Familial hemophagocytic lymphohistiocytosis. Primary hemophagocytic lymphohistiocytosis

The pathophysiology and current treatments for the subcutaneous panniculitis-like T cell lymphoma: An updated review

Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a rare cutaneous T cell lymphoma, which is indolent in nature but could claim life if not correctly diagnosed and promptly treated. SPTCL is usually presented clinically as painless subcutaneous and erythematous nodules over the trunk or extremities. Active clinical vigilance for these subcutaneous nodules or panniculitis-like lesions is warranted. A biopsy must be performed in order to make a correct diagnosis. Positron emission tomography scan is utilized for disease staging and treatment follow-up. Due to the rarity of this lymphoma, a standard treatment protocol is not established yet. However, most cases of SPTCL could be treated well under immunosuppressive or polychemotherapeutic drugs except in cases with hemophagocytic syndrome. Hematopoietic stem cell transplantation may be used in refractory or relapse cases. In this review, we presented a case of SPTCL with long-term complete remission. Meanwhile, since most clinical evidences and experiences of SPTCL are based mostly on case reports or small case series, and the understanding of the SPTCL pathophysiology is limited, we reviewed and updated the pathophysiology and treatments of SPTCL.

Hemophagocytic lymphohistiocytosis as an etiology of bone marrow failure

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of multiorgan system dysfunction that is caused by hypercytokinemia and persistent activation of cytotoxic T lymphocytes and macrophages. A nearly ubiquitous finding and a diagnostic criterion of HLH is the presence of cytopenias in ≥ 2 cell lines. The mechanism of cytopenias in HLH is multifactorial but appears to be predominantly driven by suppression of hematopoiesis by pro-inflammatory cytokines and, to some extent, by consumptive hemophagocytosis. Recognition of cytopenias as a manifestation of HLH is an important consideration for patients with bone marrow failure of unclear etiology.

Matrin3 (MATR3) Expression Is Associated with Hemophagocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome characterized by prolonged fever, cytopenia, hepatosplenomegaly, and hemophagocytosis. This occurs as a result of activated macrophages and impaired function of natural killer cells and/or cytotoxic T lymphocytes. The NF-κB pathway plays a crucial role in hyperinflammation. Matrin3 (MATR3) is a nuclear RNA/DNA-binding protein that plays multiple roles in the regulation of gene expression. We enroll 62 patients diagnosed with secondary HLH and hemophagocytosis. Peripheral blood (PB) from 25 patients and 30 healthy volunteers and good quality bone marrow (BM) samples from 47 patients are collected and used for analysis. Clinical parameters, including age, sex, etiology, ferritin, fibrinogen, triglyceride, and viral infection status, had no association with survival prediction. Patients with downregulation of NF-κB and MATR3mRNA expression in the BM had a higher mortality rate. MATR3mRNA expression in PB was lower in patients compared to that in healthy volunteers. We use shRNA-MATR3-KD-THP1 cells to determine the efficacy of phagocytosis. We note that shRNA-MATR3-KD-THP1 cells had a higher phagocytic effect on necrotic Jurkat E6 cells and carboxylate modified polystyrene latex beads. Herein, we provide evidence of a new marker for clinical translation that can serve as a potential treatment target for secondary HLH.

Hemophagocytic Lymphohistiocytosis Associated With Hemolytic Uremic Syndrome in a Child: A Case Report and Systematic Literature Review

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disorder resulting from excessive activation and nonmalignant proliferation of T-lymphocytes and macrophages. Hemolytic uremic syndrome (HUS) is a disease characterized by microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. Reports pertaining to the association between HLH and HUS are rarely published; however, we report on a 4-year-old boy who was diagnosed with both conditions and treated successfully with high-dose steroid and intravenous immunoglobulin. Differentiating HUS from HLH can be challenging because of their clinical similarities. Therefore, prompt diagnosis and immunosuppressive treatment are essential and life-saving to these patients.

RhoG's Role in T Cell Activation and Function

The role of RhoG in T cell development is redundant with other Racs subfamily members, and this redundancy may be attributed to redundant signal transduction pathways. However, the absence of RhoG increases TCR signalling and proliferation, implying that RhoG activity is critical during late T cell activation following antigen–receptor interaction. Moreover, RhoG is required to halt signal transduction and prevent hyper-activated T cells. Despite increase in TCR signalling, cell proliferation is inhibited, implying that RhoG induces T cell anergy by promoting the activities of transcription factors, including nuclear factor of activated T cell (NFAT)/AP-1. The role of NFAT plays in T cell anergy is inducing the transcription of anergy-associated genes, such as IL-2, IL-5, and IFN-γ. Although information about RhoG in T cell-related diseases is limited, mutant forms of RhoG, Ala151Ser and Glu171Lys have been observed in thymoma and hemophagocytic lymphohistiocytosis (HLH), respectively. Current information only focuses on these two diseases, and thus the role of RhoG in normal and pathological circumstances should be further investigated. This approach is necessary because RhoG and its associated proteins represent prospective targets for attack particularly in the therapy of cancer and immune-mediated illnesses.

