Hemophagocytic lymphohistiocytosis complicating septicemic melioidosis: A case report

Melioidosis is an infectious disease caused by Burkholderia pseudomallei. People infected with B. pseudomallei experience fever and skin changes, pneumonia, abscesses, and septic shock that could cause death. Hemophagocytic lymphohistiocytosis is a severe inflammatory syndrome due to the excess activation of macrophages and T cells. We report a 50-year-old hypertensive and diabetic male patient presented with high-grade intermittent fever with loss of appetite and weight loss for two months and a history of jaundice, backache and swelling of both feet for 15 days. Blood and bone marrow culture grew Burkholderia pseudomallei. A liver biopsy revealed Kupffer cell hyperplasia and hemophagocytosis. The patient was treated with an injection of dexamethasone 4mg intravenous three times a day for five days and tapered over 15 days with ceftazidime 2 gm intravenous three times a day for six weeks. Early suspicion in the diagnosis of hemophagocytic lymphohistiocytosis in septicemia can prevent severe complications, even death.

Development and validation of an early mortality risk model for pediatric hemophagocytic lymphohistiocytosis: a comparison with HScore, PELOD-2, P-MODS, and pSOFA

There has been no severity evaluation model for pediatric patients with hemophagocytic lymphohistiocytosis (HLH) that uses readily available parameters. This study aimed to develop a novel model for predicting the early mortality risk in pediatric patients with HLH using easily obtained parameters whatever etiologic subtype. Patients from one center were divided into training and validation sets for model derivation. The developed model was validated using an independent validation cohort from the second center. The prediction model with nomogram was developed based on logistic regression. The model performance underwent internal and external evaluation and validation using the area under the receiver operating characteristic curve (AUC), calibration curve with 1000 bootstrap resampling, and decision curve analysis (DCA). Model performance was compared with the most prevalent severity evaluation scores, including the PELOD-2, P-MODS, and pSOFA scores. The prediction model included nine variables: glutamic-pyruvic transaminase, albumin, globulin, myohemoglobin, creatine kinase, serum potassium, procalcitonin, serum ferritin, and interval between onset and diagnosis. The AUC of the model for predicting the 28-day mortality was 0.933 and 0.932 in the training and validation sets, respectively. The AUC values of the HScore, PELOD-2, P-MODS and pSOFA were 0.815, 0.745, 0.659 and 0.788, respectively. The DCA of the 28-day mortality prediction exhibited a greater net benefit than the HScore, PELOD-2, P-MODS and pSOFA. Subgroup analyses demonstrated good model performance across HLH subtypes. The novel mortality prediction model in this study can contribute to the rapid assessment of early mortality risk after diagnosis with readily available parameters.

Beta 2-microglobulin is an independent risk marker of acute kidney injury in adult patients with hemophagocytic lymphohistiocytosis

BACKGROUND AND AIMS

The role of beta2-microglobulin (β2-MG) in predicting acute kidney injury (AKI) in hemophagocytic lymphohistiocytosis patients has been poorly studied. This study aimed to analyze the clinical characteristics of hemophagocytic lymphohistiocytosis patients and identify risk factors that predict AKI development.

METHODS

This retrospective observational cohort study conducted at a single-center involved 938 patients diagnosed with hemophagocytic lymphohistiocytosis, who were divided into AKI  group and non-AKI group. Patient data were collected and analyzed using univariate and multivariate binary logistic regression to identify potiential risk factors associated with AKI occurrence.   RESULTS: Among the enrolled patients, 486 were male (51.9%), the median age was 37 years (interquartile range, 28.0, 52.0), 58.4% experienced AKI. Mechanical ventilation (8.0% vs. 0.8%) and vasopressor support (21.7% vs. 4.1%) occurred at significantly higher rates in the AKI group compared to the non-AKI group, with significantly higher in-hospital mortality (5.5% vs. 1.3%) and 28-day mortality (12.8% vs. 5.4%). When β2-MG was used as a continuous variable, multifactorial analysis showed that β2-MG, transplantation, and vasopressor support were independently associated with risk for the development of AKI.

CONCLUSIONS

The incidence of morbidity and mortality in patients with hemophagocytic lymphohistiocytosis complicated by AKI remains high. Monitoring levels of β2-MG may provide clinicians with timely indicators of changes in renal function,  facilitating adjustments to treatment strategies.

Secondary hemophagocytic lymphohistiocytosis in pediatric patients with visceral leishmaniasis and Epstein-Barr virus infection

Visceral leishmaniasis-associated hemophagocytic lymphohistiocytosis (VL-HLH) is indistinguishable from those of HLH of other etiologies due to the overlap symptoms, posing a serious threat to life. In this study, we aimed to provide insights for early diagnosis and improve outcomes in pediatric patients with VL-HLH. We retrospectively analyzed the clinical and laboratory data of 10 pediatric patients with VL-HLH and 58 pediatric patients with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH). The median time from symptom onset to cytopenia in patients with VL-HLH and EBV-HLH was 11 days (interquartile range, 7-15 days) and five days (interquartile range, 3.75-9.25 days) (P = 0.005). Both groups showed liver injury and increased lactate dehydrogenase levels; however the levels of aspartate aminotransferase, alanine aminotransferase, direct bilirubin, and lactate dehydrogenase in patients with VL-HLH were significantly lower than those in patients with EBV-HLH (P < 0.05). The fibrinogen and triglyceride levels were almost normal in VL-HLH patients but were significantly altered in EBV-HLH cases ( P < 0.05). The positive rate of first bone marrow microscopy examination, anti-rK39 IgG detection, and blood metagenomic next-generation sequencing was 50%, 100%, and 100%, respectively. After VL diagnosis, eight patients were treated with sodium stibogluconate and two were treated with liposomal amphotericin B. All the patients with VL-HLH recovered. Our study demonstrates that regular triglyceride and fibrinogen levels in pediatric patients with VL-HLH may help in differential diagnosis from EBV-HLH. VL-HLH is milder than EBV-HLH, with less severe liver injury and inflammatory responses, and timely treatment with antileishmanial agents is essential to improve the outcomes of pediatric patients with VL-HLH.

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.

Single-Cell Transcriptomic Analysis of Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis

Epstein-Barr virus (EBV) infection can lead to infectious mononucleosis (EBV-IM) and, more rarely, EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH), which is characterized by a life-threatening hyperinflammatory cytokine storm with immune dysregulation. Interferon-gamma (IFNγ) has been identified as a critical mediator for primary HLH; however, the detailed role of IFNγ and other cytokines in EBV-HLH is not fully understood. In this study, we used single-cell RNA sequencing to characterize the immune landscape of EBV-HLH and compared it with EBV-IM. Three pediatric patients with EBV-HLH with different backgrounds, one with X-linked lymphoproliferative syndrome type 1 (XLP1), two with chronic active EBV disease (CAEBV), and two patients with EBV-IM were enrolled. The TUBA1B + STMN1 + CD8 + T cell cluster, a responsive proliferating cluster with rich mRNA detection, was explicitly observed in EBV-IM, and the upregulation of SH2D1A-the gene responsible for XLP1-was localized in this cluster. This proliferative cluster was scarcely observed in EBV-HLH cases. In EBV-HLH cases with CAEBV, upregulation of LAG3 was observed in EBV-infected cells, which may be associated with an impaired response by CD8 + T cells. Additionally, genes involved in type I interferon (IFN) signaling were commonly upregulated in each cell fraction of EBV-HLH, and activation of type II IFN signaling was observed in CD4 + T cells, natural killer cells, and monocytes but not in CD8 + T cells in EBV-HLH. In conclusion, impaired responsive proliferation of CD8 + T cells and upregulation of type I IFN signaling were commonly observed in EBV-HLH cases, regardless of the patients' background, indicating the key features of EBV-HLH.

