Review: Macrophage activation syndrome in juvenile systemic lupus erythematosus: an under-recognized complication?

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

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

The 2022 EULAR/ACR Points to Consider at the Early Stages of Diagnosis and Management of Suspected Haemophagocytic Lymphohistiocytosis/Macrophage Activation Syndrome (HLH/MAS)

OBJECTIVE

Haemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are life-threatening systemic hyperinflammatory syndromes that can develop in most inflammatory contexts. They can progress rapidly, and early identification and management are critical for preventing organ failure and mortality. This effort aimed to develop evidence-based and consensus-based points to consider to assist clinicians in optimising decision-making in the early stages of diagnosis, treatment and monitoring of HLH/MAS.

METHODS

A multinational, multidisciplinary task force of physician experts, including adult and paediatric rheumatologists, haematologist/oncologists, immunologists, infectious disease specialists, intensivists, allied healthcare professionals and patients/parents, formulated relevant research questions and conducted a systematic literature review (SLR). Delphi methodology, informed by SLR results and questionnaires of experts, was used to generate statements aimed at assisting early decision-making and optimising the initial care of patients with HLH/MAS.

RESULTS

The task force developed 6 overarching statements and 24 specific points to consider relevant to early recognition of HLH/MAS, diagnostic approaches, initial management and monitoring of HLH/MAS. Major themes included the simultaneous need for prompt syndrome recognition, systematic evaluation of underlying contributors, early intervention targeting both hyperinflammation and likely contributors, careful monitoring for progression/complications and expert multidisciplinary assistance.

CONCLUSION

These 2022 EULAR/American College of Rheumatology points to consider provide up-to-date guidance, based on the best available published data and expert opinion. They are meant to help guide the initial evaluation, management and monitoring of patients with HLH/MAS in order to halt disease progression and prevent life-threatening immunopathology.

The 2022 EULAR/ACR points to consider at the early stages of diagnosis and management of suspected haemophagocytic lymphohistiocytosis/macrophage activation syndrome (HLH/MAS)

OBJECTIVE

Haemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are life-threatening systemic hyperinflammatory syndromes that can develop in most inflammatory contexts. They can progress rapidly, and early identification and management are critical for preventing organ failure and mortality. This effort aimed to develop evidence-based and consensus-based points to consider to assist clinicians in optimising decision-making in the early stages of diagnosis, treatment and monitoring of HLH/MAS.

METHODS

A multinational, multidisciplinary task force of physician experts, including adult and paediatric rheumatologists, haematologist/oncologists, immunologists, infectious disease specialists, intensivists, allied healthcare professionals and patients/parents, formulated relevant research questions and conducted a systematic literature review (SLR). Delphi methodology, informed by SLR results and questionnaires of experts, was used to generate statements aimed at assisting early decision-making and optimising the initial care of patients with HLH/MAS.

RESULTS

The task force developed 6 overarching statements and 24 specific points to consider relevant to early recognition of HLH/MAS, diagnostic approaches, initial management and monitoring of HLH/MAS. Major themes included the simultaneous need for prompt syndrome recognition, systematic evaluation of underlying contributors, early intervention targeting both hyperinflammation and likely contributors, careful monitoring for progression/complications and expert multidisciplinary assistance.

CONCLUSION

These 2022 EULAR/American College of Rheumatology points to consider provide up-to-date guidance, based on the best available published data and expert opinion. They are meant to help guide the initial evaluation, management and monitoring of patients with HLH/MAS in order to halt disease progression and prevent life-threatening immunopathology.

A Case of Macrophage Activation Syndrome Manifesting as the Initial Presentation of Systemic Lupus Erythematosus

Macrophage activation syndrome (MAS) is a potentially fatal complication of an autoimmune rheumatologic disease characterized by overwhelming inflammation, multiorgan failure, and high mortality if untreated. We report a rare case of a 56-year-old man who presented with fever for three weeks and had a constellation of clinical features and laboratory findings, meeting the diagnostic criteria for systemic lupus erythematosus (SLE) and SLE-associated MAS. He was treated with high dose intravenous corticosteroid and hydroxychloroquine, resulting in resolution of fever and dramatic clinical improvement.

Recurrent macrophage activation syndrome as the initial manifestation of paediatric systemic lupus erythematosus

Introduction: Macrophage Activation Syndrome (MAS) is a rare but potentially fatal complication in rheumatic diseases. Here, we report the case of a 14-year-old girl with MAS as the primary manifestation of Systemic Lupus Erythematosus (SLE). She had three episodes of MAS during the course of her treatment. This case is unique as recurrent MAS in pediatric SLE is rare.Methods: Demographic, clinical, laboratory features and outcomes of our patient was noted. We also reviewed the two reported cases of recurrent MAS in pediatric SLE. Literature review was performed on PubMed search forum. Search items included Macrophage activation syndrome, pediatric systemic lupus erythematosus, recurrent MAS.Conclusion: The diagnosis and management of MAS are challenging as it can simulate an infectious complication or can be the exacerbation of the underlying disease. Early detection and prompt treatment can reduce morbidity in these patients.

