Hemophagocytic lymphohistiocytosis in adults: collaborative analysis of 137 cases of a nationwide German registry

A need for greater awareness: a mixed methods study of patient and healthcare professional perspectives on the diagnosis journey for haemophagocytic lymphohistiocytosis (HLH)

OBJECTIVES

Our aim was to better understand and raise awareness of the diagnosis journey and quantify any barriers for timely diagnosis of haemophagocytic lymphohistiocytosis (HLH), to support patients' struggle with diagnosis and reduce time to diagnosis.

METHODS

Patients diagnosed with, or caregivers for those diagnosed with primary or secondary HLH and physicians involved in the treatment of HLH were recruited. Quantitative interviews were undertaken with patients/caregivers to quantify key elements of the diagnosis journey, followed by qualitative interviews with participants. Interviews took place between March-May 2021.

RESULTS

Thirty-three patients/caregivers and nine physicians took part in this mixed methods study. Lack of physician awareness of HLH was a common frustration for patients/caregivers, causing delayed diagnosis. All physicians indicated bone-marrow testing is a key step in the diagnosis process, and some patients/caregivers had frustrations around testing. Emergency care doctors, although not usually involved in the diagnosis process, were among the most-seen specialists by patients/caregivers. Patients/caregivers suggested potential improvements in available information, such as providing information on treatment options and condition management.

DISCUSSION

Patients/caregivers and physicians agreed on the need to raise overall awareness of HLH signs/symptoms among priority groups of physicians to recognise how signs/symptoms can progress and develop. Improvements in the testing process and communication would directly impact the speed of diagnosis and support patients/caregivers during the diagnostic journey, respectively.

CONCLUSION

Raising awareness of key issues, such as signs/symptoms, tests and diagnostic procedures, and improved communication and support for patients/caregivers, are key to speeding up HLH diagnosis and improving outcomes.

Prevalence and mortality of haemophagocytic lymphohistiocytosis in dengue fever: a systematic review and meta-analysis

BACKGROUND

Haemophagocytic lymphohistiocytosis (HLH) is a rare complication of dengue fever with potentially life-threatening consequences and high mortality. Therefore, this study aims to investigate the prevalence, management and outcome of HLH in dengue fever.

METHODS

The major electronic databases, including PubMed, ScienceDirect and Ovid SP, were searched from inception until 31 January 2024 to identify relevant studies. Pooled prevalence and mortality were calculated using the random-effects generic inverse variance model with a 95% CI. All the statistical analysis was conducted using R programming.

RESULTS

A total of nine studies with 157 patients with HLH, 576 patients with severe dengue and 5081 patients with dengue fever were included in this meta-analysis. The prevalence of HLH in severe dengue (22.1%, 95% CI 8.07 to 48.0%) was significantly higher than the prevalence in dengue fever (3.12%, 95% CI 0.37 to 21.9%). The prevalence of HLH in severe dengue was higher in the paediatric population (22.8%, 95% CI 3.9 to 68.4%) compared with the adult population (19.0%, 95% CI 3.0 to 63.9%). The overall mortality rate was 20.2% (95% CI 9.7 to 37.2%).

CONCLUSION

The prevalence of dengue-associated HLH was low in patients with dengue fever but is significantly higher in patients with severe dengue and a high mortality rate.

Hemophagocytosis of the Hilar Pulmonary Lymph Nodes Is a More Sensitive Indicator of the Severity of COVID-19 Disease than Bone Marrow Hemophagocytosis

In systemic hyper-inflammation, as in severe COVID-19 disease, there are pronounced disorders of the hematological and lymphatic systems with prognostically relevant hemophagocytosis of the bone marrow. The current work aimed to address the importance of hemophagocytosis in the lymph nodes of patients with severe COVID-19 disease. From 28 patients who died of severe COVID-19 infection, samples of the vertebral bone marrow and lymph nodes from the cervical, hilar, para-aortic, mesenteric and inguinal locations were morphologically and immunohistologically (CD163, CD68, CD61, CD71, CD3, CD20, CD138) examined for the possible presence of hemophagocytosis. In the single-center study at the University Hospital Jena, a total of 191 hemophagocytes were found in the bone marrow and a total of 780 hemophagocytes in the lymph nodes in a standardized area of 21,924 mm2 per tissue sample. With 370 hemophagocytes, hilar lymph nodes were most frequently affected (370/780; 47.44%; 95%-CI: [43.94, 50.95]), followed by cervical lymph nodes (206/780; 26.41%; 95%-CI: [23.41, 29.59]), para-aortic lymph nodes (125/780; 16.03%; 95%-CI: [13.58, 18.73]) and inguinal/mesenteric lymph nodes (79/780; 10.13%; 95%-CI: [8.155, 12.4]). Based on the standard area (21,924 mm2), the difference in the number of hemophagocytes in the bone marrow and in the hilar lymph nodes was statistically significant (p < 0.05), while this did not apply to the lymph nodes from the other locations. In fatal COVID-19 disease, hemophagocytosis is particularly found in the hilar lymph nodes and is therefore a better indicator of the severity of the disease than hemophagocytosis in the bone marrow. The findings provide some evidence for the concept of compartmentalized human host responses to life-threatening infections.

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.

Acute Hemophagocytic Lymphohistiocytosis Due to Tularemia

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening disorder marked by excessive immune system activation. Diagnosing HLH is particularly difficult due to its diverse etiology and similar clinical presentation. Patients with HLH often require intensive critical care. The condition is divided into HLH syndrome (genetic defects) and HLH disease, and both can be triggered by factors such as infections, autoimmune diseases, or malignancies. We present here the first documented case of acute HLH secondary to tularemia with septic shock in a 62-year-old female. Initially suspected due to malignancy-induced acute HLH, she was treated with etoposide and dexamethasone and was immediately transitioned to antimicrobials once she was confirmed positive for Francisella tularemia on blood cultures at the state microbiology laboratory. She had a prolonged clinical course of 31 days, followed by an excellent recovery after treatment with antimicrobials. This case highlights the importance of recognizing tularemia as a potential cause of HLH. Identifying and addressing the causative agent promptly is crucial for effective management and treatment of HLH.

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.

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.

Clinical and Biochemical Characteristics of Hemophagocytic Lymphohistiocytosis in People Living With HIV and Disseminated Histoplasmosis at a Tertiary Hospital in Mexico

Background

Hemophagocytic lymphohistiocytosis (HLH) is considered a rare disease with high morbidity and mortality risks. Most research on this disease is conducted in pediatric settings. Therefore, this study aimed to describe the clinical characteristics, laboratory findings, and outcomes related to HLH in people living with human immunodeficiency virus (HIV)/AIDS) and disseminated histoplasmosis.

Methods

A retrospective and descriptive study was conducted in a tertiary hospital in México City from January 2018 to December 2022, including people living with HIV who had disseminated histoplasmosis confirmed through direct microbiological or immunological methods with an HScore ≥169 or who met 5 of the 8 HLH-2004 criteria.

Results

HLH occurred in 36.1% (n = 26) of patients with HIV and disseminated histoplasmosis; the majority were men (84.9%), and their mean age (standard deviation) was 30.19 (5.6) years. The most frequent clinical manifestations were hepatomegaly (100%), fever (96.2%), and dyspnea (84.6%). The most common biochemical changes were hyperferritinemia (100%), elevated lactate dehydrogenase (100%), and bicytopenia (61.5%). Partial thromboplastin time (P = .012) and prothrombin time (P = .004) were associated with the 30-day mortality rate, and the 30-day survival rate was 65.4%.

Conclusions

We detected a high frequency of HLH; therefore, we encourage physicians to use diagnostic prediction tools (HLH-2004 and HScore criteria) in each reassessment for timely detection.

Reactive hemophagocytic lymphohistiocytosis: Epidemiological, clinico-biological and etiological profile

Hemophagocytic lymphohistiocytosis (HLH) is an hyperinflammatory state resulting from increased secretion of proinflammatory cytokines, which are responsible for clinical, biological and cytological manifestations.

