Primary and secondary hemophagocytic lymphohistiocytosis: clinical features, pathogenesis and therapy

Single center clinical analysis of macrophage activation syndrome complicating juvenile rheumatic diseases

BACKGROUND

Macrophage activation syndrome (MAS), an example of secondary hemophagocytic lymphohistiocytosis, is a potentially fatal complication of rheumatic diseases. We aimed to study the clinical and laboratory characteristics, treatment schemes, and outcomes of different rheumatic disorders associated with MAS in children. Early warning indicators of MAS have also been investigated to enable clinicians to make a prompt and accurate diagnosis.

METHODS

Fifty-five patients with rheumatic diseases complicated by MAS were enrolled between January 2017 and December 2022. Clinical and laboratory data were collected before disease onset, at diagnosis, and after treatment with MAS, and data were compared between patients with systemic juvenile idiopathic arthritis (sJIA), Kawasaki disease (KD), and systemic lupus erythematosus (SLE). A random forest model was established to show the importance score of each variable with a significant difference.

RESULTS

Most (81.8%) instances of MAS occurred during the initial diagnosis of the underlying disease. Compared to the active stage of sJIA, the platelet count, erythrocyte sedimentation rate, and fibrinogen level in sJIA-MAS were significantly decreased, whereas ferritin, ferritin/erythrocyte sedimentation rate, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and D-dimer levels were significantly increased. Ferritin level, ferritin/erythrocyte sedimentation rate, and platelet count had the greatest predictive value for sJIA-MAS. The level of IL-18 in the sJIA-MAS group was significantly higher than in the active sJIA group, whereas IL-6 levels were significantly lower. Most patients with MAS were treated with methylprednisolone pulse combined with cyclosporine, and no deaths occurred.

CONCLUSIONS

Thrombocytopenia, ferritin levels, the ferritin/erythrocyte sedimentation rate, and elevated aspartate aminotransferase levels can predict the occurrence of MAS in patients with sJIA. Additionally, our analysis indicates that IL-18 plays an important role in the pathogenesis of MAS in sJIA-MAS.

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.

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.

Hemophagocytic lymphohistiocytosis as a rare complication of dengue haemorrhagic fever: a case report

BACKGROUND

Haemophagocytic lymphohistiocytosis (HLH) is an uncommon systemic inflammatory syndrome that can happen secondary to numerous conditions. It rarely occurs due to dengue infection causing significant mortality and morbidity even with appropriate treatment. The outcome is further poor if the diagnosis of HLH is delayed or left untreated. Therefore, a high degree of clinical suspicion is paramount in diagnosing HLH.

CASE PRESENTATION

A 17-year-old Sinhalese boy was admitted to a tertiary care hospital in Sri Lanka with a 4-day history of fever, headache, nausea, vomiting, and diarrhea. He was hemodynamically stable, and the serological investigation confirmed a dengue infection. On the fifth day of fever, he entered the critical phase of dengue infection, confirmed by ultrasound evidence of plasma leaking. However, he had ongoing high fever spikes during the critical phase, and even after the critical phase was over, the fever spikes continued. Simultaneously, hepatosplenomegaly was noticed, and he showed persistent thrombocytopenia, neutropenia, and anemia despite the resolution of the critical phase. Further, the workup revealed a serum ferritin level of > 3000 ng/mL triglyceride level of 314 mg/dL, and the bone marrow biopsy revealed an increased haemophagocytic activity. Secondary HLH was diagnosed on the basis of criteria used in the HLH-2004 trial and successfully managed with intravenous dexamethasone 10 mg/body surface area/day for the first 2 weeks, followed by a tapering regimen over 8 weeks.

CONCLUSION

This case emphasizes the need to consider HLH as a potential complication when persistent fever and cytopenias are present after recovering from dengue fever, particularly in patients with unusual clinical features like hepatosplenomegaly. Early recognition and prompt treatment with appropriate immunosuppressive therapy, such as intravenous dexamethasone, can lead to a successful response and good prognosis.

Hemophagocytic Lymphohistiocytosis in a Patient with Hodgkin Lymphoma, HIV, and Epstein-Barr Virus

Hemophagocytic lymphohistiocytosis (HLH) is an aggressive and life-threatening syndrome of excessive immune activation. It occurs in many underlying conditions and all age groups due to severe and uncontrolled inflammatory reactions, with the resultant overproduction of immune cells and cytokines. This leads to multi-organ damage (if not detected early and treated properly) with a mortality of more than 55%. We present a case of a 38-year-old male patient who presented with HLH with concurrent HIV/AIDS, and Epstein-Barr virus (EBV)-related Hodgkin lymphoma. We aim to emphasize the importance of considering HLH and cancer in patients with HIV/AIDS.

Pediatric Hemophagocytic Lymphohistiocytosis: Formation of an Interdisciplinary HLH Working Group at a Single Institution

Fever of unknown origin is a common presentation in children with an extensive differential diagnosis that encompasses multiple specialties. From a hematologic standpoint, the differential includes hyperinflammatory syndrome, such as hemophagocytic lymphohistiocytosis (HLH), among others. Due to the rarity of HLH and nonspecific symptoms at initial presentation, specialists are often consulted later in the disease progression, which complicates disease evaluation further. Cook Children's Medical Center (CCMC) has recently developed a multidisciplinary histiocytic disorder group that is often consulted on cases presenting with fever of unknown origin to increase awareness and potentially not miss new HLH cases. In this study, we examine the clinical presentation and workup of 13 patients consulted by the HLH work group at a single institution and describe the clinical course of 2 patients diagnosed with HLH. The goal of this project was to describe the formation of a disease-specific team and the development of a stepwise diagnostic approach to HLH. A review of the current diagnostic criteria for HLH may be warranted given findings of markers such as soluble IL2 receptor and ferritin as nonspecific and spanning multiple disciplines including rheumatology, infectious disease, and hematology/oncology.