Pediatric isoniazid-resistant tuberculosis of the bone marrow manifesting as hemophagocytic syndrome: A case report

Hemophagocytic syndrome (HPS) is a critical syndrome of ineffective hyperinflammatory immune response resulting in infiltration of lymphocytes and histiocytes in various organs. Causes can be hereditary or due to malignancy, autoimmune disease, or infection. HPS due to Mycobacterium tuberculosis is rare as only a handful of cases are reported, and they are mostly associated with severe disseminated tuberculosis (TB). We reported a 9-year-old boy with tuberculosis of the bone marrow accompanied with hemophagocytic syndrome. The patient presented with manifestation of HPS and had no respiratory symptoms or risk factors for TB but was later diagnosed of isoniazid-resistant TB in the bone marrow. He had a good outcome after receiving anti-TB drugs and corticosteroids on time. This case highlights that bone marrow might be a shelter for Mycobacterium tuberculosis. Concurrent testing for drug susceptibility in TB cases with an uncommon manifestation is recommended even for first episodes. Early diagnosis and etiological confirmation of the infection origin and appropriate treatment are essential to improve survival in this otherwise life-threatening condition.

Digenic Inheritance: Evidence and Gaps in Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory disorder characterized by the inability to properly terminate an immune response. Familial HLH (FHLH) and related immune dysregulation syndromes are associated with mutations in the genes PRF1, UNC13D, STX11, STXBP2, LYST, AP3B1, and RAB27A, all of which are required for the assembly, exocytosis, and function of cytotoxic granules within CD8+ T cells and natural killer (NK) cells. Loss-of-function mutations in these genes render the cytotoxicity pathway ineffective, thereby failing to eradicate immune stimuli, such as infectious pathogens or malignant cells. The resulting persistent immune system stimulation drives hypercytokinemia, ultimately leading to severe tissue inflammation and end-organ damage. Traditionally, a diagnosis of FHLH requires the identification of biallelic loss-of-function mutations in one of these degranulation pathway genes. However, this narrow definition fails to encompass patients with other genetic mechanisms underlying degranulation pathway dysfunction. In particular, mounting clinical evidence supports a potential digenic mode of inheritance of FHLH in which single loss-of-function mutations in two different degranulation pathway genes cooperate to impair pathway activity. Here, we review the functions of the FHLH-associated genes within the degranulation pathway and summarize clinical evidence supporting a model in which cumulative defects along this mechanistic pathway may underlie HLH.

Molecular Genetics Diversity of Primary Hemophagocytic Lymphohistiocytosis among Polish Pediatric Patients

Hemophagocytic lymphohistiocytosis (HLH) is a clinical syndrome of life-threatening inflammation caused by an excessive, prolonged and ineffective immune response. An increasing number of HLH cases is recognized in Poland, but the genetic causes of familial HLH (FHL) have not been reported. We investigated the molecular genetics and associated outcomes of pediatric patients who met HLH criteria. We studied 54 patients with HLH, 36 of whom received genetic studies. Twenty-five patients were subjected to direct sequencing of the PRF1, UNC13D, STX11, XIAP and SH2D1A genes. Additionally, 11 patients were subjected to targeted next-generation sequencing. In our study group, 17 patients (31%) were diagnosed with primary HLH, with bi-allelic FHL variants identified in 13 (36%) patients whereas hemizygous changes were identified in 4 patients with X-linked lymphoproliferative diseases. In addition, one patient was diagnosed with X-linked immunodeficiency with magnesium defect, Epstein–Barr virus infection and neoplasia due to a hemizygous MAGT1 variant; another newborn was diagnosed with auto-inflammatory syndrome caused by MVK variants. The majority (65%) of FHL patients carried UNC13D pathogenic variants, whereas PRF1 variants occurred in two patients. Novel variants in UNC13D, PRF1 and XIAP were detected. Epstein–Barr virus was the most common trigger noted in 23 (65%) of the patients with secondary HLH. In three patients with secondary HLH, heterozygous variants of FHL genes were found. Overall survival for the entire study group was 74% with a median of 3.6 years of follow-up. Our results highlight the diversity of molecular causes of primary HLH in Poland.

Genetic and clinical characteristics of pediatric patients with familial hemophagocytic lymphohistiocytosis

Background

Our study was designed to investigate the frequencies and distributions of familial hemophagocytic lymphohistiocytosis (FHL) associated genes in Saudi patients.

Methods

FHL associated gene screening was performed on 87 Saudi patients who were diagnosed with hemophagocytic lymphohistiocytosis (HLH) between 1995 and 2014. The clinical and biochemical profiles were also retrospectively captured and analyzed.

