue damage and organ failure. Whether glucocorticoids are used alone or not for immune-associated HLH needs further investigation.

Nephrotoxicity in Bispecific Antibodies Recipients: Focus on T-Cell-Engaging Bispecific Antibodies

Recently, bispecific antibodies (BsAbs) are evolving the landscape of cancer treatment and have significantly improved the outcomes of relapsed or refractory cancer patients. As increasing BsAbs entered clinical practice, specific toxicities have emerged, and renal side-effects have been described. However, there are a lack of studies analyzing the nephrotoxicity in the anti-cancer BsAbs recipients systematically. In this review, we demonstrate the etiologies, mechanisms, other risk factors and treatment options of kidney injury in the BsAbs recipients to provide a more comprehensive insight into the nephrotoxicity post-BsAbs therapy. Significantly, due to the limited clinical trial data on each subject, we mainly conclude the related etiologies, mechanisms, and risk factors of nephrotoxicity that occur in T-cell-engaging BsAbs recipients. Nephrotoxicity associated with non-T-cell BsAbs may be associated with adverse nephrotoxicity of related monoclonal antibodies to two specific antigens. The aim of this paper is to provide nephrologists and oncologists with theoretical knowledge to provide better medical management for recipients who receive BsAbs, especially T-cell-engaging BsAbs treatment.

Tailoring the treatment of inflammatory rheumatic diseases by a better stratification and characterization of the clinical patient heterogeneity. Findings from a systematic literature review and experts' consensus

Inflammatory rheumatic diseases are different pathologic conditions associated with a deregulated immune response, codified along a spectrum of disorders, with autoinflammatory and autoimmune diseases as two-end phenotypes of this continuum. Despite pathogenic differences, inflammatory rheumatic diseases are commonly managed with a limited number of immunosuppressive drugs, sometimes with partial evidence or transferring physicians' knowledge in different patients. In addition, several randomized clinical trials, enrolling these patients, did not meet the primary pre-established outcomes and these findings could be linked to the underlying molecular diversities along the spectrum of inflammatory rheumatic disorders. In fact, the resulting patient heterogeneity may be driven by differences in underlying molecular pathology also resulting in variable responses to immunosuppressive drugs. Thus, the identification of different clinical subsets may possibly overcome the major obstacles that limit the development more effective therapeutic strategies for these patients with inflammatory rheumatic diseases. This clinical heterogeneity could require a diverse therapeutic management to improve patient outcomes and increase the frequency of clinical remission. Therefore, the importance of better patient stratification and characterization is increasingly pointed out according to the precision medicine principles, also suggesting a new approach for disease treatment. In fact, based on a better proposed patient profiling, clinicians could more appropriately balance the therapeutic management. On these bases, we synthetized and discussed the available literature about the patient profiling in regard to therapy in the context of inflammatory rheumatic diseases, mainly focusing on randomized clinical trials. We provided an overview of the importance of a better stratification and characterization of the clinical heterogeneity of patients with inflammatory rheumatic diseases identifying this point as crucial in improving the management of these patients.

Hemophagocytic Lymphohistiocytosis Unmasking Systemic Lupus Erythematosus: Management With Belimumab and a Case Study

Secondary hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory condition caused by the hyperactivation of macrophages and T-cells, triggered by infection, malignancy, or underlying rheumatological conditions. It rarely presents as a first manifestation of a rheumatological condition. Macrophage activation syndrome (MAS) is secondary HLH associated with underlying hematological conditions. Here, we present a case of a previously healthy 29-year-old female who was admitted with fever, rash, and pancytopenia, found to have HLH, and a workup revealed underlying systemic lupus erythematosus (SLE). She was successfully treated with dexamethasone, etoposide, and belimumab, with complete recovery of her symptoms. This case highlights the importance of a thorough evaluation of rheumatological conditions in all patients with HLH despite their previous medical history and the use of belimumab for SLE.