Misdiagnosis of adult primary hemophagocytic lymphohistiocytosis as NK/T-cell lymphoma: A case report

We reported a case of a 19-year-old male patient with central nervous system symptoms as the main clinical manifestations, and multiple intracranial and abdominal occupying lesions visualized by imaging examinations, who was initially misdiagnosed as NK/T-cell lymphoma but poorly responsive to the treatment. Finally, he was diagnosed as familial hemophagocytic lymphohistiocytosis type-2 by genome sequencing, perforin test and pedigree study. The patient survived well after allogeneic hematopoietic stem cell transplantation. Central nervous system symptoms could be the main clinical manifestations in patients with primary hemophagocytic lymphohistiocytosis , whose early-stage manifestations of blood system were usually atypical, easily leading to misdiagnosis. In clinical practice, primary hemophagocytic lymphohistiocytosis should be considered in patients with central nervous system symptoms and unknown causes. The combination of rapid immunological function test and genome sequencing contributes to the diagnosis of primary hemophagocytic lymphohistiocytosis.

A Case of Secondary Hemophagocytic Lymphohistiocytosis Presenting with Severe Dyserythropoeisis in a Patient with Autoimmune Hemolysis

The diagnosis of hemophagocytic lymphohistiocytosis (HLH) requires that several clinical criteria are met, and often relies on the identification of rare hemophagocytic cells in the bone marrow. Given the challenge in making the diagnosis, additional signs of immune dysregulation in the bone marrow would have practical clinical use in cases where overt hemophagocytosis is not seen. We present here a case of secondary HLH in a patient with autoimmune hemolysis ultimately diagnosed as Evans syndrome that initially presented with profound dyserythropoeisis in both the peripheral blood and bone marrow. We also explore an association between dyserythropoeisis and HLH in a series of cases previously seen at our institution.

The Role of GM-CSF Autoantibodies in Infection and Autoimmune Pulmonary Alveolar Proteinosis: A Concise Review

Autoantibodies to multiple cytokines have been identified and some, including antibodies against granulocyte-macrophage colony-stimulating factor (GM-CSF), have been associated with increased susceptibility to infection. High levels of GM-CSF autoantibodies that neutralize signaling cause autoimmune pulmonary alveolar proteinosis (aPAP), an ultrarare autoimmune disease characterized by accumulation of excess surfactant in the alveoli, leading to pulmonary insufficiency. Defective GM-CSF signaling leads to functional deficits in multiple cell types, including macrophages and neutrophils, with impaired phagocytosis and host immune responses against pulmonary and systemic infections. In this article, we review the role of GM-CSF in aPAP pathogenesis and pulmonary homeostasis along with the increased incidence of infections (particularly opportunistic infections). Therefore, recombinant human GM-CSF products may have potential for treatment of aPAP and possibly other infectious and pulmonary diseases due to its pleotropic immunomodulatory actions.

Tuberculosis endotypes to guide stratified host-directed therapy

There is hope that host-directed therapy (HDT) for Tuberculosis (TB) can either shorten treatment duration, help cure drug resistant disease or limit the immunopathology. Many candidate HDT drugs have been proposed, however solid evidence only exists for a few select patient groups. The clinical presentation of TB is variable, with differences in severity, tissue pathology, and bacillary burden. TB clinical phenotypes likely determine the potential benefit of HDT. Underlying TB clinical phenotypes, there are TB "endotypes," defined as distinct molecular profiles, with specific metabolic, epigenetic, transcriptional, and immune phenotypes. TB endotypes can be characterized by either immunodeficiency or pathologic excessive inflammation. Additional factors, like comorbidities (HIV, diabetes, helminth infection), structural lung disease or Mycobacterial virulence also drive TB endotypes. Precise disease phenotyping, combined with in-depth immunologic and molecular profiling and multimodal omics integration, can identify TB endotypes, guide endotype-specific HDT, and improve TB outcomes, similar to advances in cancer medicine.

Development of a dendrimer PAMAM‑based gold biochip for rapid and sensitive detection of endogenous IFN‑γ and anti‑IFN‑γ IgG in patients with hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a rare but severe disease characterized by immune hyperactivation and cytokine storm. Given the high mortality rate of HLH, there is a need for more effective diagnostic tools and treatments. The present study developed a dendrimer‑based protein biochip for rapid, sensitive and simultaneous detection of serum interferon (IFN)‑γ and endogenous anti‑IFN‑γ antibody (Ab) in patients with HLH. A gold biochip was modified with 1, 4‑phenylene diisothiocyanate (PDITC), polyamidoamine (PAMAM) or PDITC‑activated PAMAM. The optimal immobilization concentration for Ab capture and the reaction concentration for detecting Ab on the PDITC‑activated PAMAM‑modified biochip were 6.25 and 3.12 µg/ml, respectively; the limit of detection of IFN‑γ protein was 50 pg/ml. The efficiency of the protein‑probed biochip in detecting IFN‑γ and anti‑IFN‑γ Ab in serum samples from 77 patients with HLH was evaluated; the positive rates for IFN‑γ and anti‑IFN‑γ IgG Ab were 63.6% (49/77) and 61.0% (47/77), respectively. The present results demonstrated that the PDITC‑activated PAMAM‑modified biochip might be a sensitive tool for the specific detection of IFN‑γ and anti‑IFN‑γ Ab in serum, and might have clinical applicability for the diagnosis of HLH.

SARS-CoV-2 Infection-Associated Hemophagocytic Lymphohistiocytosis

OBJECTIVES

A subset of coronavirus disease 2019 (COVID-19) patients exhibit clinical features of cytokine storm. However, clinicopathologic features diagnostic of hemophagocytic lymphohistiocytosis (HLH) have not been reported. We studied the reticuloendothelial organs of 4 consecutive patients who died of COVID-19 and correlated with clinical and laboratory parameters to detect HLH.

METHODS

Autopsies were performed on 4 patients who died of COVID-19. Routine H&E staining and immunohistochemical staining for CD163 were performed to detect hemophagocytosis. Clinical and laboratory results from premortem blood samples were used to calculate H-scores.

RESULTS

All 4 cases demonstrated diffuse alveolar damage within the lungs. Three of the 4 cases had histologic evidence of hemophagocytosis within pulmonary lymph nodes. One case showed hemophagocytosis in the spleen but none showed hemophagocytosis in liver or bone marrow. Lymphophagocytosis was the predominant form of hemophagocytosis observed. One patient showed diagnostic features of HLH with an H-score of 217, while a second patient likely had HLH with a partial H-score of 145 due to a missing triglyceride level. The remaining 2 patients had H-scores of 131 and 96.