Results

Homozygous mutations and mono-allelic variants were identified in 66 (75.9%) and 3 (3.5%) of the study participants, respectively. STXBP2 was the most frequently mutated gene (36% of patients) and mutations in STXBP2 and STX11 accounted for 58% of all FHL cases and demonstrated a specific geographical pattern. Patients in the FHL group presented at a significantly younger age than those belonging to the unknown-genetics group (median, 3.9 vs. 9.4 mo; P=0.005). The presenting clinical features were similar among the various genetic groups and the 5-year overall survival (OS) was 55.4% with a 5.6 year median follow-up. Patients with PRF1 mutations had a significantly poorer 5-year OS (21.4%, P=0.008) and patients undergoing hematopoietic stem cell transplant (72.4%) had a significantly better 5-year OS (66.5% vs. 0%, P=0.001).

Conclusion

Our study revealed the predominance of the STXBP2 mutations in Saudi patients with FHL. A genetic diagnosis was possible in 80% of the cohort and our data showed improved survival in FHL patients who underwent hematopoietic stem cell transplant.

Performance of HScore in Reactive Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a life threatening systemic hyperinflammatory disorder that leads to multiple organ damage. The most widely used diagnostic guidelines are the HLH 2004 guidelines proposed by the Histiocyte society. Recently, Fardet et al. has proposed a Scoring system, "HScore" for diagnosis of reactive HLH. To test the performance of "HScore" in diagnosis of reactive HLH and compare the credibility of the same with the existing gold standard 2004 guidelines in a cohort of Indian patients. This was a descriptive study of cases referred to the department of Pathology for bone marrow examination with suspicion or diagnosis of HLH from Jan 2015 to June 2017. The clinical records of these patients were analysed and diagnosed as positive and negative for HLH using the HLH 2004 guidelines and HScore, the scoring system developed by Fardet et al. Fifty cases fulfilled the inclusion criteria. The variables fever, hepato and /or splenomegaly, high triglyceride levels and marrow hemophagocytosis are highly significant to predict an individuals risk of HLH. We propose a cut-off of ≥ 166 for the diagnosis of HLH by using HScore. If 4 of the 7 criteria are fulfilled by HLH 2004 guidelines, there is an 80% probability of having HLH by HScore. The HScore is less restrictive in confirming a diagnosis of HLH compared to the HLH 2004 guidelines. HScore is a simple, and cost effective tool for diagnosis of reactive HLH. The higher the HScore, more is the probability of HLH.

Hemophagocytic Lymphohistiocytosis in a PICU of a Developing Economy: Clinical Profile, Intensive Care Needs, Outcome, and Predictors of Mortality

OBJECTIVES

To describe the clinical profile, intensive care needs, outcome, and predictors of mortality in critically ill children with hemophagocytic lymphohistiocytosis.

DESIGN

Retrospective case series.

SETTING

PICU of a tertiary care teaching hospital in North India.

PATIENTS

Children 2 months to 12 years old with the diagnosis of hemophagocytic lymphohistiocytosis admitted to PICU from January 2012 to April 2019 (7¼ yr).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Sixty-two children with hemophagocytic lymphohistiocytosis (60 secondary and two primary) were enrolled. The median (interquartile range) age of the study group was 82 months (50.5-124 mo). The median (interquartile range) Pediatric Risk of Mortality III score was 16 (10-23). Majority of hemophagocytic lymphohistiocytosis was infection-associated (n = 51; 82.3%). Among these, scrub typhus accounted for 29% of cases (n = 18), dengue 17.7% (n = 11), bacterial sepsis 14.5% (n = 9), enteric fever 6.5% (n = 4), and other infections 14.5% (n = 9). Systemic-onset juvenile idiopathic arthritis accounted for 9.7% of cases (n = 6) and malignancy for 4.8% patients (n = 3). Majority of cases were treated with steroids (77.4%) and IV immunoglobulin (25.8%). Various complications noted were shock (71%), acute kidney injury (66.1%), acute respiratory distress syndrome (41.9%), disseminated intravascular coagulation (54.8%), CNS dysfunction (54.8%), multiple organ dysfunction syndrome (82.3%), and healthcare-associated infections (14.5%). Intensive care needs for primary illness and/or hemophagocytic lymphohistiocytosis included mechanical ventilation (74.2%); packed RBC (72.3%), fresh frozen plasma (40.3%), and platelet (48.4%) transfusion; vasoactive drugs (71%); and renal replacement therapy (24.2%). The median duration of PICU stay was 5 days (2.5-9.5 d) and mortality was 59.7% (n = 37). On univariate analysis, nonsurvivors had higher Pediatric Risk of Mortality III score; higher proportion of shock, acute kidney injury, acute respiratory distress syndrome, disseminated intravascular coagulation, and multiple organ dysfunction syndrome; the need for blood and blood components, mechanical ventilation, vasoactive drugs, and renal replacement therapy; higher Vasoactive-Inotropic Score; and prolonged duration of mechanical ventilation compared with survivors.

CONCLUSIONS

Hemophagocytic lymphohistiocytosis in PICU is commonly secondary to tropical infections and associated with high mortality. Higher severity of illness; shock and multiple organ dysfunction syndrome; need for blood and blood products, mechanical ventilation, vasoactive drugs, and renal replacement therapy; higher Vasoactive-Inotropic Score; and prolonged mechanical ventilation predicted death. Treatment of underlying infection and a less intense immunosuppressive therapy (steroids ± IV immunoglobulin) are suggested options. A high index of suspicion for complicating hemophagocytic lymphohistiocytosis is required in children with prolonged fever, cytopenias, organomegaly, and organ dysfunction not responding to conventional treatment.

