Macrophage activation syndrome in children with systemic juvenile idiopathic arthritis and systemic lupus erythematosus

The NLRP3 inflammasome is essential for IL-18 production in a murine model of macrophage activation syndrome

Hyperinflammatory disease is associated with an aberrant immune response resulting in cytokine storm. One such instance of hyperinflammatory disease is known as macrophage activation syndrome (MAS). The pathology of MAS can be characterised by significantly elevated serum levels of interleukin-18 (IL-18) and interferon gamma (IFNγ). Given the role for IL-18 in MAS, we sought to establish the role of inflammasomes in the disease process. Using a murine model of CpG-oligonucleotide-induced MAS, we discovered that the expression of the NLRP3 inflammasome was increased and correlated with IL-18 production. Inhibition of the NLRP3 inflammasome or the downstream caspase-1 prevented MAS-mediated upregulation of IL-18 in the plasma but, interestingly, did not alleviate key features of hyperinflammatory disease including hyperferritinaemia and splenomegaly. Furthermore blockade of IL-1 receptor with its antagonist IL-1Ra did not prevent the development of CpG-induced MAS, despite being clinically effective in the treatment of MAS. These data demonstrate that, during the development of MAS, the NLRP3 inflammasome was essential for the elevation in plasma IL-18 - a key cytokine in clinical cases of MAS - but was not a driving factor in the pathogenesis of CpG-induced MAS.

Heterogeneity of macrophage activation syndrome and treatment progression

Macrophage activation syndrome (MAS) is a rare complication of autoimmune inflammatory rheumatic diseases (AIIRD) characterized by a progressive and life-threatening condition with features including cytokine storm and hemophagocytosis. Predisposing factors are typically associated with microbial infections, genetic factors (distinct from typical genetically related hemophagocytic lymphohistiocytosis (HLH)), and inappropriate immune system overactivation. Clinical features include unremitting fever, generalized rash, hepatosplenomegaly, lymphadenopathy, anemia, worsening liver function, and neurological involvement. MAS can occur in various AIIRDs, including but not limited to systemic juvenile idiopathic arthritis (sJIA), adult-onset Still's disease (AOSD), systemic lupus erythematosus (SLE), Kawasaki disease (KD), juvenile dermatomyositis (JDM), rheumatoid arthritis (RA), and Sjögren's syndrome (SS), etc. Although progress has been made in understanding the pathogenesis and treatment of MAS, it is important to recognize the differences between different diseases and the various treatment options available. This article summarizes the cell types and cytokines involved in MAS-related diseases, the heterogeneity, and treatment options, while also comparing it to genetically related HLH.

A MASsive attack: a pediatric case of macrophage activation syndrome complicated by DIC as an onset of systemic juvenile idiopathic arthritis successfully treated with anakinra and review of the literature

Macrophage activation syndrome (MAS) is one of the most severe complications of systemic juvenile idiopathic arthritis (sJIA). Around 10% of patients with sJIA exhibit systemic symptoms accompanied by macrophage activation syndrome (MAS), but it may occur subclinically in another 30-40%. In this article, we present a case of a 3-year-old girl diagnosed with sever MAS as an onset of sJIA complicated by disseminated intravascular coagulation (DIC). First symptoms of sJIA were observed about 5 months before setting the diagnose, and it was resembling urticaria. A comprehensive allergological diagnostics were conducted, but no cause for the skin changes was identified. A few weeks before admission to the hospital, the girl was presented with a high fever. During the hospital stay, viral, bacterial, and fungal infections were ruled out. However, the findings indicated significantly elevated markers of inflammation (ferritin, CRP, ESR) in the conducted tests. Meanwhile, swelling of the feet and ankle joints was also observed. Based on Ravelli criteria, we set the diagnosis of MAS in a course of sJIA. We implemented treatment with steroid pulses, followed by cyclosporine; however, her clinical condition did not improve. Despite intensive treatment, skin petechiae were observed twice, and laboratory tests revealed a very high INR along with an extremely low level of fibrinogen. The patient required multiple plasma transfusions and clotting factor administrations. Due to the severe condition of the girl, we initiated biological treatment with anakinra, after which the child's condition gradually improved. In this case, we want to present how dynamic and life-threatening the course of MAS can be. In the discussion, we are also comparing our approach and the applied treatment with the currently available knowledge.

The NLRP3 inflammasome is essential for IL-18 production in a murine model of macrophage activation syndrome

Hyperinflammatory disease is associated with an aberrant immune response resulting in cytokine storm. One such instance of hyperinflammatory disease is known as macrophage activation syndrome (MAS). The pathology of MAS can be characterised by significantly elevated serum levels of interleukin (IL)-18 and interferon (IFN)-γ. Given the role for IL-18 in MAS, we sought to establish the role of inflammasomes in the disease process. Using a murine model of CpG-DNA induced MAS, we discovered that the expression of the NLRP3 inflammasome was increased and correlated with IL-18 production. Inhibition of the NLRP3 inflammasome, or downstream caspase-1, prevented MAS-mediated upregulation of plasma IL-18 but interestingly did not alleviate key features of hyperinflammatory disease including hyperferritinaemia and splenomegaly. Furthermore IL-1 receptor blockade with IL-1Ra did not prevent the development of CpG-induced MAS, despite being clinically effective in the treatment of MAS. These data demonstrate that in the development of MAS, the NLRP3 inflammasome was essential for the elevation in plasma IL-18, a key cytokine in clinical cases of MAS, but was not a driving factor in the pathogenesis of CpG-induced MAS.

Is it possible to predict a disease course prone to macrophage activation syndrome at systemic juvenile idiopathic arthritis diagnosis?