CONCLUSIONS

This is the first report of severe acute respiratory syndrome coronavirus 2-associated HLH. Identification of HLH in a subset of patients with severe COVID-19 will inform clinical trials of therapeutic strategies.

GM-CSF-based treatments in COVID-19: reconciling opposing therapeutic approaches

Therapeutics against coronavirus disease 2019 (COVID-19) are urgently needed. Granulocyte–macrophage colony-stimulating factor (GM-CSF), a myelopoietic growth factor and pro-inflammatory cytokine, plays a critical role in alveolar macrophage homeostasis, lung inflammation and immunological disease. Both administration and inhibition of GM-CSF are currently being therapeutically tested in COVID-19 clinical trials. This Perspective discusses the pleiotropic biology of GM-CSF and the scientific merits behind these contrasting approaches.

Recombinant granulocyte–macrophage colony-stimulating factor (GM-CSF) as well as antibodies targeted at GM-CSF or its receptor are being tested in clinical trials for coronavirus disease 2019 (COVID-19). This Perspective introduces the pleiotropic functions of GM-CSF and explores the rationale behind these different approaches.

The Role of Cytokines including Interleukin-6 in COVID-19 induced Pneumonia and Macrophage Activation Syndrome-Like Disease

Severe COVID-19 associated pneumonia patients may exhibit features of systemic hyper-inflammation designated under the umbrella term of macrophage activation syndrome (MAS) or cytokine storm, also known as secondary haemophagocytic lymphohistocytosis (sHLH). This is distinct from HLH associated with immunodeficiency states termed primary HLH -with radically different therapy strategies in both situations. COVID-19 infection with MAS typically occurs in subjects with adult respiratory distress syndrome (ARDS) and historically, non-survival in ARDS was linked to sustained IL-6 and IL-1 elevation. We provide a model for the classification of MAS to stratify the MAS-like presentation in COVID-19 pneumonia and explore the complexities of discerning ARDS from MAS. We discuss the potential impact of timing of anti-cytokine therapy on viral clearance and the impact of such therapy on intra-pulmonary macrophage activation and emergent pulmonary vascular disease.

Hemophagocytic Lymphohistiocytosis Complicating Methotrexate Toxicity

Hemophagocytic syndrome or hemophagocytic lymphohistiocytosis (HLH) is a rare but potentially fatal disease caused by dysregulated activation of macrophages against one's blood cells. Major pathologic feature of HLH is hemophagocytosis. We present a case of HLH complicating methotrexate toxicity in a 65-year-old psoriatic patient with history of renal disease. Diagnosis of HLH was established as he fulfilled five out of eight HLH diagnostic criteria. This case report is presented to enlighten clinicians about the clinical entity of HLH and to suspect and recognize this rare and generally fatal disease at the earliest.

Clinical and laboratory features, treatment, and outcomes of macrophage activation syndrome in 80 children: a multi-center study in China

BACKGROUND

Macrophage activation syndrome (MAS) is a major cause of morbidity and mortality in pediatric rheumatology. We aimed to further understand the clinical features, treatment, and outcome of MAS in China.

METHODS

A multi-center cohort study was performed in seven hospitals in China from 2012 to 2018. Eighty patients with MAS were enrolled, including 53 cases with systemic juvenile idiopathic arthritis (SJIA-MAS), 10 cases of Kawasaki disease (KD-MAS), and 17 cases of connective tissue disease (CTD-MAS). The clinical and laboratory data were collected before (pre-), at onset, and during full-blown stages of MAS. We compared the data among the SJIA-MAS, KD-MAS, and CTD-MAS subjects.

RESULTS

51.2% of patients developed MAS when the underlying disease was first diagnosed. In patients with SJIA, 22.6% (12/53) were found to have hypotension before the onset of SJIA-MAS. These patients were also found to have significantly increased aspartate aminotransferase (AST) and lactate dehydrogenase (LDH), as well as decreased albumin (P < 0.05), but no difference in alanine aminotransferase, ferritin, and ratio of ferritin/erythrocyte sedimentation rate (ESR) at onset of MAS when compared to pre-MAS stages of the disease. In addition, ferritin and ratio of ferritin/ESR were significantly elevated in patients at full-blown stages of SJIA-MAS compared to pre-MAS stage. Significantly increased ferritin and ratio of ferritin/ESR were also observed in patients with SJIA compared to in KD and CTD. Receiver-operating characteristic analysis showed that 12,217.5 μg/L of ferritin and 267.5 of ferritin/ESR ratio had sensitivity (80.0% and 90.5%) and specificity (88.2% and 86.7%), respectively, for predicting full-blown SJIA-MAS. The majority of the patients received corticosteroids (79/80), while biologic agents were used in 12.5% (10/80) of cases. Tocilizumab was the most commonly selected biologic agent. The overall mortality rate was 7.5%.

CONCLUSIONS

About half of MAS occurred when the underlying autoimmune diseases (SJIA, KD, and CTD) were first diagnosed. Hypotension could be an important manifestation before MAS diagnosis. Decreased albumin and increased AST, LDH, ferritin, and ratio of ferritin/ESR could predict the onset or full blown of MAS in patient with SJIA.

Hemophagocytic lymphohistiocytosis complicating invasive pneumococcal disease: a pediatric case report

Background

Hemophagocytic lymphohistiocytosis (HLH) is an infrequent but life-threatening disease due to excessive immune activation. Secondary HLH can be triggered by infections, autoimmune diseases, and malignant diseases. Streptococcus pneumoniae is a pathogenic bacterium responsible for invasive pneumococcal disease (IPD) such as meningitis and bacteremia. Although the pneumococcal conjugate vaccine (PCV) has led to reductions in IPD incidence, cases of IPD caused by serotypes not included in PCV are increasing. There are few reports of secondary HLH caused by IPD in previously healthy children. We herein report a rare case of a previously healthy boy with secondary HLH complicating IPD of serotype 23A, which is not included in the pneumococcal 13-valent conjugate vaccine (PCV-13).