A retrospective analysis of etiology and outcomes of hemophagocytic lymphohistiocytosis in children and adults

Background

Hemophagocytic lymphohistiocytosis (HLH) is a rare but severe, life-threatening inflammatory condition if untreated. We aimed to investigate the etiologies, outcomes, and risk factors for death in children and adults with HLH.

Methods

The medical records of patients who met the HLH criteria of two regional university hospitals in Korea between January 2001 and December 2019 were retrospectively investigated.

Results

Sixty patients with HLH (35 children and 25 adults) were included. The median age at diagnosis was 7.0 years (range, 0.1–83 years), and the median follow-up duration was 8.5 months (range, 0–204 months). Four patients had primary HLH, 48 patients had secondary HLH (20 infection-associated, 18 neoplasm-associated, and 10 autoimmune-associated HLH), and eight patients had HLH of unknown cause. Infection was the most common cause in children (14/35, 40.0%), whereas neoplasia was the most common cause in adults (13/25, 52.0%). Twenty-eight patients were treated with HLH-2004/94 immunochemotherapy. The 5-year overall survival (OS) rate for all HLH patients was 59.9%. The 5-year OS rates for patients with primary, infection-associated, neoplasm-associated, autoimmune-associated, and unknown cause HLH were 25.0%, 85.0%, 26.7%, 87.5%, and 62.5%, respectively. Using multivariate analysis, neoplasm-induced HLH (p=0.001) and a platelet count <50×10⁹/L (p=0.008) were identified as independent risk factors for poor prognosis in patients with HLH.

Conclusion

Infection was the most common cause of HLH in children, while it was neoplasia in adults. The 5-year OS rate for all HLH patients was 59.9%. HLH caused by an underlying neoplasm or a low platelet count at the time of diagnosis were risk factors for poor prognosis.

Hemophagocytic lymphohistiocytosis secondary to visceral leishmaniasis in an endemic area in the north of Minas Gerais, Brazil

INTRODUCTION

Visceral leishmaniasis (VL) is an ill-studied disease that is endemic to several regions of Brazil. It is often complicated by hemophagocytic lymphohistiocytosis (HLH), a potentially fatal disorder resulting from excessive non-malignant activation/proliferation of T lymphocytes and macrophages. Considering the overlapping clinical and laboratory characteristics of these diseases, diagnosing HLH is a challenge. Therefore, tracking the association between VL and HLH is necessary in endemic areas. Although HLH can be inapparent and resolve with antileishmanicides, this may not always occur. HLH causes high lethality; therefore, immunosuppressive therapy should be instituted immediately in order to avoid a fatal outcome.

METHODS:

We described the epidemiological, clinical, laboratory, and therapeutic profile of this association in a region of Brazil endemic for VL.

RESULTS

We presented 39 patients with this association in a retrospective cohort of 258 children who were admitted from January 2012 to June 2017. Of the 39 patients, 31 were from urban areas (79.5%), and 21 (53%) were males. The mean age and weight were 2.86 (2.08) years and 14.03 (5.96) kg, respectively. The main symptoms were fever (100%), hepatosplenomegaly (100%), pallor of the skin and mucosa (82.5%), edema (38.5%), bleeding (25%), and jaundice (7.5%). Hemophagocytosis was identified in 16/37 (43.24%) patients, and direct examination revealed that 26/37 (70.27%) patients were positive for VL. The patients were treated as recommended by the Ministry of Health.

CONCLUSIONS

It was observed that HLH is a common complication in endemic areas, and its diagnosis must consider the overlapping of clinical characteristics and pancytopenia.

Familial hemophagocytic lymphohistiocytosis in a girl with a novel homozygous mutation of STX11: A case report

RATIONALE

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare fatal autosomal recessively inherited disease and can be divided into five types. The mortality of untreated patients is up to 95% and it can be healed only after immunochemotherapy for disease control and hematopoietic stem cell transplantation. Clinical data of a girl with late-onset and recurrent hemophagocytic lymphohistiocytosis (HLH) was retrospectively analyzed to determine the etiology and potential pathogenic gene.

PATIENT CONCERNS AND CLINICAL FINDINGS

The proband was a female child patient from a consanguineous marriage family who was 11 years old, and clinically manifested delayed (onset at the age of 4 years and 6 months) and recrudescent HLH. Both of her elder brothers died at the ages of 4 and 5 years, respectively. The patient had a degranulation function defect of CD107a in natural killer (NK) cells, and the degranulation function of cytotoxic T lymphocytes (CTL) obviously declined (ΔMFI: 1.4%, normal ≧2.8%); the degranulation function of NK cells and CTL of her father was also obviously reduced. To identify possible underlying genetic causes, gene mutation analysis was undertaken. A novel homozygous nonsense mutation in STX11 (c.49C>T, p.Q17X) was documented, arising from both her parents.