Hemophagocytic lymphohistiocytosis and macrophage activation syndrome: two rare sides of the same devastating coin

Hemophagocytic lymphohistiocytosis (HLH) is a rare genetic hyperinflammatory syndrome that occurs early in life. Macrophage activation syndrome (MAS) usually refers to a secondary form of HLH associated with autoimmunity, although there are other causes of secondary HLH, such as infections and malignancy. In this article, we reviewed the concepts, epidemiology, clinical and laboratory features, diagnosis, differential diagnosis, prognosis, and treatment of HLH and MAS. We also reviewed the presence of MAS in the most common autoimmune diseases that affect children. Both are severe diseases that require prompt diagnosis and treatment to avoid morbidity and mortality.

Severe flea-borne typhus complicated by hemophagocytic lymphohistiocytosis: A case report and review of literature

Flea-borne typhus (FBT), also known as murine typhus, is a zoonotic infection caused by R. typhi with world-wide distribution. In the United States, the infection is uncommon but remains endemic in some areas, including Los Angeles County. It typically manifests as a benign acute febrile illness but can be complicated in a minority of cases. Associated hemophagocytic lymphohistiocytosis (HLH) has been described in a limited number of cases. Here, we present a case of a patient with FBT complicated by HLH treated empirically with doxycycline with subsequent resolution of HLH. Also included is a review of the literature of other published cases.

Ruxolitinib-loaded cytokine nanosponge alleviated the cytokine storm and dampened macrophage overactivation for the treatment of hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening clinical syndrome characterized by a positive feedback loop between cytokine storm and macrophages and lymphocytes overactivation, which could serve as a valid therapeutic target for HLH treatment. In this study, the clinically extensively used JAK1/2 inhibitor ruxolitinib was encapsulated into macrophage membrane-coated nanoparticles (M@NP-R) with high drug-loading efficiency for targeted HLH treatment. In vitro and in vivo studies demonstrated that M@NP-R not only efficiently adsorbed extracellular proinflammation cytokines, like IFN-γ and IL-6 to alleviate the cytokine storm, but also effectively dampened macrophage activation and proliferation by intracellular JAK/STAT signaling pathway inhibition. M@NP-R treatment significantly ameliorated the clinical and laboratory manifestations of HLH in mouse models, including trilineage cytopenia, hypercytokinemia, organomegaly, hepatorenal dysfunction, and tissue inflammation. Importantly, M@NP-R significantly enhanced the survival of the lethal HLH mice. Altogether, M@NP-R successfully blocked the positive feedback loop between the cytokine storm and macrophage overactivation by depleting extracellular inflammatory cytokines and inhibiting the intracellular JAK/STAT signaling pathway, both of which worked synergistically in HLH treatment. As ruxolitinib has already been extensively used in clinics with favorable safety, and M@NP is biodegradable and highly biocompatible, M@NP-R has good prospects for clinical translation.

Hemophagocytic lymphohistiocytosis and myopericarditis induced by campylobacter: a case report

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a severe disorder characterized by excessive activation of the immune system, leading to hypercytokinemia and damage to multiple organs. We report a rare case of HLH with myopericarditis caused by Campylobacter infection.

CASE PRESENTATION

A 28-year-old male patient with a history of hypertension without medicine control presented at the hospital after a four-day fever, decreasing urine amount, rashes on his trunk and limbs, and other symptoms. He was admitted with a provisional diagnosis of atypical infection and allergic skin rash related to diclofenac. However, his condition deteriorated, and he developed shock, tachycardia, chest distress, and bilateral pleural effusion after admission. Further investigations revealed cardiogenic shock related to myopericarditis, and he was transferred to the ICU. In addition, a stool PCR panel subsequently revealed a positive result for Campylobacter. On day 6, he was diagnosed with HLH. Under Clarithromycin and dexamethasone infusion, leukocytosis, anemia and thrombocytopenia with cardiogenic shock status improved. Then, he was later discharged in stable condition.

CONCLUSIONS

HLH and myopericarditis caused by Campylobacter are very rare. Early detection of Campylobacter-induced HLH and multiple organ failure, as well as prompt use of antibiotics and immunosuppressants, can be helpful for prognosis.

Clinical significance and different strategies for re-elevation of plasma EBV-DNA during treatment in pediatric EBV-associated hemophagocytic lymphohistiocytosis

OBJECTIVE

Monitoring the disease status of Epstein-Barr virus (EBV)-related hemophagocytic lymphohistiocytosis (HLH) patients is crucial. This study aimed to investigate the different strategies and outcomes of patients with EBV-HLH and re-elevated EBV-DNA.

METHOD

A retrospective analysis was conducted on 20 patients diagnosed with EBV-HLH. Clinical features, laboratory tests, treatments, plasma EBV-DNA levels, and outcomes were assessed. Three cases were highlighted for detailed analysis.

RESULTS

Nine of the 20 patients had a re-elevation of EBV-DNA during treatment, and 55.5 % (5/9) experienced relapses. Patients with persistently positive plasma EBV-DNA (n = 4) and those with re-elevated EBV-DNA after conversion (n = 9) showed a significantly higher relapse rate compared to those with persistently negative EBV-HLH (n = 7) (p < 0.05). Among the highlighted cases, Case 1 exhibited plasma EBV-DNA re-elevation after four weeks of treatment without relapse, maintaining stability with the original treatment regimen, and eventually, his plasma EBV-DNA turned negative. In Case 2, plasma EBV-DNA was elevated again with a recurrence of HLH after L-DEP. Consequently, she underwent allogeneic hematopoietic stem cell transplantation and eventually achieved complete remission (CR) with negative plasma EBV-DNA. Case 3 experienced plasma EBV-DNA re-elevation after L-DEP but remained in CR, discontinuing chemotherapy without relapse.

CONCLUSION

The re-elevation of plasma EBV-DNA during EBV-HLH treatment poses challenges in determining disease status and treatment strategies. Optimal management decisions require a combination of the level of elevated EBV-DNA, the intensity of hyperinflammation, and the patient's immune function.

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 in Egyptian children: diagnosis, treatment challenges, and outcome

BACKGROUND

Hemophagocyticlymphohistiocytosis (HLH) is a spectrum of immune activation which could be genetically determined, or secondary to an underlying illness. Our aim was to present the clinico-genetic aspects of HLH among Egyptian children and to evaluate the patterns of reactivation and outcome with illustrations of overlap manifestations.

RESEARCH DESIGNAND METHODS

We retrospectively collected the data of 55 patients with HLH, registered at Ain Shams University Children's Hospital,Cairo, Egypt.

RESULTS

Median age at diagnosis was 19 months (range 2-180), 33 patients (60%) fulfilled the diagnostic HLH criteria at presentation. Fourteen (25.45%) patients had secondary HLH, 15 (27.27%) patients had genetically documented familial HLH (11 had variants in UNC13D gene and one in PRF1 gene), 3 had Griscelli and Chediak-Higashi syndromes. Sixteen patients (29.1%) had reactivations, 8 (50%) of them had molecularly confirmed HLH. We report the death of 40 patients, the median duration from the diagnosis to death of 5 months mostly due to disease activity.

CONCLUSIONS

This study confirms that the nonspecific signs and symptoms of HLH are challenging. Genetic testing, though expensive and sophisticated, is integral for the diagnosis. The difficulty in finding non-related donors for stem cell transplantation and the early reactivations are the causes of the inferior outcome.