OBJECTIVE

The aim of our study is to describe the epidemiological, clinical, biological, etiological and evolutionary profile of HLH in Tunisia.

METHODS

A retrospective study that involved patients, with images of hemophagocytosis in myelograms analyzed at the laboratory of biological hematology of the University Hospital "Hédi-Chaker" of Sfax-Tunisia, followed at these departments: hematology, internal medicine, department of infectious-diseases and department of gastroenterology, (June2017- May2021). First, we identified all patients with hemophagocytosis images. Secondly, we selected the patients who fulfilled the diagnostic criteria of the HLH-2004-score.

RESULTS

Nineteen patients were included in this study. Nine men and 10 women with a mean age of 37.95 years. Fever was present in all patients. Organomegaly was described in 74% of cases. The most frequent cytopenia was anemia (100%). Hypertriglyceridemia was noted in 79% of cases and hyperferritinemia (> 500 ng/mL) was ubiquitous. In myelogram, 68% of patients had slides showing numerous or very numerous images of hemophagocytosis. The infectious pathology was the most common cause of HLH (42%). No cause was found in 10% of cases. The corticosteroid therapy at a dose of 1 mg/kg/day was prescribed in 89% of our patients. The overall evolution was favorable in 58% of cases. The mortality was not associated with the causal pathology (p=0.218).

CONCLUSION

Secondary HLH is likely to be under-recognized, which contributes to its high morbidity and mortality. Early recognition is crucial for any reasonable attempt at curative therapy.

[Hemophagocytic lymphohistiocytosis and macrophage activation syndrome : A multidisciplinary challenge]

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome that is characterized by hyperferritinemia, cytopenia, disseminated intravascular coagulopathy and functional disorders of the liver and the central nervous system. The term macrophage activation syndrome is predominantly used for secondary HLH in the context of autoimmune diseases (e.g., systemic juvenile idiopathic arthritis). In addition, malignancies and genetic inborn errors of immunity can predispose to the development of HLH. Infections (e.g., Epstein-Barr virus) in turn represent possible triggers of an acute episode. Due to the unspecific manifestation of the disease, a systematic evaluation of the organ systems is recommended in the clinical and laboratory analytical clarification of hyperinflammatory syndromes. In general, the treatment should be carried out by a multidisciplinary team with expertise in rheumatology, hematological oncology, infectious diseases and intensive care medicine. The primary treatment of HLH usually consists of glucocorticoids and in cases of a rapid deterioration of the condition anakinra (interleukin 1 block) and intravenous immunoglobulins can be employed. Treatment of the underlying disease should be consequently carried out in parallel, together with antimicrobial treatment.

A Case Report of Pregnancy Complicated with Primary Hemophagocytic Lymphohistiocytosis

Background

Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory syndrome characterized by excessive activation of NK cells and cytotoxic T lymphocytes, subsequently leading to macrophage activation and increased cytokine production. Misdiagnosis due to nonspecific clinical presentations and inadequate understanding of the disease can significantly jeopardize the safety of both the mother and the infant. We report a case of pregnancy combined with HLH and conduct a literature review to provide insights into the diagnosis and treatment of pregnancy-related HLH.

Case Presentation

We discussed a case of a pregnant woman with persistent postpartum fever, serum ferritin, and elevated liver function, who failed to respond to repeated anti-infective therapy and was diagnosed with HLH after multidisciplinary diagnostic treatment. We gave dexamethasone treatment, and the patient's temperature and blood cells quickly returned to normal. Finally, exome sequencing revealed heterozygous variation in UNC13D gene, so we considered this case as pregnancy combined with primary HLH (pHLH).

Conclusion

We report the case of HLH diagnosed during pregnancy and show that early diagnosis and timely intervention can prevent rapid disease progression, reduce maternal mortality rates, and improve survival rates. Additionally, molecular genetic testing can confirm pathogenic gene mutations, providing essential genetic counseling for patients with pHLH who plan to conceive a healthy child.

Early hematopoietic cell transplantation for familial hemophagocytic lymphohistiocytosis in a regional treatment network in Japan

Familial hemophagocytic lymphohistiocytosis (FHLH) is a fatal hyperinflammation syndrome arising from the genetic defect of perforin-mediated cytolysis. Curative hematopoietic cell transplantation (HCT) is needed before development of central nervous system (CNS) disease. We studied treatment outcomes of 13 patients (FHLH2 n = 11, FHLH3 n = 2) consecutively diagnosed from 2011 to 2022 by flow cytometric screening for non-myeloablative HCT in a regional treatment network in Kyushu, Japan. One patient with a novel PRF1 variant escaped screening, but all patients with FHLH2 reached diagnosis and 8 of them received HCT until 3 and 9 months of age, respectively. The earliest HCT was conducted 65 days after birth. Three pretransplant deaths occurred in newborns with liver failure at diagnosis. Ten posttransplant patients have remained disease-free, 7 of whom had no neurological involvement. Time from first etoposide infusion to HCT was shorter in patients without CNS disease or bleeding than in patients with those factors (median [range] days: 62 [50-81] vs. 122 [89-209], p = 0.016). Six of 9 unrelated patients had a PRF1 c.1090_1091delCT variant. These results suggest that the critical times to start etoposide and HCT are within 3 months after birth and during etoposide control, respectively. Newborn screening may increase the percentage of disease-free survivors without complications.

Secondary hemophagocytic syndrome in an acquired immunodeficiency syndrome and Alpha-thalassemia patient infected with Talaromyces marneffei: A case report and literature review

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease characterized by a hyperinflammatory syndrome and impairment of multiple organ systems. Talaromycosis marneffei (TSM) is an opportunistic infection mostly found in immunosuppressed populations, such as those with acquired immunodeficiency syndrome (AIDS), and is prevalent in southern China. However, HLH secondary to TSM is extremely rare and has only been reported in isolated cases. A 30-year-old patient with recurrent high fever and progressive cytopenia was diagnosed with HLH secondary to disseminated TSM with AIDS and Alpha-thalassemia. The patient remained in sustained remission without recurrence after effective treatment with antifungals and glucocorticoids.

Persistent Fever after COVID-19 Vaccination in a Patient with Ulcerative Colitis: A Call for Attention

The development of vaccinations has been game-changing in the ongoing effort to combat the COVID-19 pandemic. Until now, adverse effects are being reported at low frequency, including thrombocytopenia and myocarditis. Careful monitoring for any suspicious symptoms and signs following vaccination is necessary. We report a case of hemophagocytic lymphohistiocytosis (HLH) after mRNA COVID-19 vaccine in a 23-year-old female with ulcerative colitis. Diagnosis was made according to HLH-2004 criteria and the patient was treated with dexamethasone with response. Our report aimed to draw attention to the potential relation between COVID-19 vaccines and HLH and the necessity of continued surveillance, especially in at-risk populations such as those with underlying immune dysregulation.

Hemophagocytic lymphohistiocytosis during treatment of intracranial multifocal germinoma: a case report and literature review

Hemophagocytic lymphohistiocytosis (HLH), also known as hemophagocytic syndrome (HPS), is a benign histiocytosis with hyperreactive proliferation of the mononuclear phagocyte system caused by immune function abnormalities, which often occurs under the background of genetic mutations, inflammation, infection or tumors. Because the research on malignancy-associated HLH (M-HLH) is focused on hematological malignancies, reports on HLH secondary to solid tumors are rare. In this case, we report a 14-year-old girl who developed HLH during treatment for intracranial multifocal germinoma, and the disease was controlled after hormone combined with etoposide(VP-16) and other related treatments. To our knowledge, there have been no documented cases of HLH caused by intracranial multifocal germinoma.