OBJECTIVES

Macrophage activation syndrome (MAS) is a severe complication of systemic juvenile idiopathic arthritis (SJIA). We aimed to compare the characteristics of SJIA patients who developed MAS in the disease course to those who never experienced MAS.

METHODS

Patients with SJIA were included. The features of the patients at the time of SJIA diagnosis were compared. Multivariate logistic regression and ROC analyses were used while evaluating factors associated with MAS.

RESULTS

Overall, 126 SJIA patients (M/F:1.17) were included. Eighty-six (68.2%) never had MAS. At the time of SJIA diagnosis, age was younger; the duration of fever was longer; rash, hepatomegaly, and splenomegaly were more frequent and arthralgia/arthritis was less common among patients who had MAS in the follow-up than those who never had MAS. Also, white blood cell, neutrophil, and platelet counts and fibrinogen were lower, while transaminases, lactate dehydrogenase, triglyceride (TG), and ferritin levels were higher among patients with MAS than those without MAS. The multivariate regression analysis disclosed age at symptom onset, duration of fever, platelet count, TG and ferritin levels as independent MAS predictors. For ferritin level/platelet count (F/P) ratio at the time of SJIA diagnosis, a threshold of ≥1.1 performed best to predict a MAS-prone disease course with a sensitivity of 90% and a specificity of 82.6%.

CONCLUSION

The F/P ratio at the time of SJIA diagnosis may be a promising biomarker to predict MAS-prone disease course in SJIA. Determining MAS-prone patients at the time of SJIA diagnosis could assist physicians while tailoring SJIA treatment individually. Key points • Systemic juvenile idiopathic arthritis (SJIA) patients with macrophage activation syndrome (MAS) differ from SJIA patients who never have MAS, at the time of SJIA diagnosis. • It could be possible to predict a MAS-prone disease course at the time of SJIA diagnosis. • The ferritin/platelet ratio is a promising biomarker for predicting MAS-prone SJIA disease course.

Recurrent macrophage activation syndrome due to hyperimmunoglobulin D syndrome: a case-based review

Hyperimmunoglobulin D syndrome (HIDS) is a hereditary autoinflammatory disease characterized by recurrent inflammatory attacks with fever, abdominal pain, lymphadenopathy, aphthous stomatitis, and skin lesions. There are few reports on HIDS patients complicated with macrophage activation syndrome (MAS); however, to our knowledge, there is no case of HIDS with recurrent MAS attacks. We report two pediatric patients initially diagnosed as Kawasaki disease and systemic juvenile idiopathic arthritis presented with recurrent MAS episodes with prolonged fever, skin rash, hepatosplenomegaly, cervical lymphadenopathy, aphthous stomatitis, headache, pancytopenia, hyperferritinemia, and hypofibrinogenemia, finally diagnosed as HIDS with a documented homozygous MVK gene mutation. This is the first report on recurrent MAS attacks due to HIDS in pediatric patients who were successful treated with corticosteroids and anti-IL-1 therapies. Thus, clinicians should be vigilantly investigated signs of autoinflammatory diseases in patients with recurrent MAS attacks during their disease course, and HIDS should be considered an underlying disease for triggering recurrent MAS attacks. We have also reviewed the current literature regarding HIDS cases complicated with a MAS attack and summarized their demographic, treatment, and outcome characteristics. Key points • Hyperimmunoglobulin D syndrome should be considered in differential diagnosis in patients who experienced recurrent macrophage activation syndrome attacks.

Lung Involvement in Systemic Juvenile Idiopathic Arthritis: A Narrative Review

Systemic juvenile idiopathic arthritis associated with lung disorders (sJIA-LD) is a subtype of sJIA characterized by the presence of chronic life-threatening pulmonary disorders, such as pulmonary hypertension, interstitial lung disease, pulmonary alveolar proteinosis and/or endogenous lipoid pneumonia, which were exceptionally rare before 2013. Clinically, these children show a striking dissociation between the relatively mild clinical manifestations (tachypnoea, clubbing and chronic cough) and the severity of the pulmonary inflammatory process. Our review describes sJIA-LD as having a reported prevalence of approximately 6.8%, with a mortality rate of between 37% and 68%. It is often associated with an early onset (<2 years of age), macrophage activation syndrome and high interleukin (IL)-18 circulating levels. Other risk factors may be trisomy 21 and a predisposition to adverse reactions to biological drugs. The most popular hypothesis is that the increase in the number of sJIA-LD cases can be attributed to the increased use of IL-1 and IL-6 blockers. Two possible explanations have been proposed, named the “DRESS hypothesis” and the “cytokine plasticity hypothesis”. Lung ultrasounds and the intercellular-adhesion-molecule-5 assay seem to be promising tools for the early diagnosis of sJIA-LD, although high resolution computed tomography remains the gold standard. In this review, we also summarize the treatment options for sJIA-LD, focusing on JAK inhibitors.

Looking into the IL-1 of the storm: are inflammasomes the link between immunothrombosis and hyperinflammation in cytokine storm syndromes?

Inflammasomes and the interleukin (IL)-1 family of cytokines are key mediators of both inflammation and immunothrombosis. Inflammasomes are responsible for the release of the pro-inflammatory cytokines IL-1β and IL-18, as well as releasing tissue factor (TF), a pivotal initiator of the extrinsic coagulation cascade. Uncontrolled production of inflammatory cytokines results in what is known as a "cytokine storm" leading to hyperinflammatory disease. Cytokine storms can complicate a variety of diseases and results in hypercytokinemia, coagulopathies, tissue damage, multiorgan failure, and death. Patients presenting with cytokine storm syndromes have a high mortality rate, driven in part by disseminated intravascular coagulation (DIC). While our knowledge on the factors propagating cytokine storms is increasing, how cytokine storm influences DIC remains unknown, and therefore treatments for diseases, where these aspects are a key feature are limited, with most targeting specific cytokines. Currently, no therapies target the immunothrombosis aspect of hyperinflammatory syndromes. Here we discuss how targeting the inflammasome and pyroptosis may be a novel therapeutic strategy for the treatment of hyperinflammation and its associated pathologies.