A Nationwide Retrospective Analysis of Allogeneic Hematopoietic Stem Cell Transplantation for Adult Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening disorder characterized by systemic hyperinflammation. Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the only potentially curative treatment for primary and relapsed/refractory HLH, the optimal strategy has not been established. We retrospectively analyzed 56 adult patients (≥18 years) with primary and secondary HLH (mainly consisting of Epstein-Barr virus-associated HLH) who underwent allo-HSCT using the registry database of the Japanese Society for Transplantation and Cellular Therapy, including 26 patients who underwent cord blood transplantation (CBT). One-fourth of patients received myeloablative conditioning (MAC), mainly consisting of total body irradiation-based regimens. The 3-year overall survival (OS) was 40.6%, while the 3-year cumulative incidences of relapse and non-relapse mortality (NRM) were 19.8% and 39.6%, respectively. In univariable analysis, age at allo-HSCT (the 3-year OS: 27.5% for ≥ 25 years old vs 58.0% for < 25 years old, P = .025), conditioning intensity (7.1% for MAC vs 51.8% for reduced-intensity conditioning (RIC), P = .002), and donor source (26.0% for CBT vs 52.9% for bone marrow or peripheral blood stem cell transplantation (BMT/PBSCT), P = .030) were associated with significantly inferior OS. In multivariable analysis, older age at allo-HSCT (≥ 25 years old) (Hazard ratio [HR], 2.37; 95% CI, 1.01 to 5.58; P = .048), MAC (HR, 2.45; 95% CI, 1.09 to 5.53; P = .031), and CBT (HR, 2.21; 95% CI, 1.04 to 4.71; P = .040) were independently associated with worse OS. In addition, only conditioning intensity predicted higher NRM (the 3-year NRM: 78.6% for MAC vs 26.6% for RIC), while no factors were associated with the relapse rate. This study includes the largest number of adult HLH patients undergoing CBT. Although the use of CBT is acceptable, BMT/PBSCT are more favorable strategies in allo-HSCT in adult HLH. Regarding conditioning intensity, RIC regimens are more beneficial in this setting.

Successful treatment of hemophagocytic lymphohistiocytosis in a patient with systemic lupus erythematosus with ruxolitinib: a case report

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening hematological disorder characterized by uncontrolled activation of CD8+ T and natural killer cells, leading to a cytokine storm and severe organ dysfunction. Although secondary HLH related to autoimmune diseases usually demonstrates a good treatment response to immunosuppressive therapy for underlying conditions, there is no consensus regarding the treatment in case of unresponsiveness to the treatment. Herein, we present a case of HLH that was unresponsive to high-dose glucocorticoid and cyclosporine treatment in a patient with newly diagnosed systemic lupus erythematosus. The patient's clinical features and laboratory abnormalities rapidly improved with ruxolitinib, an oral Janus kinase 1 and 2 (JAK1/2) inhibitor. This result suggests that blocking JAK-STAT pathway may be a potential treatment option in patients with refractory HLH secondary to autoimmune diseases.

Hemophagocytic lymphohistiocytosis after solid organ transplantation: A challenge for clinicians

Hemophagocytic lymphohistiocytosis (HLH) is a rare inflammatory disorder with a high mortality rate and a wide range of symptoms. Solid organ transplantation, which provides patients with a unique immunosuppressive state, is a less common predisposing factor for HLH. HLH after solid organ transplantation (HLH-SOT) is very rare and fatal. It is hard to diagnose and treat and extremely understudied. The use of immunosuppressants makes the situation of HLH-SOT more complex. This review summarizes the existing literature on HLH after solid organ transplantation and describes its triggers and symptoms, focusing on its diagnosis and treatment. We performed a literature search of case reports, case series, letters to the editor, and clinical quizzes describing patients with HLH after solid organ transplantation (HLH-SOT). We provide recommendations on the diagnosis protocol and treatment strategy based on the existing evidence.

Low interleukin-10 level indicates a good prognosis in Salmonella enterica serovar typhimurium-induced pediatric hemophagocytic lymphohistiocytosis: A case report

BACKGROUND

Secondary hemophagocytic lymphohistiocytosis (sHLH) triggered by Salmonella enterica serovar Typhimurium is rare in pediatric patients. There is no consensus on how to treat S. typhimurium-triggered sHLH.

CASE SUMMARY

A 9-year-old boy with intermittent fever for 3 d presented to our hospital with positive results for S. typhimurium, human rhinovirus, and Mycoplasma pneumoniae infections. At the time of admission to our institution, the patient's T helper 1/T helper 2 cytokine levels were 326 pg/mL for interleukin 6 (IL-6), 9.1 pg/mL for IL-10, and 246.7 pg/mL for interferon-gamma (IFN-γ), for which the ratio of IL-10 to IFN-γ was 0.04. In this study, the patient received meropenem, linezolid, and cefoperazone/sulbactam in combination with high-dose methylprednisolone therapy (10 mg/kg/d for 3 d) and antishock supportive treatment twice. After careful evaluation, this patient did not receive HLH chemotherapy and recovered well.

CONCLUSION

S. Typhimurium infection-triggered sHLH patient had a ratio of IL-10 to IFN-γ ≤ 1.33, an IL-10 concentration ≤ 10.0 pg/mL, and/or an IFN-γ concentration ≤ 225 pg/mL at admission. Early antimicrobial and supportive treatment was sufficient, and the HLH-94/2004 protocol was not necessary under these conditions.

An unusual presentation of subcutaneous panniculitis-like T-cell lymphoma: Extensive necrosis and hemophagocytic lymphohistiocytosis: A case report

Key Clinical message

Subcutaneous panniculitis-like T-cell lymphoma, a primary cutaneous lymphoma, which is described as following a slow course, could claim life. The occurrence of facial and breast nodules, the association with hemophagocytic lymphohistiocytosis, and the extent of necrosis and ulceration are signs of its aggressive nature needing early diagnosis and prompt treatment.

Abstract

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare skin disease that accounts for <1% of all peripheral T-cell lymphomas. It is described as following a slow and gradual process. However, it can be associated with a variety of clinical symptoms ranging from mild to severe. Hemophagocytic lymphohistiocytosis (HLH), a rare and potentially fatal hematologic factor that complicates SPTCL in 20% of cases, is an important prognostic factor. We report here an aggressive case of disseminated SPTCL with HLH involving a young woman who presented with extensive necrosis and ulceration at diagnosis. The report highlights the aggressive course of the disease, the occurrence of facial and breast nodules, the association with HLH, and the extent of necrosis and ulceration. The report highlights the poor prognosis despite polychemotherapy regimen use.

Prognostic factors in patients with secondary hemophagocytic lymphohistioc ytosis in a Chinese cohort

Hemophagocytic lymphohistiocytosis (HLH) is a rare hyperinflammatory syndrome with high mortality mediated by an unbridled and persistent activation of cytotoxic T lymphocytes and natural killer cells. However, the influence factors of early death in adult sHLH patients are still not fully elucidated, which need further investigating. We have conducted an observational study of adult HLH patients between January 2016 and December 2022. All patients are enrolled according to HLH-2004 criteria. Clinical manifestations, laboratory data, treatments, and outcomes have been recorded. Influence factors associated with prognosis are calculated by using logistic regression models. Overall, 220 patients enrolled in this study. The etiologies of HLH were divided into five groups including autoimmune-associated hemophagocytic syndrome (AAHS) (n = 90, 40.9%), malignancies (n = 73, 33.2%), EBV-HLH (n = 18, 8.2%), infection excluded EBV (n = 24, 10.9%), and other triggers (n = 15, 6.8%). Among them, EBV-HLH had the highest mortality (77.8%), and AAHS had the lowest mortality (14.4%). Multivariate analysis indicated that age (≥ 38 years old), cytopenia ≥ 2 lines, platelets (≤ 50 × 109/L), aspartate aminotransferase (≥ 135U/L), prothrombin time (≥ 14.9 s) and activated partial thromboplastin time (≥ 38.5s), EBV, and fungal infection are independent risk factors for poor prognosis of HLH. Adult HLH patients with elder age, cytopenia ≥ 2 lines, levels of decreased platelets, increased AST, prolonged PT and APTT, EBV, and fungal infection tend to have a poor prognosis.