Case presentation

An 11-month-old boy who had received three doses of PCV-13 was hospitalized with prolonged fever, bilateral otitis media, neutropenia and elevated C-reactive protein (CRP) levels. Blood culture on admission revealed S. pneumoniae, leading to a diagnosis of IPD. HLH was diagnosed based on a prolonged fever, neutropenia, anemia, hepatosplenomegaly, hemophagocytosis in the bone marrow, and elevated serum levels of triglycerides, ferritin, and soluble interleukin-2 receptor. He received broad-spectrum antibiotics and intravenous immunoglobulins for IPD and high-dose steroid pulse therapy and cyclosporine A for HLH; thereafter, his fever resolved, and laboratory findings improved. The serotype of the isolated S. pneumoniae was 23A, which is not included in PCV-13.

Conclusions

It is important to consider secondary HLH as a complication of IPD cases with febrile cytopenia or hepatosplenomegaly, and appropriate treatment for HLH should be started without delay.

Comparison between clinical features and prognosis of malignancy- and non-malignancy-associated pediatric hemophagocytic lymphohistiocytosis

BACKGROUND

The differences between the clinical characteristics and survival time in malignancy- and non-malignancy-associated secondary hemophagocytic lymphohistiocytosis (HLH) are unclear. Here, we describe the clinical characteristics, prognostic factors, and survival outcomes of malignancy-associated HLH compared to that of non-malignancy-associated HLH.

METHODS

We retrospectively analyzed 91 pediatric patients with HLH (age < 14 years) at the Affiliated Hospital of Qingdao University Pediatric Department between January 2005 and October 2016. The patients were divided into the malignancy-associated group (n = 22) and non-malignancy-associated group (n = 69, also considered the control group). The clinical features were compared using the Mann-Whitney U and χ² tests. The overall survival time was compared using log rank and Mann-Whitney U tests.

RESULTS

Hemoglobin (HGB; p = 0.004), alanine aminotransferase (ALT; p = 0.002), and aspartate aminotransferase (AST; p = 0.001) levels in the malignancy-associated group differed from that in the non-malignancy-associated group. The mean survival times were 26.9 ± 3.82 months (malignancy-associated HLH) and 35.03 ± 2.19 months (non-malignancy-associated HLH). The overall survival time between the two groups was not statistically significantly different (p = 0.055). Univariate analysis showed that disseminated intravascular coagulation (DIC) score > 5 (p = 0.001), albumin < 25 g/L (p = 0.000), HGB < 60 g/L (p = 0.001), and platelet count (PLT) < 30 × 10⁹/L (p = 0.042) correlated with prognosis. Multivariate Cox analysis showed that albumin < 25 g/L (p = 0.017), HGB < 60 g/L (p = 0.027), and bone marrow hemophagocytosis (p = 0.034) correlated with worse prognosis.

CONCLUSIONS

Patients with non-malignancy-associated HLH do not have better survival, although their prognosis is relatively better in clinical practice. A higher DIC score at diagnosis and lower albumin, HGB, and PLT levels are negative prognostic factors in malignancy-associated HLH.

Laboratory Assays of Immune Cell Function in Immunodeficiencies

Laboratory assays of immune cell function are essential for understanding the type and function of immune defects. These assessments should be performed in conjunction with a detailed history and physical examination, which should guide the evaluation of patients with a suspected immune deficiency. Laboratory assays of immune cell function are critical for assessing and demonstrating the functional impact of genetic mutations. Advances in diagnostic techniques continue to expand the ability of clinicians and researchers to understand the complex immune pathophysiology that underlies these disorders.

Successful Modified Therapy in a Patient with Probable Infection-Associated Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a rare, hyperinflammatory syndrome characterized by clinical signs and symptoms of extreme inflammation. In adults, HLH is typically a complication of infections, autoimmune diseases, and malignancies. While the disease is often fatal, classic management of HLH revolves around early diagnosis and initiation of protocolized therapy. We present a case of a previously healthy 56-year-old female who developed distributive shock requiring intubation, vasopressors, and continuous venovenous hemofiltration. In the setting of multiple infectious syndromes, severe cytopenias, and rising direct hyperbilirubinemia, her diagnosis of HLH was confirmed. Therapy was initiated with dexamethasone and two doses of reduced-intensity etoposide based on the patient's clinical course. Over the next few weeks, she continued to improve on dexamethasone monotherapy and has maintained remission up to the present with complete resolution of her cytopenias and return of baseline renal function. Our case highlights the variability in the management of probable infection-associated HLH (IHLH) with a good patient outcome. We demonstrate the potential to treat IHLH with partial protocols and minimal chemotherapeutics.

Natural Killer Cell Degranulation Defect: A Cause for Impaired NK-Cell Cytotoxicity and Hyperinflammation in Fanconi Anemia Patients

Fanconi anemia (FA) is a rare inherited syndrome characterized by progressive bone marrow failure (BMF), abnormal skin pigmentation, short stature, and increased cancer risk. BMF in FA is multifactorial and largely results from the death of hematopoietic stem cells due to genomic instability. Also, inflammatory pathology in FA has been previously reported, however the mechanism is still not clear. In literature, decreased NK-cell count and/or impaired NK-cell activity, along with other immunological abnormalities have been described in FA-patients (1). However, to the best of our knowledge, this is the first report showing a defective degranulation mechanism leading to abnormal NK-cell cytotoxicity in FA-patients, which may explain the development of a hyperinflammatory response in these patients. This may predispose some patients to develop Hemophagocytic lymphohistiocytosis (HLH) which manifests with prolonged fever, progressive cytopenias and organomegaly. Early diagnosis and initiation of immunosuppressive therapy in these patients will help to better manage these patients. We also propose FA genes to be listed as a cause of familial HLH.

Central Nervous System Involvement in 179 Chinese Children with Hemophagocytic Lymphohistiocytosis

Background:

Central nervous system (CNS) involvement is found in many patients with hemophagocytic lymphohistiocytosis (HLH). In this study, we mainly analyzed neurological symptoms, imaging findings, cerebrospinal fluid (CSF), and their relationship with outcomes of HLH children.