Synergistic Signaling of TLR and IFNα/β Facilitates Escape of IL-18 Expression from Endotoxin Tolerance

Rationale: IL-18 is a member of the IL-1 cytokine family, and elevated blood IL-18 concentrations associate with disease activity in macrophage activation syndrome (MAS) and poor clinical outcomes in severe inflammatory and septic conditions.

Objectives: Although recent investigations provide mechanistic evidence for a contribution of IL-18 to inflammation and hyperinflammation in sepsis and MAS, we sought to study regulatory mechanisms underlying human IL-18 expression.

Methods: Samples from in vivo and in vitro endotoxin rechallenge experiments, patients with inflammatory disease, and isolated human monocytes treated with various stimulants and drugs were tested for cytokine gene and protein expression. Serum IL-18 expression with or without JAK/STAT inhibition was analyzed in two MAS mouse models and in a patient with recurrent MAS.

Measurements and Main Results: Peripheral blood and monocytic IL-18 expression escaped LPS-induced immunoparalysis. LPS-stimulated primary human monocytes revealed specific IL-18 expression kinetics controlled by IFNα/β signaling. JAK/STAT inhibition or IFNβ neutralization during LPS stimulation blunted cytokine expression. Similarly, microtubule-destabilizing drugs abrogated LPS-induced IL18 expression, but this effect could be fully reversed by addition of IFNα/β. Ex vivo analysis of inflammatory disease patients’ whole blood revealed strong correlation of type I IFN score and IL18 expression, whereas JAK/STAT inhibition strongly reduced IL-18 serum levels in two MAS mouse models and in a patient with recurrent MAS.

Conclusions: Our data indicate that IL-18 (but not IL-1β) production from human monocytes requires cooperative Toll-like receptor and IFNα/β signaling. Interference with IFNα/β expression or signaling following JAK/STAT inhibition may control catastrophic hyperinflammation in MAS.

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.

Extensive serum biomarker analysis in patients with macrophage activation syndrome associated with systemic lupus erythematosus

The present study employed an antibody array that simultaneously detects 174 cytokines to identify cytokines involved in the development of macrophage activation syndrome (MAS) associated with systemic lupus erythematosus (SLE) with a view to elucidating potential predictive markers. Eight SLE patients, including four with MAS, were analyzed. Levels of 31 cytokines were significantly elevated in the MAS phase compared with those in the active phase of SLE. Among these cytokines, the MAS/active phase ratios of CXCL9 and soluble tumor necrosis factor receptor II (sTNFR-II) were highest. Elevated serum CXCL9 and sTNFR-II levels during the MAS phase were confirmed by ELISA and were strongly correlated with other inflammatory markers, reflecting the disease activity of MAS associated with SLE. These results highlight the clinical significance of serum CXCL-9 and sTNFR-II levels, and indicate they may be useful biomarkers for the diagnosis of MAS associated with SLE.

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.

Characteristics of bone marrow cells in 107 patients with juvenile idiopathic arthritis: A retrospective study

Few studies to date have reported on the myelodysplastic features of children with juvenile idiopathic arthritis (JIA). Bone marrow specimens were collected from 107 patients aged from 7-12 years who were initially diagnosed with JIA between May 2013 and October 2015. In 107 patients with JIA, bone marrow proliferation was higher than normal and hemophagocytes were more easily observed than usual. The characteristics of bone marrow cells in 107 patients with JIA were investigated and the associations of these characteristics with the disease was discussed in the present study. It was noticed that there were similar changes in the myeloid, erythropoietic and megakaryopoietic series in the majority of bone marrow specimens; the presence of hemophagocytes was also reported. The present findings suggest that JIA is associated with specific myelodysplastic changes, and that cellular immune system dysfunction and overreactive inflammatory cytokines may contribute to the development of these myelodysplastic changes in the bone marrow.