2021 American College of Rheumatology Guideline for the Treatment of Juvenile Idiopathic Arthritis: Therapeutic Approaches for Oligoarthritis, Temporomandibular Joint Arthritis, and Systemic Juvenile Idiopathic Arthritis

OBJECTIVE

To provide updated guidelines for pharmacologic management of juvenile idiopathic arthritis (JIA), focusing on treatment of oligoarthritis, temporomandibular joint (TMJ) arthritis, and systemic JIA with and without macrophage activation syndrome. Recommendations regarding tapering and discontinuing treatment in inactive systemic JIA are also provided.

METHODS

We developed clinically relevant Patient/Population, Intervention, Comparison, and Outcomes questions. After conducting a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation approach was used to rate the quality of evidence (high, moderate, low, or very low). A Voting Panel including clinicians and patients/caregivers achieved consensus on the direction (for or against) and strength (strong or conditional) of recommendations.

RESULTS

Similar to those published in 2019, these JIA recommendations are based on clinical phenotypes of JIA, rather than a specific classification schema. This guideline provides recommendations for initial and subsequent treatment of JIA with oligoarthritis, TMJ arthritis, and systemic JIA as well as for tapering and discontinuing treatment in subjects with inactive systemic JIA. Other aspects of disease management, including factors that influence treatment choice and medication tapering, are discussed. Evidence for all recommendations was graded as low or very low in quality. For that reason, more than half of the recommendations are conditional.

CONCLUSION

This clinical practice guideline complements the 2019 American College of Rheumatology JIA and uveitis guidelines, which addressed polyarthritis, sacroiliitis, enthesitis, and uveitis. It serves as a tool to support clinicians, patients, and caregivers in decision-making. The recommendations take into consideration the severity of both articular and nonarticular manifestations as well as patient quality of life. Although evidence is generally low quality and many recommendations are conditional, the inclusion of caregivers and patients in the decision-making process strengthens the relevance and applicability of the guideline. It is important to remember that these are recommendations. Clinical decisions, as always, should be made by the treating clinician and patient/caregiver.

Treatment Strategies for Central Nervous System Effects in Primary and Secondary Haemophagocytic Lymphohistiocytosis in Children

Purpose of Review

This review presents an appraisal of current therapeutic options for the treatment of central nervous system haemophagocytic lymphohistiocytosis (CNS-HLH) in the context of systemic disease, as well as when CNS features occur in isolation. We present the reader with a diagnostic approach to CNS-HLH and commonly used treatment protocols. We discuss and evaluate newer treatments on the horizon.

Recent Findings

Mortality is high in patients who do not undergo HSCT, and while larger studies are required to establish benefit in many treatments, a number of new treatments are currently being evaluated. Alemtuzumab is being used as a first-line treatment for CNS-HLH in a phase I/II multicentre prospective clinical trial as an alternative to traditional HLH-1994 and 2004 protocols. It has also been used successfully as a second-line agent for the treatment of isolated CNS-HLH that is refractory to standard treatment. Ruxolitinib and emapalumab are new immunotherapies that block the Janus kinase—Signal Transducer and Activator of Transcription (JAK-STAT) pathway that have shown efficacy in refractory HLH, including for CNS-HLH disease.

Summary

Treatment of CNS-HLH often requires HLH-94 or 2004 protocols followed by haematopoietic stem cell transplantation (HSCT) to maintain remission, although relapse can occur, particularly with reduced intensity conditioning if donor chimerism falls. CNS features have been shown to improve or stabilise following HSCT in CNS-HLH in the context of systemic disease and in isolated CNS-HLH. Encouraging reports of early cohort studies suggest alemtuzumab and the Janus kinase (JAK) inhibitor ruxolitinib offer potential salvage therapy for relapsed and refractory CNS-HLH. Newer immunotherapies such as tocilizumab and natalizumab have been shown to be beneficial in sporadic cases. CNS-HLH due to primary gene defects may be amenable to gene therapy in the future.

2021 American College of Rheumatology Guideline for the Treatment of Juvenile Idiopathic Arthritis: Therapeutic Approaches for Oligoarthritis, Temporomandibular Joint Arthritis, and Systemic Juvenile Idiopathic Arthritis

OBJECTIVE

To provide updated guidelines for pharmacologic management of juvenile idiopathic arthritis (JIA), focusing on treatment of oligoarthritis, temporomandibular joint (TMJ) arthritis, and systemic JIA with and without macrophage activation syndrome. Recommendations regarding tapering and discontinuing treatment in inactive systemic JIA are also provided.

METHODS

We developed clinically relevant Patient/Population, Intervention, Comparison, and Outcomes questions. After conducting a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation approach was used to rate the quality of evidence (high, moderate, low, or very low). A Voting Panel including clinicians and patients/caregivers achieved consensus on the direction (for or against) and strength (strong or conditional) of recommendations.

RESULTS

Similar to those published in 2019, these JIA recommendations are based on clinical phenotypes of JIA, rather than a specific classification schema. This guideline provides recommendations for initial and subsequent treatment of JIA with oligoarthritis, TMJ arthritis, and systemic JIA as well as for tapering and discontinuing treatment in subjects with inactive systemic JIA. Other aspects of disease management, including factors that influence treatment choice and medication tapering, are discussed. Evidence for all recommendations was graded as low or very low in quality. For that reason, more than half of the recommendations are conditional.