Rubella virus chronic inflammatory disease and other unusual viral phenotypes in inborn errors of immunity

Infectious susceptibility is a component of many inborn errors of immunity. Nevertheless, antibiotic use is often used as a surrogate in history taking for infectious susceptibility, thereby disadvantaging patients who present with viral infections as their phenotype. Further complicating clinical evaluations are unusual manifestations of viral infections which may be less familiar that the typical respiratory viral infections. This review covers several unusual viral phenotypes arising in patients with inborn errors of immunity and other settings of immune compromise. In some cases, chronic infections lead to oncogenesis or tumor-like growths and the conditions and mechanisms of viral-induced oncogenesis will be described. This review covers enterovirus, rubella, measles, papillomavirus, and parvovirus B19. It does not cover EBV and hemophagocytic lymphohistiocytosis nor lymphomagenesis related to EBV. EBV susceptibility has been recently reviewed. Our goal is to increase awareness of the unusual manifestations of viral infections in patients with IEI and to describe treatment modalities utilized in this setting. Coincidentally, each of the discussed viral infections can have a cutaneous component and figures will serve as a reminder of the physical features of these viruses. Given the high morbidity and mortality, early recognition can only improve outcomes.

CORONAVIRUS SARS-COV-2 MODIFIES ANTITUMOR REDOX STATUS OF BLOOD AND INTERCELLULAR MATRIX IN METASTATIC COLORECTAL CANCER PATIENTS (A PILOT STUDY)

BACKGROUND

The current studies demonstrate that SARS-CoV-2 infection results in increasing complications incidence and the total risk of death in cancer patients. SARS-CoV-2 infection triggers oxidative stress representing one of the major factors of the inflammation contributing to the complicated course of the diseases including cancer.

AIM

To assess the effect of hypoxia caused by SARS-CoV-2 infection on the redox status of blood in patients with metastatic colorectal cancer (mCRC).

MATERIALS AND METHODS

10 patients with SARS-CoV-2, 11 mCRC patients with metachronous liver disease, and 14 mCRC patients with preceding SARS-CoV-2 infection were included in the study. The data on blood biochemistry (C-reactive protein, ferritin, transferrin, and free iron) were analyzed. The levels of superoxide radicals (ROS) in blood cells were determined by electron paramagnetic resonance (EPR) using the spin trap technique. The metalloproteinase activity was measured by polyacrylamide gel zymography with the addition of gelatin as a substrate.

RESULTS

In mCRC patients with prior SARS-CoV-2 infection, a 1.26-fold increase in ROS-generating activity of blood neutrophils was observed compared to mCRC patients with no history of SARS-CoV-2 infection. The blood content of C-reactive protein, transferrin, and free iron in mCRC patients with prior SARS-CoV-2 infection increased by 2, 6, and 1.4 times, respectively. The total activity of gelatinases in platelets and neutrophils in the blood of mCRC patients with prior SARS-CoV-2 infection was 1.4 and 1.2 times higher compared to mCRC patients with no history of SARS-CoV-2 infection.

CONCLUSION

mCRC patients with prior COVID-19 have a higher risk of exacerbation of inflammatory reactions. SARS-CoV-2 infection results in redox dіsbalance, which may contribute to the unfavorable course of the disease.

Patients with Hemophagocytic Lymphohistiocytosis Who Need Intensive Care Can Be Successfully Rescued by Timely Using Etoposide-Based HLH Regimens

Background

Hemophagocytic lymphohistiocytosis (HLH) patients who need intensive care usually have multiple organ failure and poor prognosis. However, the clinical characteristics, therapeutic efficacy and outcome in these critically ill HLH patients have remained unclear.

Methods

We performed a retrospective study of 50 critically ill HLH patients from September 2013 to October 2022. Patients' information was collected, and the overall survival rate was estimated.

Results

Fifty HLH patients need intensive care, and the median sequential organ failure assessment (SOFA) score was 8. 66.00% patients had septic shock, 60.00% had disseminated intravascular coagulation (DIC) and 56.00% had acute respiratory distress syndrome (ARDS). 64.00% patients needed vasoactive drugs, 60.00% needed invasive or non-invasive positive pressure mechanical ventilation, and 12.00% needed continuous renal replacement therapy (CRRT). Among 18 patients received the etoposide-based regimens, the median time for 17 patients to remove ECG monitoring was 13 days (4-30 days); the median time to remove respiratory support in 10 patients was 8.5 days (4-21 days); the median time for 5 patient to convert from dominant DIC to non-dominant DIC was 4 days (1-14 days) and the median time for 6 patients to stop using vasoactive drugs was 10 days (2-14 days). After 4 weeks of treatment, 7 patients were evaluated as NR, 6 achieved PR, and 5 could not be evaluated. The ORR was 55.56%. Up to the last follow-up, the OS rate of patients receiving etoposide-based regimens was 66.67%. In contrast, all 32 HLH patients in other groups died. Univariate analysis showed that PCT > 0.5 ug/L, PT prolonged > 6 s, TBil > 25umol/L, respiratory failure, renal failure, liver failure and did not receive etoposide- based regimens were the negative factors affecting survival (P = 0.001, 0.017, 0.043, 0.001, 0.000, 0.029, 0.000).

Conclusion

HLH patients who need intensive care timely used etoposide-based HLH regimens might rescue critically ill patients successfully.

Lymphoma-associated hemophagocytic lymphohistiocytosis (LA-HLH): a scoping review unveils clinical and diagnostic patterns of a lymphoma subgroup with poor prognosis

Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory syndrome driven by pathologic activation of cytotoxic T-lymphocytes and macrophages. Despite advances in diagnostics and management, adult patients with lymphoma-associated HLH (LA-HLH) harbor particularly poor prognosis and optimal treatment remains challenging. As systematic data on LA-HLH are scarce, we aimed to synthesize research evidence by thorough analysis of the published literature in PubMed (MEDLINE-database) within the context of a scoping review. Of 595 search results, 132 articles providing information on 542 patients were reviewed and analyzed. Median patient age was 60 years (range, 18-98) with male predominance (62.7%). B- and T-NHL were equally represented (45.6% and 45.2%), Hodgkin's lymphoma was reported in 8.9% of the cases. The majority of patients (91.6%) presented in Ann-Arbor-Stages III and IV, and bone marrow infiltration was observed in a significant proportion of patients (61.5%). Soluble CD25 levels were markedly elevated (median 10,000 U/ml), with levels beyond 10,000 U/ml indicating unfavorable prognosis for 30-day and overall survival. 66.8% of the patients died after median 5.1 months. LA-HLH remains a clinical challenge requiring specialized management. Timely diagnosis and appropriate lymphoma-specific treatment are of utmost importance to enhance patient outcomes.

Prognostic Factors of Adult Hemophagocytic Lymphohistiocytosis and Clinical Utility of HLH-2004 Diagnostic Criteria and HScore: A Real-World Multicenter Study from Thailand

INTRODUCTION

Adult hemophagocytic lymphohistiocytosis (HLH) is a rare disease with a dismal prognosis. Early diagnosis and prompt management are necessary for improved outcomes.

METHODS

This multicenter retrospective study investigated the etiologies, survival, and prognostic factors of HLH, including the utility of HLH-2004 criteria and HScore in real-life clinical practice.

RESULTS

A total of 147 HLH patients were identified by using a combination of hemophagocytosis identification in bone marrow and the HLH-related international classification disease-10. A total of 116 (78.9%) patients fulfilled the HLH diagnosis by HScore, while 91 (61.9%) patients fulfilled 5 of 8 HLH-2004 criteria. In Thailand, the clinical application of HLH-2004 criteria needed to be reduced from 8 to 6 due to a lack of sCD25 and natural killer cell activity tests. Using the adapted HLH-2004 with a cutoff value of 4 resulted in 132 (89.9%) cases meeting the diagnostic criteria. Among these 132 confirmed HLH patients by using adapted HLH-2004, HLH was triggered by infection (29.5%), autoimmune disease (12.9%), malignancy (40.9%), and unknown cause (16.7%). Median overall survival of HLH patients was extremely short (67 days). Ferritin >6,000 μg/L, HLH from infection, malignancy, and unknown etiology were demonstrated as independent prognostic factors for inferior survival (hazard ratio [HR] 2.47; 95% confidence interval [CI] 1.39-4.37, HR 4.69; 95% CI 1.38-15.92, HR 6.09; 95% CI 1.84-20.14, and HR 6.02; 95% CI 1.64-22.05, respectively).

