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.

Neutrophil activation biomarker pentraxin 3 for diagnosis and monitoring of macrophage activation syndrome occurrence in adult-onset Still's disease

Macrophage activation syndrome (MAS) is a potentially fatal consequence of adult-onset Still's disease (AOSD), driven by a cytokine storm. Efficient early diagnosis of AOSD-associated MAS requires a sensitive and specific biomarker. In this study, we demonstrated that pentraxin 3 (PTX3), an acute phase protein, was associated with AOSD disease activity and served as a biomarker for AOSD-MAS. PTX3 levels were significantly increased in AOSD patients compared to other autoimmune diseases and healthy controls. Plasma PTX3 levels showed positive correlations with inflammatory markers, the systemic score and the HScore. In active AOSD with MAS, PTX3 levels were higher compared to those in non-AOSD haemophagocytic lymphohistiocytosis (HLH) patients. Moreover, the PTX3's area under the curve value for distinguishing AOSD with MAS exceeded that of soluble interleukin-2 receptor, ferritin and C-reactive protein. Furthermore, plasma levels of PTX3 were associated with circulating NET-DNA levels. To fully understand the underlying mechanism of PTX3 prompting AOSD and AOSD-MAS progression, we discovered that neutrophils exhibited enhanced NET formation and mitogen-activated protein kinases (MAPK) pathway activation upon PTX3 stimulation. More importantly, PTX3-induced NET formation was effectively dampened by MAPK pathway inhibitors. These findings collectively revealed that PTX3 has a favorable correlation with disease activity and may serve as a potential biomarker to differentiate AOSD patients with MAS. Additionally, PTX3 induces NET release via the MAPK pathway, suggesting a pathogenic role in AOSD-MAS.

Immunopathology of and potential therapeutics for secondary hemophagocytic lymphohistiocytosis/macrophage activation syndrome: a translational perspective

Secondary hemophagocytic lymphohistiocytosis/macrophage activation syndrome (sHLH/MAS) is a life-threatening immune disorder triggered by rheumatic disease, infections, malignancies, or medications. Characterized by the presence of hemophagocytic macrophages and a fulminant cytokine storm, sHLH/MAS leads to hyperferritinemia and multiorgan failure and rapidly progresses to death. The high mortality rate and the lack of specific treatments necessitate the development of a new drug. However, the complex and largely unknown immunopathologic mechanisms of sHLH/MAS, which involve dysfunction of various immune cells, diverse etiologies, and different clinical contexts make this effort challenging. This review introduces the terminology, diagnosis, and clinical features of sHLH/MAS. From a translational perspective, this review focuses on the immunopathological mechanisms linked to various etiologies, emphasizing potential drug targets, including key molecules and signaling pathways. We also discuss immunomodulatory biologics, existing drugs under clinical evaluation, and novel therapies in clinical trials. This systematic review aims to provide insights and highlight opportunities for the development of novel sHLH/MAS therapeutics.

Disease Course, Treatments, and Outcomes of Children With Systemic Juvenile Idiopathic Arthritis-Associated Lung Disease

OBJECTIVE

Systemic juvenile idiopathic arthritis-associated lung disease (SJIA-LD) is a life-threatening disease complication. Key questions remain regarding clinical course and optimal treatment approaches. The objectives of the study were to detail management strategies after SJIA-LD detection, characterize overall disease courses, and measure long-term outcomes.

METHODS

This was a prospective cohort study. Clinical data were abstracted from the electronic medical record, including current clinical status and changes since diagnosis. Serum biomarkers were determined and correlated with presence of LD.

RESULTS

We enrolled 41 patients with SJIA-LD, 85% with at least one episode of macrophage activation syndrome and 41% with adverse reactions to a biologic. Although 93% of patients were alive at last follow-up (median 2.9 years), 37% progressed to requiring chronic oxygen or other ventilator support, and 65% of patients had abnormal overnight oximetry studies, which changed over time. Eighty-four percent of patients carried the HLA-DRB1*15 haplotype, significantly more than patients without LD. Patients with SJIA-LD also showed markedly elevated serum interleukin-18 (IL-18), variable C-X-C motif chemokine ligand 9 (CXCL9), and significantly elevated matrix metalloproteinase 7. Treatment strategies showed variable use of anti-IL-1/6 biologics and addition of other immunomodulatory treatments and lung-directed therapies. We found a broad range of current clinical status independent of time from diagnosis or continued biologic treatment. Multidomain measures of change showed imaging features were the least likely to improve with time.

CONCLUSION

Patients with SJIA-LD had highly varied courses, with lower mortality than previously reported but frequent hypoxia and requirement for respiratory support. Treatment strategies were highly varied, highlighting an urgent need for focused clinical trials.

Clinical features of anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis with macrophage activation syndrome

OBJECTIVES

This study aimed to describe the clinical features of patients with anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody-positive dermatomyositis (DM) who had macrophage activation syndrome (MAS).

METHODS

We retrospectively examined 44 patients with anti-MDA5-positive DM and compared the clinical features between patients with MAS (n = 11) and those without (n=33). Patients without MAS were selected randomly in the same year as those with MAS at a ratio of 3:1. Among patients with MAS, we compared the features between non-survivors and survivors. We used Fisher's exact test, Student's t test, the Mann-Whitney U test and the log-rank test for statistical analysis.

RESULTS

Patients complicated with MAS had a significantly higher incidence of infection, heliotrope sign, Gottron's papule, V-neck sign, and higher serum levels of ferritin, aspartate aminotransferase (AST), lactic dehydrogenase (LDH), and creatine kinase (CK) than those without MAS (p<0.05). Among the 11 patients with MAS, 4 (36.4%) died after intensive treatment. Deceased patients were older, given more combination therapy with tofacitinib (TOF) and had a higher incidence of rapid progressive interstitial lung disease, infection, heart failure and renal impairment than those who survived (p<0.05).