Infection-associated hemophagocytic lymphohistiocytosis: a case report

Introduction:

Hemophagocytic lymphohistiocytosis (HLH) is a rare hyperinflammatory disorder characterized by fever, cytopenia, splenomegaly, and hemophagocytosis. Without prompt treatment, HLH can rapidly progress to life-threatening multiorgan failure. The authors present a case of occult HLH with severe bicytopenia and organ dysfunction requiring intensive care.

Case presentation:

A 20-year-old male presented with fever, cough, and constitutional symptoms. He developed hypoxia, elevated transaminases, and bicytopenia. Despite transfusions, platelet counts remained critically low. With high suspicion for HLH, head computed tomography and bone marrow biopsy was although panned but couldn’t be performed due to resource less settings. And with suspicion for HLH treatment with high-dose dexamethasone was initiated as counts improved.

Clinical course:

The patient required mechanical ventilation for pulmonary infiltrates. He exhibited seizure activity and epistaxis related to coagulopathy. On hospital day 9, he was successfully extubated as counts normalized. He was discharged from the intensive care unit once stable.

Conclusion:

This case illustrates a delayed diagnosis of HLH masquerading as a fever of unknown origin. HLH should be urgently considered in patients with unexplained cytopenia, organ dysfunction, and systemic inflammation. Early treatment with immunotherapy can be lifesaving, whereas delays may precipitate irreversible end-organ damage.

Hemophagocytic lymphohistiocytosis associated with acute otitis media: A case report

INTRODUCTION

Hemophagocytic lymphohistiocytosis (HLH) is a potentially life-threatening syndrome for which early recognition and treatment are essential for improving outcomes. HLH is characterized by uncontrolled immune activation leading to fever, cytopenias, hepatosplenomegaly, coagulation abnormalities, and elevated typical markers. This condition can be genetic or secondary, with the latter often triggered by infections. Here, we present a unique case of HLH secondary to acute otitis media (AOM), a common ear infection.

PATIENT CONCERNS

We describe a 4-year-old boy who initially presented with a high fever and otalgia, later diagnosed with bilateral AOM. Despite antibiotic treatment, his condition deteriorated.

DIAGNOSIS

The patient fulfilled diagnostic criteria for HLH.

INTERVENTIONS

Aggressive treatment by using combination therapy with immunoglobulins, intravenous steroids (dexamethasone), cyclosporine, and etoposide was performed.

OUTCOMES

After 1 month of treatment, improvement in the otologic symptoms was observed, and hematological findings gradually improved and normalized.

LESSIONS

The link between AOM and HLH may be associated with inflammatory responses and immunological mechanisms, highlighting the importance of considering HLH in severe infection cases. This case emphasizes the need for prompt diagnosis and management, especially in secondary HLH scenarios, to improve patient outcomes. It is imperative to be aware of the potential correlation between these 2 conditions, and healthcare professionals should consider the likelihood of HLH.

[Hemophagocytic syndrome secondary to invasive NK cell leukemia and T-cell lymphoma treated with the modified MINE protocol: report of three cases and literature review]

Lymphoma-associated hemophagocytic syndrome is aggressive with rapid progression, particularly in NK/T cell lymphoma. The MINE regimen is a salvage treatment for aggressive non-Hodgkin lymphoma. In our center, the modified MINE regimen was applied to treat three patients with hemophagocytic syndrome secondary to aggressive NK cell leukemia and T-cell lymphoma. The modified MINE regimen showed good efficacy against NK/T cell lymphoma, control of the inflammatory state of secondary hemophagocytic syndrome, and good tolerability.

Hemophagocytic Lymphohistiocytosis: A Case Series From a Tertiary State Hospital in Malaysia and a Review of Current Literature

INTRODUCTION

Hemophagocytic lymphohistiocytosis (HLH) is a lethal emergency. Delays in diagnosis and treatment are detrimental to the health of patients. Classical clinical manifestations of HLH include fever, cytopenia, liver dysfunction, central nervous system involvement, and coagulopathy.