DIAGNOSIS

According to the clinical manifestations and detection results of STX11, the diagnosis of FHL-type 4 was confirmed and her parents were heterozygotic carriers.

INTERVENTIONS AND OUTCOMES

Good responses to HLH-2004 chemotherapy had been achieved for each onset, and the maximum remission duration (without taking any drug) was 23 months. The patient has been alive for 82 months since the onset, and has stopped taking dexamethasone and etoposide, but is still on oral cyclosporine to maintain the treatment. She has performed HLA matching and now is actively looking for a donor to prepare hematopoietic stem cell transplantation.

CONCLUSIONS

Relevant gene detections should be implemented at the earliest for young patients from consanguineous marriages and with a family history of HLH so as to provide a basis for etiological diagnosis and radical treatment by hematopoietic stem cell transplantation and provide accurate genetic counseling for family members.

Clinical characteristics of extranodal NK/T-cell lymphoma-associated hemophagocytic lymphohistiocytosis

Background

Extranodal natural killer (NK) / T cell lymphoma is a subtype of non-Hodgkin's lymphoma (NHL) that usually has an aggressive clinical course. It is the predominant trigger of lymphoma-associated hemophagocytic syndrome (LAHS), which is highly lethal and with extremely poor prognosis. This study is aiming to characterize the associated clinical features and prognostic factors of the disease.

Patients and methods

Twenty-eight patients with extranodal NK/T cell lymphoma associated hemophagocytic lymphohistiocytosis (HLH) were retrospectively analyzed. The clinical records were collected, and the associations between clinical or laboratory parameters and overall survival (OS) were assessed.

Results

The most frequently clinical characteristics were fever (96.4%), and splenomegaly (81.5%). Concerning the laboratory findings, the most common features were hyperferritinemia (91.7%), grade III/IV thrombocytopenia (64.3%), hypertriglyceridemia (48%), severe anemia (46.4%), hypofibrinogenemia (45%), and grade III/IV neutropenia (32.1%). The interval between the diagnosis of NK/T LAHS and death / last contact was between 4 to 701 days with the median interval of 15 days. We found that higher serum lactic dehydrogenase (LDH) at HLH, hypofibrinogenemia, and splenomegaly were significantly associated with worse survival (P=0.002, 0.003, 0.003). Furthermore, Eastern Cooperative Oncology Group (ECOG) score, extra-upper aerodigestive tract NK/T cell lymphoma (EUNKTL) and cutaneous involvement were risk factors of HLH.

Conclusion

Our data indicated that levels of LDH, fibrinogen, and presence of splenomegaly were prognostic factors of the disease. Higher ECOG scores, EUNKTL and cutaneous involvement were risk factors of NK/T LAHS. Additional independent, prospective clinical trials will be needed to explore optimal treatment.

Are the 2016 EULAR/ACR/PRINTO classification criteria for macrophage activation syndrome applicable to patients with adult-onset Still's disease?

The objectives of this study are to determine whether the 2016 European League Against Rheumatism/American College of Rheumatology/Paediatric Rheumatology International Trials Organization classification criteria for macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (SJIA) can be used to identify MAS in patients with adult-onset Still's disease (AOSD). Using laboratory data from 76 AOSD patients with and without MAS, we analyzed the ability of the collective and individual constitutive elements of the 2016 MAS in SJIA criteria and additional laboratory measures to discriminate between AOSD patients with (n = 16) and without (n = 60) MAS. Cutoff values to determine the sensitivity, specificity, and predictive values were calculated from receiver operating characteristic curves, and modified classification criteria for MAS in AOSD were evaluated. The 2016 MAS in SJIA classification criteria had an overall sensitivity of 100%, specificity of 70.0%, positive predictive value of 47.1%, and negative predictive value of 100% to discriminate between AOSD patients with and without MAS based on laboratory data. Among the individual criteria, the sensitivity of triglycerides (46.7%) and the specificity of ferritin (15.0%) for MAS in AOSD were particularly low. The sensitivity and specificity for classifying MAS in AOSD patients were increased to 100 and 93%, respectively, by excluding triglycerides and changing the cutoff values for other criteria in the 2016 MAS in SJIA classification. The 2016 classification criteria for MAS in SJIA had higher sensitivity but lower specificity to identify MAS in AOSD patients compared with SJIA patients.

Perforin gene variation influences survival in childhood acute lymphoblastic leukemia

Although a growing body of data links mutations in the perforin gene with increased susceptibility to hematologic malignancies, no studies discuss their influence on the clinical course of such diseases. The present study examines the impact of perforin gene variation on the clinical outcome in acute lymphoblastic leukemia (ALL) patients. The study enrolled 312 children aged 1-18 years, treated for ALL. PRF1 gene variants were analyzed through direct DNA sequencing. Variation in rs885822 was found to be associated with overall survival: patients carrying the GG genotype demonstrated a significantly increased risk of death compared to those carrying the A allele, independently of ALL risk groups (HR 3.13, 95%CI 1.16-7.8, p = 0.014). The effect was even more pronounced in high-risk ALL patients (p = 0.006). On the other hand, the presence of the rs35947132 minor A allele was slightly protective with regard to overall prognosis (p = 0.047). No differences in relapse-free survival were observed with regard to genotypes. The results of the study may imply that perforin gene variation has a role in modifying mortality in childhood ALL.