CONCLUSIONS

Among anti-MDA5-positive DM, Infection, DM typical rashes, and higher serum levels of ferritin, AST, LDH, and CK were more common in patients complicated with MAS. The mortality of patients with MAS was high, particularly among patients who were older, given more combination therapy with TOF, and had RP-ILD, infection, heart failure and renal impairment.

Macrophage activation syndrome with acute hepatitis in a patient with adult-onset immunodeficiency with anti-interferon gamma antibodies: a case report

BACKGROUND

Macrophage activation syndrome is a rare disorder leading to unregulated immune activity manifesting with nonspecific constitutional symptoms, laboratory abnormalities, and multiorgan involvement. We report the case of a patient who presented with acute hepatitis secondary to macrophage activation syndrome diagnosed by liver biopsy and successfully treated with intravenous immune globulin, anakinra, and rituximab.

CASE PRESENTATION

A 42-year-old Laotian woman with adult-onset immunodeficiency with anti-interferon gamma antibodies presented with a fever, headache, generalized myalgia, dark urine, and reduced appetite in the setting of family members at home with similar symptoms. Her laboratory workup was notable for evidence of acute hepatitis without acute liver failure. After an unrevealing comprehensive infectious and noninvasive rheumatologic workup was completed, a liver biopsy was performed ultimately revealing the diagnosis of macrophage activation syndrome. She was successfully treated with intravenous immune globulin, anakinra, and rituximab.

CONCLUSION

This case highlights the importance of maintaining macrophage activation syndrome on the differential of a patient with acute hepatitis of unknown etiology in the correct clinical context and the value of a liver biopsy in making a diagnosis when noninvasive testing is unrevealing.

A rare case of coronary artery complication in a child with systemic juvenile idiopathic arthritis and macrophage activation syndrome: case report and literature review

A rare case of coronary artery involvement in a child with Systemic Juvenile Idiopathic Arthritis (sJIA) complicated by Macrophage Activation Syndrome (MAS) is reported. The patient initially received an inaccurate diagnosis of Kawasaki Disease, sepsis, and mycoplasma infection and showed no improvement after Intravenous Immune Globulin (IVIG) treatment. Upon admission, symptoms included diffuse red rash, swelling of the limbs, lymph node enlargement, and hepatosplenomegaly. Post investigations, a diagnosis of sJIA and MAS was confirmed, and treatment involved a combination of hormones (methylprednisolone) and immunosuppressive drugs (methotrexate). The revealed widened coronary artery diameter was managed with a disease-specific treatment plan and prophylactic plus low-dose aspirin anti-coagulation therapy. Under this management, MAS was well controlled, and follow-ups showed normalization of the child's coronary artery structure and function. This case and the associated literature review underscore the importance of early recognition, diagnosis, treatment, and long-term monitoring for children presenting with sJIA and MAS complicated by coronary artery involvement.

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.

Marginal Zone Lymphoma Manifesting as Macrophage Activation Syndrome: A Case Report

Macrophage activation syndrome (MAS) is a form of secondary hemophagocytic lymphohistiocytosis (HLH) when it occurs in the context of rheumatologic disorders. HLH is a rare and potentially life-threatening syndrome characterized by excessive immune system activation. It is mainly seen in children and can be genetic based or related to infections, malignancies, rheumatologic disorders, or immunodeficiency syndromes. MAS can present with nonspecific symptoms, leading to a delay in diagnosis. This report describes a case of a 64-year-old female with marginal zone lymphoma and systemic lupus erythematosus who presented with a purpuric rash and acute kidney injury. She underwent a kidney biopsy and was diagnosed with MAS. This case highlights the importance of promptly recognizing MAS's symptoms and signs, allowing timely diagnosis and early therapeutic intervention. This potentially fatal condition tends to respond well to rapid treatment initiation with corticosteroids and to address the underlying condition.

Clinical features of macrophage activation syndrome in adult dermatomyositis: A single-center retrospective case-control study

BACKGROUND

Little is known about the features of macrophage activation syndrome (MAS) in dermatomyositis, especially the association between rapidly progressive interstitial lung disease (RP-ILD) and MAS.

OBJECTIVE

To determine the characteristics of MAS in patients with dermatomyositis and their association with RP-ILD.

METHODS

This was a retrospective cohort study of 201 dermatomyositis patients at the First Affiliated Hospital of Zhejiang University over a 10-year period.

RESULTS

A total of 22 (10.9%) patients were diagnosed with MAS. The rate of RP-ILD was significantly higher in patients with MAS than in those without MAS (81.8% vs. 17.4%, respectively, p < .001). Multivariate analysis indicated that RP-ILD (p = .019), ferritin level > 1685 ng/mL (p = .007) and hemoglobin < 100 g/L (p = .001) were independent risk factors for MAS. Furthermore, RP-ILD patients with MAS presented more cardiac injury (50.0% vs. 13.3%, respectively, p < .009), central nervous system dysfunction (42.8% vs. 3.4%, respectively, p < .001) and hemorrhage (38.9% vs. 3.3%, respectively, p = .003) than RP-ILD patients without MAS. The 90-day cumulative survival rate for patients with MAS was significantly lower than for those without MAS (18.2% vs. 82.1%, respectively, p < .001).

CONCLUSION

MAS was a common and fatal complication of dermatomyositis in our cohort. MAS is closely related to RP-ILD in patients with dermatomyositis. When RP-ILD is present in dermatomyositis patients with abnormal laboratory findings, such as cytopenia and hyperferritinemia, the presence of MAS should be considered.

Immunohistochemical expression of perforin in adult systemic lupus erythematosus associated macrophage activation syndrome: Clinicohematological correlation and literature review

OBJECTIVE

To study the bone marrow (BM) immunohistomorphological characteristics in adult systemic lupus erythematosus (SLE) associated macrophage activation syndrome (SLE-MAS).

MATERIALS AND METHODS

Immunohistochemical (IHC) expression of CD3, CD8, perforin (PFN), and CD163 was studied on BM trephine biopsies from 30 cytopenic adult SLE cases (male: female = 1:5, age; 24 years, range; 19-32) and compared them with ten age matched controls. Clinicopathological parameters were compared among the cases likely (L) or unlikely (U) to have MAS using probability scoring criteria. The best cut off laboratory parameters to discriminate between the two were obtained through receiver operator curve (ROC) analysis.