Macrophage Activation Syndrome

Hemophagocytic lymphohistiocytosis (HLH), or termed macrophage activation syndrome (MAS) when associated with rheumatic disorders, is a frequently fatal complication of infections, rheumatic disorders, and hematopoietic malignancies. Clinically, HLH/MAS is a life-threatening condition that is usually diagnosed among febrile hospitalized patients (children and adults) who commonly present with unremitting fever and a shock-like multiorgan dysfunction scenario. Laboratory studies reveal pancytopenia, elevated liver enzymes, elevated markers of inflammation (ESR, CRP), hyperferritinemia, and features of coagulopathy. In about 60% of cases, excess hemophagocytosis (macrophages/histiocytes engulfing other hematopoietic cell types) is noted on biopsy specimens from the bone marrow, liver, lymph nodes, and other organs. HLH/MAS has been hypothesized to occur when a threshold level of inflammation has been achieved, and genetic and environmental risk factors are believed to contribute to the hyperinflammatory state. A broad variety of infections, from viruses to fungi to bacteria, have been identified as triggers of HLH/MAS, either in isolation or in addition to an underlying inflammatory disease state. Certain infections, particularly by members of the herpesvirus family, are the most notorious triggers of HLH/MAS. Treatment for infection-triggered MAS requires therapy for both the underlying infection and dampening of the hyperactive immune response.

Features, Treatment, and Outcomes of Macrophage Activation Syndrome in Childhood-Onset Systemic Lupus Erythematosus

OBJECTIVE

To describe the features and treatment of macrophage activation syndrome (MAS) in a single-center cohort of patients with childhood-onset systemic lupus erythematosus (SLE), and to compare childhood-onset SLE manifestations and outcomes between those with and those without MAS.

METHODS

We included all patients with childhood-onset SLE followed up at The Hospital for Sick Children from 2002 to 2012, and identified those also diagnosed as having MAS. Demographic, clinical, and laboratory features of MAS and SLE, medication use, hospital and pediatric intensive care unit (PICU) admissions, as well as damage indices and mortality data were extracted from the Lupus database. Student's t-tests and Fisher's exact tests were used to compare continuous and categorical variables, respectively. We calculated incidence rate ratios of hospital and PICU admissions comparing patients with and those without MAS, using Poisson models. Kaplan-Meier survival analysis was used to examine the time to disease damage accrual.

RESULTS

Of the 403 patients with childhood-onset SLE, 38 (9%) had MAS. The majority (68%) had concomitant MAS and SLE diagnoses. Fever was the most common MAS clinical feature. The frequency of renal and central nervous system disease, hospital admissions, the average daily dose of steroids, and time to disease damage were similar between those with and those without MAS. We observed a higher mortality rate among those with MAS (5%) than those without MAS (0.2%) (P = 0.02).

CONCLUSION

MAS was most likely to develop concomitantly with childhood-onset SLE diagnosis. The majority of the MAS patients were successfully treated with corticosteroids with no MAS relapses. Although the numbers were small, there was a higher risk of death associated with MAS compared to SLE without MAS.

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.

Clinical spectrum and therapeutic management of systemic lupus erythematosus-associated macrophage activation syndrome: A study of 103 episodes in 89 adult patients

OBJECTIVES

Macrophage activation syndrome (MAS) is a life-threatening hyperinflammatory syndrome that can occur during systemic lupus erythematosus (SLE). Data on MAS in adult SLE patients are very limited. The aim of this study is to describe the clinical characteristics, laboratory findings, treatments, and outcomes of a large series of SLE-associated MAS.

METHODS

We conducted a retrospective study that included 103 episodes of MAS in 89 adult patients with SLE.

RESULTS

103 episodes in 89 adult patients were analyzed. Median age at first MAS episode was 32 (18-80) years. MAS was inaugural in 41 patients (46%).Thirteen patients relapsed. Patients had the following features: fever (100% episodes), increased serum levels of AST (94.7%), LDH (92.3%), CRP (84.5%), ferritin (96%), procalcitonin (41/49 cases). Complications included myocarditis (n=22), acute lung injury (n=15) and seizures (n=11). In 33 episodes, patients required hospitalization in an ICU and 5 died. Thrombocytopenia and high CRP levels were associated independently with an increased risk for ICU admission. High dose steroids alone as first line therapy induced remission in 37/57 cases (65%). Additional medications as first or second line therapies included IV immunoglobulins (n=22), cyclophosphamide (n=23), etoposide (n=11), rituximab (n=3). Etoposide and cyclophosphamide-based regimens had the best efficacy.

CONCLUSION

MAS is a severe complication and is often inaugural. High fever and high levels of AST, LDH, CRP, ferritin and PCT should be considered as red flags for early diagnosis. High dose steroids lead to remission in two third of cases. Cyclophosphamide or etoposide should be considered for uncontrolled/severe forms.

Evaluation of macrophage activation syndrome associated with systemic juvenile idiopathic arthritis: single center experience over a one-year period

AIM

This study aimed to evaluate the demographic, clinical, laboratory properties of patients with macrophage activation syndrome and treatment outcomes.

MATERIAL AND METHODS

The data of the patients who were diagnosed with macrophage activation syndrome secondary to systemic juvenile idiopathic arthritis between June 2013-May 2014 were evaluated by screening patient records.