Hemophagocytic lymphohistiocytosis complicated by multiorgan failure: A case report

RATIONALE

We present a case of hemophagocytic lymphohistiocytosis (HLH) with severe pulmonary complication and acute respiratory distress syndrome (ARDS) hospitalized in our intensive care unit (ICU) in 2014; distinctive trait of this case has been the challenging diagnosis, with a bone marrow biopsy always negative, the severe pulmonary complication with ARDS and severe pulmonary hypertension, and the ferritin temporal kinetics that precisely followed the clinical course of disease.

PATIENT CONCERNS

A 32-year-old woman from the Philippines first diagnosed with upper airway infection, was subsequently hospitalized in infectious disease department and treated for community acquired pneumonia.

DIAGNOSES

After clinical picture worsened with a profound respiratory insufficiency, the patient was intubated and transferred to our ICU. During this hospitalization, the clinical picture of fever, cutaneous rashes, lymphadenitis, hepatitis, leukopenia, anemia, hyperferritinemia, hypertriglyceridemia, high level of auto-antibodies, and low NK activity suggested an hemophagocytic lymphohistiocytosis syndrome, even if bone marrow biopsy was negative for hemophagocytosis.

INTERVENTIONS

Immunosuppressive therapy with dexamethasone and etoposide was started, and the patient was discharged from ICU 4 months after admission.

LESSONS

HLH is a rare disorder of the mononuclear phagocytic system, characterized by systemic proliferation of non- neoplastic histiocytes. The diagnosis is often challenging and not all of the diagnostic criteria may be present at the same time; this case shows how complex the diagnosis could be, how hematic ferritin levels could help in following the course of the disease, and the possibility of severe pulmonary complication either due to the disease itself and to possible sovra infections.

Hemophagocytic syndrome in pregnancy: case report, diagnosis, treatment, and prognosis

Diagnosis of hemophagocytic syndrome remains a challenge in particular during pregnancy. Concomitant presence of clinical and biological signs, for example, fever, pancytopenia, hyperferritinemia, and hypertriglyceridemia, should alert clinicians to suspect HPS and proceed to prompt treatments.

Critically Ill Children With Hemophagocytic Lymphohistiocytosis: A Case Series of 14 Patients

Children with hemophagocytic lymphohistiocytosis (HLH) are at an increased risk of critical illness. In this study, we described the clinical characteristics of critically ill children with HLH and identify factors associated with poor clinical outcomes. Children who were diagnosed with HLH with emergent admission to Children's Intensive Care Unit (CICU) between January 1, 2000 and October 31, 2015 were included. The primary outcome was CICU mortality. Over the 15-year period, there were 14 critically ill patients with HLH with 23 CICU admissions. Median age at HLH diagnosis was 8.2 years (interquartile range [IQR], 2.9 to 11.3). Overall CICU mortality was 8 of 23 CICU admissions (34.8%). Factors that were associated with CICU mortality in critically ill children with HLH identified in this study include: a worse median pediatric index of mortality 2 score (4.7% in survivors [IQR, 2.9% to 11.6%] vs. 2.4% [IQR, 1.2% to 4.3%]; P=0.031); higher median peak serum lactate level (mmol/L) within 24 hours of admission (5.6 [IQR, 2.7 to 17.4] vs. 1.6 [IQR, 1.2 to 2.8]; P=0.032); the need for mechanical ventilation (100% vs. 46.7%; P=0.019); inotropic support (87.5% vs. 20.0%; P=0.006); renal replacement therapy (50% vs. 0%; P=0.008); and blood product transfusion episodes (24.5 [IQR, 14.3 to 46.8] vs. 3.0 [IQR, 1.0 to 9.0]; P=0.002). Further studies are required to validate the factors that are associated with poor outcomes in critically ill children with HLH.

A consensus review on malignancy-associated hemophagocytic lymphohistiocytosis in adults

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of severe immune activation and dysregulation resulting in extreme and often life-threatening inflammation. HLH has been well recognized in pediatric populations, and most current diagnostic and therapeutic guidelines are based on pediatric HLH. Recently there has been recognition of HLH in adults, especially secondary to immune deregulation by an underlying rheumatologic, infectious, or malignant condition. This review is focused on malignancy-associated HLH (M-HLH), in which possible mechanisms of pathogenesis include severe inflammation, persistent antigen stimulation by the tumor cells, and loss of immune homeostasis because of chemotherapy, hematopoietic stem cell transplantation, or infection. Previously considered rare, M-HLH may occur in up to 1% of patients with hematologic malignancies. M-HLH is often missed or diagnosed late in most published studies, and it has been associated with a poor median survival of less than 2 months. Identification of the clinical and laboratory features specific to M-HLH in adults may allow early detection, consultation with HLH experts, and intervention. Improved management of adult M-HLH with optimal combinations of T-lympholytic and immunosuppressive agents and the incorporation of novel agents based on the pediatric experience hopefully will improve outcomes in adults with M-HLH. Cancer 2017;123:3229-40. © 2017 American Cancer Society.