RESULTS

MAS occurred in 12/30 (40%) cases and was more commonly associated with prior immunosuppressive therapy (p = .07), ≥ 3 system involvement (p = .09), lower fibrinogen (p < .01), increased triglyceride (p = .002), increased BM hemophagocytosis (p = .002), and higher MAS score [185 (176-203) vs. 105 (77-119), p < .01] than MAS-U subgroup. Although PFN+CD8+ T lymphocytes significantly decreased among cases than controls (p < .05), it was comparable between MAS-L and MAS-U subgroups. Fibrinogen (< 2.4 g/L, AUC; 0.93, p < .01), hemophagocytosis score (> 1.5, AUC; 0.71, p = .03), and an MAS probability score of ≥ 164 (AUC; 1, p < .01) discriminated MAS from those without MAS.

CONCLUSION

We noted a decrease in perforin mediated CD8 + T cell cytotoxicity in SLE. Immunohistochemical demonstration of the same along with histiocytic hemophagocytosis on BM biopsy may be useful adjunct in early diagnosis and management of MAS in SLE.

[Systemic lupus erythematosus associated macrophage activation syndrome with neuropsychiatric symptoms: A report of 2 cases]

Systemic lupus erythematosus (SLE) associated macrophage activation syndrome (MAS) is clinically severe, with a high mortality rate and rare neuropsychiatric symptoms. In the course of diagnosis and treatment, it is necessary to actively determine whether the neuropsychiatric symptoms in patients are caused by neuropsychiatric systemic lupus erythematosus (NPSLE) or macrophage activation syndrome. This paper retrospectively analyzed the clinical data of 2 cases of SLE associated MAS with neuropsychiatric lesions, Case 1: A 30-year-old female had obvious alopecia in 2019, accompanied by emaciation, fatigue and dry mouth. In March 2021, she felt weak legs and fell down, followed by fever and chills without obvious causes. After completing relevant examinations, she was diagnosed with SLE and given symptomatic treatments such as hormones and anti-infection, but the patient still had fever. The relevant examinations showed moderate anemia, elevated ferritin, elevated triglycerides, decreased NK cell activity, and a perforin positivity rate of 4.27%, which led to the diagnosis of "pre-hemophagocytic syndrome (HPS)". In May 2021, the patient showed mental trance and babble, and was diagnosed with "SLE-associated MAS"after completing relevant examinations. After treatment with methylprednisolone, anti-infection and psychotropic drugs, the patient's temperature was normal and mental symptoms improved. Case 2: A 30-year-old female patient developed butterfly erythema on both sides of the nose on her face and several erythema on her neck in June 2019, accompanied by alopecia, oral ulcers, and fever. She was diagnosed with "SLE" after completing relevant examinations, and her condition was relieved after treatment with methylprednisolone and human immunoglobulin. In October 2019, the patient showed apathy, no lethargy, and fever again, accompanied by dizziness and vomiting. The relevant examination indicated moderate anemia, decreased NK cell activity, elevated triglycerides, and elevated ferritin. The patient was considered to be diagnosed with "SLE, NPSLE, and SLE-associated MAS". After treatment with hormones, human immunoglobulin, anti-infection, rituximab (Mabthera), the patient's condition improved and was discharged from the hospital. After discharge, the patient regularly took methylprednisolone tablets (Medrol), and her psychiatric symptoms were still intermittent. In November 2019, she developed symptoms of fever, mania, and delirium, and later turned to an apathetic state, and was given methylprednisolone intravenous drip and olanzapine tablets (Zyprexa) orally. After the mental symptoms improved, she was treated with rituximab (Mabthera). Later, due to repeated infections, she was replaced with Belizumab (Benlysta), and she was recovered from her psychiatric anomalies in March 2021. Through the analysis of clinical symptoms, imaging examination, laboratory examination, treatment course and effect, it is speculated that the neuropsychiatric symptoms of case 1 are more likely to be caused by MAS, and that of case 2 is more likely to be caused by SLE. At present, there is no direct laboratory basis for the identification of the two neuropsychiatric symptoms. The etiology of neuropsychiatric symptoms can be determined by clinical manifestations, imaging manifestations, cerebrospinal fluid detection, and the patient's response to treatment. Early diagnosis is of great significance for guiding clinical treatment, monitoring the condition and judging the prognosis. The good prognosis of the two cases in this paper is closely related to the early diagnosis, treatment and intervention of the disease.

Macrophage activation syndrome triggered by methotrexate-related lymphoproliferative disease in a patient with rheumatoid arthritis

A 56-year-old woman was treated for rheumatoid arthritis for 17 years with methotrexate (MTX). Night sweats, fever and weight loss made her visit our hospital. Although levofloxacin failed to resolve her fever, she was suspected of having sepsis because of pancytopenia, elevated procalcitonin and a nodular lesion in the lung. After urgent hospitalization, she was diagnosed finally with the methotrexate-related lymphoproliferative disorder (MTX-LPD) associated with macrophage activation syndrome (MAS). Her general condition was improved with MTX withdrawal and 5-day high-dose glucocorticoid administration. Thus, even when the patient was critically ill with MAS, no cytotoxic agents were required to control MTX-LPD.

Clinical Course and Cytokine Profile of Systemic Juvenile Idiopathic Arthritis in a Patient with Trisomy 21

Trisomy 21 (Down syndrome) is sometimes complicated by congenital heart disease; however, comorbid type I diabetes mellitus and diseases involving autoantibodies, such as Hashimoto disease and Graves disease, are not uncommon. Autoinflammatory diseases such as Kawasaki disease and systemic juvenile idiopathic arthritis are rare. We report a rare case of trisomy 21 with systemic juvenile idiopathic arthritis that responded well to the initial course of methylprednisolone pulse therapy but flared up and was complicated by macrophage activation syndrome (MAS). Subsequent methylprednisolone pulse therapy and cyclosporine resolved this condition. Cytokines were analyzed at several time points during the clinical course and revealed that interleukin-18, interleukin-6, and chemokine ligand 9 levels were elevated at MAS onset in the present patient, even though clinical symptoms had abated. Thus, early analysis of cytokine profiles should be performed to assess MAS risk and determine treatment intensity, even in T21 patients.