RESULTS

Ten patients with macrophage activation syndrome were followed up in one year. The mean age at the time of diagnosis was found to be 7.6±4.5 years. The most common clinical finding at presentation (80%) was increased body temperature. Hepatosplenomegaly was found in half of the patients. The most common hematological finding (90%) was anemia. The mean erythrocyte sedimentation rate was found to be 71.8±36.2 mm/h, whereas it was measured to be lower (31.2±25.2 mm/h) at the time of the diagnosis of macrophage activation syndrome. Increased ferritin level was found in all of our patients (the mean ferritin level was found to be 23 957±15 525 ng/mL). Hypertriglyceridemia was found in nine patients (90%). The mean triglyceride level was found to be 397±332 mg/dL. Systemic steroid treatment was administered to all patients. Cyclosporine A was given to eight patients (80%), canakinumab was given to four patients (40%) and anakinra was given to five patients (50%). Plasmapheresis was performed in two patients. Improvement was found in all patients except for one patient. The patient in whom no improvement was observed showed a chronic course.

CONCLUSIONS

The diagnosis of macrophage activation syndrome should be considered in presence of sudden disturbance in general condition, resistant high fever and systemic inflammation findings in children with active rheumatic disease. Complete recovery can be provided with early and efficient treatment in macrophage activation syndrome which develops secondary to systemic juvenil idiopathic arthritis.

Macrophage activation syndrome: A severe and frequent manifestation of acute pancreatitis in 362 childhood-onset compared to 1830 adult-onset systemic lupus erythematosus patients

OBJECTIVE

We previously reported a case series of acute pancreatitis (AP) and macrophage activation syndrome (MAS) in childhood (cSLE) patients; however, there are no data regarding the comparison of AP and MAS in large populations of cSLE and adult SLE (aSLE).

METHODS

A study included 362 cSLE and 1830 aSLE patients. MAS was diagnosed according to preliminary diagnostic guidelines and AP according to the presence of abdominal pain or vomiting associated to an increase of pancreatic enzymes and/or pancreatic radiological abnormalities. Demographic data, clinical features, SLEDAI-2K, SLICC/ACR-DI, and treatment were assessed.

RESULTS

Age in MAS patients was significantly lower compared with those without this complication [15 (8.8-55) vs. 33.5 (10.2-45.7) years, p = 0.007]. The frequencies of fever (94% vs. 37%, p = 0.001), leucopenia (82% vs. 19%, p = 0.0001), thrombocytopenia (65% vs. 19%, p = 0.013), hypertriglyceridemia (87% vs. 42%, p = 0.037), and hyperferritinemia (93% vs. 37%, p = 0.011) were also more frequently observed in AP patients with MAS compared in AP patients without MAS. Fever and hyperferritinemia concomitantly were more frequent in the former group (86% vs. 12%, p = 0.0015). Higher and significant frequency of AP in cSLE compared to aSLE patients [12/362 (3.3%) vs. 20/1830 (1.1%), p = 0.003], with similar AP duration [22 (6-60) vs. 15 (4-90) days, p = 0.534]. MAS (85% vs. 30%, p = 0.003) and death by MAS complication (31% vs. 0%, p = 0.017) were significantly higher in children compared with aSLE.

CONCLUSIONS

This study provides novel data demonstrating that MAS occur in the majority of cSLE with AP with a higher mortality compared to aSLE. In addition, we identified in AP patients, a cluster of MAS clinical and laboratorial parameters more associated with this complication.

Clinical features and correct diagnosis of macrophage activation syndrome

Macrophage activation syndrome (MAS) is increasingly recognized among febrile hospitalized patients. Clinically, MAS resembles multiorgan dysfunction and shock. Laboratory features include hepatobiliary dysfunction, coagulopathy, pancytopenia, hyperferritinemia and markers of immune activation. Pathologically, hemophagocytosis is commonly seen but is only present in 60% of MAS patients. MAS, or secondary hemophagocytic lymphohistiocytosis (HLH), is triggered by infectious (e.g., herpes family viruses), rheumatologic (e.g., systemic lupus erythematosus [SLE]) and oncologic (e.g., T-cell leukemia) conditions. Formal HLH criteria, while specific, are frequently insensitive for MAS diagnosis. Thus, disease-specific (e.g., SLE) and generic MAS criteria have been published. Recently, novel criteria for MAS in children with systemic juvenile idiopathic arthritis (sJIA) were developed and are a key focus of this review.

Histiocytic glomerulopathy associated with macrophage activation syndrome

We present an interesting case of a 37-year old man with acute renal failure following a febrile illness. Laboratory results showed features of macrophage activation syndrome (MAS) with anemia, thrombocytopenia, hypofibrinogenemia and elevated ferritin levels. Renal biopsy was then done to determine the cause of renal failure and showed unique glomerular findings with massive histiocytic infiltration ('histiocytic glomerulopathy') and evidence of endothelial injury. Recognizing that the histiocytic infiltrate and endothelial injury is a part of MAS is important because early recognition and treatment is of utmost importance since the disease can be fatal.