CONCLUSION

Ferritin is a helpful biomarker for HLH diagnosis and prognostic prediction. Autoimmune disease-triggered HLH has favorable outcomes. Future prospective study is required to verify the use of the adapted HLH-2004 criteria.

Erythrophagocytosis is not a reproducible finding in liver biopsies, and is not associated with clinical diagnosis of hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a rare disease with high mortality. Liver involvement is common (based on elevated liver function tests) with most patients demonstrating acute hepatitis. Liver biopsies are frequently obtained in the setting of suspected HLH for the purpose of identification of erythrophagocytosis, and if present, this finding is thought to suggest or support the diagnosis of HLH. However, there are problems with this approach; in particular, we do not know whether this finding is reproducible or whether it is specific to HLH. Therefore, we conducted a multi-institutional study in which experienced liver pathologists reviewed images taken from liver biopsies from patients with normal liver, acute hepatitis, possible HLH, and clinical HLH to determine if there was agreement about the presence or absence of erythrophagocytosis, and to ascertain whether the finding corresponds to a clinical diagnosis of HLH. Twelve liver pathologists reviewed 141 images in isolation (i.e., no clinical information or diagnosis provided). These came from 32 patients (five normal, 17 acute hepatitis, six HLH, four possible HLH). The pathologists classified each image as negative, equivocal, or positive for erythrophagocytosis. Kappa was .08 (no agreement) for case-level and 0.1 for image-level (1.4% agreement, based on two images which were universally considered negative). There was no difference in the proportion of pathologists who diagnosed erythrophagocytosis among those with different diagnoses at case or image-level (p = 0.82 and p = 0.82, respectively). Thus, erythrophagocytosis is an entirely unreliable histologic parameter in liver, as it is irreproducible and not demonstrably associated with a clinical disease (namely, HLH). Unless and until more reliable guidelines can be established, pathologists should refrain from commenting on the presence or absence of erythrophagocytosis in liver biopsy.

Diagnosis and investigation of suspected haemophagocytic lymphohistiocytosis in adults: 2023 Hyperinflammation and HLH Across Speciality Collaboration (HiHASC) consensus guideline

Haemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome characterised by persistently activated cytotoxic lymphocytes and macrophages, which, if untreated, leads to multiorgan dysfunction and death. HLH should be considered in any acutely unwell patient not responding to treatment as expected, with prompt assessment to look for what we term the three Fs-fever, falling blood counts, and raised ferritin. Worldwide, awareness of HLH and access to expert management remain inequitable. Terminology is not standardised, classification criteria are validated in specific patient groups only, and some guidelines rely on specialised and somewhat inaccessible tests. The consensus guideline described in this Health Policy was produced by a self-nominated working group from the UK network Hyperinflammation and HLH Across Speciality Collaboration (HiHASC), a multidisciplinary group of clinicians experienced in managing people with HLH. Combining literature review and experience gained from looking after patients with HLH, it provides a practical, structured approach for all health-care teams managing adult (>16 years) patients with possible HLH. The focus is on early recognition and diagnosis of HLH and parallel identification of the underlying cause. To ensure wide applicability, the use of inexpensive, readily available tests is prioritised, but the role of specialist investigations and their interpretation is also addressed.

Clinical characteristics of hemophagocytic lymphohistiocytosis

BACKGROUND

There is no specificity in the clinical presentation of hemophagocytic lymphohistiocytosis (HLH).

OBJECTIVE

To study some clinical, etiological, and prognostic features of HLH to improve the clinical understanding of the disease.

METHODS

Retrospective analysis of the clinical data of 125 patients with HLH admitted to our hospital from June 2015 to August 2021, including clinical characteristics, laboratory indicators, and survival period. Statistical analysis was performed from the overall group of study indicators, which included population, children, and adults.

RESULTS

In the whole population, sex, age, blood myoglobin, and NK cell ratio of M-HLH and non-M-HLH patients (P< 0.05), serum albumin, and direct bilirubin were independent correlates of M-HLH. In the pediatric group, age and the proportion of NK cells were significantly different between M-HLH and non-M-HLH patients (P< 0.05). Multivariate Logistic regression analysis showed that all factors were not significantly associated with M-HLH. The associated regression analysis showed that all factors were not significantly associated with M-HLH. ROC curve analysis showed that the best predictive value of NK cell percentage for M-HLH diagnosis in the overall population was 4.96% in the pediatric group and 4.96% in the adult group. The best predictive value for M-HLH diagnosis was 2.08%. The univariate analysis showed that platelet count, alanine aminotransferase, aspartate aminotransferase, serum albumin, direct bilirubin and indirect bilirubin affected prognosis; COX regression showed that none of these factors had a significant relationship. The overall median survival time was 20.7 months in the adult group, 44.3 months in non-M-HLH patients, and 7.73 months in M-HLH patients (p= 0.011); univariate analysis showed that platelet count and serum albumin level affected prognosis; COX regression results in serum albumin level was an independent risk factor for prognosis.

CONCLUSION

The survival rate of non-M-HLH was significantly better than that of M-HLH; the proportion of NK cells had predictive value for the diagnosis of M-HLH; in the general population, non-M-HLH was more likely to have abnormal liver function than M-HLH: lower platelet count and serum albumin level were associated with poor prognosis, and the lower the platelet count and serum albumin level, the worse the prognosis: in addition, adults with lower serum albumin levels are also associated with poor prognosis.

Hemophagocytic lymphohistiocytosis with jaundice as first manifestation: A case report

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare but life-threatening condition. It is an immune-mediated disease that has a wide range of causes, elicits a hyperinflammatory response, and results in multiple organ damage. Clinical presentations vary, and in some cases, jaundice occurs as the first symptom.

CASE SUMMARY

We report the case of a 71-year-old female patient who presented with jaundice. She was admitted to our hospital because of the occurrence of "jaundice for half a month", and upon examination, obstructive jaundice with choledocholithiasis and gallstones was suggested. Cholecystectomy and choledocholithotomy were performed. However, the jaundice did not improve after surgery. We found splenomegaly, cytopenia, hypertriglyceridemia, hypofibrinogenemia, and elevated ferritin. Bone marrow biopsy revealed hemophagocytosis. Later, cardiac arrest occurred when she returned 3 wk after the surgery. We considered that HLH was triggered by septic shock. The patient's condition deteriorated rapidly, with multiple organ dysfunction and severe gastrointestinal bleeding. Corticosteroid therapy and symptomatic treatment failed to save her life.

CONCLUSION

Jaundice rarely presents as the first symptom in HLH patients. The HLH in this case was triggered by septic shock with jaundice as the first symptom. Clinicians should try hard to reduce missed diagnoses and misdiagnoses.

Hemophagocytic lymphohistiocytosis with a hemizygous PRF1 c.674G>A mutation

Hemophagocytic lymphohistiocytosis(HLH) is a rare highly-fatal disease presenting with fever, hepatosplenomegaly, and pancytopenia and has a poor prognosis. Homozygous or semi-zygous or complex heterozygous variants can cause familial HLH and heterozygous carriers are frequently seen in secondary HLH. A 42-year-old male patient was admitted to the hospital for persistent fever, fatigue, and splenomegaly. Investigations revealed hypertriglyceridemia, hyperlactatemia dehydrogenaseemia, hyperferritinemia, and elevated levels of soluble cluster of differentiation 25. We found a heterozygous mutation of PRF1: c.674G>A (p.R225Q) through next-generation sequencing technology of hemophagocytic-lymphohistiocytosis-related genes. After a brief remission with dexamethasone and etoposide-based therapy, the disease relapsed quickly, and an allogeneic hematopoietic stem cell transplant was performed to achieve complete remission. To date, the patient's condition was in complete remission. Our study detected a rare missense mutation in the PRF1 gene in a patient with HLH disease and the c.674G>A mutation may be rated as a possible pathogenic variant.