Differences and similarities in cytokine profiles of macrophage activation syndrome in systemic lupus erythematosus and adult-onset Still's disease

To clarify the differences and similarities in the cytokine profiles of macrophage activating syndrome (MAS) between systemic lupus erythematosus (SLE) and adult-onset Still's disease (AOSD). The study participants included 9 patients with MAS-SLE, 22 with non-MAS-SLE, 9 with MAS-AOSD, and 13 with non-MAS-AOSD. Serum cytokine levels were measured using a multiplex bead assay. Cytokine levels were compared between patients with SLE and AOSD with/without MAS. Moreover, cytokine patterns were examined using principal component analysis (PCA) and cluster analysis. IL-6, IL-8, IL-18, and TNF-α levels were elevated in patients with SLE and AOSD. IFN-α levels were elevated in SLE, whereas IL-1β and IL-18 levels were elevated in AOSD. In SLE, IFN-α and IL-10 levels were higher in MAS than in non-MAS and controls. PCA revealed distinctive cytokine patterns in SLE and AOSD, SLE with IFN-α and IP-10, AOSD with IL-1β, IL-6, and IL-18, and enhanced cytokine production in MAS. PCA and cluster analysis showed no differences in cytokine patterns between the MAS and non-MAS groups. However, serum ferritin levels were correlated with IFN-α levels in SLE. Cytokine profiles differed between SLE and AOSD but not between MAS and non-MAS. MAS is induced by the enhancement of underlying cytokine abnormalities rather than by MAS-specific cytokine profiles. Type I IFN may be involved in MAS development in patients with SLE.

Clinical and laboratory features associated with macrophage activation syndrome in Still's disease: data from the international AIDA Network Still's Disease Registry

To characterize clinical and laboratory signs of patients with Still's disease experiencing macrophage activation syndrome (MAS) and identify factors associated with MAS development. Patients with Still's disease classified according to internationally accepted criteria were enrolled in the AutoInflammatory Disease Alliance (AIDA) Still's Disease Registry. Clinical and laboratory features observed during the inflammatory attack complicated by MAS were included in univariate and multivariate logistic regression analysis to identify factors associated to MAS development. A total of 414 patients with Still's disease were included; 39 (9.4%) of them developed MAS during clinical history. At univariate analyses, the following variables were significantly associated with MAS: classification of arthritis based on the number of joints involved (p = 0.003), liver involvement (p = 0.04), hepatomegaly (p = 0.02), hepatic failure (p = 0.01), axillary lymphadenopathy (p = 0.04), pneumonia (p = 0.03), acute respiratory distress syndrome (p < 0.001), platelet abnormalities (p < 0.001), high serum ferritin levels (p = 0.009), abnormal liver function tests (p = 0.009), hypoalbuminemia (p = 0.002), increased LDH (p = 0.001), and LDH serum levels (p < 0.001). At multivariate analysis, hepatomegaly (OR 8.7, 95% CI 1.9-52.6, p = 0.007) and monoarthritis (OR 15.8, 95% CI 2.9-97.1, p = 0.001), were directly associated with MAS, while the decade of life at Still's disease onset (OR 0.6, 95% CI 0.4-0.9, p = 0.045), a normal platelet count (OR 0.1, 95% CI 0.01-0.8, p = 0.034) or thrombocytosis (OR 0.01, 95% CI 0.0-0.2, p = 0.008) resulted to be protective. Clinical and laboratory factors associated with MAS development have been identified in a large cohort of patients based on real-life data.

Adult-onset Still's disease complicated by macrophage activation syndrome during pregnancy: a case-based review

Adult-onset Still's disease is a rare, systemic inflammatory rheumatic disease characterized by recurrent fevers, arthritis, and an evanescent rash. One of the most serious hematologic derangements that can be seen with adult-onset Still's disease is macrophage activation syndrome. Macrophage activation syndrome is characterized by activation of lymphocytes, resulting in a cytokine storm and hemophagocytosis in the bone marrow, along with multi-organ failure. Adult-onset Still's disease with macrophage activation syndrome first presenting during pregnancy is exceptionally rare; here, we report two unique cases of such a presentation and review the pertinent literature. Both of our cases presented critically ill with end-organ failure, and responded to immunosuppression; fetal demise was present in one and an emergency caesarean section with a viable fetus was performed in the other patient. Maternal outcomes were favorable in both cases and both patients did well long-term with systemic therapy. Systemic immunosuppression, particularly anti-IL1 therapy, may be considered as treatment for this rare and life-threatening condition when presenting during pregnancy.

Performance of interferon-gamma levels may lead to earlier diagnosing macrophage activation syndrome complicating systemic juvenile idiopathic arthritis

Macrophage activation syndrome (MAS) is a severe, potentially fatal complication of rheumatic diseases, predominantly in systemic juvenile idiopathic arthritis (SJIA), and is considered as an autoinflammatory disease. Specific cytokine profiles could play a pivotal role in this inflammatory response. Gram-negative bacteremia, bacterial pneumonia, Kawasaki disease, and active SJIA exhibited similar cytokine profiles with elevated interleukin-6 (IL-6) and/or IL-10, further suggesting a correlation between them. Only when JIA is complicated by MAS can increased interferon-γ (IFN-γ) levels be observed. Therefore, increased serum IFN-γ levels could contribute to early diagnosing MAS in patients with SJIA in combination with other variables such as serum ferritin. A prospective multi-center study will be performed to further confirm the role of IFN-γ in the early recognition of MAS in SJIA.