CONCLUSION

This clinical practice guideline complements the 2019 American College of Rheumatology JIA and uveitis guidelines, which addressed polyarthritis, sacroiliitis, enthesitis, and uveitis. It serves as a tool to support clinicians, patients, and caregivers in decision-making. The recommendations take into consideration the severity of both articular and nonarticular manifestations as well as patient quality of life. Although evidence is generally low quality and many recommendations are conditional, the inclusion of caregivers and patients in the decision-making process strengthens the relevance and applicability of the guideline. It is important to remember that these are recommendations. Clinical decisions, as always, should be made by the treating clinician and patient/caregiver.

Central nervous system involvement and thrombocytopenia as predictors of mortality in children with hemophagocytic lymphohistiocytosis

INTRODUCTION

Hemophagocytic lymphohistiocytosis (HLH) is a potentially life-threatening condition. This study aimed to evaluate treatment outcomes and identify prognostic-related factors in Thai children with HLH.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 76 pediatric patients with HLH who were treated at Ramathibodi Hospital between January 2004 and December 2019. Treatment outcomes were defined as early mortality (death within 30 days after diagnosis) and early treatment response (resolution of all clinical features and normalization of at least one HLH-related laboratory parameter within 4 weeks).

RESULTS

The overall mortality rate was 38% (29/76), with an early mortality rate of 45% (13/29). Malignancy-associated HLH had the highest mortality rate (88%), followed by primary HLH (56%). The predictors of early mortality were central nervous system (CNS) involvement [OR 13 (95%CI 2-83), p = 0.007] and platelet counts <44 × 10⁶/mm³ [OR 8 (95%CI 1.3-49), p = 0.024]. The predictors of early treatment response were no CNS involvement [OR 6.6 (95%CI 1.5-28.8), p = 0.011], platelet counts more than 44 × 10⁶/mm³ [OR 8 (95%CI 2.1-30.9), p = 0.003], and total bilirubin levels <1.8 mg/dL [OR 4 (95%CI 1.1-14.8), p = 0.036]. In the mixed-model analysis, platelet counts in non-survivors increased significantly less than those in survivors, with a mean difference in platelet changes between the two groups of 94.6 × 10⁶/mm³ (p = 0.003).

CONCLUSION

The independent predictors of early mortality in children with HLH were CNS involvement and low baseline platelet counts. A slow rate of platelet increases during the first week after diagnosis was also associated with mortality.

Pathogenesis and Treatment of Refractory Disease Courses in Systemic Juvenile Idiopathic Arthritis: Refractory Arthritis, Recurrent Macrophage Activation Syndrome and Chronic Lung Disease

Systemic juvenile idiopathic arthritis is a distinct and heterogeneous disease presently classified under the umbrella of juvenile idiopathic arthritis, with some patients following a monophasic remitting course, whereas others have persistent disease with chronic organ- and life-threatening complications. Although biologic therapies have revolutionized treatment, recent follow-up studies report significant numbers of children with persistently active disease on long term follow-up. This review focuses on refractory disease courses, specifically refractory arthritis, systemic juvenile idiopathic arthritis with recurrent, or longstanding signs of macrophage activation syndrome, and systemic juvenile idiopathic arthritis associated with suspected, probable, or definite lung disease.

Intravenous administration of anakinra in children with macrophage activation syndrome

BACKGROUND

Subcutaneous anakinra is an interleukin-1 inhibitor used to treat juvenile idiopathic arthritis. Recent reports suggest anakinra can be a valuable addition to the treatment of COVID-19 associated cytokine storm syndrome and the related multisystem inflammatory syndrome (MIS-C) in children. Herein, we describe our experience with intravenously administered anakinra.

FINDINGS

19 Patients (9 male) received intravenous (IV) anakinra for treatment of macrophage activation syndrome (MAS) secondary to systemic lupus erythematosus (SLE), systemic JIA (SJIA) or secondary hemophagocytic lymphohistiocytosis (sHLH). In most cases the general trend of the fibrinogen, ferritin, AST, and platelet count (Ravelli criteria) improved after initiation of IV anakinra. There were no reports of anaphylaxis or reactions associated with administration of IV anakinra.

CONCLUSION

Intravenous administration of anakinra is an important therapeutic option for critically ill patients with MAS/HLH. It is also beneficial for those with thrombocytopenia, subcutaneous edema, neurological dysfunction, or very young, hospitalized patients who need multiple painful subcutaneous injections.

Macrophage Activation Syndrome in Pediatric Systemic Lupus Erythematosus: A Systematic Review of the Diagnostic Aspects

Macrophage Activation Syndrome (MAS) is a very severe complication of different rheumatic diseases, including pediatric Systemic Lupus Erythematosus (pSLE). MAS is not considered as a frequent complication of pSLE; however, its occurrence could be under-estimated and the diagnosis can be challenging. In order to address this issue, we performed a systematic review of the available medical literature, aiming to retrieve all those papers providing diagnostic (clinical/laboratory) data on patients with pSLE-related MAS, in individual or aggregated form. The selected case reports and series provided a pool of 46 patients, accounting for 48 episodes of MAS in total. We re-analyzed these patients in light of the diagnostic criteria for MAS validated in systemic Juvenile Idiopathic Arthritis (sJIA) patients and the preliminary diagnostic criteria for MAS in pSLE, respectively. Five clinical studies were also selected and used to support this analysis. This systematic review confirms that MAS diagnosis in pSLE patients is characterized by several diagnostic challenges, which could lead to delayed diagnosis and/or under-estimation of this complication. Specific criteria should be considered to diagnose MAS in different rheumatic diseases; as regards pSLE, the aforementioned preliminary criteria for MAS in pSLE seem to perform better than the sJIA-related MAS criteria, because of a lower ferritin cut-off.