Methods:

Related data of 179 Chinese pediatric patients with HLH admitted to our center from January 2010 to December 2015 were analyzed retrospectively. Diagnosis and treatment were based on the HLH-2004 protocol. Two-tailed Chi-squared test was used to compare between different groups, and Kaplan-Meier survival curves were used to analyze the overall survival (OS) of patients with HLH.

Results:

In the present study, 21.2% (38/179) of total patients had neurological symptoms including seizure, irritability, somnolence, and unconsciousness. There were 80 (50.0%, excluding 19 patients without imaging data) patients with cranial imaging abnormalities. There were 14.7% (17/116, excluding 63 patients who did not accept lumbar puncture) of patients with abnormal CSF results. CNS involvement is defined as abnormalities in one or more of CNS symptoms, radiological findings, and CSF. Thus, 60.3% of them had CNS involvement. As for the prognosis, the median follow-up time was 3.2 years (17 lost to follow-up). The probable 3-year OS of children was higher without CNS involvement (86.0% ± 4.6%) than those with CNS involvement (68.9% ± 4.9%, hazard ratio [HR] = 2.286, P = 0.019). Among them, the probable 3-year OS of children without CNS symptoms was 76.0% ± 3.8%, higher than with CNS symptoms (59.5% ± 8.1%, HR = 2.147, P = 0.047). The 3-year OS of children with abnormal CSF was 64.7% ± 11.6%, compared with normal CSF (85.1% ± 3.7%, HR = 0.255, P = 0.038).

Conclusions:

HLH patients with CNS involvement might have worse outcomes compared with those without CNS involvement, and CNS symptoms and CSF changes are more important to access the prognosis than imaging abnormality.

Hemophagocytic lymphohistiocytosis associated to Haemophilus parainfluenzae endocarditis- a case report

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare but severe and potentially fatal syndrome that is characterized by increased proliferation and activation of benign macrophages with hemophagocytosis throughout the reticuloendothelial system. This syndrome is classified as primary (genetic) or secondary when acquired in the context of infections (usually viral), malignancies, rheumatologic and metabolic diseases.

CASE SUMMARY

We report a case of HLH complicating a Haemophilus parainfluenzae mitral valve endocarditis and resolving under antibiotic and surgical treatment alone. We also review other case reports of infective endocarditis associated with HLH.

CONCLUSION

The syndrome is probably underdiagnosed. To our knowledge, this is the first report of a HLH syndrome associated with H. parainfluenzae endocarditis.

The influence of various therapeutic regimens on early clinical and laboratory response and outcome of children with secondary hemophagocytic lymphohistiocytosis

INTRODUCTION

Secondary hemophagocytic lymphohistiocytosis (sHLH) is a life-threatening syndrome of severe hyperinflammation which is often triggered by infection or autoimmune disease (macrophage activation syndrome - MAS). The aim of our study was to assess the frequency of sHLH/MAS in children treated in our institution and to compare the effectiveness of various therapeutic interventions.

MATERIAL AND METHODS

Between 2005 and 2013, 24 children (age: 1-17 years) were consecutively treated for sHLH/MAS. Therapy was based on glucocorticoids (GCs) in high or standard doses (hd-GCs or sd-GCs), intravenous immunoglobulin (IVIG), and cyclosporin A (CyA). A comparison of selected laboratory and clinical parameters during the first 72 h of treatment and after a week from the last intervention applied in the first 72 h after diagnosis was performed retrospectively.

RESULTS

The majority of patients (14/24, 58%) suffered from sHLH/MAS in the course of an autoimmune disease (12 patients diagnosed with a systemic form of juvenile idiopathic arthritis). We found with a confidence level of 95% that the application of hd-GCs in the first 24 h caused rapid alleviation of fever, reduction of hepatosplenomegaly, and an increase in thrombocytes and s-fibrinogen concentrations. The use of combination therapy with hd-GCs, IVIG, and CyA in the first 72 h caused a faster increase in s-fibrinogen. All patients survived and were alive at the follow-up of 1-8 years.

CONCLUSIONS

The results indicate that treatment of sHLH/MAS based on hd-GCs, CyA and IVIG is an effective therapy in children.

A nine-month-old-boy with Atypical Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammation caused by uncontrolled proliferation of activated lymphocytes and histiocytes. Often, HLH is an acquired syndrome. We report a case of a nine month-old-boy presented with hepatosplenomegaly, severe anemia, thrombocytopenia, hypertriglyceridemia and high hyperferritinemia. These clinical features of HLH prompted a wide range of infectious and auto-immune tests to be performed. After an extensive diagnostic workup, he was referred to the immune-hematologic unit for HLH suspicion with an unknown cause. Primary HLH due to familial lymphohistiocytosis (FLH) was first evoked in front of consanguinity, probable HLH in the family, early onset, and in the absence of a causative pathology like infection or cancer. However, functional tests were normal. Atypical features like the: absence of fever, hypotonia, recurrent diarrhea since diversification, hematuria, and proteinuria suggested an inborn metabolism error with gastrointestinal involvement. Specific tests were performed to reach a final diagnosis.

Lemierre's Syndrome as a Trigger for Secondary Hemophagocytic Lymphohistiocytosis

Secondary hemophagocytic lymphohistiocytosis (sHLH) is a rare hyperinflammatory disorder caused by an aberrant immune response to a number of infectious or inflammatory conditions. Successful treatment of this potentially fatal condition requires early recognition and prompt therapy directed at the underlying trigger. In this report, we describe the clinical presentation, diagnostic findings, management, and outcome of a child with Lemierre's syndrome-associated sHLH. This is the first reported association of these 2 rare conditions and expands the number of known triggers for sHLH.