A convenient and practical index for predicting the induction response in adult patients with hemophagocytic lymphohistiocytosis: ferritin/platelet ratio

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome with high mortality rate. The response to induction therapy is an important factor affecting survival. The purpose is to investigate laboratory predictors for induction response in adult patients with HLH, which are convenient, practical, and timeliness. Clinical data from January 2017 to December 2020 was retrospectively analyzed, and 269 patients were included. Patients were divided into remission and non-remission groups according to their induction response, 177 in the remission group, and 92 in the non-remission group. We reviewed general characteristics and analyzed the predictive value of serum ferritin, triglycerides, alanine aminotransferase (ALT), and blood cells before and 1-4 weeks after induction therapy for induction response by univariate analysis, ROC curves, etc. There was a correlation between serum ferritin, ALT, leukocytes, neutrophils, hemoglobin, platelets, and induction response (P < 0.05). Serum ferritin and platelets 1-4 weeks after induction therapy, respectively, might be a good predictor for induction response in adults with HLH, with AUC values close to or greater than 0.7. We established a new clinical model of the ferritin/platelet ratio. The results showed that the ferritin/platelet ratio at 1-4 weeks after induction therapy might be a practical index for predicting induction response, which significantly improved the area under the ROC curve (AUC > 0.75). Patients with a ferritin/platelet ratio > 16.08 at 2 weeks after induction therapy may have a relatively poor induction response. Ferritin/platelet ratio after induction therapy can be a good predictor for induction response in adult patients with HLH.

Hemophagocytic lymphohistiocytosis caused by herpes simplex virus type 1 in a young adult: a case report with literature review

Hemophagocytic lymphohistiocytosis is a severe hyperinflammatory syndrome that can be potentially life-threatening without appropriate treatment. Although viral infection is the most common trigger of hemophagocytic lymphohistiocytosis, cases of herpes simplex virus type 1-induced hemophagocytic lymphohistiocytosis are rare in adults. This study aims to provide a comprehensive overview of the clinical characteristics and treatment outcomes associated with HSV-1-induced HLH. We herein report an adult case of hemophagocytic lymphohistiocytosis caused by herpes simplex virus type 1, diagnosed on the basis of peripheral blood metagenomic next-generation sequencing results. The patient exhibited a favorable response to treatment, involving dexamethasone, intravenous immunoglobulin, and acyclovir. Notably, etoposide administration was deemed unnecessary, and there has been no recurrence of the disease within the year following treatment. Early and sensitive recognition, rapid and precise diagnosis, and timely and appropriate treatment facilitated the successful treatment of this case.

Filgrastim-induced hemophagocytic lymphohistiocytosis in a patient with mantle cell lymphoma: A case report

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease potentially induced by various causes. Very few reports have described HLH induced by granulocyte colony-stimulating factor (G-CSF) and those few previous reports have uniformly indicated that continuing G-CSF is unfeasible once HLH has been induced. A 52-year-old Japanese man who had been diagnosed with mantle cell lymphoma with systemic and central nervous system involvements received rituximab, hyper-fractionated cyclophosphamide, vincristine, Adriamycin and dexamethasone (R-HCVAD)/methotrexate and cytarabine. During the second cycle of R-HCVAD, the patient developed severe back pain, thrombocytopenia, elevated serum lactate dehydrogenase and ferritin levels, and hemophagocytosis in the bone marrow. Complete remission (CR) of mantle cell lymphoma was confirmed on whole-body computed tomography, brain magnetic resonance imaging, and bone marrow biopsy. The patient was diagnosed with HLH induced by filgrastim. HLH recovered with intravenous methylprednisolone at 1 g/day for 3 days, followed by oral prednisolone tapered off over 5 days. The patient continued chemotherapy with a change in the G-CSF formulation from filgrastim to lenograstim and prophylactic administration of corticosteroids. He safely completed scheduled chemotherapy without recurrence of HLH and successfully maintained CR of lymphoma. Although rare, G-CSF potentially induces HLH. Changing the G-CSF formulation and steroid prophylaxis may allow safe continuation of G-CSF.

Brain MRI imaging markers associated with death in children with central nervous system involvement of hemophagocytic lymphohistiocytosis

OBJECTIVES

To investigate the association of brain MRI and clinical variables with death in children with central nervous system involvement of hemophagocytic lymphohistiocytosis (CNS-HLH).

METHODS

Clinical and brain MRI data of children with CNS-HLH from January 2012 to March 2022 were reviewed retrospectively. Patients were divided into the deceased group and the surviving group. The intergroup differences of seven brain MRI variables, twelve clinical variables, and underlying diseases were studied.

RESULTS

One hundred and fourteen patients were included in this study, consisting of 59 who died and 55 who survived. The included clinical variables did not show statistically independent correlation with patients' deaths. For MRI variables, a multivariate analysis demonstrated restricted diffusion of lesion (OR = 9.64, 95% CI: 3.39-27.43, p < 0.001) and count of affected brain regions (CABR) (OR = 1.24, 95% CI: 1.03-1.49, p = 0.02) were independent risk factors for death. ROC curve showed CABR (AUC = 0.79, 95% CI: 0.70-0.87, p < 0.001) is highly predictive for mortality with an optimal cutoff value of 4.5 (sensitivity 76%, specificity 73%). For HLH subtypes, familial HLH (F-HLH, OR = 9.90, 95% CI: 2.01-48.87, p = 0.005) and immune-compromise-related HLH (IC-HLH, OR = 4.95, 95% CI: 1.40-17.46, p = 0.01) presented statistically stronger association with death than infection-related HLH. F-HLH and IC-HLH preferred to have large lesions, restricted diffusion, and more brain regions involved than other subtypes.

CONCLUSION

Brain MRI features exhibit independent prediction for mortality in children with CNS-HLH, and HLH subtypes pose effects on patient outcomes and brain MRI findings.

CLINICAL RELEVANCE STATEMENT

The number of affected brain regions and diffusion restriction of lesion exhibit significant correlation with mortality in children diagnosed with CNS-hemophagocytic lymphohistiocytosis, and may serve as candidate MRI markers for the prediction of the disorder's severity.

KEY POINTS

• The brain MRI markers, restricted diffusion of lesion and count of affected brain regions, significantly correlated with death. • Familial and immune-compromise-related hemophagocytic lymphohistiocytosis presented statistically stronger association with death than infection-related subtype. • Brain MRI is potential in death-predicting for children with central nervous system involvement of hemophagocytic lymphohistiocytosis.

The clinical significance and prognostic value of serum beta-2 microglobulin in adult lymphoma-associated hemophagocytic lymphohistiocytosis: a multicenter analysis of 326 patients

To investigate the prognostic impact of serum beta-2 microglobulin (B2M) in adult lymphoma-associated hemophagocytic lymphohistiocytosis (HLH). The clinical and laboratory characteristics of 326 adult patients in a multicenter cohort with lymphoma-associated HLH with available baseline serum B2M levels were retrospectively analyzed. A total of 326 cases were included in this study, and the median serum B2M level was 5.19 mg/L. The optimal cut-off of serum B2M was 8.73 mg/L, and the cases with serum B2M level >8.73 mg/L were older and had a more advanced stage, lower levels of platelets, albumin, and fibrinogen, and higher creatinine level. The serum B2M >8.73 mg/L, creatinine ≥133 μmol/L, fibrinogen ≤1.5 g/L, agranulocytosis (<0.5 × 109/L), severe thrombocytopenia (<50 × 109/L), and high Epstein-Barr virus DNA copy number were found to have independent prognostic values in all patients, and the serum B2M >8.73 mg/L was also an independent prognostic factor in patients with creatinine <133 μmol/L. Finally, a prognostic scoring system was established based on independent prognostic factors of all patients and categorized the patients into three groups with significant prognostic differences. This study confirmed that the serum B2M level can be an independent prognostic factor in lymphoma-associated HLH and established a prognostic scoring system to predict patients' survival.

X-Linked Lymphoproliferative Syndrome: A Spectrum of Clinical and Immunological Profile and Novel Pathogenic Variants from Chandigarh, India

INTRODUCTION

X-linked lymphoproliferative syndrome (XLP) is a rare primary immune deficiency. Two types of XLP have been described: XLP-1 and XLP-2.