Hemophagocytic lymphohistiocytosis: review of etiologies and management

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

Long-term follow-up of autologous stem cell transplantation for severe paediatric systemic lupus erythematosus

This study attempts to evaluate the outcome of autologous peripheral blood hematopoietic stem cell transplantation (auto-PBHSCT) in patients with severe paediatric systemic lupus erythematosus (SLE). Five patients (n = 2 females, n = 3 males) with severe or refractory paediatric SLE received autologous peripheral blood CD34+ cell transplants between July 2005 and February 2009. The patients ranged in age from 6 to 14 years, and the course of disease extended over a period from 5 to 90 months. All of the patients received conventional therapy for 3 to 87 months. After their discharge from the hospital, the patients continued to maintain their regular follow-up visits and basic quality of life. The patients exhibited decreased immune function after the auto-PBHSCT. The CD4+ and CD19+ cells were significantly reduced. Viremia occurred in four patients 2 months after the transplantation. All of the patients went into clinical remission in 3-6 months. The severity of encephalopathy, nephritis and organ damage declined in varying degrees. The disease recurred in patient 2 at 9 months and in patient 4 at 12 months after the transplantation. Because the disease was relatively mild, we were able to administer small doses of glucocorticoids that were sufficient to control the course of the disease. Macrophage activation syndrome occurred in patient 3 at 18 months after the transplantation. At the end of the follow-up period, three of the five patients were completely off their medications. Another two patients sustained small doses of glucocorticoids. The developmental levels of these patients were comparable to those of normal children at the end of the follow-up. The quality of life improved significantly. The auto-PBHSCT is effective for severe and refractory paediatric SLE. The incidence of lethal infection and other adverse reactions is low. Long-term remission can be achieved. A milder form of the disease may have recurred after the transplantation.

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

OBJECTIVE

To describe patient demographics, interventions, and outcomes in hospitalized children with macrophage activation syndrome (MAS) complicating systemic lupus erythematosus (SLE) or juvenile idiopathic arthritis (JIA).

METHODS

We performed a retrospective cohort study using data recorded in the Pediatric Health Information System (PHIS) database from October 1, 2006 to September 30, 2010. Participants had International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes for MAS and either SLE or JIA. The primary outcome was hospital mortality (for the index admission). Secondary outcomes included intensive care unit (ICU) admission, critical care interventions, and medication use.

RESULTS

A total of 121 children at 28 children's hospitals met the inclusion criteria, including 19 children with SLE and 102 children with JIA. The index admission mortality rate was 7% (8 of 121 patients). ICU admission (33%), mechanical ventilation (26%), and inotrope/vasopressor therapy (26%) were common. Compared to children with JIA, those with SLE had a similar mortality rate (6% versus 11%, respectively; exact P = 0.6). More patients with SLE than those with JIA received ICU care (63% versus 27%; P = 0.002), received mechanical ventilation (53% versus 21%; P = 0.003), and had cardiovascular dysfunction (47% versus 23% received inotrope/vasopressor therapy; P = 0.02). Children with SLE and those with JIA received cyclosporine at similar rates, but more children with SLE received cyclophosphamide and mycophenolate mofetil, and more children with JIA received interleukin-1 antagonists.

CONCLUSION

Organ system dysfunction is common in children with rheumatic diseases complicated by MAS, and more organ system support is required in children with underlying SLE than in children with JIA. Current treatment of pediatric MAS varies based on the underlying rheumatic disease.

MKP-1 regulates cytokine mRNA stability through selectively modulation subcellular translocation of AUF1

MAPK phosphatase-1 (MKP-1)/dual specificity protein phosphatase-1 (DUSP-1) is a negative regulator of the host inflammatory response to infection. However, the mechanisms underlying the regulation of cytokine expression by MKP-1, especially at the post-transcriptional level, have not been fully delineated. In the current study, MKP-1 specifically dephosphorylated activated MAPK responses and attenuated LPS-induced IL-6, IL-10, and TNF-α expression. In addition, MKP-1 was important in destabilizing cytokine mRNAs. In LPS-stimulated rat macrophages with overexpressed MKP-1, half-lives of IL-6, IL-10 and TNF-α mRNAs were significantly reduced compared to controls. Conversely, half-lives of IL-6, IL-10, and TNF-α mRNAs were significantly increased in bone marrow macrophages derived from MKP-1 knock out (KO) mice compared with macrophages derived from MKP-1 wild type (WT) mice. Furthermore, MKP-1 promoted translocation of RNA-binding protein (RNA-BP) ARE/poly-(U) binding degradation factor 1 (AUF1) from the nucleus to the cytoplasm in response to LPS stimulation as evidenced by Western blot and immunofluorescent staining. Knockdown AUF1 mRNA expression by AUF1 siRNA in MKP-1 WT bone marrow macrophages significantly delayed degradation of IL-6, IL-10 and TNF- α mRNAs compared with controls. Finally, AUF1 was immunoprecipitated with the RNA complex in cellular lysates derived from bone marrow macrophages of MKP-1 KO vs. WT mice, which had increased AUF1-bound target mRNAs, including IL-6, IL-10, and TNF-α in WT macrophages compared with MKP-1 KO macrophages. Thus, this work provides new mechanistic insight of MKP-1 signaling and regulation of cytokine mRNA stability through RNA binding proteins in response to inflammatory stimuli.