Anakinra and hepatotoxicity in pediatric rheumatology: a case series

BACKGROUND

Anakinra is a recombinant interleukin-1 (IL-1) receptor antagonist used in systemic juvenile idiopathic arthritis (sJIA), refractory Kawasaki disease (KD) and cryopyrin-associated autoinflammatory syndrome (CAPS). Anakinra associated hepatotoxicity, while rare, has been described in several cases in daily practice. ​In this case series the authors describe three pediatric patients with this side effect in the setting of severe macrophage activation syndrome (MAS) in KD and sJIA.

CASE PRESENTATION

The first patient was a 12-year-old boy who presented with fever, maculo-papular exanthema and polyarthralgia. Tonsillitis, distal limb induration and tender cervical lymph nodes were observed. Erythrocyte-sedimentation rate (ESR), C-reactive protein (CRP), ferritin (11,975 ng/mL), D-dimers (5,98 mg/L FEU) and soluble CD25 (3645 pg/mL) levels were elevated. Exclusion of sepsis / toxic shock syndrome warranted introduction of IV methylprednisolone and immunoglobulin (IG IV), with partial response. A MAS secondary to KD was assumed, and anakinra 2 mg/kg/day was introduced. Twenty days later he developed new-onset nausea and severe cyto-cholestasis, normalizing after 2 months of drug discontinuation. Posterior onset of polyarthritis and evanescent lead to a final diagnosis of sJIA. The second patient was a 2-year-old boy with a 10-day history of fevers, generalized rash, hepatosplenomegaly and strawberry tongue. Leucocytosis with neutrophilia and elevated CRP were observed. Initial treatment with IVIG in the setting of incomplete KD was ineffective. Mild anaemia, leukopenia and very high serum ferritin (maximum 26,128 ng/mL) ensued. Presumptive sJIA associated MAS was treated with IV methylprednisolone and anakinra 2 mg/kg/day, with prompt response. Four weeks later transaminitis was detected, and temporary anakinra suspension led to normalisation of laboratorial values. The third case related to a 4-year-old boy presenting with fever, maculopapular rash and cervical lymphadenopathy. CRP and ESR were elevated, and KD was diagnosed. IVIG and methylprednisolone were initiated with clinical worsening, warranting for anakinra introduction at 2 mg/kg/day. After three weeks, liver enzymes progressively elevated, resolving on 2 weeks of anakinra discontinuation.

CONCLUSIONS

To the best of our knowledge, this is the first case series describing anakinra associated hepatotoxicity in pediatric patients with rheumatic diseases other than sJIA, bringing additional insight to therapeutic monitoring in patients undergoing this treatment.

Hemophagocytic Lymphohistiocytosis With Elevated Cytokines Related to Macrophage Activation After Liver Transplantation for Autoimmune Hepatitis: A Case Report

Hemophagocytic lymphohistiocytosis (HLH) is a rare but lethal complication of liver transplantation (LT). HLH is characterized by pathologic macrophage activation with hypercytokinemia, excessive inflammation, and tissue destruction, resulting in progressive organ dysfunction. HLH is also known as macrophage activation syndrome (MAS) when complicated by rheumatic or autoinflammatory diseases. Measuring several serum cytokines could be helpful in diagnosing HLH and MAS. Cytokines related to macrophage activation: neopterin, interleukin-18 (IL-18), and soluble tumor necrosis factor receptors (sTNF-R) I and II have not been assessed in patients with HLH complicated by LT. In this case, these cytokines were evaluated in the perioperative period of LT. The patient was a 24-year-old woman who underwent living-donor LT for acute worsening of autoimmune hepatitis. On postoperative day 12, the patient was diagnosed with HLH on the basis of the criteria. Plasma exchange, steroid pulse therapy, intravenous immunoglobulin and granulocyte-colony stimulating factor effectively inhibited progression to lethal HLH. When HLH occurred after LT, cytokine analysis showed that neopterin, IL-18, sTNFR-I, and II were elevated: cytokine storm. Of note, cytokine analysis on hospital admission also revealed elevated cytokine levels. Particularly, IL-18 levels were markedly elevated, suggesting that activation of the innate immune system was involved. These results revealed that a cytokine storm and macrophage activation developed before LT. Based on these findings, cytokine analysis related to macrophage activation may be useful for diagnosing and predicting HLH and MAS in patients with LT.

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.

Macrophage activation syndrome in juvenile dermatomyositis: a case report and a comprehensive review of the literature

BACKGROUND

Macrophage activation syndrome (MAS) is a severe and life-threatening syndrome associated with autoimmune diseases. The coexistence of MAS and juvenile dermatomyositis (JDM) is not well reported. This report describes a case of JDM with MAS and summarizes the clinical characteristics and prognosis of MAS in patients with JDM.

CASE PRESENTATION

The patient was a 15-year-old female with JDM, presenting with heliotrope rash, muscle weakness, increased muscle enzyme, anti-nuclear matrix protein 2 (NXP2) antibody, and muscle biopsy consistent with JDM. The patient developed fever, cytopenia, and hyperferritinemia three months after the first manifestations. Hemophagocytosis was found in the bone marrow. The final diagnosis was JDM combined with MAS. Despite intensive treatment, the patient died of MAS. By reviewing the literature, we found 17 similar cases. Together with the present case, 18 patients were identified, the median age of disease onset was 13.5 years, and male to female ratio was 1.25: 1. Nine out of 16 (56.3%) patients were complicated with interstitial lung disease (ILD). The median time interval between JDM onset and MAS diagnosis was 9 weeks. At the onset of MAS, all (100%) patients had elevated levels of ferritin and serum liver enzymes. Among 18 patients, 14 (77.8%) had fever, 14/17 (82.4%) had cytopenia, 11/11 (100%) had hepatosplenomegaly, and 13/14 (92.9%) had hemophagocytosis. Five (27.8%) patients showed central nervous system (CNS) involvement. The mortality of MAS rate of in patients with JDM was 16.7%, despite various treatment methods.

CONCLUSION

. The coexistence of JDM and MAS is underestimated with increased mortality. Hepatosplenomegaly and increased serum levels of ferritin in patients with JDM should raise clinical suspicion for MAS.