METHODS

We found 7 patients with XLP (3 had XLP-1 and 4 had XLP-2) after reviewing the data from Pediatric Immunodeficiency Clinic from 1997 to 2021.

RESULTS

Mean age at diagnosis was 3.8 years, and mean delay in diagnosis was 2.6 years. Five patients had recurrent episodes of infections. Four patients developed at least one episode of hemophagocytic lymphohistiocytosis (HLH) (2 with XLP-1 and 2 with XLP-2). Of these, 2 had recurrent HLH (both with XLP-2). Epstein-Barr virus (EBV) infection was detected in 2 (1 with XLP-1 and 1 with XLP-2). Both these patients had HLH. One child with XLP-2 had inflammatory bowel disease. Hypogammaglobulinemia was seen in 3 (2 with XLP-1 and 1 with XLP-2). Genetic analysis showed previously reported variants in 5, while 2 had novel variants (one in exon 7 of XIAP gene [c.1370dup p.Asn457Lysfs Ter16] and other had splice site variant in intron 1 of SH2D1A gene [c.138-2_138-1insG]). Episodes of HLH were managed with intravenous immunoglobulin (IVIg), methylprednisolone, oral prednisolone, cyclosporine, and rituximab. Inflammatory bowel disease was managed using oral prednisolone and azathioprine. One patient underwent haploidentical hematopoietic stem cell transplantation. One child with XLP-2 and WAS died because of fulminant pneumonia.

DISCUSSION/CONCLUSIONS

XLP should be considered as a strong possibility in any patient with features of HLH, repeated infections with hypogammaglobulinemia, persistent EBV infection, and early-onset IBD.

Hemophagocytic lymphohistiocytosis following pembrolizumab and bevacizumab combination therapy for cervical cancer: a case report and systematic review

BACKGROUND

Programmed cell death protein 1 (PD-1) checkpoint inhibitors such as pembrolizumab are novel therapeutics used to treat various advanced malignancies. Immune-related adverse events are common, among the most serious of these toxicities is hemophagocytic lymphohistiocytosis (HLH), which is a life-threatening disorder of unbridled immune activation but has not been properly established.

METHODS

We have procured the first case of hemophagocytic lymphohistiocytosis as an aftermath of treatment with pembrolizumab from the Sir Run Run Shaw Hospital, Zhejiang University, China. In a pursuit to enhance the understanding of this condition, a comprehensive systematic review was performed encompassing all reported instances of ICI-associated Hemophagocytic lymphohistiocytosis within the realms of PubMed and Embase databases.

RESULTS

We detail the recovery of a cervical cancer patient with a history of psoriasis who developed HLH after combined pembrolizumab and bevacizumab treatment. Remarkably, tumor lesions exhibited substantial and sustained regression. From an analysis of 52 identified Immune Checkpoint Inhibitor (ICI)-related HLH cases, we discovered that HLH often occurred within the first two treatment cycles and approximately 20% of these patients had a history of autoimmune-related diseases. Despite a 15% mortality rate, the majority of patients experienced positive outcomes. Notably, in instances of recovery from HLH, 80% showed positive tumor outcomes. Even after discontinuation of ICI treatment, tumor control persisted in some cases.

CONCLUSION

We identified the first case of HLH caused by ICI treatment in cervical cancer and summarized the possible occurrence factors of these cases, the treatment outcomes of HLH, and the impact on tumor outcomes.

Pediatric hemophagocytic lymphohistiocytosis after concomitant administration of SARS-CoV-2 vaccine and influenza vaccine

Hemophagocytic lymphohistiocytosis (HLH) is a highly lethal disease characterized by fever, cytopenia, splenomegaly, and hemophagocytosis. Whereas infectious diseases, malignant tumors, and autoimmune diseases are often triggers for HLH, reports of HLH associated with vaccination are limited. In this report, we describe a case of HLH in a 12-year-old female patient after simultaneous administration of the bivalent messenger RNA severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine and quadrivalent inactivated influenza vaccine. The patient presented to our hospital with fever on the day after vaccination. Considering the splenomegaly, cytopenia, hemophagocytosis in the bone marrow, and high ferritin level, HLH was diagnosed 12 days after vaccination. Various tests ruled out any infectious disease, malignant tumor, or autoimmune disease. The patient was treated only with 2 mg/kg/day of oral prednisolone, fever improved 13 days after vaccination, and blood test findings rapidly improved. Although HLH after SARS-CoV-2 vaccination or concomitant administration with influenza vaccination is still rare, we emphasize the importance of early HLH diagnosis when persistent fever is observed following vaccination.

[Hemophagocytic lymphohistiocytosis: A retrospective analysis of 66 patients]

CONTEXT

Hemophagocytic lymphohistiocytosis is a rare syndrome with a poor prognosis, characterized by an uncontrolled dysregulation of the immune system. The rarity of this disease makes it difficult to obtain large cohorts. In this study, we analyzed the data of 66 patients: the objective was to describe the epidemiological, clinical, biological and therapeutic characteristics and to compare our results with those already published.

METHODS

We conducted a retrospective study at the University Hospital of Montpellier from 2015 to 2021. Patients were included when the diagnosis of HLH was mentioned on the hospitalization report and when the HSCORE was higher than 50% (169). Prognostic analyses were performed by comparing the patients who died from HMH to those who didn't.

RESULTS

The mean age the 66 patients included was 49.2 years, 62% were men. The percentage of deaths was 45.9%. Lymphoma was the main etiology, followed by infections, then autoimmune/autoinflammatory diseases. Fever, splenomegaly, hepatomegaly and organ failure were the main clinical manifestations. Pancytopenia was present in 62% of cases. Ferritin, triglycerides, LDH and AST were highly increased. Advanced age, associated lymphoma, and the severity of cytopenias were linked to a poor prognosis.

DISCUSSION

The study of the clinico-biological, epidemiological and survival data of the patients in our cohort allowed us to confirm previously published data but also to discuss some of them.

Hemophagocytic Lymphohistiocytosis Secondary to Refractory Acute Myeloid Leukemia Resolved after Second-Line Treatment with Azacitidine plus Venetoclax

Hemophagocytic lymphohistiocytosis (HLH), also defined as hemophagocytic syndrome (HPS), represents a potentially life-threatening hyperinflammatory syndrome, characterized by impaired function of cytotoxic T lymphocytes, natural killer cells and macrophages. The main clinical features of HLH are prolonged fever, hepatosplenomegaly, cytopenia, hypertriglyceridemia, hyperferritinemia and hemophagocytosis in bone marrow, liver, spleen or lymph nodes. Secondary HLH typically occurs in conjunction with severe infections, malignancies or autoimmune disorders and intensive chemotherapy, potentially complicating treatment of acute myeloid leukemia (AML) in around 10% of cases. Herein we report for the first time a case of HLH secondary to refractory/relapsed AML resolved after a second line treatment with azacitidine plus venetoclax, thus offering a new potential therapeutic perspective in the context of a life-threatening clinical scenario.

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.

Fatal COVID-19 Infection in Two Children with STAT1 Gain-of-Function

While SARS-CoV-2 infection causes a mild disease in most children, SARS-CoV-2 infection may be lethal in a few of them. In the defense against SARS-CoV-2, type I interferons are key players, and several studies have identified a defective or neutralized interferon response as the cause of overwhelming viral infection. However, inappropriate, untimely, or excessive interferon production may also be detrimental to the host. Here, we describe two patients with STAT1 gain-of-function (GOF), a known type I interferonopathy, who died of COVID-19. Whole-exome sequencing and interferon-gamma-activated sequence (GAS) and interferon-sensitive responsive element (ISRE) reporter assay were performed to identify and characterize STAT1 variants. Patient 1 developed hemophagocytic lymphohistiocytosis (HLH) in the context of COVID-19 infection and died in less than a week at the age of 4 years. Patient 2 developed a high fever, cough, and hypoxemia and succumbed to COVID-19 pneumonia at the age of 5 years. Two heterozygous missense variants, p.E563Q and p.K344E, in STAT1 were identified. Functional validation by reporter assay and immunoblot confirmed that both variants are gain-of-function (GOF). GOF variants transiently expressing cells exhibited enhanced upregulation of downstream genes, including ISG15, MX1, and OAS1, in response to IFN-α stimulation. A catastrophic course with HLH or acute respiratory failure is thought to be associated with inappropriate immunoregulatory mechanisms to handle SARS-CoV-2 in STAT1 GOF. While most patients with inborn errors of immunity who developed COVID-19 seem to handle it well, these cases suggest that patients with STAT1-GOF might be at risk of developing fatal complications due to SARS-CoV-2.