[Diagnostics and treatment of hemophagocytic lymphohistiocytosis]

Hemophagocytic lymphohistiocytosis (HLH) is a hyperferritinemic hyperinflammatory syndrome. A primary hereditary form can be distinguished from a secondary acquired form. In adults the secondary form accounts for the vast majority of cases. Infections, malignancies and autoimmune disorders are common triggering factors of secondary HLH. Persistent fever, bicytopenia or pancytopenia and splenomegaly represent major symptoms in HLH and occur in virtually all patients. The diagnosis of HLH is made on the basis of the HLH-2004 criteria. The probability of the presence of HLH can be estimated using the HScore. Patients with HLH require immunosuppressive treatment. Hence, high doses of corticosteroids represent the cornerstone of treatment. Furthermore, immunoglobulins, anakinra, ruxolitinib or etoposide are given depending on the triggering factor. The course and prognosis of HLH are dependent on the early initiation of treatment, the triggering factor and the response to treatment.

Delay in treatment of adult hemophagocytic lymphohistiocytosis is associated with worse in-hospital outcomes

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition characterized by uncontrolled activation of the immune system leading to multiorgan failure. Timely initiation of HLH-specific treatment is believed to be essential and lifesaving. Due to the rarity of the condition in adults, there is no data available in the literature to investigate the effects of treatment delay in this age group. We used data from the National Inpatient Sample (NIS) to evaluate the inpatient practices of HLH treatment initiation over 13 years (2007-2019) and their association with clinically relevant inpatient outcomes. Patients were divided into early treatment group (<6 days) and late treatment group (≥ 6 days). We compared outcomes using multivariate logistic regression models adjusting for age, sex, race, and HLH-triggering conditions. There were 1327 and 1382 hospitalizations in the early and late treatment groups, respectively. Hospitalization in the late treatment group had higher rates of in-hospital mortality (OR 2.00 [1.65-2.43]), circulatory shock (OR 1.33 [1.09-1.63]), requiring mechanical ventilation (OR 1.41 [1.18-1.69]), venous thromboembolism (OR 1.70 [1.27-2.26]), infectious complications (OR 2.24 [1.90-2.64]), acute kidney injury (OR 2.27 [1.92-2.68]), and requiring new hemodialysis (OR 1.45 [1.17-1.81]). Additionally, we observed no significant trend in the mean time to treatment over the study period. This study shows the importance of early initiation of HLH treatment and highlights the adverse outcomes of treatment delay.

Hypofibrinogenemia is an independent predictor of hemophagocytic lymphohistiocytosis in children with sepsis

Hemophagocytic lymphohistiocytosis (HLH) is a potentially life-threatening condition in children with sepsis. We herein aimed to identify clinical and laboratory predictors of HLH in children with sepsis. We conducted a retrospective study of 568 children with sepsis admitted to Guangdong Women and Children Hospital from January 2019 to June 2022. HLH, while rare (6.34%), proved to be a highly fatal complication (37.14%) in children with sepsis. Children with HLH had higher levels of aspartate aminotransferase, lactate dehydrogenase, triglycerides, and ferritin than children without HLH; conversely, they displayed decreased levels of neutrophils, hemoglobin, platelets, fibrinogen, and albumin. Additionally, the HLH group showed higher rates of prolonged fever (> 10 days), hepatomegaly, and splenomegaly than the non-HLH group. Our retrospective analysis identified hypofibrinogenemia (OR = 0.440, P = 0.024) as an independent predictor for the development of HLH in patients with sepsis. The optimal cutoff value for fibrinogen was found to be < 2.43 g/L. The area under the curve for diagnosing HLH was 0.80 (95% confidence interval: 0.73-0.87, P < 0.0001), with a sensitivity of 72.41% and specificity of 76.27%. Thus, hypofibrinogenemia emerges as a potentially valuable predictor for HLH in children with sepsis.

The 2022 EULAR/ACR Points to Consider at the Early Stages of Diagnosis and Management of Suspected Haemophagocytic Lymphohistiocytosis/Macrophage Activation Syndrome (HLH/MAS)

OBJECTIVE

Haemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are life-threatening systemic hyperinflammatory syndromes that can develop in most inflammatory contexts. They can progress rapidly, and early identification and management are critical for preventing organ failure and mortality. This effort aimed to develop evidence-based and consensus-based points to consider to assist clinicians in optimising decision-making in the early stages of diagnosis, treatment and monitoring of HLH/MAS.

METHODS

A multinational, multidisciplinary task force of physician experts, including adult and paediatric rheumatologists, haematologist/oncologists, immunologists, infectious disease specialists, intensivists, allied healthcare professionals and patients/parents, formulated relevant research questions and conducted a systematic literature review (SLR). Delphi methodology, informed by SLR results and questionnaires of experts, was used to generate statements aimed at assisting early decision-making and optimising the initial care of patients with HLH/MAS.

RESULTS

The task force developed 6 overarching statements and 24 specific points to consider relevant to early recognition of HLH/MAS, diagnostic approaches, initial management and monitoring of HLH/MAS. Major themes included the simultaneous need for prompt syndrome recognition, systematic evaluation of underlying contributors, early intervention targeting both hyperinflammation and likely contributors, careful monitoring for progression/complications and expert multidisciplinary assistance.

CONCLUSION

These 2022 EULAR/American College of Rheumatology points to consider provide up-to-date guidance, based on the best available published data and expert opinion. They are meant to help guide the initial evaluation, management and monitoring of patients with HLH/MAS in order to halt disease progression and prevent life-threatening immunopathology.

[Treatment of hemophagocytic lymphohistiocytosis in patients in the intensive care unit]

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome characterized by hyperferritinemia. A differentiation is made between hereditary and acquired forms. In contrast to children, almost all cases in adult patients consist of acquired secondary HLH. Infections, malignancies and autoimmune diseases are frequent triggers of secondary HLH. More recently, cases of HLH have also been described in association with immunotherapy, e.g., when using chimeric antigen receptor (CAR) T‑cell treatment. In critically ill patients in the intensive care unit (ICU), sepsis represents the major differential diagnosis of HLH due to the frequently similar clinical presentation. Sometimes both sepsis and HLH are present at the same time. An early diagnosis and timely initiation of immunosuppressive treatment are essential for the further course and prognosis of HLH. Therefore, HLH should be considered as a possible diagnosis in critically ill patients with persistent fever and additional compatible symptoms (e.g., splenomegaly, neurological symptoms) or laboratory parameters (e.g., hyperferritinemia, cytopenia of two or three cell lines, increased transaminases). The diagnosis of HLH is made on the basis of the HLH-2004 criteria. The HScore can be used to estimate the probability of the presence of HLH. Corticosteroids given at high doses are the cornerstone of HLH treatment. Furthermore, immunoglobulins, etoposide, anakinra or ruxolitinib can complement treatment depending on the HLH trigger. The course of HLH depends on the timely initiation of treatment, the underlying trigger and the response to treatment. Despite progress in terms of diagnostics and targeted treatment, the prognosis of critically ill HLH patients is still poor.

The 2022 EULAR/ACR points to consider at the early stages of diagnosis and management of suspected haemophagocytic lymphohistiocytosis/macrophage activation syndrome (HLH/MAS)

OBJECTIVE

Haemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are life-threatening systemic hyperinflammatory syndromes that can develop in most inflammatory contexts. They can progress rapidly, and early identification and management are critical for preventing organ failure and mortality. This effort aimed to develop evidence-based and consensus-based points to consider to assist clinicians in optimising decision-making in the early stages of diagnosis, treatment and monitoring of HLH/MAS.

METHODS

A multinational, multidisciplinary task force of physician experts, including adult and paediatric rheumatologists, haematologist/oncologists, immunologists, infectious disease specialists, intensivists, allied healthcare professionals and patients/parents, formulated relevant research questions and conducted a systematic literature review (SLR). Delphi methodology, informed by SLR results and questionnaires of experts, was used to generate statements aimed at assisting early decision-making and optimising the initial care of patients with HLH/MAS.