Allogeneic Hematopoietic Cell Transplant for Systemic Juvenile Idiopathic Arthritis and Macrophage Activation Syndrome

Systemic juvenile idiopathic arthritis (sJIA) is characterized by arthritis, fever, rash, lymphadenopathy, hepatosplenomegaly, and serositis. Macrophage activation syndrome is the most feared complication of sJIA with a high risk of mortality. We report a 16-year-old female diagnosed with refractory systemic juvenile idiopathic arthritis (sJIA) complicated by recurrent macrophage activation syndrome (MAS), severe joint disease, and lung involvement requiring prolonged immunosuppressive therapy. She received a matched unrelated allogeneic hematopoietic cell transplant (Allo-HCT) using a reduced-intensity conditioning regimen and is now, 3 years after the transplant, with complete resolution of sJIA symptoms, off immunosuppressants, and with significant improvement in the quality of life.

Macrophage activation syndrome in systemic lupus erythematosus and systemic-onset juvenile idiopathic arthritis: a retrospective study of similarities and dissimilarities

Macrophage activation syndrome (MAS) is a serious complication of rheumatic diseases. Fever and hyperferritinemia are common in active systemic-onset juvenile idiopathic arthritis (sJIA) and cytopenia in active systemic lupus erythematosus (SLE), thus recognizing MAS in them is a challenge. We compared clinical and laboratory parameters, various classification criteria, and outcomes of MAS in SLE and sJIA. Clinical and laboratory data were extracted from case records of patients with clinician diagnosed cases of SLE-MAS (adult and pediatric) and sJIA-MAS, admitted (2004-2018) at a tertiary care hospital. Ravelli, International consensus, HLH-2004, and criteria proposed by Parodi et al. were applied and compared. Among 33 patients (18 females) with MAS, 19 had SLE (7, childhood-onset SLE) and 14 had sJIA. MAS was more likely to be the presenting manifestation of disease in SLE (p < 0.05). There were no differences in the clinical features among them. Patients with SLE-MAS had lower baseline total leucocyte and platelet counts (p < 0.01), whereas patients with sJIA-MAS had significantly higher median CRP (p = 0.002), fall in TLC (p = 0.012), delta ESR/CRP ratio (p = 0.02), and lower fibrinogen level (p = 0.006). Neutrophil-to-lymphocyte ratio, ferritin/CRP ratio, and the number of patients with ferritin/ESR > 80 were similar. Only 6/33(18%) fulfilled the HLH criteria. Criteria meant for sJIA-MAS or SLE-MAS performed well for both diseases and the majority of patients could be diagnosed using them. Two patients died in each group. MAS in SLE and sJIA is more similar than dissimilar in clinical features and outcome. Criteria meant for MAS in sJIA or SLE-MAS performed equally well in both diseases.

Case Report: Macrophage Activation Syndrome and Widespread Neuroimaging Abnormality in Childhood-Onset Systemic Lupus Erythematosus

Macrophage activation syndrome (MAS) and widespread brain lesions are rare and severe complications of childhood-onset systemic lupus erythematosus (SLE). We report an 11-year-old girl who presented with recurrent rashes for half a year and fever for 2 weeks. Clinical and laboratory features at admission pointed to the diagnosis of SLE and SLE-associated MAS. Cerebral magnetic resonance imaging taken on day 4 after admission showed abnormal signals. Glucocorticoid therapy was started on day 5. Two days later, the patient appeared weak and ill, then the next day she exhibited dizziness, drowsiness, apathia, and dysarthria. High-dose methylprednisolone, cyclophosphamide, and intravenous immunoglobulin were used to treat the patient, and intrathecal dexamethasone was given. The patient was discharged on day 30 after admission and showed complete clinical resolution and improved magnetic resonance imaging resolution.

The off-label use of anakinra in pediatric systemic autoinflammatory diseases

Interleukin 1 (IL-1), a central mediator of innate immunity, is considered a master cytokine of local and systemic inflammation. IL-1 has emerged as pivotal in the pathogenesis of autoinflammatory diseases (AIDs), and blockade of its pathway has become a crucial target for therapy. Anakinra (ANA), a recombinant IL-1β receptor antagonist, was the first anti-IL-1 agent employed in clinical practice. ANA is currently approved for the treatment of rheumatoid arthritis, systemic juvenile idiopathic arthritis, adult-onset Still’s disease, and cryopyrin-associated autoinflammatory syndrome. It has also been successfully used for off-label treatment of various monogenic, polygenic, or undefined etiology systemic AIDs.

This review describes currently available evidence for the off-label use of ANA in pediatric rheumatologic diseases. Specifically, the use of ANA in Kawasaki disease, idiopathic recurrent pericarditis, Behçet disease, monogenic AIDs, undifferentiated AIDs, chronic non-bacterial osteomyelitis, macrophage activation syndrome, and febrile infection-related epilepsy, in terms of its safety and efficacy. In selected pediatric rheumatic disorders, the off-label administration of ANA appears to be effective and safe. In order to control severe and/or relapsing disease, ANA should be considered as a valuable treatment option in children suffering from rare inflammatory diseases. However, currently available data consist of retrospective studies and short case series; thus, randomized controlled trials and larger series with long-term follow up are mandatory to better assess the efficacy and cost effectiveness of ANA in these challenging patients.