The homeobox transcription factor VentX controls human macrophage terminal differentiation and proinflammatory activation

Macrophages are critical players in both innate and adaptive immunity. While the exogenous signaling events leading to the terminal differentiation of macrophages from monocytes have been studied extensively, the underlying intracellular transcriptional mechanisms remain poorly understood. Here we report that the homeobox transcription factor VentX plays a pivotal role in human macrophage terminal differentiation and proinflammatory function. Our study showed that VentX expression was upregulated upon human primary monocyte-to-macrophage differentiation induced by cytokines such as M-CSF, GM-CSF, and IL-3. Moreover, ablation of VentX expression in primary monocytes profoundly impaired their differentiation to macrophages, and ectopic expression of VentX in a myeloid progenitor cell line triggered its differentiation with prominent macrophage features. Further analysis revealed that VentX was pivotal for the proinflammatory response of terminally differentiated macrophages. Mechanistically, VentX was found to control expression of proteins key to macrophage differentiation and activation, including M-CSF receptor. Importantly, preliminary analysis of gene expression in leukocytes from patients with autoimmune diseases revealed a strong correlation between levels of VentX and those of proinflammatory cytokines. Our results provide mechanistic insight into the crucial roles of VentX in macrophage differentiation and proinflammatory activation and suggest that dysregulation of VentX may play a role in the pathogenesis of autoimmune diseases.

Macrophage activation syndrome in children with systemic onset juvenile idiopathic arthritis: clinical experience from northwest India

The objective of this study is to describe the clinical and laboratory features of macrophage activation syndrome (MAS) in systemic onset juvenile idiopathic arthritis (SOJIA) at a tertiary care center in northwest India. Review of medical records of all children with SOJIA admitted during the period January 1995-December 2008 in Pediatric Allergy and Immunology Unit, Advanced Pediatrics Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, was done. Six patients (5 boys and 1 girl) with SOJIA and MAS were identified. Mean age at time of disease onset was 6.5 years. MAS was the presenting manifestation of SOJIA in 4 patients. Clinical manifestations included fever (6/6), clinical shock (6/6), encephalopathy (5/6), generalized lymphadenopathy (4/6), hepatosplenomegaly (3/6), jaundice and abdominal tenderness (3/6), cardiac involvement (3/6), and meningeal irritation (2/6). Laboratory findings at onset of MAS included decreasing total leukocyte and platelet counts, coagulopathy, elevated transaminases, hyponatremia, and lipid abnormalities. Hemophagocytosis was demonstrable in the bone marrow in 4 patients and in the lymph node in 1. For treatment, we used intravenous methylprednisolone (4/6), oral prednisolone (2/6), and intravenous immunoglobulin (2/6). Outcome was favorable in all patients except one who died of rapidly progressive disease. This paper describes the experience of JIA-related macrophage activation syndrome in a tertiary Indian center. We have shown that MAS can be the early presenting manifestation of evolving SOJIA. Early diagnosis and aggressive management can have a significant impact on the mortality associated with this syndrome. We stress on the role of glucocorticoids in the management of this condition and believe that glucocorticoids have a far more important role in the management of this condition than what has been previously reported.

Etanercept-induced lupus accompanied by hemophagocytic syndrome

Hemophagocytic syndrome (HPS) is a severe, potentially life-threatening disorder characterized by an excessive activation of macrophages, such as may occur in the setting of lupus. A 62-year-old Japanese woman treated with etanercept for rheumatoid arthritis developed persistent fever, cytopenia, coagulopathy, and hyperferritinemia. Simultaneously, lupus-like features including pleuritis, hypocomplementemia, and positive autoantibodies were observed. She was diagnosed with HPS related to etanercept-induced lupus, and underwent immunosuppressive therapy with successful recovery. To our knowledge, this is the first case of etanercept-induced lupus accompanied by HPS. This case suggests that HPS should be considered as a complication during TNF-α inhibitor therapy.