An Unusual Triad of Hemophagocytic Syndrome, Lymphoma and Tuberculosis in a Non-HIV Patient

BACKGROUND Lymphoma complicated with hemophagocytic syndrome and tuberculosis has been rarely reported. The clinical and radiological presentation of these potentially fatal conditions can be easily confused and there is a potential for misdiagnosis. CASE REPORT We present a 58-year-old Hispanic female who was admitted to the hospital with dizziness and fever. Her initial admission diagnosis was severe sepsis secondary to community acquired pneumonia. She was started on intravenous antibiotics. Due to mediastinal lymphadenopathy, lymphoma was considered as a differential diagnosis for which she underwent bronchoscopy and endobronchial ultrasound-guided sampling of her mediastinal lymph nodes. Lymph node aspirate was suggestive of lymphoma. Initial cultures were negative. Her clinical course was complicated with respiratory failure, cytopenia, and rapidly progressive cervical lymphadenopathy. The patient underwent cervical lymph node excision and bone marrow biopsy. The pathology of the lymph nodes confirmed T cell lymphoma, and bone marrow revealed hemophagocytosis. The patient was started on chemotherapy but she continued to deteriorate and died on day 20 of her hospital admission. Post-mortem results of cultures from a cervical lymph node biopsy and PCR were positive for Mycobacterium tuberculosis. CONCLUSIONS We suggest an aggressive tissue diagnosis with staining for acid-fast bacilli for early diagnosis in patients presenting with hemophagocytic syndrome secondary to lymphoma as coexisting tuberculosis is a consideration. Tuberculosis re-activation should be considered in patients from an endemic region who present with lymphoma and a deteriorating clinical condition.

Macrophage activation syndrome in systemic lupus erythematosus: a multicenter, case-control study in China

The objective of this study was to describe the clinical and laboratory characteristics, precipitating factors, treatment, and outcome of macrophage activation syndrome (MAS) complicating systemic lupus erythematosus (SLE). A multicenter case-control study was performed across six tertiary hospitals from 1997 to 2014. A total of 32 patients with SLE-associated MAS were enrolled. Sixty-four age- and sex-matched SLE patients diagnosed in the same period without MAS episodes were selected as controls. The most frequent clinical feature was fever, followed by splenomegaly. Hyperferritinemia, hypoalbuminemia, and hyper-lactate dehydrogenase (LDH)-nemia were among the most common laboratory abnormalities. Compared with pre-MAS visit, patients at the onset of MAS had greater frequencies of renal involvement, liver dysfunction, and cytopenia. Receiver operating characteristic (ROC) analysis identified optimal cutoff values of ferritin (>662.5 ng/mL) and LDH (>359 U/mL) to predict the occurrence of MAS in SLE. SLE flare and infection were the common triggers of MAS in SLE. Abortion and parturition were recorded as well. The overall mortality rate was 12.5%. All patients received corticosteroids. Cyclosporine A, cyclophosphamide, and etoposide were the three most commonly used immunosuppressants. Rituximab was given to one patient. Intravenous immunoglobulin (IVIG) was added for 46.9% patients. MAS is a potentially fatal complication of SLE. Its occurrence is most frequently associated with active SLE disease or infection. The presentation of unexplained fever, cytopenia, or liver dysfunction, with high levels of ferritin and LDH, in patients with SLE should raise the suspicion of MAS. Corticosteroids with immunosuppressants and IVIG may be an appropriate treatment.

Perforin and CD107a testing is superior to NK cell function testing for screening patients for genetic HLH

Primary hemophagocytic lymphohistiocytosis (HLH) can be caused by biallelic mutations in PRF1, encoding perforin, or UNC13D, STXBP2, STX11, RAB27A, LYST, and AP3B1, encoding proteins involved in cytotoxic lymphocyte degranulation. Natural killer (NK)-cell cytotoxicity assays can quickly screen for all of these genetic diseases, facilitating treatment, but combining NK-cell perforin expression and CD107a upregulation tests can as well. To determine the relative diagnostic accuracies for each approach, we retrospectively reviewed screening test performance in 1614 patients referred for HLH evaluation. For each test, we generated a receiver operating characteristic (ROC) curve, and calculated area under the curve (AUC) and diagnostic parameters at optimal threshold. We generated an AUC for combining perforin and CD107a tests by creating a logistic regression model and applying model-generated coefficients to patient values. Sensitivities of NK-cell function, perforin mean channel fluorescence (MCF), and CD107a MCF to detect biallelic mutations were 59.5%, 96.6%, and 93.8%, with specificities of 72.0%, 99.5%, and 73%. AUCs for NK-cell cytotoxicity, perforin MCF, CD107a MCF, and combined perforin and CD107a MCFs were 0.690, 0.971, 0.860, and 0.838. Perforin and CD107a tests are more sensitive and no less specific compared with NK cytotoxicity testing for screening for genetic HLH and should be considered for addition to current HLH criteria.

Macrophage Activation Syndrome: different mechanisms leading to a one clinical syndrome

BACKGROUND

Macrophage activation syndrome (MAS) is a severe complication of rheumatic disease in childhood, particularly in systemic Juvenile Idiopathic Arthritis (sJIA). It is characterize by an uncontrolled activation and proliferation of T lymphocytes and macrophages.

MAIN CONTENT

MAS is currently classified among the secondary or acquired forms of haemophagocytic lymphohistiocytosis (sHLH). The reason is that MAS shares clinical and laboratory features with primary genetic HLH (pHLH). In this context is conceivable that some of the pathogenic mechanisms of pHLH may be involved in other forms of HLH. Heterozygosity for mutations of genes involved in pHLH may lead to a cytotoxic defect and to a development of clinical overt disease. But other different contributors might be involved to the development of MAS such as infections or underlying inflammation. In MAS, the inflammatory status of the patient is a major contributor of the disease. Indeed, the majority of the MAS episodes occurs during active disease phases or at disease onset. In addition, recent evidence in animals and humans suggest that genetics may also play a major role in contributing to hyperinflammation and particularly to macrophages hyper-responses.

CONCLUSIONS

We hypothesize that HLH may be one unique clinical syndrome, to whose generation different mechanisms may contribute, and maintained by one final effector mechanism.

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.

High-Volume Hemofiltration in Critically Ill Patients With Secondary Hemophagocytic Lymphohistiocytosis/Macrophage Activation Syndrome: A Prospective Study in the PICU

OBJECTIVES

Hemophagocytic lymphohistiocytosis, which includes primary (familial) and secondary hemophagocytic lymphohistiocytosis, is a fatal disease in children. Macrophage activation syndrome was defined in patients who met secondary hemophagocytic lymphohistiocytosis criteria with an underlying autoimmune disease. High-volume hemofiltration has shown beneficial effects in severe sepsis and multiple organ dysfunction syndrome. Secondary hemophagocytic lymphohistiocytosis/macrophage activation syndrome shares many pathophysiologic similarities with sepsis. The present study assessed the effects of high-volume hemofiltration in children with secondary hemophagocytic lymphohistiocytosis/macrophage activation syndrome.