A variant of KSHV-associated inflammatory cytokine syndrome in elderly men of Mediterranean descent

The spectrum of HHV-8-associated disorders includes Kaposi's sarcoma, primary effusion lymphoma, multicentric Castleman's disease, and the recently described KSHV inflammatory cytokine syndrome (KICS), a life-threatening disorder complicating HIV infection. There have been no reports in the literature concerning non-immunosuppressed individuals affected with KICS. We report here a KICS-like illness occurring in two elderly Greek men without HIV infection or other recognizable cause of immunosuppression.

[Clinical characteristics and diagnostic indicators of macrophage activation syndrome in patients with systemic lupus erythematosus and adult-onset Still's disease]

OBJECTIVE

To analyze and compare the clinical and laboratory characteristics of macrophage activation syndrome (MAS) in patients with systemic lupus erythematosus (SLE) and adult-onset Still's disease (AOSD), and to evaluate the applicability of the 2016 European League Against Rheumatism/American College of Rheumatology/Paediatric Rheumatology International Trials Organization classification criteria for MAS complicating systemic juvenile idiopathic arthritis (sJIA) in different auto-immune diseases contexts and to propose new diagnostic predictive indicators.

METHODS

A retrospective analysis was conducted on the clinical and laboratory data of 24 SLE patients with MAS (SLE-MAS) and 24 AOSD patients with MAS (AOSD-MAS) who were hospitalized at Peking University People's Hospital between 2000 and 2018. Age- and sex-matched SLE (50 patients) and AOSD (50 patients) diagnosed in the same period without MAS episodes were selected as controls. The cutoff values for laboratory indicators predicting SLE-MAS and AOSD-MAS were determined using receiver operating characteristic (ROC) curves. Furthermore, the laboratory diagnostic predictive values for AOSD-MAS were used to improve the classification criteria for systemic juvenile idiopathic arthritis-associated MAS (sJIA-MAS), and the applicability of the revised criteria for AOSD-MAS was explored.

RESULTS

Approximately 60% of SLE-MAS and 40% of AOSD-MAS occurred within three months after the diagnosis of the underlying diseases. The most frequent clinical feature was fever. In addition to the indicators mentioned in the diagnosis criteria for hemophagocytic syndrome revised by the International Society for Stem Cell Research, the MAS patients also exhibited significantly elevated levels of aspartate aminotransferase and lactate dehydrogenase, along with a significant decrease in albumin. Hemophagocytosis was observed in only about half of the MAS patients. ROC curve analysis demonstrated that the optimal discriminative values for diagnosing MAS was achieved when SLE patients had ferritin level≥1 010 μg/L and lactate dehydroge-nase levels≥359 U/L, while AOSD patients had fibrinogen levels≤225.5 mg/dL and triglyceride levels≥2.0 mmol/L. Applying the 2016 sJIA-MAS classification criteria to AOSD-MAS yielded a diagnostic sensitivity of 100% and specificity of 62%. By replacing the less specific markers ferritin and fibrinogen in the 2016 sJIA-MAS classification criteria with new cutoff values, the revised criteria for classifying AOSD-MAS had a notable increased specificity of 86%.

CONCLUSION

Secondary MAS commonly occurs in the early stages following the diagnosis of SLE and AOSD. There are notable variations in laboratory indicators among different underlying diseases, which may lead to misdiagnosis or missed diagnosis when using uniform classification criteria for MAS. The 2016 sJIA-MAS classification criteria exhibit high sensitivity but low specificity in diagnosing AOSD-MAS. Modification of the criteria can enhance its specificity.

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.

A case of hepatosplenic cat scratch disease with hemophagocytic lymphohistiocytosis

Cat scratch disease (CSD) is associated with Bartonella henselae (B. henselae) infection caused by cat scratches or bites. It typically presents with lymphadenitis and fever. However, there are atypical cases such as hepatosplenic CSD, which presents with specific lesions in the liver and spleen. Hemophagocytic lymphohistiocytosis (HLH) is a rare and severe multisystem disorder triggered by infections, cancers, or autoimmune diseases. We experienced a rare case of hepatosplenic CSD with HLH in a non-immunocompromised adult. A 78-year-old woman complained of fever and fatigue. Laboratory tests revealed anemia and liver dysfunction; abdominal contrast-enhanced computed tomography (CT) revealed splenomegaly and nodular hypodense areas in the spleen. In addition, the levels of ferritin and serum soluble IL-2R were markedly elevated, so clinical diagnosis of HLH was made. Positron emission tomography/CT revealed diffuse fluorodeoxyglucose uptake in the liver and spleen suggesting malignant lymphoma, while the pathological findings from liver biopsy suggested infectious diseases. Although she had no cat bites and scratches, she had many cats; therefore, serum B. henselae antibody titers were measured. The B. henselae IgG and IgM titer were 1:128 and 1:20; thus, she was diagnosed with hepatosplenic CSD. Patients with hepatosplenic nodular lesions and contact with cats should be considered for this disease.

Suspect the Unexpected: A Rare Association of Autoimmune Hemolytic Anemia and Hemophagocytic Lymphohistiocytosis with Visceral Leishmaniasis: A Case Report and Review of Literature

Visceral leishmaniasis is a common tropical infection presenting with a myriad of hematological abnormalities. We report an unusual case of an 11-year-old girl suffering from a febrile illness with hepatosplenomegaly and anemia. Laboratory findings included pancytopenia and hyperbilirubinemia. The leishmania antigen rK39 was positive and bone marrow examination revealed hemophagocytosis and amastigote forms of Leishmania donovani. Direct Coombs' test was positive (warm type, IgG) and LDH was elevated. Tests for other infections were negative. A diagnosis of visceral leishmaniasis with autoimmune hemolytic anemia (warm antibody type, IgG) with hemophagocytic lymphohistiocytosis was made. Patient showed response with anti-leishmanial treatment with improvement in clinical condition.

Severe acute herpes virus type 2 primo-infection and its association with anti-type 1 interferon autoantibodies

Herpes simplex virus type 2 (HSV-2) is a common cause of infection, which is usually self-limited and asymptomatic. A 71-year-old patient with HSV-2 primo-infection developed acute hepatitis and secondary hemophagocytic lymphohistiocytosis. The patient had high levels of autoantibodies against type I interferon (IFN) (> 1000 ng/mL), neutralizing high concentration (10 ng/mL) of both IFN-α and IFN-ω but not IFN-β. Anti-IFN-I auto-antibodies are rarely observed in healthy individuals; however, their prevalence increases in individuals over 70 years of age and have been identified as a cause of some severe viral diseases, including critical COVID-19. Considering the function of IFN-I in innate immunity, the pathological role of these autoantibodies in severe viral diseases following primo-infections in elderly patient appears crucial.