RESULTS

The task force developed 6 overarching statements and 24 specific points to consider relevant to early recognition of HLH/MAS, diagnostic approaches, initial management and monitoring of HLH/MAS. Major themes included the simultaneous need for prompt syndrome recognition, systematic evaluation of underlying contributors, early intervention targeting both hyperinflammation and likely contributors, careful monitoring for progression/complications and expert multidisciplinary assistance.

CONCLUSION

These 2022 EULAR/American College of Rheumatology points to consider provide up-to-date guidance, based on the best available published data and expert opinion. They are meant to help guide the initial evaluation, management and monitoring of patients with HLH/MAS in order to halt disease progression and prevent life-threatening immunopathology.

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 > 60 years, Plt ≤ 20.0 × 109/L, APTT > 36.0 s 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 > 60 years and age ≤ 60 years 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 > 36.0 s and APTT ≤ 36.0 s 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 > 60 years, Plt ≤ 20.0 × 109/L, APTT > 36.0 s 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.

Secondary hemophagocytic lymphohistiocytosis: an unusual complication in disseminated Mycobacterium tuberculosis

Tuberculosis-associated hemophagocytic lymphohistiocytosis (TB-HLH) is a rare and life-threatening complication of tuberculosis infection. Early recognition and treatment of TB-HLH is crucial for improving outcomes. Treatment typically involves a combination of antituberculosis therapy and immunosuppressive therapy to control the immune system's overreaction. In this report, we present the case of a 53-year-old ambulance driver who was diagnosed with TB-HLH. His CT scan revealed splenic abscesses, hepatomegaly and bilateral lung consolidation. He subsequently developed multiorgan failure, including acute respiratory distress syndrome (ARDS), transaminitis and bone marrow dysfunction. The clinical course and simultaneous increase in serum ferritin raised the suspicion of HLH. His Hscore was 254, indicating a high probability of hemophagocytic syndrome. TB diagnosis was confirmed by positive endotracheal TB GeneXpert and bone marrow aspiration (BMA) which detected acid-fast bacilli organisms. The patient was promptly started on anti-TB, dexamethasone and IVIG. The patient responded well to treatment and made a full recovery without any lasting complications. This case highlights the importance of promptly recognising HLH and identifying the underlying cause. In critically ill patients, it is crucial not to delay HLH-specific treatment while working up for differential diagnosis.

Hemophagocytic Lymphohistiocytosis Caused by a Severe Epstein-Barr Virus Infection in a Young Patient Presenting With Hiccups

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome characterized by a pathologic immune response in the setting of infection, malignancy, acute illness, or any immunological stimulus. Infection is the most common etiology of HLH. HLH involves aberrant activation of lymphocytes and macrophages with resultant hypercytokinemia due to an inappropriately stimulated and ineffective immune response. Here, we present the case of a previously healthy 19-year-old male presenting with hiccups and scleral icterus, who was found to have HLH due to a severe Epstein-Barr virus infection. Despite a morphologically normal bone marrow biopsy, the patient met the diagnostic criteria for HLH, including a low natural killer cell count and elevated soluble interleukin-2 receptor. Notably, ferritin was severely elevated at 85,810 ng/mL. The patient was treated with an induction course of dexamethasone intravenously for eight weeks. Since HLH can progress into multi-organ failure, timely diagnosis and prompt initiation of treatment are critical. Novel disease-modifying therapies and further clinical trials are warranted to treat this potentially fatal immunological disease with multisystem ramifications.

sCD25 as an independent adverse prognostic factor in adult patients with HLH: results of a multicenter retrospective study

Hemophagocytic lymphohistiocytosis (HLH) is a rare but often fatal hyperinflammatory syndrome caused by an inborn or acquired error of immunity. In adults, the underlying immunodeficiency generally arises alongside severe infections, malignancies, autoimmune diseases, and immunosuppressive treatment. To analyze risk factors and outcome in adults, we conducted a multicenter retrospective study. A total of 62 adult (age ≥18 years) patients met at least one of the following inclusion criteria: (1) ≥5 of 8 HLH-2004 criteria, (2) HScore ≥ 200 plus 4 HLH-2004 criteria, or (3) mutation compatible with an HLH diagnosis. Most patients (65%) were male, and the median age at diagnosis was 53.5 years (range, 19-81 years). All patients were assigned to 4 etiologic subgroups based on their most likely HLH trigger. The survival probability of the 4 etiologic subgroups differed significantly (P = .004, log-rank test), with patients with an underlying malignancy having the worst clinical outcome (1-year survival probability of 21%). The parameters older age, malignant trigger, elevated serum levels of aspartate transferase, creatinine, international normalized ratio, lactate dehydrogenase, sCD25, and a low albumin level and platelet count at treatment initiation were significantly (P < .1) associated with worse overall survival in the univariate Cox regression model. In multivariate analysis, sCD25 remained the only significant prognostic factor (P = .005). Our results suggest that sCD25 could be a useful marker for the prognosis of patients with HLH that might help to stratify therapeutic interventions.

Ehrlichiosis-Associated Hemophagocytic Lymphohistiocytosis: A Case Series and Review of the Literature

Background

Human monocytic ehrlichiosis (HME) is a potentially life-threatening tick-borne illness. HME-associated hemophagocytic lymphohistiocytosis (HLH) is a rare entity with a paucity of published literature regarding treatment and outcome. We present the clinical features, treatment, and outcomes of 4 patients at our institutions with HME-associated HLH. This review also summarizes the current literature regarding the presentation, treatment, and outcome of this infection-related HLH.

Methods

We searched the PubMed database for case reports and case series. All cases were diagnosed according to the HLH-04 criteria.

Results

Four cases of HME-associated HLH were included from our institutions. The literature review yielded 30 additional cases. About 41% of the cases were in the pediatric population; 59% were female; and all patients had fever, cytopenia, and elevated ferritin. Most patients were immunocompetent; all but one patient with available data were treated with doxycycline, and eight of the patients with available data received the HLH-94 treatment protocol. The mortality rate was 17.6%.

Conclusions

HME-associated HLH is a rare but serious syndrome with significant mortality. Early treatment with doxycycline is critical, but the role of immunosuppressive therapy is individualized.

Hemophagocytic Lymphohistiocytosis Secondary to Chronic Lymphocytic Leukemia Progression

Hemophagocytic lymphohistiocytosis (HLH) is an acute, rare systemic hyperinflammatory disorder caused by a dysregulated immune cell function and massive cytokine release, often leading to multiple organ involvement and failure. Fever, hepatosplenomegaly, cytopenia, elevated liver enzymes, hypertriglyceridemia, and hyperferritinemia are the hallmarks of the disease. Its primary (genetic) form is typically observed in pediatric patients and its secondary, acquired form is seen in adult patients with an underlying autoimmune, malignant, or infectious disease. It is not frequently reported in patients with chronic lymphocytic leukemia (CLL) without an infectious or pharmacological trigger. We present a case of a 71-year-old patient with hemophagocytic lymphohistiocytosis due to the progression of chronic lymphocytic leukemia.

Case report: Ruxolitinib plus dexamethasone as first-line therapy in haemophagocytic lymphohistiocytosis

Haemophagocytic lymphohistiocytosis (HLH) is a cytokine-driven inflammatory syndrome caused by uncontrolled hypersecretion of inflammatory cytokines. Conventional first-line treatment for HLH included HLH-94 and HLH-2004 regimens. However, quite a few patients do not respond to treatment or cannot tolerate intensive chemotherapy. We reported two cases of HLH, one caused by natural killer (NK)/T-cell lymphoma and another associated with missense variants in the perforin 1 gene. They both received the ruxolitinib plus dexamethasone protocol and had a rapid response to treatment without obvious adverse effects. Our report indicates that treatment with ruxolitinib plus dexamethasone might be a potential option for HLH, and clinical trials warrant further investigation. In addition, the detection of HLH-related genes is necessary for the identification of late-onset familial HLH in certain settings.