DESIGN

A single-center nonrandomized concurrent control trial.

SETTING

The PICU of Shanghai Children's Hospital, Shanghai Jiao Tong University.

PATIENTS

Thirty-three critically ill secondary hemophagocytic lymphohistiocytosis/macrophage activation syndrome patients treated between January 2010 and December 2014.

INTERVENTIONS

Thirty-three patients were divided into two groups: high-volume hemofiltration + hemophagocytic lymphohistiocytosis-2004 group (17 cases) or hemophagocytic lymphohistiocytosis-2004 group (16 cases). High-volume hemofiltration was defined as an ultrafiltrate flow rate of 50-70 mL/kg/hr. Clinical and biological variables were assessed before initiation and after 48 and 72 hours of high-volume hemofiltration therapy.

MEASUREMENTS AND MAIN RESULTS

The total mortality rate was 42.4% (14/33), but mortality at 28 days was not significantly different between the two groups (high-volume hemofiltration + hemophagocytic lymphohistiocytosis-2004 group: five deaths, 29.4%; hemophagocytic lymphohistiocytosis-2004 group: nine deaths, 56.3%; chi-square, 2.431; p = 0.119). Children received high-volume hemofiltration for 60.2 ± 42.0 hours. After 48 and 72 hours respectively, a significant decrease in serum ferritin (p < 0.001), aspartate aminotransferase (p = 0.037 and p < 0.001), total bilirubin (p = 0.041 and p = 0.037), and serum creatinine (p = 0.006 and p = 0.004) levels were observed. Furthermore, the natural killer-cell activity up-regulated (p = 0.047) after 72 hours. Furthermore, significantly decreased levels of serum tumor necrosis factor-α (from 91.5 ± 44.7 ng/L at 48 hr to 36.7 ± 24.9 ng/L at 72 hr; p = 0.007)) and interleukin-6 (from 46.9 ± 21.1 ng/L at 48 hr to 27.7 ± 14.5 ng/L at 72 hr; p < 0.0001) were observed. After 7 days, patients receiving high-volume hemofiltration had significantly lower bilirubin, creatinine, ferritin, procalcitonin, lactate dehydrogenase level, tumor necrosis factor-α, and interleukin-6 levels, and needed less mechanical ventilation compared with hemophagocytic lymphohistiocytosis-2004 group patients. No serious adverse events were observed.

CONCLUSIONS

High-volume hemofiltration may improve organ function by decreasing cytokine levels (tumor necrosis factor-α and interleukin-6). High-volume hemofiltration may be an effective adjunctive treatment in secondary hemophagocytic lymphohistiocytosis/macrophage activation syndrome.

Malignancy-associated hemophagocytic lymphohistiocytosis in adults: Relation to hemophagocytosis, characteristics, and outcomes

BACKGROUND

Malignancy-associated hemophagocytic lymphohistiocytosis (HLH) in adults is a highly lethal disorder. Knowledge gaps have resulted in under diagnosis or delayed diagnosis.

METHODS

The University of Texas MD Anderson Cancer Center pathology database (1991-2014) was retrospectively interrogated for the keywords "hemophagocytosis" and/or "lymphohistiocytosis." Seventy-seven adult patients were identified. All had an underlying malignancy. Sixteen patients who had insufficient documentation were excluded.

RESULTS

The majority of patients who had pathologic evidence of hemophagocytosis/lymphohistiocytosis had an incomplete workup to confirm or refute HLH using the 2004 HLH criteria (HLH-2004; n = 8 variables), which is a common problem in adult HLH. Only 13 of 61 patients (21%) met the HLH-2004 diagnostic criteria based on available retrospective data. To identify potentially missed cases of HLH, the published literature was reviewed, and selected additional variables known to be associated with adult HLH were selected, resulting in extended diagnostic criteria of 18 variables. Thirty-five patients met the extended criteria, and 33 had follow-up data available. The median overall survival of the 13 patients who met both the extended criteria and the HLH-2004 criteria was similar to that of the 20 patients who met the extended criteria but NOT the HLH-2004 criteria (1.43 vs 1.76 months, respectively; P = .34) indicating a similar underlying, aggressive, systemic process. Twenty-six patients did not meet either criteria, and 17 had follow-up data available. The median overall survival of the 17 patients who had pathologic hemophagocytosis or lymphohistiocytosis but met neither criteria was significantly superior to the survival of those who met both the extended criteria and the HLH-2004 criteria and those who met the extended criteria but not the HLH-2004 criteria (17.27 vs 1.43 vs 1.76, respectively; P = .002).

CONCLUSIONS

The addition of diagnostic laboratory variables that are more easily and rapidly available in smaller institutions and primary care settings than the HLH-2004 variables may be a good surrogate to raise early suspicion of malignancy-associated HLH. Prospective validation is warranted. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2857-2866. © 2016 American Cancer Society.

Current Updates on Classification, Diagnosis and Treatment of Hemophagocytic Lymphohistiocytosis (HLH)

Hemophagocytic lymphohistiocytosis (HLH) is a life threatening hyperinflammatory syndrome characterized by excessive activation of macrophages and T cells resulting from defective cytotoxicity. Severe hyperinflammation caused by uncontrolled proliferation of activated lymphocytes and histiocytes (macrophages) secreting high amounts of inflammatory cytokines threatens the life of the patient and may lead to death unless arrested by appropriate treatment. HLH can be caused either by certain underlying genetic diseases (familial HLH), or may also occur due to particular triggers in patients with no known inherited disorder (acquired HLH). Due to life threatening nature of the disease, early diagnosis and initiation of immunosuppressive therapy is extremely important. HLH diagnosis is based on constellation of clinical manifestations and laboratory parameters which often overlap with those of severe infection or sepsis. Identification of patients with familial HLH and their underlying genetic defects requires specialized laboratory tests and is important for predicting relapses and planning early therapeutic hematopoietic stem cell transplantation (HSCT). A high suspicion and thorough clinical, immunological and genetic work-up is required for diagnosis of HLH. Prompt initiation of adequate treatment is essential for the survival. Substantial progress has been made in exploring the complex cause and pathophysiology of HLH and also in management of HLH patients.