Clinical significance of serum cytokine profiles for differentiating between Kawasaki disease and its mimickers

OBJECTIVES

To investigate the clinical significance of serum cytokine profiles for differentiating between Kawasaki disease (KD) and its mimickers.

METHODS

Patients with KD, including complete KD, KD shock syndrome (KDSS), and KD with macrophage activation syndrome (KD-MAS), and its mimickers, including multisystem inflammatory syndrome in children, toxic shock syndrome, and Yersinia pseudotuberculosis infection, were enrolled. Serum levels of interleukin (IL)-6, soluble tumor necrosis factor receptor type II (sTNF-RII), IL-10, IL-18, and chemokine (C-X-C motif) ligand 9 (CXCL9) were measured using enzyme-linked immunosorbent assay and compared them with clinical manifestations.

RESULTS

Serum IL-6, sTNF-RII, and IL-10 levels were significantly elevated in patients with KDSS. Serum IL-18 levels were substantially elevated in patients with KD-MAS. Patients with KD-MAS and KD mimickers had significantly elevated serum CXCL9 levels compared with those with complete KD. Area under the receiver operating characteristic curve analysis showed that serum IL-6 was the most useful for differentiating KDSS from the others, IL-18 and CXCL9 for KD-MAS from complete KD, and CXCL9 for KD mimickers from complete KD and KD-MAS.

CONCLUSION

Serum cytokine profiles may be useful for differentiating between KD and its mimickers.

Adult-onset Still's disease and fever of unknown origin in India

Despite an essential differential diagnosis for fever of unknown origin (FUO) in young adults, adult-onset Still's disease (AOSD) is infrequently considered and remained underdiagnosed in low-middle-income countries. The present study analyzed the clinical, serological, radiological, and pathological characteristics of AOSD presented as FUO in India. A hospital-based retrospective study of patients aged > 13 years admitted with FUO and later diagnosed with AOSD in Postgraduate Institute of Medical Education and Research, Chandigarh (India), was conducted between January 2014 and December 2020. Petersdorf and Beeson's criteria were used to define FUO. The diagnosis of AOSD was made based on Yamaguchi's criteria. Twenty-seven patients (median age 26 years, 14 females) were enrolled. All presented with intermittent fever with a median duration of 10 weeks. The typical features of AOSD at admission were arthralgia (n = 24), hepatosplenomegaly (n = 21), spiking fever ≥ 39 °C (n = 19), lymphadenopathy (n = 18), typical rash (n = 17), and sore throat (n = 11). Leukocytosis (n = 25) and neutrophilia (n = 19) were frequent. Hyperferritinemia was universal (range, 700-145,003 ng/ml; ≥ 2000, n = 23). At admission, AOSD was suspected in only nine FUO cases, while tuberculosis (n = 16), undifferentiated connective tissue disorder (n = 14), and lymphoproliferative disorder (n = 11) were common diagnostic possibilities. Crispin et al. clinical scale detected AOSD in only 15 (55.5%) FUO patients. Whole-body imaging (n = 27), including fluorodeoxyglucose positron emission tomography (n = 12), demonstrated reticuloendothelial organ-system involvement and serositis. Seventeen (63%) patients had macrophage activation syndrome at the time of AOSD diagnosis. AOSD FUO presents with typical but nonspecific features; thus, early differentiation from common causes (e.g., tuberculosis, lymphoma) is difficult. Macrophage activation syndrome is common in AOSD with FUO presentation.

Efficacy and safety of emapalumab in macrophage activation syndrome

OBJECTIVES

Macrophage activation syndrome (MAS) is a severe, life-threatening complication of systemic juvenile idiopathic arthritis (sJIA) and adult-onset Still's disease (AOSD). The objective of this study was to confirm the adequacy of an emapalumab dosing regimen in relation to interferon-γ (IFNγ) activity by assessing efficacy and safety. The efficacy outcome was MAS remission by week 8, based on clinical and laboratory criteria.

METHODS

We studied emapalumab, a human anti-IFNγ antibody, administered with background glucocorticoids, in a prospective single-arm trial involving patients who had MAS secondary to sJIA or AOSD and had previously failed high-dose glucocorticoids, with or without anakinra and/or ciclosporin. The study foresaw 4-week treatment that could be shortened or prolonged based on investigator's assessment of response. Patients entered a long-term (12 months) follow-up study.

RESULTS

Fourteen patients received emapalumab. All patients completed the trial, entered the long-term follow-up and were alive at the end of follow-up. The investigated dosing regimen, based on an initial loading dose followed by maintenance doses, was appropriate, as shown by rapid neutralisation of IFNγ activity, demonstrated by a prompt decrease in serum C-X-C motif chemokine ligand 9 (CXCL9) levels. By week 8, MAS remission was achieved in 13 of the 14 patients at a median time of 25 days. Viral infections and positive viral tests were observed.

CONCLUSIONS

Neutralisation of IFNγ with emapalumab was efficacious in inducing remission of MAS secondary to sJIA or AOSD in patients who had failed high-dose glucocorticoids. Screening for viral infections should be performed, particularly for cytomegalovirus.

TRIAL REGISTRATION NUMBER

NCT02069899 and NCT03311854.

Variations in Macrophage Activation Syndrome-associated Cardiac Diseases: A Report on Two Cases

Macrophage activation syndrome (MAS), a secondary hemophagocytic lymphohistiocytosis characterized by an excessive systemic inflammatory response, is a life-threatening and rare disease. Cardiovascular damage is a common and severe complication of the disease, however, it is easily ignored and not well studied. Herein, we report two cases of patients with MAS-associated heart damage and review the clinical characteristics, mechanism, and treatment. Case 1 along with systemic lupus erythematosus and Kikuchi necrotizing lymphadenitis occurred in fatal acute heart failure, and case 2 complicated adult-onset Still's Disease began with atrial fibrillation and had some improvement with the treatment of high dose corticosteroids. MAS-associated heart damage is a critical issue in clinical settings, and the etiology and mechanisms of MAS-associated cardiovascular diseases are likely multifactorial. The manifestations were various and high levels of the cytokines and cardiac damage may contribute to poor prognosis. Therefore, early intensive immunosuppressive therapy probably improves the treatment outcome.