A predictive model for identifying secondary underlying diseases of hemophagocytic lymphohistiocytosis

Background

Secondary hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening disease of immune hyperactivation that arises in the context of infectious, inflammatory, or neoplastic triggers. The aim of this study was to establish a predictive model for the timely differential diagnosis of the original disease resulting in HLH by validating clinical and laboratory findings to further improve the efficacy of therapeutics for HLH.

Methods

We retrospectively enrolled 175 secondary HLH patients in this study, including 92 patients with hematologic disease and 83 patients with rheumatic disease. The medical records of all identified patients were retrospectively reviewed and used to generate the predictive model. We also developed an early risk score using multivariate analysis weighted points proportional to the β regression coefficient values and calculated its sensitivity and specificity for the diagnosis of the original disease resulting in HLH.

Results

The multivariate logistic analysis revealed that lower levels of hemoglobin and platelets (PLT), lower levels of ferritin, splenomegaly and Epstein-Barr virus (EBV) positivity were associated with hematologic disease, but young age and female sex were associated with rheumatic disease. The risk factors for HLH secondary to rheumatic diseases were female sex [OR 4.434 (95% CI, 1.889-10.407), P =0.001], younger age [OR 6.773 (95% CI, 2.706-16.952), P<0.001], higher PLT level [OR 6.674 (95% CI, 2.838-15.694), P<0.001], higher ferritin level [OR 5.269 (95% CI, 1.995-13.920), P =0.001], and EBV negativity [OR 27.656 (95% CI, 4.499-169.996), P<0.001]. The risk score included assessments of female sex, age, PLT count, ferritin level and EBV negativity, which can be used to predict HLH secondary to rheumatic diseases with an AUC of 0.844 (95% CI, 0.836~0.932).

Conclusion

The established predictive model was designed to help clinicians diagnose the original disease resulting in secondary HLH during routine practice, which might be improve prognosis by enabling the timely treatment of the underlying disease.

Epidemiology of haemophagocytic lymphohistiocytosis at the population level in Germany

We retrospectively analysed all German inpatient cases of haemophagocytic lymphohistiocytosis (HLH) from 2014 to 2020 to describe the epidemiology, clinical course, and underlying diseases of 4065 HLH patients. The age-standardized incidence rate of HLH in Germany was 0.52/100 000 people in 2014 and steadily increased by 10% per year to 0.97/100 000 in 2020 (mean 0.70/100 000). Inpatient deaths related to HLH increased from 0.84/1 000 000 people in 2014 to 2.32/1 000 000 people in 2020, caused by rising numbers of older HLH patients. Overall, HLH is more frequent than previously expected and incidence as well as HLH-related deaths increased significantly.

"A Dangerous Black Box:" Idiopathic Hemophagocytic Lymphohistiocytosis in Adult Patients-A Case Report and Review of the Literature

Hemophagocytic lymphohistiocytosis (HLH) is a rare potentially life-threatening condition characterized by aberrant inflammation that can be related to genetic or sporadic forms. In both forms, triggering factors may be involved. Early detection of the underlying cause is crucial for therapeutic decision, while early intervention might be associated with better outcomes. The largest descriptions in the literature on HLH refer to pediatric cases. Adolescents and adults may also be affected, but there is scarce evidence regarding their diagnosis and management. We describe here the case of a 68-year-old Swiss woman with HLH, in whom an extensive search for underlying causes was performed, but neither trigger nor pathogenic variant was found. An early intervention first with dexamethasone and later with cyclosporine was performed. The patient showed a favorable response and did not require further hospitalization; however, one year after diagnosis, it was not possible to suspend cyclosporine due to recurrence of laboratory inflammation signs by drug tapering. The occurrence of HLH idiopathic forms represents a challenge; failure to identify the underlying triggering cause generates uncertainty, endless diagnostic investigations, and consequently additional delays in the treatment. This manuscript addresses the difficulties on this issue.

Temporal Trends in the Incidence of Hemophagocytic Lymphohistiocytosis: A Nationwide Cohort Study From England 2003-2018

Hemophagocytic lymphohistiocytosis (HLH) is rare, results in high mortality, and is increasingly being diagnosed. We aimed to quantify the incidence of diagnosed HLH and examine temporal trends in relation to age and associated diseases. Using national linked electronic health data from hospital admissions and death certification cases of HLH that were diagnosed in England between January 1, 2003, and December 31, 2018. We calculated incidence rates of diagnosed HLH per million population by calendar year, age group, sex, and associated comorbidity (hematological malignancy, inflammatory rheumatological or bowel diseases [IBD]). We modeled trends in incidence and the interactions between calendar year, age, and associated comorbidity using Poisson regression. There were 1674 people with HLH diagnosed in England between 2003 and 2018. The incidence rate quadrupled (incidence rate ratio [IRR] 2018 compared to 2003: 3.88, 95% confidence interval [CI] 2.91 to 5.28), increasing 11% annually (adjusted IRR 1.11, 95% CI 1.09 to 1.12). There was a transition across age groups with greater increases in those aged 5-14 years of HLH associated with rheumatological disease/IBD compared with hematological malignancy, with similar increases in HLH associated with both comorbidities for those 15-54, and greater increases in HLH associated with hematological malignancies for those 55 years and older. The incidence of HLH in England has quadrupled between 2003 and 2018. Substantial variation in the incidence occurred with inflammatory rheumatological diseases/IBD-associated HLH increasing more among the younger age groups, whereas in older age groups, the largest increase was seen with hematological malignancy-associated HLH.

Hemophagocytic Lymphohistiocytosis in Adults: A Retrospective Study in a Belgian Teaching Hospital

Introduction

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease, which can be primary (due to genetic mutation) or secondary to malignancy, infection and rheumatologic diseases. Data concerning Belgian patients with adult HLH are lacking.

Methods

This retrospective study was performed in a teaching hospital in Belgium. All cases of adult HLH, from December 2010 to April 2022, were reviewed. Patients with more than five HLH-2004 criteria and/or HScore >80% were included in the study. The objective of our study was to describe clinical and biological characteristics of patients with HLH and attempt to look for variables associated with mortality.

Results

Fifty-two patients were included in the final analysis. Mean age (SD) of patients was 48 (18) years old, and 29 patients were of male gender (56%). The underlying diseases associated with HLH were malignancy (M-HLH) in 22 patients, infection related HLH in 20 patients, rheumatologic disease related HLH in 7 patients, idiopathic in 2 patients and secondary to pregnancy in 1 patient. Overall mortality, mortality at 30 days and 90 days were 24/52 (46%), 13/52 (25%) and 4/52 (10%), respectively. In univariate analysis, malignancy, male sex, age and disseminated intravascular coagulation (DIC) were associated with mortality (p < 0.05). In multivariate analysis, only age was significantly associated with mortality (odds ratio, 1.053; 95% confidence interval, 1.016–1.092; p 0.005).

Conclusion

In our study, the most frequent triggers were malignancy and infectious agent followed by rheumatologic disease. Risk factors for mortality were age, male sex, malignancy and DIC, but only age remained significant in multivariate analysis. Treatment guidelines are mainly based on pediatric patients, and it is important for physician to describe adult patients’ outcome to better understand this disease and adapt treatment.

Diagnosing Hemophagocytic Lymphohistiocytosis with Machine Learning: A Proof of Concept

Hemophagocytic lymphohistiocytosis is a hyperinflammatory syndrome characterized by uncontrolled activation of immune cells and mediators. Two diagnostic tools are widely used in clinical practice: the HLH-2004 criteria and the Hscore. Despite their good diagnostic performance, these scores were constructed after a selection of variables based on expert consensus. We propose here a machine learning approach to build a classification model for HLH in a cohort of patients selected by glycosylated ferritin dosage in our tertiary center in Lyon, France. On a dataset of 207 adult patients with 26 variables, our model showed good overall diagnostic performances with a sensitivity of 71.4% and high specificity, and positive and negative predictive values which were 100%, 100%, and 96.9%, respectively. Although generalization is difficult on a selected population, this is the first study to date to provide a machine-learning model for HLH detection. Further studies will be required to improve the machine learning model performances with a large number of HLH cases and with appropriate controls.