Central nervous system vasculitis in adults and children

Primary angiitis of the central nervous system (PACNS) is an inflammatory brain disease targeting the cerebral blood vessels, leading to a wide spectrum of signs and symptoms, including neurologic deficits, cognitive dysfunction, and psychiatric symptoms. The inflammation could be reversible if diagnosed and treated early. The diagnosis requires the careful consideration and rapid evaluation of systemic underlying conditions and disease mimics. The differential diagnosis is distinctly different for angiography-positive and -negative PACNS subtypes and differs depending on age, so there is childhood PACNS or adult PACNS. Distinct disease subtypes have been described, with characteristic disease course, neuroimaging findings, and histopathologic features. Novel and traditional biomarkers, including von Willebrand factor antigen and cytokine levels, can help diagnose, and define subtype and disease activity. Treatment of PACNS should be tailored to the disease subtypes and clinical symptoms. Beyond immunosuppression it should include medications to control symptoms in order to support and enhance the child's or adult's ability to actively participate in rehabilitation. The mortality of PACNS has decreased; studies determining the morbidity and its determinants are urgently needed.

Hemophagocytic lymphohistiocytosis: An unusual complication in disseminated Mycobacterium tuberculosis

Background:

Hemophagocytic lymphohistiocytosis (HLH) is an uncommon, potentially fatal, hyperinflammatory syndrome that may rarely complicate the clinical course of disseminated Mycobacterium tuberculosis (MTB). The clinical course of tuberculosis-associated HLH (TB-HLH) has been reported to be unpredictable.

Materials and Methods:

Here we describe the clinicopathological features, laboratory parameters, management, and outcome data of a patient who satisfied the 2004 diagnostic criteria for HLH secondary to disseminated MTB; we also do a systematic review of the international literature on TB-HLH. The literature review (January 1975–March 2014) found that HLH complicated the clinical course of 63 tuberculosis patients (41 males, 22 females, mean age = 45 ± 23.5 years) with a high mortality rate of 49% (31/63 died). The mean serum ferritin level (n = 44/63) was 5963 ng/mL (range 500–38,539 ng/mL); and a higher proportion (54.2%) of patients had pancytopenia at presentation. On univariate analysis (n = 53/63), age >30 years [hazard ratio (HR): 2.79, 95% confidence interval (CI):1.03–7.56, P = 0.03], presence of comorbidities (HR 4.59, CI: 1.08–19.52, P = 0.04), marked hemophagocytosis in bone marrow (HR: 2.65, CI: 1.16–6.05, P = 0.02), and nonusage/delayed usage of antitubercular therapy (ATT) (HR: 3.44, CI: 1.51–7.87, P = 0.003) were associated with decreased survival, though none of these parameters attained statistical significance (P > 0.05) in multivariate analysis. Usage of corticosteroids and/or immunomodulator drugs (HR 1.00, CI: 0.66–3.22, P = 0.35) did not alter the outcome in these patients.

Conclusion:

HLH should be considered as a differential diagnosis in patients with tuberculosis who present with cytopenias, organomegaly, and coagulopathy. Strong clinical suspicion and early usage of ATT might be useful in reducing the morbidity and mortality. The utility of immunosuppressive/immunomodulator therapy lacks general concensus among treating physicians, and warrants further studies.

Screening assays for primary haemophagocytic lymphohistiocytosis in children presenting with suspected macrophage activation syndrome

BACKGROUND

Primary haemophagocytic lymphohistiocytosis (HLH) screening assays are increasingly being performed in patients presenting with macrophage activation syndrome (MAS). The objective of this study was to describe their diagnostic and prognostic relevance in children who had presented to paediatric rheumatology and had undergone investigative work up for MAS.

METHODS

Data was obtained retrospectively from an existing protein screening assay database and patient records. Assays included: intracellular expression of perforin in CD56+ Natural Killer (NK) cells; CD107a Granule Release Assay (GRA) in response to PHA in NK cells, or anti-CD3 stimulation of CD8 lymphocytes; in males Signal Lymphocyte Activating Molecule Associated Protein (SAP), and X-linked Inhibitor of Apoptosis Protein (XIAP) expression. All assays, requested by paediatric rheumatology, of children who had undergone investigative work up for MAS over a 5-year period (2007-2011) were included.

RESULTS

Twenty-one patients (15 female), median age 6.5 years (range 0.6-16) with follow-up of 16 months (range 1-51), were retrospectively identified. At presentation, 3/21 (14 %) fulfilled HLH-2004 diagnostic criteria. At least one screening test result was available for all 21 patients; 7/21 (33 %) had at least one persistent screening test abnormality. Of this group 4/7 (57 %) died or required haematopoietic stem cell transplantation (HSCT), compared to 1/14 (7 %) with no screening test abnormality (p = 0.025). 3/21 (14 %) ultimately had a diagnosis of primary HLH (two confirmed genetically; XIAP, familial HLH type 3, and one confirmed clinically). Of the six patients with abnormal GRA 5/6 had negative routine genetic results.

CONCLUSIONS

Screening for primary HLH is warranted for children whose first rheumatological presentation is with MAS, since overall 14 % had an eventual diagnosis of primary HLH. A persistently abnormal GRA in patients presenting with MAS defines a high-risk group with poor outcome (mortality or HSCT), possibly due to as yet unidentified genetic cause.

Preceding Annular Skin Lesions in a Patient with Hemophagocytic Lymphohistiocytosis

The cutaneous manifestations of hemophagocytic lymphohistiocytosis (HLH) are variable and nonspecific. A 42-year-old man presented with multiple annular, erythematous patches on the trunk for 3 months. Two months later, he presented with bullae along with high fever. The laboratory examination showed pancytopenia, hypertriglyceridemia, and hypofibrinogenemia. The bone marrow biopsy specimen showed an active hemophagocytosis. On the basis of these findings, a diagnosis of HLH was concluded. After five cycles of chemotherapy, his skin lesion completely resolved. Taking the results together, we suggest that annular skin lesion can be added to the list of cutaneous manifestations of HLH.