METHODS

We report seven cases of secondary HLH in adults diagnosed from a total of 1200 bone marrow aspiration and trephine biopsy (BMAT) examinations in our center, with various presentations and underlying triggers including infection, malignancy, and autoimmune disease.

RESULTS

HLH can present with non-specific signs and symptoms.

CONCLUSION

Early recognition of HLH is crucial to enable the commencement of therapy as early as possible to prevent mortality resulting from multi-organ failure.

Value of hemophagocytosis in the diagnosis of hemophagocytic lymphohistiocytosis in critically ill patients

BACKGROUND

Ferritin is an established biomarker in the diagnosis of secondary hemophagocytic lymphohistiocytosis (HLH), which is diagnosed by the HLH-2004 criteria. Among these criteria, detection of hemophagocytosis through invasive procedures may delay early life saving treatment. Our aim was to investigate the value of hemophagocytosis in diagnosing HLH in critically ill patients.

METHODS

In this secondary analysis of a retrospective observational study, we included all patients aged ≥18 years and admitted to any adult ICU at Charité-Universitätsmedizin Berlin between January 2006 and August 2018, who had hyperferritinemia (≥500 μg/L) and underwent bone marrow biopsy during their ICU course.

RESULTS

Two hundred fifty-two patients were included, of whom 31 (12.3%) showed hemophagocytosis. In multivariable logistic regression analysis, maximum ferritin was independently associated with hemophagocytosis. By removing hemophagocytosis from HLH-2004 criteria and HScore, prediction accuracy for HLH diagnosis was only marginally decreased compared to the original scores.

CONCLUSIONS

Our results strengthen the diagnostic value of ferritin and underline the importance of considering HLH diagnosis in patients with high ferritin but only four fulfilled HLH-2004 criteria, when hemophagocytosis was not assessed or not detectable. Proof of hemophagocytosis is not required for a reliable HLH diagnosis.

Population Pharmacokinetics of the Anti-Interferon-Gamma Monoclonal Antibody Emapalumab: An Updated Analysis

INTRODUCTION

Emapalumab is a fully human monoclonal antibody that targets free and receptor-bound interferon-gamma (IFNγ), neutralizing its biological activity. IFNγ levels differ by orders of magnitude between patients with primary hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS; a form of secondary HLH) in systemic juvenile idiopathic arthritis (sJIA). Therefore, this study aimed to develop a population pharmacokinetic model for emapalumab across a patient population with a wide range of total (free and emapalumab-bound) IFNγ levels using observations from patients with primary HLH or MAS in sJIA in clinical trials.

METHODS

Pharmacokinetic data were pooled (n = 58; 2709 observations) from studies enrolling patients administered emapalumab for primary HLH or MAS in sJIA. Patients with primary HLH were administered emapalumab 1 mg/kg (potentially increasing to 3, 6, and up to 10 mg/kg based on clinical response) every 3 days. Patients with MAS in sJIA were administered emapalumab 6 mg/kg, followed by 3 mg/kg every 3 days until day 15 and twice weekly until day 28. An earlier population PK model was re-parameterized using this data.

RESULTS

The final model for emapalumab comprised a 2-compartment model with first-order elimination. Emapalumab clearance remains constant when the total IFNγ concentration (free and emapalumab-bound) is < ~ 10,000 pg/ml but increases proportionally to total IFNγ concentration above this threshold. Emapalumab clearance was estimated to be 0.00218, 0.00308, 0.00623 and 0.01718 l/h at total serum IFNγ concentrations of 103, 104, 105 and 106 pg/ml, respectively, with corresponding terminal half-lives of 19.2, 13.8, 7.18 and 3.12 days for a 1-year-old patient weighing 10 kg with primary HLH. The median terminal half-life for emapalumab in patients with MAS in sJIA was estimated to be 24.0 (range, 6.13-32.4) days, which is similar to observations in healthy volunteers.