Impairment of Immune Function in Children with Familial Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a severe systemic syndrome associated with hyperactivation of macrophages and impaired regulation of the immune system. Two forms of HLH are currently recognized: genetically determined or familial (FHLH), and secondarily developed in the course of primary diseases, like autoimmune disorders, rheumatoid disorders, cancers, or infections. In the Polish population, FHLH is rather rare. The aim of the present study was to assess the immune function in a group of children with clinical symptoms suggesting FHLH. Forty five children with suspected HLH of the median age of 4 years and 15 healthy children, taken as a control group, were enrolled into the study. All presented results were obtained with the use of flow cytometry. In the HLH group, there were only three cases identified with the UNC13D gene mutation responsible for the FHLH3 phenotype. Another four children, without known mutation, were classified as FHLH because of frequent recurrence of the disease. In all cases of FHLH, cell cytotoxicity was impaired compared with healthy children (p = 0.003). Perforin expression in FHLH was normal or higher than that observed in controls (p = 0.09). In case of patients with mutation in the Munc13 protein, degranulation was lower than that in healthy children (<5 %). The findings of this study demonstrate that children with known mutations responsible for the FHLH development are immunocompromised. However, it requires further elucidation whether the presence of currently unknown mutations could lead to a similar phenotype.

Recent advances in diagnostic and therapeutic guidelines for primary and secondary hemophagocytic lymphohistiocytosis

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome characterized by excessive activation of macrophages and T cells resulting from defective cytotoxicity. It is potentially life threatening due to the large amounts of cytokines released by the activated macrophages and lymphocytes secondary to a hyperinflammatory response. It has a high fatality in children with an incidence of approximately 1.2cases/million per year.

METHOD

The literature was extensively searched in PubMed, MEDLINE and Google scholar.

RESULTS

A variable and nonspecific symptomatology can delay the diagnosis and hence requires a high index of suspicion in both primary and secondary HLH.

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis: response to HLH-04 treatment protocol

INTRODUCTION

Hemophagocytic syndrome, macrophage activation syndrome, reactive histiocytosis or hemophagocytic lymphohistiocytosis (HLH) represent a group of diseases whose common thread is reactive or neoplastic mononuclear phagocytic system cells and dendritic cell proliferation.

CLINICAL CASE

We present a case of an HLH probably associated with Epstein-Barr virus (EBV) in a 4-year-old male patient treated with HLH-04 protocol. Viral etiology in HLH is well accepted. In this case, clinical picture of HLH was assumed secondary to EBV infection because IgM serology at the time of clinical presentation was the only positive factor in the viral panel.

CONCLUSIONS

Diagnosis of HLH is the critical first step to successful treatment. The earlier it is identified, the less the tissue damage and reduced risk of multiple organ failure, which favors treatment response.

Clonal CD8+ T Lymphocytic Proliferation and Karyotypical Abnormalities in an EBV Associated Hemophagocytic Lymphohistiocytosis

EBV associated hemophagocytic lymphohistiocytosis and EBV-positive T cell lymphoproliferative disease of childhood share many histologic and clinical features, which sometimes makes it very difficult to render a definitive diagnosis. In this report, we present a 16-year-old male who developed symptoms clinically consistent with EBV associated hematophagocytic lymphohistiocytosis including fulfilling most of HLH diagnostic criteria and responding promptly to HLH targeted therapy. However, histologic and cytogenetics features of this case are very concerning for EBV-positive T cell lymphoproliferative disease of childhood. This case demonstrates an ambiguous boundary of these two disease entities and emphasizes the importance of comprehensive evaluation and clinical correlation with cases suspicious of EBV driven hemophagocytic or lymphoproliferative process.

Hemophagocytic Lymphohistiocytosis and Gastrointestinal Bleeding: What a Surgeon Should Know

This paper presents to the surgical community an unusual and often ignored cause of gastrointestinal bleeding. Hemophagocytic syndrome or hemophagocytic lymphohistiocytosis (HLH) is a rare medical entity characterized by phagocytosis of red blood cells, leucocytes, platelets, and their precursors in the bone marrow by activated macrophages. When intestinal bleeding is present, the management is very challenging with extremely high mortality rates. Early diagnosis and treatment seem to be the most important factors for a successful outcome. We present two cases and review another 18 from the literature.

Hemophagocytic Lymphohistiocytosis Associated with Visceral Leishmaniasis: Varied Presentation

Visceral leishmaniasis (VL) is endemic in many parts of India. Rarely, it may be complicated by hemophagocytic lymphohistiocytosis (HLH) that has varied presentation and course. We describe two cases of VL complicated by HLH that were markedly different in clinical presentation, course and management. First case presented with Fever of unknown origin whereas second case had fever with severe bleeding manifestations. VL was diagnosed by bone marrow aspiration and serum rk39 immunodiagnostic test respectively in these cases. HLH was diagnosed by HLH 2004 diagnostic criteria. VL was treated by intravenous amphotericin B in both cases. HLH was managed by treating primary disease in the first case whereas steroid was given for management in the second case. High index of suspicion is crucial for early diagnosis of HLH to reduce morbidity and mortality.