Hemophagocytic lymphohistiocytosis in HIV-associated lymphoproliferative disorders

Compared to the general population the incidence of lymphoproliferative disorders (LPDs) is significantly elevated among people living with HIV (PLHIV). In high-income countries LPDs have become the most common HIV-associated cause of death among PLHIV. Lymphomas are one of the most frequent triggers of Hemophagocytic Lymphohistiocytosis (HLH), a life-threatening inflammatory syndrome that manifests as a sepsis-like syndrome thus obscuring the underlying condition and delaying its diagnosis and therapy. We performed this retrospective cohort study comprising all adult HIV-infected patients who started treatment for histologically proven LPDs between October 2013 and July 2019, to analyse risk factors, frequency and outcome of HLH among HIV-infected patients with LPDs. Of 75 patients, six (8%) presented with or developed HLH. Three patients had Hodgkin lymphoma and three had HHV-8 associated diseases. There was a significant correlation (p<0.01) between bone marrow involvement and the development of HLH. HLH was associated with lower overall survival (HR: 5.09; 95%CI: 1.53 - 16.91 p=0.008). In conclusion HLH appears to be more frequent in HIV-associated lymphomas than in HIV-negative lymphomas. The probability of developing HLH was particularly high in patients with Hodgkin lymphoma, lymphoma with bone marrow infiltration and HHV-8 associated lymphoma. Mortality was significantly increased in the presence of HLH.

Serum soluble interleukin-2 receptor (sIL-2R) is an accurate biomarker for dengue-associated hemophagocytic lymphohistiocytosis syndrome diagnosed by Hscore

Objective

Hemophagocytic lymphohistiocytosis is a potentially fatal complication of severe dengue fever. Here we evaluated the serum soluble IL-2R levels as potential biomarker for identifying HLH in patients with dengue fever.

Methods

In this cross-sectional study conducted in a tertiary care center of a teaching hospital, subjects with dengue and fever of more than 5 days, leukopenia/thrombocytopenia and/or hepatosplenomegaly were studied. Data were collected to compare sIL-2R values and serum ferritin with Hscore and Histiocyte Society 2004 criteria. Relevant statistical methods were used.

Results

80 subjects with severe dengue fever were analyzed with relevant investigations. Mean H score was 219.2 ± 17.6 in 18 dengue patients with HLH v/s 166.2 ± 11.2 in 62 patients without HLH (p =  < 0.001). Serum ferritin (11,230.5 v/s 7853.5, p = 0.013) and sIL-2R (32,917.5 v/s 6210, p = < 0.001) were significantly higher in those patients with HLH. sIL-2R correlated very well with HScore (r = 0.98, p < 0.001) compared to ferritin (r = 0.51, p < 0.001) with an AUROC of 1.00 compared to 0.694 (95% CI 0.557–0.831) of serum ferritin for diagnosing HLH. A cut-off value of 10,345 pg/ml for sIL-2R had a sensitivity and specificity of 100% for HLH, whereas, a ferritin value of 8613 ng/ml had only 67% sensitivity and 55% specificity.

Conclusion

sIL-2R could be a single most useful biomarker to differentiate dengue fever patients who are likely to progress to HLH, from those that are not. Full workup for HLH could be limited only to those patients with elevated sIL-2R, especially in resource limited settings.

Supplementary Information

The online version contains supplementary material available at 10.1007/s15010-022-01906-8.

Pediatric hemophagocytic lymphohistiocytosis in a tropical country: Results of a multicenter study in Thailand

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening condition caused by genetic mutation or various triggers disturbing the immune system.

METHODS

A multicenter retrospective study of pediatric patients with HLH receiving a diagnosis between January 2005 and December 2019 from three pediatric oncology centers was conducted to explore the clinical characteristics and determine prognostic factors associated with outcomes among Thai children.

RESULTS

In all, 78 patients with HLH with a median age at diagnosis of 3.17 (range, .08-17.83) years were enrolled. The male to female ratio was 1.2:1. The most common type of HLH was infection-associated hemophagocytic syndrome (IAHS) (n = 59, 75%) of which Epstein-Barr virus was the most common pathogen. Thrombocytopenia, hyperbilirubinemia, and treatment response at weeks 2 and 8 after initiating treatment were associated with mortality. Platelet count <50,000 cells/mm³ was the only independent prognostic factor to define survival outcome (p-value .035). Two-year overall survival rate was 71.3% (95% confidence interval, 59.2%-80.3%). Survival rates between IAHS, malignant associated HLH, macrophage activation syndrome, and unspecific HLH did not significantly differ (p-value .571).

CONCLUSION

IAHS was the most common cause among pediatric HLH in Thailand. The outcomes of Thai children with HLH were comparable to those of developed countries. Platelet count <50,000 cells/mm³ was the only independent prognostic factor to define survival outcome.

Macrophage activation syndrome in rheumatic disease: Clinical characteristics and prognosis of 20 adult patients

Objectives

Macrophage activation syndrome (MAS) is a hyperinflammatory condition that is known to be secondary hemophagocytic lymphohistiocytosis (HLH) in patients with rheumatic disease. The aim of study was to evaluate the clinical manifestations and outcomes in patients with MAS with rheumatic disease.

Materials and methods

We performed a retrospective study of 20 adult patients who were diagnosed with MAS from 2012 to 2020. MAS was classified according to the HLH-2004 criteria. Patients’ information, including clinical features, laboratory findings, and treatment regimens, was collected, and the overall survival rate was estimated by the Kaplan–Meier method.

Results

Twenty patients (18 women, 35.6 ± 18.3 years) who met the HLH-2004 criteria also fulfilled the 2016 EULAR/ACR/PRINTO classification criteria for MAS, and HScore was higher than 169 (mean, 241.1). Fourteen patients with systemic lupus erythematosus and 6 patients with adult-onset Still’s disease were included. All patients were treated initially with corticosteroids, and 16 patients required additional immunosuppressants. The overall survival at 3 and 6 months was 75.2% and 64.3%. In survivors, renal impairment was less common (7.7% versus 71.4%, p = 0.007), the levels of AST (364.0 versus 81.0 IU/L, p = 0.019) and LDH (1346.0 versus 343.0IU/L, p = 0.014), and platelet count (90.0 versus 43.0 × 109/L, p = 0.02) were higher in compared to non-survivors. Nine patients had opportunistic infections, five of whom died during admission.

Conclusion

The mortality of patients with MAS associated with rheumatic disease remains high. Renal impairment, levels of AST and LDH, and platelet count might be associated with prognosis.

Incidence and survival of haemophagocytic lymphohistiocytosis: A population-based cohort study from England

BACKGROUND

Haemophagocytic lymphohistiocytosis (HLH) is a rare hyper-inflammatory condition with poor outcomes.

OBJECTIVES

Few population-based estimates of the incidence and survival in adults exist. We aimed to provide these data for England.

METHODS

We used population-based linked data from primary care, secondary care, cancer registries and mortality databases in England to identify people diagnosed with HLH between 1 January 2000 and 31 December 2016. We calculated annual incidence rates by age and sex, modelled change in incidence over time with Poisson regression, calculated overall 1-year survival using Kaplan-Meier methods and estimated adjusted hazard ratios (HRs) of death using a Cox proportional hazards model.

RESULTS

We identified 214 patients with HLH. The reported age and sex-adjusted incidence increased twofold over the period, from around one to around two per million. Incidence was highest in those below 1 year (14.6 per million) and ≥75 years (2.2 per million), and lowest in those aged 15-44 years (0.8 per million). One-year survival varied by age and sex from 77% (95% confidence interval [CI] 63%-86%) in those <15 years to 30% (95% CI 14%-49%) in those ≥75. In patients with haematological cancer, the adjusted HR for death was 2.60 (95% CI 1.45-4.66) compared to patients with no malignant or rheumatological disease.

CONCLUSION

The incidence of HLH diagnosis in England has increased between 2000 and 2016 and occurs in all ages with varying underlying diseases. One-year survival varies substantially, being particularly poor in those aged over 75 years and those with haematological malignancy.