Silencing the cytokine storm: the use of intravenous anakinra in haemophagocytic lymphohistiocytosis or macrophage activation syndrome

The term cytokine storm syndromes describes conditions characterised by a life-threatening, fulminant hypercytokinaemia with high mortality. Cytokine storm syndromes can be genetic or a secondary complication of autoimmune or autoinflammatory disorders, infections, and haematological malignancies. These syndromes represent a key area of interface between rheumatology and general medicine. Rheumatologists often lead in management, in view of their experience using intensive immunosuppressive regimens and managing cytokine storm syndromes in the context of rheumatic disorders or infection (known as secondary haemophagocytic lymphohistiocytosis or macrophage activation syndrome [sHLH/MAS]). Interleukin (IL)-1 is pivotal in hyperinflammation. Anakinra, a recombinant humanised IL-1 receptor antagonist, is licenced at a dose of 100 mg once daily by subcutaneous injection for rheumatoid arthritis, systemic juvenile idiopathic arthritis, adult-onset Still's disease, and cryopyrin-associated periodic syndromes. In cytokine storm syndromes, the subcutaneous route is often problematic, as absorption can be unreliable in patients with critical illness, and multiple injections are needed to achieve the high doses required. As a result, intravenous anakinra is used in clinical practice for sHLH/MAS, despite this being an off-licence indication and route of administration. Among 46 patients admitted to our three international, tertiary centres for sHLH/MAS and treated with anakinra over 12 months, the intravenous route of delivery was used in 18 (39%) patients. In this Viewpoint, we describe current challenges in the management of cytokine storm syndromes and review the pharmacokinetic and safety profile of intravenous anakinra. There is accumulating evidence to support the rationale for, and safety of, intravenous anakinra as a first-line treatment in patients with sHLH/MAS. Intravenous anakinra has important clinical relevance when high doses of drug are required or if patients have subcutaneous oedema, severe thrombocytopenia, or neurological involvement. Cross-speciality management and collaboration, with the generation of international, multi-centre registries and biobanks, are needed to better understand the aetiopathogenesis and improve the poor prognosis of cytokine storm syndromes.

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.

Clinical features and outcomes of patients with hemophagocytic lymphohistiocytosis at onset of systemic autoinflammatory disorder and compare with Epstein-Barr virus (EBV)-related hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease. In clinical practice, we have observed that some HLH patients who have features of systemic autoinflammatory diseases (SAIDs) exhibit unique clinical manifestations and outcomes different from other HLH patients.We analyzed data from 25 HLH patients who were considered to have SAIDs; data were collected from patients of our center between January 1, 2015 and September 1, 2018.The median age of the patients was 1.75 years. In the early phase, all patients had a fever and 92% of patients had a rash; 96% of patients had high white blood cell count (WBC), C-reaction protein, and erythrocyte sedimentation rate. With progression, the above laboratory results decreased gradually. During the HLH period, we compared SAIDs-related HLH and Epstein-Barr virus (EBV)-related HLH and found that rash was more common (92%, P < .001) and splenomegaly was less common (64%, P = .023) in SAIDs-related HLH. Further, WBC, ferritin, and Interleukin-6 levels in SAIDs-related HLH patients were higher than those in EBV-related HLH patients. In contrast, hemoglobin, triglyceride, sCD25, Interleukin-10, and interferon-γ levels in SAIDs-related HLH patients were lower compared with those in EBV-related HLH patients. SAIDs-related HLH patients received a modified HLH-2004 protocol at our center. Most patients had a good prognosis.We provide a summary of the unique clinical and laboratory features, treatment protocols, and outcomes of SAIDs patients with HLH at onset. The findings indicate that these patients had a better response to corticosteroids and cyclosporin compared with EBV-related HLH patients.

Benefit of Anakinra in Treating Pediatric Secondary Hemophagocytic Lymphohistiocytosis

OBJECTIVE

To assess the benefit of the recombinant human interleukin-1 receptor antagonist anakinra in treating pediatric patients with secondary hemophagocytic lymphohistiocytosis (HLH)/macrophage activation syndrome (MAS) associated with rheumatic and nonrheumatic conditions.

METHODS

A retrospective chart review of all anakinra-treated patients with secondary HLH/MAS was performed at Children's of Alabama from January 2008 through December 2016. Demographic, clinical, laboratory, and genetic characteristics, outcomes data, and information on concurrent treatments were collected from the records and analyzed using appropriate univariate statistical approaches to assess changes following treatment and associations between patient variables and outcomes.

RESULTS

Forty-four patients with secondary HLH/MAS being treated with anakinra were identified in the electronic medical records. The median duration of hospitalization was 15 days. The mean pretreatment serum ferritin level was 33,316 ng/ml and dropped to 14,435 ng/ml (57% decrease) within 15 days of the start of anakinra treatment. The overall mortality rate in the cohort was 27%. Earlier initiation of anakinra (within 5 days of hospitalization) was associated with reduced mortality (P = 0.046), whereas thrombocytopenia (platelet count <100,000/μl) and STXBP2 mutations were both associated with increased mortality (P = 0.008 and P = 0.012, respectively). In considering patients according to their underlying diagnosis, those with systemic juvenile idiopathic arthritis (JIA) had the lowest mortality rate, with no deaths among the 13 systemic JIA patients included in the study (P = 0.006). In contrast, those with an underlying hematologic malignancy had the highest mortality rate, at 100% (n = 3).

CONCLUSION

These findings suggest that anakinra appears to be effective in treating pediatric patients with non-malignancy-associated secondary HLH/MAS, especially when it is given early in the disease course and when administered to patients who have an underlying rheumatic disease.