Acute pancreatitis in juvenile systemic lupus erythematosus: a manifestation of macrophage activation syndrome?

Acute pancreatitis (AP) is a rare and life-threatening manifestation of juvenile systemic lupus erythematosus (JSLE). The objective of this study was to evaluate the prevalence and clinical features of AP in our JSLE population. AP was defined according to the presence of abdominal pain or vomiting associated to an increase of pancreatic enzymes and/or pancreatic radiological abnormalities. Of note, in the last 26 years, 5367 patients were followed up at our Pediatric Rheumatology Unit and 263 (4.9%) of them had JSLE diagnosis (ACR criteria). AP was observed in 4.2% (11/263) of JSLE patients. The median of age of the JSLE patients at AP diagnosis was 12.4 years (8.8-17.9). All of them had lupus disease activity at AP onset. Three patients were receiving corticosteroids before AP diagnosis. Interestingly, 10/11 JSLE patients fulfilled preliminary guidelines for macrophage activation syndrome, three of them with macrophage hemophagocytosis in bone marrow aspirate and hyperferritinemia. The hallmark of this syndrome is excessive activation and proliferation of T lymphocytes and macrophages with massive hypersecretion of proinflammatory cytokines and clinically it is characterized by the occurrence of unexplained fever, cytopenia and hyperferritinemia. AP treatment was mainly based on intravenous methylprednisolone. Four JSLE patients with AP died and two developed diabetes mellitus. In conclusion, AP was a rare and severe manifestation in active pediatric lupus. The association between AP and macrophage activation syndrome suggests that the pancreas could be a target organ of this syndrome and that pancreatic enzyme evaluation should also be carried out in all patients.

6-mercaptopurine inhibits atherosclerosis in apolipoprotein e*3-leiden transgenic mice through atheroprotective actions on monocytes and macrophages

OBJECTIVE

6-Mercaptopurine (6-MP), the active metabolite of the immunosuppressive prodrug azathioprine, is commonly used in autoimmune diseases and transplant recipients, who are at high risk for cardiovascular disease. Here, we aimed to gain knowledge on the action of 6-MP in atherosclerosis, with a focus on monocytes and macrophages.

METHODS AND RESULTS

We demonstrate that 6-MP induces apoptosis of THP-1 monocytes, involving decreased expression of the intrinsic antiapoptotic factors B-cell CLL/Lymphoma-2 (Bcl-2) and Bcl2-like 1 (Bcl-x(L)). In addition, we show that 6-MP decreases expression of the monocyte adhesion molecules platelet endothelial adhesion molecule-1 (PECAM-1) and very late antigen-4 (VLA-4) and inhibits monocyte adhesion. Screening of a panel of cytokines relevant to atherosclerosis revealed that 6-MP robustly inhibits monocyte chemoattractant chemokine-1 (MCP-1) expression in macrophages stimulated with lipopolysaccharide (LPS). Finally, local delivery of 6-MP to the vessel wall, using a drug-eluting cuff, attenuates atherosclerosis in hypercholesterolemic apolipoprotein E*3-Leiden transgenic mice (P<0.05). In line with our in vitro data, this inhibition of atherosclerosis by 6-MP was accompanied with decreased lesion monocyte chemoattractant chemokine-1 levels, enhanced vascular apoptosis, and reduced macrophage content.

CONCLUSIONS

We report novel, previously unrecognized atheroprotective actions of 6-MP in cultured monocytes/macrophages and in a mouse model of atherosclerosis, providing further insight into the effect of the immunosuppressive drug azathioprine in atherosclerosis.

Macrophage activation syndrome in juvenile systemic lupus erythematosus: a multinational multicenter study of thirty-eight patients

OBJECTIVE

To describe the clinical and laboratory features of macrophage activation syndrome as a complication of juvenile systemic lupus erythematosus (SLE).

METHODS

Cases of juvenile SLE-associated macrophage activation syndrome were provided by investigators belonging to 3 pediatric rheumatology networks or were found in the literature. Patients who had evidence of macrophage hemophagocytosis on bone marrow aspiration were considered to have definite macrophage activation syndrome, and those who did not have such evidence were considered to have probable macrophage activation syndrome. Clinical and laboratory findings in patients with macrophage activation syndrome were contrasted with those of 2 control groups composed of patients with active juvenile SLE without macrophage activation syndrome. The ability of each feature to discriminate macrophage activation syndrome from active disease was evaluated by calculating sensitivity, specificity, and area under the receiver operating characteristic curve.

