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.

[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.

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.