[What are the indications for rescue procedures? : Systemic rheumatic diseases in the intensive care unit]

Schwere, organ- oder lebensbedrohliche Manifestationen entzündlicher rheumatischer Erkrankungen, wie z. B. eine diffuse alveoläre Hämorrhagie im Rahmen einer Kleingefäßvaskulitis, sprechen nicht immer ausreichend oder mit zeitlicher Verzögerung auf eine immunsuppressive Therapie an. Bei einem drohenden oder bereits eingetretenen Organversagen besteht dann nicht selten die Notwendigkeit, die immunsuppressive Therapie auf der Intensivstation um rasch wirksame Rescue-Therapieverfahren zu ergänzen. Aufgrund der Seltenheit vieler rheumatischer Erkrankungen ist die Evidenz zum Einsatz von Rescue-Therapieverfahren wie der Plasmapherese, der extrakorporalen Membranoxygenierung (ECMO) oder der Gabe von intravenösen Immunglobulinen (IVIG) für viele Indikationen eher gering. Der Einsatz der Plasmapherese wird bei einer akuten Anti-GBM(glomeruläre Basalmembran)-Erkrankung (Goodpasture Syndrom) oder einem katastrophalen Antiphospholipidantikörpersyndrom (CAPS) als sinnvoll angesehen. Eine ECMO-Therapie kann bei persistierender respiratorischer Insuffizienz trotz mechanischer Beatmung als Folge einer diffusen alveolären Hämorrhagie oder eines Acute-Respiratory-Distress-Syndroms (ARDS) anderer Ursache erwogen werden. Eine Gabe von IVIG ist bei einer akuten kardialen Beteiligung im Rahmen einer Kawasaki-Erkrankung indiziert und kann beim CAPS sowie bei therapierefraktären Myositiden erwogen werden.

Fatal Myocarditis in an Adolescent Girl with Evolving Connective Tissue Disease

Connective tissue diseases are rarely suspected and diagnosed in childhood and adolescence. Rarity of occurrence and poor disease acceptance among parents make them extremely difficult to treat in the early stages. An adolescent girl presented with features of pneumonia, was worked up and diagnosed as an evolving connective tissue disease. Her clinical characteristics did not fit into any specific disease. She was started on steroids and immunoglobulin as she had fulminant myocarditis with rapid downhill clinical course. High index of suspicion and aggressive immunosuppression can be life saving in exceptional situations even though a specific diagnosis cannot be ascertained.

Clinical features of macrophage activation syndrome as the onset manifestation of juvenile systemic lupus erythematosus

Objectives

Macrophage activation syndrome (MAS) is a severe complication of juvenile systemic lupus erythematosus (jSLE). However, little is known about the association between these conditions, especially in terms of MAS as the initial manifestation of jSLE. The aim of this study was to determine the clinical features of MAS as the initial manifestation of jSLE.

Methods

We carried out a retrospective review of the clinical features of MAS cases diagnosed concomitantly with jSLE from 2004 to 2016. Data from these patients were compared with those from a control group consisting of jSLE patients without MAS.

Results

Eleven (23.9%) of the 46 patients recruited for this study were diagnosed with MAS during the initial stage of jSLE. The between-group comparisons demonstrated that fever, leucopenia, hyperferritinaemia and increased aspartate aminotransferase were more frequently observed in jSLE patients with MAS than in controls (P<0.01). Importantly, neurological symptoms were significantly more common in patients with MAS than in controls (P<0.01), with 6 (54.6%) of the 11 MAS patients affected. For treatment, all 11 patients with both jSLE and MAS were administered CSs upon diagnosis, and 7 received immunosuppressants. No patient involved in this study died.

Conclusion

MAS can develop as the initial manifestation of jSLE. MAS with jSLE should be suspected in patients with fever, hyperferritinaemia, cytopenia and liver disorder. In addition, we found that jSLE patients with MAS had more neurological symptoms than those without. All patients with MAS were successfully treated with CSs. Early diagnosis and intensive therapy are essential in improving clinical outcomes.

Anakinra treatment in macrophage activation syndrome: a single center experience and systemic review of literature

Our aim was to report our experiences of pediatric macrophage activation syndrome (MAS) patients treated with anakinra and to review previous studies reporting anakinra treatment in pediatric MAS patients associated with systemic juvenile idiopathic arthritis (sJIA) or autoinflammatory diseases (AIDs). The study group consisted of pediatric MAS patients due to sJIA or AIDs, followed up in the Pediatric Rheumatology Unit of Hacettepe University between January 2015 and January 2017 and treated with anakinra (anti-IL1). We conducted a systematic review of the published literature involving pediatric MAS patients associated with sJIA or AIDs, treated with anakinra. Thirteen sJIA patients and two AIDs patients were included the study. Nineteen MAS episodes were observed in 15 patients. Anakinra (2 mg/kg/day) was started in with a median 1 day after admission. Clinical symptoms resolved, and laboratory findings normalized within median (minimum-maximum) 2 (1-4) and 6 (4-9) days, respectively after the introduction of anakinra. Steroid treatment was stopped in a median of 10 (4-13) weeks after the initiation of anakinra treatment. Patients were followed up for a median of 13 (6-24) months. Two patients developed recurrent MAS episodes when the anakinra dose was reduced, while the other patients achieved remission. In the literature review, we identified nine articles, describing 35 pediatric MAS patients associated with sJIA or AIDs and treated with anakinra. Except for two, all the patients reached remission. Our study and systematic literature review may help to improve the knowledge on the role of anakinra treatment in the management of MAS.