Improvement of Refractory Systemic Juvenile Idiopathic Arthritis-Associated Lung Disease with Single-Agent Blockade of IL-1β and IL-18

Systemic juvenile idiopathic arthritis associated with interstitial lung disease (SJIA-LD) represents a highly morbid subset of SJIA for which effective therapies are lacking. We report the case of a patient with refractory SJIA-LD who underwent treatment with MAS-825, an investigational bispecific monoclonal antibody targeting IL-1β and IL-18. MAS-825 treatment was associated with a marked reduction in total IL-18 and free IL-18 in both serum and bronchoalveolar lavage fluid (BAL). Baseline oxygen saturation, exercise tolerance, and quality of life metrics improved after treatment with MAS-825, while pulmonary function testing remained stable. Following treatment, the BAL showed no evidence of pulmonary alveolar proteinosis and inflammatory infiltrates were markedly reduced, reflected by decreased numbers of CD4 T-cells, CD8 T-cells, and macrophages. The patient was able to wean entirely off systemic corticosteroids and other biologics after 10 months of treatment with MAS-825 and experienced no side effects of the drug. This case demonstrates improvement in pulmonary symptoms, lung inflammation, and burden of immunomodulatory therapy after treatment with MAS-825 and suggests that simultaneous targeting of both IL-1β and IL-18 may be a safe and effective treatment strategy in SJIA-LD.

Immune dysregulation

The understanding of immune dysregulation in many different diseases continues to grow. There is increasing evidence that altered microbiome and gut barrier dysfunction contribute to systemic inflammation in patients with primary immunodeficiency and in patients with rheumatic disease. Recent research provides insight into the process of induction and maturation of pathogenic age-associated B cells and highlights the role of age-associated B cells in creating tissue inflammation. T follicular regulatory cells are shown to help maintain B-cell tolerance, and therapeutic approaches to increase or promote T follicular regulatory cells may help prevent or decrease immune dysregulation. Meanwhile, novel studies of systemic-onset juvenile idiopathic arthritis reveal a strong HLA association with interstitial lung disease and identify key aspects of the pathogenesis of macrophage activation syndrome. Studies of hyperinflammatory syndromes, including the recently described multisystem inflammatory syndrome of children, characterize similarities and differences in cytokine profiles and T-cell activation. This review focuses on recent advances in the understanding of immune dysregulation and describes potential key factors that may function as biomarkers for disease or targets for therapeutic interventions. Future trials are necessary to address the many remaining questions with regards to pathogenesis, diagnosis, and treatment of autoimmune, inflammatory, and immunodeficiency syndromes.

Connective tissue disease with macrophage activation syndrome: A case report

RATIONALE

Macrophage activation syndrome (MAS), or secondary hemophagocytic lymphocytosis (sHLH), is a rare systemic inflammatory response syndrome that is fatal. Adult patients lack clear criteria for diagnosis and treatment, primarily derived from guidelines and protocols for treating family hemophagocytic lymphocytosis and systemic juvenile idiopathic arthritis (sJIA)-related MAS in children or from retrospective case reports. As a subtype of sHLH, MAS has a clinical presentation like sHLH, but treatment varies. Herein, we report the case of a 40-year-old female with MAS caused by a connective tissue disease.

PATIENT CONCERNS

The patient presented to the Rheumatology and Immunology Clinic with recurrent fever and rash, and MAS was confirmed after a series of examinations. The patient had no significant effect after treatment with JAK inhibitors, but after the use of the IL-6 inhibitor tocilizumab, the fever and rash were significantly reduced, and laboratory indicators returned to normal levels.

DIAGNOSIS

Considering the patient's condition and laboratory test results, we judged that the patient had connective tissue disease with MAS.

INTERVENTIONS

We gave sequential treatment of tocilizumab.

OUTCOMES

ALL indicators are mostly back to normal when the patient was monitored at the outpatient clinic.

LESSONS

MAS/HLH lacks clear criteria for diagnosis or treatment in adult patients and is extremely difficult to distinguish from bacterial sepsis or other systemic inflammatory response syndromes. Consequently, early diagnosis and treatment are indispensable for enhancing patient survival.

Biomarkers in Systemic Juvenile Idiopathic Arthritis, Macrophage Activation Syndrome and Their Importance in COVID Era

Systemic juvenile idiopathic arthritis (sJIA) and its complication, macrophage activation syndrome (sJIA-MAS), are rare but sometimes very serious or even critical diseases of childhood that can occasionally be characterized by nonspecific clinical signs and symptoms at onset-such as non-remitting high fever, headache, rash, or arthralgia-and are biologically accompanied by an increase in acute-phase reactants. For a correct positive diagnosis, it is necessary to rule out bacterial or viral infections, neoplasia, and other immune-mediated inflammatory diseases. Delays in diagnosis will result in late initiation of targeted therapy. A set of biomarkers is useful to distinguish sJIA or sJIA-MAS from similar clinical entities, especially when arthritis is absent. Biomarkers should be accessible to many patients, with convenient production and acquisition prices for pediatric medical laboratories, as well as being easy to determine, having high sensitivity and specificity, and correlating with pathophysiological disease pathways. The aim of this review was to identify the newest and most powerful biomarkers and their synergistic interaction for easy and accurate recognition of sJIA and sJIA-MAS, so as to immediately guide clinicians in correct diagnosis and in predicting disease outcomes, the response to treatment, and the risk of relapses. Biomarkers constitute an exciting field of research, especially due to the heterogeneous nature of cytokine storm syndromes (CSSs) in the COVID era. They must be selected with utmost care-a fact supported by the increasingly improved genetic and pathophysiological comprehension of sJIA, but also of CSS-so that new classification systems may soon be developed to define homogeneous groups of patients, although each with a distinct disease.