CONCLUSIONS

Emapalumab pharmacokinetics in patients with primary HLH and MAS in sJIA were described by a two-compartment model with fixed allometric exponents and an age-related effect. Differences in total IFNγ levels between patients with primary HLH and MAS may affect emapalumab pharmacokinetics, suggesting that each indication may require different dosing to rapidly control hyperinflammation.

TRIAL REGISTRATION

Clinicaltrials.gov identifiers: NCT01818492, NCT03311854 and NCT02069899.

Refractory insulin resistance and hemophagocytic lymphohistiocytosis following enfortumab vedotin treatment: A case report

The increasing incidence of urothelial carcinoma, coupled with advancements in its therapeutic landscape, has resulted in improved survival rates for patients. This, in turn, has led to a growing population of patients requiring specialized oncological care, with Enfortumab vedotin (EV) emerging as a pivotal treatment for metastatic urothelial carcinoma. While EV is associated with hyperglycemia, ketoacidosis is exceedingly rare. To the best of our knowledge, the link between EV and hemophagocytic lymphohistiocytosis (HLH) has not yet been explored. A 56-year-old patient diagnosed with metastatic urothelial carcinoma underwent EV treatment as a third-line treatment after progression following treatment with cisplatin/gemcitabine and pembrolizumab. Notably, after receiving two doses of EV, the patient exhibited refractory insulin resistance, leading to ketoacidosis. Subsequently, HLH emerged, necessitating a treatment regimen involving dexamethasone and etoposide. Despite intensive efforts, the patient experienced septic shock, resulting in death. The present case report highlights refractory insulin resistance and ketoacidosis, followed by reactive HLH, in the context of EV therapy. The limited literature on these complications demonstrates the need for further research to improve the understanding of the underlying mechanisms. With growing evidence of the efficacy of EV and evolving survival rates in urothelial carcinoma, healthcare professionals must remain vigilant for potential adverse effects, ensuring early recognition and optimal patient care.

Pathogenesis of Hemophagocytic Lymphohistiocytosis/Macrophage Activation Syndrome: A Case Report and Review of the Literature

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition characterized by the uncontrolled activation of cytotoxic T lymphocytes, NK cells, and macrophages, resulting in an overproduction of pro-inflammatory cytokines. A primary and a secondary form are distinguished depending on whether or not it is associated with hematologic, infectious, or immune-mediated disease. Clinical manifestations include fever, splenomegaly, neurological changes, coagulopathy, hepatic dysfunction, cytopenia, hypertriglyceridemia, hyperferritinemia, and hemophagocytosis. In adults, therapy, although aggressive, is often unsuccessful. We report the case of a 41-year-old man with no apparent history of previous disease and an acute onset characterized by fever, fatigue, and weight loss. The man was from Burkina Faso and had made trips to his home country in the previous five months. On admission, leukopenia, thrombocytopenia, increased creatinine and transaminases, LDH, and CRP with a normal ESR were found. The patient also presented with hypertriglyceridemia and hyperferritinemia. An infectious or autoimmune etiology was ruled out. A total body CT scan showed bilateral pleural effusion and hilar mesenterial, abdominal, and paratracheal lymphadenopathy. Lymphoproliferative disease with HLH complication was therefore suspected. High doses of glucocorticoids were then administered. A cytologic analysis of the pleural effusion showed anaplastic lymphoma cells and bone marrow aspirate showed hemophagocytosis. An Epstein-Barr Virus (EBV) DNA load of more than 90000 copies/mL was found. Bone marrow biopsy showed a marrow localization of peripheral T lymphoma. The course was rapidly progressive until the patient died. HLH is a rare but usually fatal complication in adults of hematologic, autoimmune, and malignant diseases. Very early diagnosis and treatment are critical but not always sufficient to save patients.