Glucocorticoid treatment in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease of joints in childhood. Glucocorticoids are being used in JIA treatment effectively for decades. Although systemic glucocorticoid use decreased with the introduction of biologic drugs, intraarticular glucocorticoid injections (IAGI) with nonsteroidal anti-inflammatory drugs and non-biologic disease modifying anti-rheumatic drugs (DMARDs) still remain the primary treatment in JIA, especially in oligoarticular subcategory. Systemic glucocorticoids are used mainly for severe JIA-associated complications such as macrophage activation syndrome (MAS), myocarditis, pericarditis, pleuritis, peritonitis, and severe anemia; as bridging therapy while waiting for the full therapeutic effect of DMARDs; and in certain occasions for patients with severe refractory uveitis. Since glucocorticoid administration is associated with many adverse events, it is important to use glucocorticoids in an optimum way balancing the risks and benefits. The aim of this review is to summarize the current knowledge on glucocorticoid treatment in JIA. A comprehensive literature search was conducted utilizing the Cochrane Library and MEDLINE/PubMed databases. The main topics include mechanism of action, dose, duration, adverse events, vaccination during glucocorticoid treatment, the place of glucocorticoids in JIA treatment guidelines and consensus treatment plans, glucocorticoid use in JIA-associated uveitis, MAS, and IAGI. Data from the literature provide guidance on how to use glucocorticoids in JIA treatment especially for IAGI and systemic use in systemic JIA and MAS. However, there is lack of evidence and need for prospective randomized studies in most parts including the indications in different JIA subcategories, optimum dose/route of administration/duration of treatment, and tapering strategies.

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.

Macrophage Activation Syndrome: A Report of Two Cases and a Literature Review

Macrophage activation syndrome (MAS) is a severe, potentially fatal condition that may complicate autoimmune diseases, and it belongs to hemophagocytic lymphohistiocytosis (HLH) disorders. MAS occurs in adults and children. However, it is rare in juvenile systemic lupus erythematosus (jSLE), and it is extremely rare to be the initial presentation of jSLE. Here, we report two patients with juvenile SLE who initially presented with MAS. One of the two patients is 4 years old. This is the youngest reported patient to our knowledge.

Treatment of adult-onset still's disease: up to date

INTRODUCTION

Adult onset Still's disease (AOSD) is a systemic inflammatory disorder of unknown etiology, and approximately 60-70% of patients may develop a chronic polyphasic form of the disease or a chronic polyarthritis. Due to rarity of disease, treatment of AOSD is not based on controlled study, but on case based experiences. Areas covered: Recently, the application of anti-cytokine therapy based on pathophysiology has resulted in significant progress in the treatment of AOSD. Here, we review current knowledge of the pathogenesis, disease progression, currently available biomarkers of disease activity, standard therapeutic agents, utility of biologic agents, future perspectives for treatment and treatment of macrophage activation syndrome. Expert commentary: Accumulated clinical data suggest that chronic disease can be classified into two subsets: dominant systemic disease, and the arthritis subgroup. IL-1 inhibitors may be more efficient for systemic manifestations and IL-6 inhibitor for both joint involvement and systemic manifestations. TNF inhibitors must be reserved for patients with purely chronic articular manifestations. For ideal management of patients, it is very important to measure disease activity accurately during follow up, but no single biomarker has been classified as ideal. New therapeutic agents and composite biomarkers are needed to improve the outcome of patients with AOSD by identifying disease activity properly.

Oxidized Low-Density Lipoprotein Immune Complex Priming of the Nlrp3 Inflammasome Involves TLR and FcγR Cooperation and Is Dependent on CARD9

Oxidized low-density lipoprotein (oxLDL) is known to activate inflammatory responses in a variety of cells, especially macrophages and dendritic cells. Interestingly, much of the oxLDL in circulation is complexed to Abs, and these resulting immune complexes (ICs) are a prominent feature of chronic inflammatory disease, such as atherosclerosis, type-2 diabetes, systemic lupus erythematosus, and rheumatoid arthritis. Levels of oxLDL ICs often correlate with disease severity, and studies demonstrated that oxLDL ICs elicit potent inflammatory responses in macrophages. In this article, we show that bone marrow-derived dendritic cells (BMDCs) incubated with oxLDL ICs for 24 h secrete significantly more IL-1β compared with BMDCs treated with free oxLDL, whereas there was no difference in levels of TNF-α or IL-6. Treatment of BMDCs with oxLDL ICs increased expression of inflammasome-related genes Il1a, Il1b, and Nlrp3, and pretreatment with a caspase 1 inhibitor decreased IL-1β secretion in response to oxLDL ICs. This inflammasome priming was due to oxLDL IC signaling via multiple receptors, because inhibition of CD36, TLR4, and FcγR significantly decreased IL-1β secretion in response to oxLDL ICs. Signaling through these receptors converged on the adaptor protein CARD9, a component of the CARD9-Bcl10-MALT1 signalosome complex involved in NF-κB translocation. Finally, oxLDL IC-mediated IL-1β production resulted in increased Th17 polarization and cytokine secretion. Collectively, these data demonstrate that oxLDL ICs induce inflammasome activation through a separate and more robust mechanism than oxLDL alone and that these ICs may be immunomodulatory in chronic disease and not just biomarkers of severity.

Lung Involvement in Children with Hereditary Autoinflammatory Disorders

Short-lived systemic inflammatory reactions arising from disrupted rules in the innate immune system are the operating platforms of hereditary autoinflammatory disorders (HAIDs). Multiple organs may be involved and aseptic inflammation leading to disease-specific phenotypes defines most HAIDs. Lungs are infrequently involved in children with HAIDs: the most common pulmonary manifestation is pleuritis in familial Mediterranean fever (FMF) and tumor necrosis factor receptor-associated periodic syndrome (TRAPS), respectively caused by mutations in the MEFV and TNFRSF1A genes, while interstitial lung disease can be observed in STING-associated vasculopathy with onset in infancy (SAVI), caused by mutations in the TMEM173 gene. The specific pleuropulmonary diseases may range from sub-clinical abnormalities during inflammatory flares of FMF and TRAPS to a severe life-threatening disorder in children with SAVI.