Macrophage depletion using clodronate liposomes reveals latent dysfunction of the hematopoietic microenvironment associated with persistently imbalanced M1/M2 macrophage polarization in a mouse model of hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH), a hyperinflammatory syndrome, is caused by the incessant activation of lymphocytes and macrophages, resulting in damage to organs, including hematopoietic organs. Recently, we demonstrated that repeated lipopolysaccharide (LPS) treatment induces HLH-like features in senescence-accelerated (SAMP1/TA-1) mice but not in senescence-resistant control (SAMR1) mice. Hematopoietic failure in LPS-treated SAMP1/TA-1 mice was attributed to hematopoietic microenvironment dysfunction, concomitant with severely imbalanced M1 and M2 macrophage polarization. Macrophages are a major component of the bone marrow (BM) hematopoietic microenvironment. Clodronate liposomes are useful tools for in vivo macrophage depletion. In this study, we depleted macrophages using clodronate liposomes to determine their role in the hematopoietic microenvironment in SAMP1/TA-1 and SAMR1 mice. Under clodronate liposome treatment, the response between SAMR1 and SAMP1/TA-1 mice differed as follows: (1) increase in the number of activated M1 and M2 macrophages derived from newly generated macrophages and M2-dominant and imbalanced M1 and M2 macrophage polarization in the BM and spleen; (2) severe anemia and thrombocytopenia; (3) high mortality rate; (4) decrease in erythroid progenitors and B cell progenitors in the BM; and (5) decrease in the mRNA expression of erythroid-positive regulators such as erythropoietin and increase in that of erythroid- and B lymphoid-negative regulators such as interferon-γ in the BM. Depletion of residual macrophages in SAMP1/TA-1 mice impaired hematopoietic homeostasis, particularly erythropoiesis and B lymphopoiesis, owing to functional impairment of the hematopoietic microenvironment accompanied by persistently imbalanced M1/M2 polarization. Thus, macrophages play a vital role in regulating the hematopoietic microenvironment to maintain homeostasis.

Subcutaneous panniculitis-like T-cell lymphoma associated with hemophagocytic lymphohistiocytosis: a systematic review of 63 patients reported in the literature

To review and summarize the clinical features, treatment strategies, and prognosis of subcutaneous panniculitis-like T-cell lymphoma complicated with hemophagocytic lymphohistiocytosis (SPTCL-HLH). We searched the Web of Science, Embase, Cochrane Library, and PubMed databases. The keywords were subcutaneous panniculitis-like T-cell lymphoma and hemophagocytic lymphohistiocytosis or hemophagocytic syndrome. The patients were divided into a mutated group and a wild-type group based on the existence of HAVCR2 gene mutation. A total of 45 reports, including 63 patients with SPTCL-HLH, were included in the systematic review. Twelve patients detected gene mutations, including 11 with the HAVCR2 gene mutation and 1 with the STXBP2 gene mutation. Thirty-one patients were tested for autoantibodies. Compared with the wild-type group, patients in the mutated group were younger (p = 0.017), and the autoantibody-positive rate was higher (p = 0.006). The main treatment target of 17 patients was to control HLH, yielding an ORR of 88.2%. Two cases relapsed, and both were treated with corticosteroid monotherapy. The corticosteroid monotherapy experienced a higher recurrence rate than the corticosteroids plus other immunoregulatory agents therapy (66.7 vs. 0.0%, p = 0.029). Eighteen patients received initial anthracycline-based chemotherapy, and 50.0% reached remission. The ORR of initial chemotherapy aiming at controlling HLH was higher than those of anthracycline-based chemotherapy (p = 0.015). The ORR was higher in patients initially controlled for HLH versus chemotherapy without HLH control first (90.5 vs. 61.5%, p = 0.024). Interestingly, one patient with juvenile idiopathic arthritis developed SPTCL-HLH during tocilizumab therapy, discontinuing tocilizumab led to a remission of the disease spontaneously. Sixteen patients received stem cell transplantation (SCT). Fifteen patients, including 5 with relapsed/refractory SPTCL-HLH, responded well and survived after receiving SCT. One case who received a sibling-identical SCT relapsed. Further analysis revealed a homozygous HAVCR2 mutation with the donor. The 2-year overall survival (OS) was 91.0% ± 4.4%. There was a significant difference in the OS among patients of different age groups, and patients aged 40-60 had the lowest 2-year OS (66.7% ± 19.2%). Patients with HAVCR2 gene mutations are younger and more likely to be misdiagnosed with autoimmune diseases. Initial treatment of corticosteroids plus immunoregulatory agents attaches great significance to avoiding too aggressive therapies. Intensive anthracycline-based chemotherapy such as CHOP or CHOP-like regimens can also induce long-term remission for aggressive disease. SCT is still a reliable strategy currently. In addition, a watch and wait approach is recommended in patients with mild SPTCL-HLH caused by drugs. The occurrence of HLH does not necessarily mean a more rapidly progressive disease and worse prognosis in patients with SPTCL, but older patients with SPTCL-HLH may be associated with a lower survival rate.

Clinical characteristics, treatment, and management of pembrolizumab induced hemophagocytic lymphohistiocytosis

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare and fatal adverse reaction to pembrolizumab. The clinical characteristics of pembrolizumab induced HLH are unknown. Exploring the clinical features of pembrolizumab induced HLH is crucial for the treatment and prevention of immune checkpoint inhibitor-induced HLH.

METHODS

The literature related to pembrolizumab induced HLH was collected for retrospective analysis by searching the Chinese and English databases from inception until August 31, 2023.

RESULTS

A total of 24 patients were included, including 17 men (70.8%) with a median age of 61 years (41,80). The time between the last infusion and the start of HLH ranged from 2 to 46 days, with a median time of 14 days. Fever (100%) was the most common symptom, accompanied by splenomegaly (14 cases, 58.3%) and hepatomegaly (6 cases, 25.0%). Laboratory examination revealed revealed anemia (18 cases, 75.0%), leukopenia (12 cases, 50.0%), thrombocytopenia (20 cases, 83.3%), hypertriglyceridemia (11 cases, 45.8%), hypofibrinogenemia (11 cases, 45.8%). decreased natural killer cell function (7 cases, 29.2%), and elevated soluble CD25(15 cases, 62.5%). All patients developed hyperferriinemia, with a median of 30,808 ng/mL (range 1303 ~ 100,000). Bone marrow biopsy showed hemophagocytosis (15 cases, 62.5%). After discontinuation of pembrolizumab and treatment with steroids, etoposide, intravenous immunoglobulin, cytokine blocking, and immunosuppression, 17 patients recovered or improved, and 5 patients eventually died.

CONCLUSION

HLH should be suspected when unexplained fever, cytopenia, splenomegaly, and elevated aminotransferase occur in patients using pembrolizumab. Screening for risk factors before treatment with pembrolizumab may be necessary to prevent HLH.

An analysis of sintilimab combined with ruxolitinib as compassionate therapy for 12 adults with EBV-associated hemophagocytic lymphohistiocytosis

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) is a severe hyperinflammatory illness that affects adults and is caused by an EBV infection. Without allogeneic hematopoietic stem cell transplantation (allo-HSCT), the overall survival of adult patients with EBV-HLH is unsatisfactory, necessitating the development of innovative therapeutic approaches. The clinical records of twelve EBV-HLH patients who received sintilimab therapy combined with ruxolitinib on a compassionate basis at the First Affiliated Hospital of Soochow University were retrospectively examined in this investigation. All the patients responded without fever, but three patients relapsed within a week. Among the nine patients achieving complete response (CR), 55.6% (5/9) maintained CR for >4.5 months, and 33.3% (3/9) relapsed following CR. Neither patients with no response (NR) nor relapsed patients were fit for allo-HSCT, and all died soon after discharge. Six patients had clinical CR with a median follow-up of 5 (4.4-14.7) months. There were no documented severe negative effects. Additional information on this innovative treatment for adult EBV-HLH is provided in our report.

Asian variant intravascular large B-cell lymphoma with highly suspected central nervous system involvement: A case report

BACKGROUND

Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of extranodal lymphoma. In particular, the Asian variant of IVLBCL is characterized by hemophagocytic lymphohistiocytosis along with bone marrow involvement. However, central nervous system (CNS) involvement is uncommon in this variant compared to the Western variant. Here, we report a case of typical Asian variant IVLBCL with highly suspected CNS involvement and discuss the nature of the disease and its genetic aberration.