Hemophagocytic lymphohistiocytosis: review of etiologies and management

Hemophagocytic lymphohistiocytosis (HLH) covers a wide array of related life-threatening conditions featuring ineffective immunity characterized by an uncontrolled hyperinflammatory response. HLH is often triggered by infection. Familial forms result from genetic defects in natural killer cells and cytotoxic T-cells, typically affecting perforin and intracellular vesicles. HLH is likely under-recognized, which contributes to its high morbidity and mortality. Early recognition is crucial for any reasonable attempt at curative therapy to be made. Current treatment regimens include immunosuppression, immune modulation, chemotherapy, and biological response modification, followed by hematopoietic stem-cell transplant (bone marrow transplant). A number of recent studies have contributed to the understanding of HLH pathophysiology, leading to alternate treatment options; however, much work remains to raise awareness and improve the high morbidity and mortality of these complex conditions.

Hemophagocytic syndrome in children and adults

Hemophagocytic syndrome, also known as hemophagocytic lymphohistiocytosis (HLH), is a heterogenic syndrome, which leads to an acute, life-threatening inflammatory reaction. HLH occurs both in children and adults, and can be triggered by various inherited as well as acquired factors. Depending on the etiology, HLH can be divided into genetic (i.e., primary) and acquired (i.e., secondary) forms. Among genetic HLH forms, one can distinguish between familial HLH and other genetically conditioned forms of HLH. Acquired HLH can be typically triggered by infections, autoimmune diseases, and malignancies. The most common symptoms of HLH are unremitting fever, splenomegaly, and peripheral blood cytopenia. Some severely ill patients present with central nervous system involvement. Laboratory tests reveal hyperferritinemia (often >10,000 μg/L), increased serum concentration of soluble receptor α for interleukin-2 (>2,400 U/L), hypertriglyceridemia, hypofibrinogenemia, coagulopathy, hyponatremia, hypoproteinemia, and elevated liver transaminases and bilirubin. Prognosis in HLH is very serious. Genetic HLH is always lethal if adequate therapy is not administered. Similarly, severe acquired cases often lead to death without appropriate treatment. Since HLH can be encountered by various specialists in the medical field, basic knowledge of this entity such as diagnostic criteria and treatment should be familiar to all physicians.

Systemerkrankungen

Systemerkrankungen als Ursache einer Lebererkrankung sind häufig, ohne dass man genaue Zahlen angeben kann. Die verschiedenen Grunderkrankungen sind für sich betrachtet zwar selten, nur dadurch, dass viele Erkrankungen in Betracht gezogen werden müssen, ergibt sich eine relative Häufung. Durch Fortschritte auf dem Gebiet der molekularbiologischen Diagnostik insbesondere bei den Stoffwechselerkrankungen lassen sich heute bereits viele der in Frage kommenden Grunderkrankungen eindeutig nachweisen. Allerdings ist bei keiner der Erkrankungen ein hundertprozentiger molekularbiologischer Nachweis möglich. Damit ergibt sich eine sichere Diagnose nur bei einem positiven Nachweis. Bei fehlendem Nachweis einer bisher bekannten für die Erkrankung spezifischen Mutation bleibt die Zuordnung entweder enzymatischen Tests oder klinischer Diagnose vorbehalten. Insbesondere bei der Manifestation als akutes Leberversagen ist die für die Diagnosesicherung erforderliche Zeit damit oft nicht vorhanden.

Infection Associated with Hemophagocytic Lymphohisticytosis triggered by nosocomial Infection

Hemophagocytic lymphohistiocytosis (HLH) can occur as primary idiopathic syndrome or secondary to neoplastic, infection or autoimmune processes. It is characterized by the proliferation of histiocytes with phagocytosis of formed elements of blood. Clinical manifestations include signs and symptoms of immune activation and pancytopenia. This report presents a child with infection associated with HLH trigged by Acinetobacter baumannii sepsis. Multidrug-resistant Acinetobacter, an emergent nosocomial pathogen but so far in the literature, it has not been reported to cause HLH.

Presentation of hemophagocytic lymphohistiocytosis due to a novel MUNC 13-4 mutation masked by partial therapeutic immunosuppression

Hemophagocytic lymphohistiocytosis is a potentially fatal disease characterized by excessive macrophage and lymphocyte activity. Patients can be affected following immune activation after an oncologic, autoimmune or infectious trigger. An associated gene mutation may be found which impairs cytolytic lymphocyte function. We describe a pediatric case of hemophagocytic lymphohistiocytosis with a novel mutation of MUNC 13-4 whose diagnosis was confounded by concurrent immunosuppression. Clinical reassessment for hemophagocytic lymphohistiocytosis is necessary in persistently febrile patients with laboratory derangements in the setting of immunosuppressive agent exposure.