RESULTS

The study included 38 patients (20 with definite macrophage activation syndrome and 18 with probable macrophage activation syndrome). Patients with definite and probable macrophage activation syndrome were comparable with regard to all clinical and laboratory features of the syndrome, except for a greater frequency of lymphadenopathy, leukopenia, and thrombocytopenia in patients with definite macrophage activation syndrome. Overall, clinical features had better specificity than sensitivity, except for fever, which was highly sensitive but had low specificity. Among laboratory features, the best sensitivity and specificity was achieved using hyperferritinemia, followed by increased levels of lactate dehydrogenase, hypertriglyceridemia, and hypofibrinogenemia. Based on the results of statistical analysis, preliminary diagnostic guidelines for macrophage activation syndrome in juvenile SLE were developed.

CONCLUSION

Our findings indicate that the occurrence of unexplained fever and cytopenia, when associated with hyperferritinemia, in a patient with juvenile SLE should raise the suspicion of macrophage activation syndrome. We propose preliminary guidelines for this syndrome in juvenile SLE to facilitate timely diagnosis and correct classification of patients.

D-penicillamine-induced autoimmunity: relationship to macrophage activation

Idiosyncratic drug reactions represent a serious health problem, and they remain unpredictable largely due to our limited understanding of the mechanisms involved. Penicillamine-induced autoimmunity in Brown Norway (BN) rats represents one model of an idiosyncratic reaction, and this drug can also cause autoimmune reactions in humans. We previously demonstrated that penicillamine binds to aldehydes on the surface of macrophages. There is evidence that an imine bond formed by aldehyde groups on macrophages and amine groups on T cells is one type of interaction between these two cells that is involved in the induction of an immune response. We proposed that the binding of penicillamine with aldehyde groups on macrophages could lead to their activation and in some patients could lead to autoimmunity. In this study, the transcriptome profile of spleen macrophages 6 h after penicillamine treatment was used to detect effects of penicillamine on macrophages with a focus on 20 genes known to be macrophage activation biomarkers. One biological consequence of macrophage activation was investigated by determining mRNA levels for IL-15 and IL-1 beta which are crucial for NK cell activation, as well as levels of mRNA for selected cytokines in spleen NK cells. Up-regulation of the macrophage activating cytokines, IFN-gamma and GM-CSF, and down-regulation of IL-13 indicated activation of NK cells, which suggests a positive feedback loop between macrophages and NK cells. Furthermore, treatment of a murine macrophage cell line, RAW264.7, with penicillamine increased the production of TNF-alpha, IL-6, and IL-23, providing additional evidence that penicillamine activates macrophages. Hydralazine and isoniazid cause a lupus-like syndrome in humans and also bind to aldehyde groups. These drugs were also found to activate RAW264.7 macrophages. Together, these data support the hypothesis that drugs that bind irreversibly with aldehydes lead to macrophage activation, which in some patients can lead to an autoimmune syndrome.

Hemophagocytic syndrome as one of the main primary manifestations in acute systemic lupus erythematosus - case report and literature review

Hemophagocytic syndrome is an unusual but fatal disorder characterized by pancytopenia and activation of macrophages. We describe one case of acute systemic lupus erythematosus with an unusual presentation of hemophagocytic syndrome not related to infection. The patient presented with pancytopenia related to increasing hemophagocytic activity of histiocytes in the bone marrow. Concomitant class IV World Health Organization lupus nephritis, serositis, high titer of antinuclear factor and positive test for anti-DNA antibody fitted the diagnostic criteria of systemic lupus erythematosus. She also presented with alveolar hemorrhage and lupus myocarditis. She underwent immunosuppressive therapy with recovery from the hemophagocytic syndrome. Therefore, diagnosis of acute lupus hemophagocytic syndrome was made. The clinical presentation, laboratory diagnosis, and management of the patient are discussed and the literature was reviewed and presented, with emphasis on a possible distinct lupus subset, which includes a more aggressive systemic disease with heart involvement.

[Hemophagocytic syndrome in late-onset SLE patients]

We report two elderly male patients with hemophagocytic syndrome (HPS) associated with systemic lupus erythematosus (SLE). They were admitted to the hospital because of general malaise. At admission, they showed fever of unknown origin and hematological abnormalities without typical symptoms for SLE such as arthralgia or malar rash. Chest X-rays, computed tomography and cardiac sonogram demonstrated unilateral pleural and pericardial effusions. Bone marrow aspiration revealed hypocellular marrow with increased macrophages phagocytosing blood cells in the both cases. One patient had positive reactivity for direct Coombs's test and high level of platelet-associated antibody, whose symptoms were ameliorated only by 20 mg per day of prednisolone. The other patient, however, progressive worsened and died regardless of intensive treatment containing methyl-prednisolone pulse therapy. Late-onset lupus (LO-SLE) patients tend to have a more insidious onset of disease, and less frequently show typical symptoms of early-onset SLE such as malar rash. So it seems to be important that clinicians make a fast diagnosis and proper treatment for LO-SLE and associated HPS by careful observation for the latent symptoms and laboratory findings.