CASE SUMMARY

A 67-year-old female patient complained of gradually worsening cognitive impairment. While hospitalized, she developed a high fever and showed marked bicytopenia. Intracranial imaging revealed a suspected leptomeningeal disease. Although no malignant cells were found in the cerebrospinal fluid (CSF), the protein and lactate dehydrogenase levels in CSF were increased. Bone marrow examination revealed an increased number of hemophagocytic histiocytes, and ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography with computerized tomography scan revealed increased FDG uptake in both adrenal glands, the liver, and the right ethmoid sinus. A tissue biopsy showed atypical large lymphoid cells with prominent nucleoli in the vessels, and the tumor cells were positive for CD20, BCL2, BCL6, and IRF4/MUM1. In addition, targeted sequencing identified MYD88, TET2, and PIM1 mutations. Consequently, we diagnosed the patient with the Asian variant of IVLBCL with highly suspected CNS involvement.

CONCLUSION

Suspicion of IVLBCL and immediate diagnosis lead to timely treatment. Moreover, careful CNS examination at diagnosis is recommended.

A rare case of orbital inflammation complicated by hemophagocytic lymphohistiocytosis

We report a rare case of orbital inflammation complicating hemophagocytic lymphohistiocytosis (HLH) patient. HLH is a rare, life-threatening disorder characterized by uncontrolled activation of cytotoxic T lymphocytes, natural killer cells, and macrophages. A 37-year-old man known to have HLH, presented with a left periorbital swelling that was unsuccessfully treated as an orbital cellulitis, with intravenous antibiotics. A computed tomography (CT) scan of the orbits revealed inflammatory changes with no orbital collection or paranasal sinus disease. An orbital biopsy demonstrated lymphoplasmacytic infiltrations admixed with histiocytes. The patient deteriorated and was admitted to the intensive care unit. Ensuing blood results supported a diagnosis of HLH, and the patient responded well to subsequent immunosuppression. This case report highlights the importance of re-considering the diagnosis of orbital cellulitis in treatment resistant cases, particularly in the absence of sinus disease. To our knowledge, this is the third case of orbital inflammation associated with HLH patients.

Performances of the H-score and the HLH-2004 score in the positive diagnosis of secondary hemophagocytic lymphohistiocytosis

Hemophagocytic lymphocytosis (HLH) is a rare clinical and biological entity that can be life-threatening. Early diagnosis can improve the overall prognosis of HLH.

OBJECTIVES

The aims of this study are to evaluate the performances of HLH-2004-score and H-score in identifying patients with secondary HLH and to determine an optimal H-score cut-off for our population.

METHODS

A retrospective study that involved all patients, with images of hemophagocytosis in myelograms analyzed at the laboratory of hematology, followed at these departments: clinical-hematology, internal-medicine, infectious-diseases and gastroenterology, University-Hospital "Hédi-Chaker", Sfax-Tunisia, (June2017-May2021). We identified two groups of patients: "HLH" and "Not-HLH". Then, for each patient, we calculated the HLH-2004-score and the H-score.

RESULTS

Forty-two patients were included in this study. Twenty-five (60 %) belonging to group "HLH" and seventeen (40 %) to group "Not-HLH" with a mean age (38.72 vs. 39.82 years, p = 0.846) respectively. The study of the performances demonstrated that H-score had better performances. The best cut-off value of H-score for our population was 158.5, allowing a gain in sensitivity (from 92 % to 96 %) compared to the original study cut-off of 169.

CONCLUSION

Both H-score and HLH-2004-score showed excellent discriminative powers with better performances for H-score. The new H-score cut-off at 158.5 can be applied to our population.

Late-onset Familial Hemophagocytic Lymphohistiocytosis in a survivor of Hodgkin's Lymphoma

Hemophagocytic Lymphohistiocytosis is an inflammatory condition which results in over activation of the immune system. It could be either sporadic or familial. The familial subtype is linked with various genetic mutations and is commonly a disease of the young. Here we report a case of HLH in an adult, occurring in the background of a successfully treated hematological malignancy. Upon workup, he was also found to have pathogenic STXBP2 mutation, suggesting HLH of familial origin. To date, only few cases of adult-onset familial HLH have been brought to light.

A novel prognosis-prediction model based on coagulation indicators in secondary hemophagocytic lymphohistiocytosis

Secondary hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease. In the present retrospective study, we aimed to investigate coagulation disorders and their outcome implications in patients with secondary HLH. We evaluated clinical characteristics and the relationship between coagulation indices and prognosis in HLH patients (n = 141). The information, including clinical symptoms, laboratory indicators, and coagulation indices, was evaluated. Coagulation disorders and bleeding events occurred in 95 (67.4%) and 60 (42.6%) patients, respectively. A coagulation index analysis primarily showed elevated levels of D-Dimer, the international standardized ratio (INR), prothrombin time (PT), activated partial thromboplastin time (APTT), and thrombin time (TT), while the prothrombin activity, fibrinogen levels, and platelet levels were significantly decreased. Dominant disseminated intravascular coagulation (DIC) occurred in 76 patients (53.9%). Patients with lymphoma-associated hemophagocytic syndrome (LAHS) frequently exhibited apparent coagulation disorders. Multivariate analysis revealed that age ≥ 29.5 years, bleeding events, APTT ≥ 47.3 s, fibrinogen ≤ 1.68 g/L, and absolute neutrophil counts (ANC) of ≤ 1.21 × 109/L were independent prognostic factors. We thereby devised a prognostic scoring system and stratified patients into low-risk (0-2 points), intermediate-risk (3-4 points), and high-risk (5-7 points) groups, and the 1-year overall survival rates in the above-mentioned groups were 66.40%, 40.00%, and 2.30%, respectively (P < 0.0001). In conclusion, coagulation dysfunctions and bleeding tendencies were common characteristics in HLH patients. We constructed a novel prognostic score model based on APTT, fibrinogen level, ANC, age, and bleeding events, which had superior prognostic value compared with these markers alone.

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

BACKGROUND

Secondary hemophagocytic lymphohistiocytosis (sHLH) is a rare but fatal clinical syndrome, characterized by severe immune dysfunction and overwhelming inflammatory response. However, the host immune signature and also its role in predicting the clinical outcome are not fully described.

OBJECTIVE

The present study aims to investigate the host immune status of sHLH patients in the early stage of the disease, including lymphocyte subsets, phenotypes and cytokines, and also to explore its clinical value in prognosis.

METHODS

Sixty-four patients with sHLH admitted to a tertiary hospital in central China between 2018 and 2022 were enrolled, of which 21 were deceased. The subsets and phenotypes of lymphocytes, and the levels of cytokines in serum were analyzed.

RESULTS

In patients with sHLH, the percentages of total T cells, CD8+ T cells, HLA-DR+ T cells, HLA-DR+CD8+ T cells, CD45RO+CD4+ T cells, and the levels of IL-1β, IL-2R, IL-6, IL-8, IL-10 and TNF-α were significantly increased, while the percentages of CD4+ T cells, NK cells, CD45RA+CD4+ T cells, CD45RA+ regulatory T (Treg) cells, the counts of total T cells, total B cells, CD4+ T cells, CD8+ T cells, NK cells, and the ratio of CD4+ T/CD8+ T cells were significantly decreased, compared with healthy controls (HC). In addition, dysregulation of host immune response and high inflammatory status were more obvious in deceased patients than that of survivors. Kaplan-Meier survival analysis and multivariate logistic regression analysis demonstrated that lower levels of CD4+ T cells count and CD28+CD4+ T cells percentage, but higher levels of NK cells percentage and IL-1β were poor prognostic indicators of sHLH.

CONCLUSION

The evaluation of immunological markers has critical value for selecting prognostic markers and potential treatment target among adults with sHLH.