Pathogenic roles and diagnostic utility of interleukin-18 in autoinflammatory diseases

Interleukin (IL)-18 is a pleiotropic, pro-inflammatory cytokine involved in the regulation of innate and adaptive immune responses. IL-18 has attracted increasing attention as a key mediator in autoinflammatory diseases associated with the development of macrophage activation syndrome (MAS) including systemic juvenile idiopathic arthritis and adult-onset Still’s disease. In these diseases, dysregulation of inflammasome activity and overproduction of IL-18 might be associated with the development of MAS by inducing natural killer cell dysfunction. Serum IL-18 levels are high in patients with these diseases and therefore are useful for the diagnosis and monitoring of disease activity. In contrast, a recent study revealed the overproduction of IL-18 was present in cases of autoinflammation without susceptibility to MAS such as pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome. The pathogenic and causative roles of IL-18 remain unclear in these autoinflammatory diseases. Further investigations are necessary to clarify the role of IL-18 and its importance as a therapeutic target in the pathogenesis of autoinflammatory diseases.

Macrophage activation syndrome in adults: Characteristics, outcomes, and therapeutic effectiveness of etoposide-based regimen

Objectives

To describe the clinical characteristics and outcomes of adult macrophage activation syndrome (MAS) patients and to provide experience for the treatment.

Methods

Adult patients with MAS admitted to Beijing Friendship Hospital from December 2014 to September 2021 were enrolled in this study. Clinical data of patients were collected and analyzed.

Results

A total of 118 adult MAS patients entered this study. MAS was the first manifestation in 43 (36.4%) patients, while 75 (63.6%) developed MAS after the diagnosis of autoimmune disease (AID) with a median diagnostic interval of 2 (0.5–359) months. Eighty-two patients were initially treated with glucocorticoid-based regimen; the overall response (OR) rate at the 2-week posttreatment was 37.8%. Forty-five patients switched to etoposide-based regimen, and the OR rate was 84.4%. Thirty-six patients were initially treated with etoposide-based regimen, and the OR rate at the 2-week posttreatment was 80.6%. Serum IL-18 (P = 0.021), IFN-γ (P = 0.013), IP-10 (P = 0.001), IL-10 (P = 0.041), IL-1RA (P < 0.001), and TNF-α (P = 0.020) levels of patients were significantly decreased in the remission phase than in the active phase. Levels of SDF-1α (P = 0.018) and IL-7 (P = 0.022) were higher in refractory patients, while the GRO-α level had a strong tendency toward statistical significance (P = 0.050). The probability of overall survival (OS) at 3, 6, and 36 months after HLH diagnosis were 89.8%, 89.0%, and 87.9%, retrospectively. The active MAS status at the 2-week post initial treatment [P = 0.009, HR = 15.281, 95% CI, (0.1.972, 118.430)] and baseline neutrophil count (Neu) <1.5 × 10⁹/l [P = 0.017, HR = 3.678, 95% CI, (1.267, 10.672)] were negative prognostic factors.

Conclusion

MAS typically occurs within 2 months after the onset of autoimmune disease in adults. SDF-1α, IL-7, and GRO-α could be used to predict refractory MAS. The etoposide-based regimen is effective and tolerable for adult MAS.

An Evidence-Based Guideline Improves Outcomes for Patients With Hemophagocytic Lymphohistiocytosis and Macrophage Activation Syndrome

OBJECTIVE

To compare clinical outcomes in children with hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) who were managed before and after implementation of an evidence-based guideline (EBG).

METHODS

A management algorithm for MAS-HLH was developed at our institution based on literature review, expert opinion, and consensus building across multiple pediatric subspecialties. An electronic medical record search retrospectively identified hospitalized patients with MAS-HLH in the pre-EBG (October 15, 2015, to December 4, 2017) and post-EBG (January 1, 2018, to January 21, 2020) time periods. Predetermined outcome metrics were evaluated in the 2 cohorts.

RESULTS

After the EBG launch, 57 children were identified by house staff as potential patients with MAS-HLH, and rheumatology was consulted for management. Ultimately, 17 patients were diagnosed with MAS-HLH by the treating team. Of these, 59% met HLH 2004 criteria, and 94% met 2016 classification criteria for MAS complicating systemic juvenile idiopathic arthritis. There was a statistically significant reduction in mortality from 50% before implementation of the EBG to 6% in the post-EBG cohort (P = 0.02). There was a significant improvement in time to 50% reduction in C-reactive protein level in the post-EBG vs pre-EBG cohorts (log-rank P < 0.01). There were trends toward faster time to MAS-HLH diagnosis, faster initiation of immunosuppressive therapy, shorter length of hospital stay, and more rapid normalization of MAS-HLH-related biomarkers in the patients post-EBG.

CONCLUSION

While the observed improvements may be partially attributed to advances in treatment of MAS-HLH that have accumulated over time, this analysis also suggests that a multidisciplinary treatment pathway for MAS-HLH contributed meaningfully to favorable patient outcomes.

[Assessment of MS-Score and HScore in timeliness of diagnosis of macrophage activation syndrome associated with adult-onset Still's disease]

The data of 33 patients with adult-onset still's disease (AOSD)-associated macrophage activation syndrome (MAS) were retrospectively collected from January 2013 to December 2020 in Peking Union Medical College Hospital. Hemophagocytic lymphohistiocytosis (HLH)-2004 criteria, macrophage activation syndrome/juvenile idiopathic arthritis (MS-Score) and hemophagocytic syndrome diagnostic score (HScore) were used to diagnose AOSD-associated MAS, respectively. The time of diagnosis of AOSD-associated MAS by MS-Score was 19.0 (4.5, 31.0) days [M (Q₁,Q₃)] earlier than by HLH-2004 criteria, and 13.5 (0.5, 21.5) days earlier than by HScore (both P<0.05). The difference was not statistically significant between the time of diagnosis of AOSD-associated MAS by Hscore and by HLH-2004 criteria (P>0.05). There was significant difference among the three criteria (P<0.001). MS-Score can be used to diagnose AOSD-associated MAS earlier than HLH-2004 criteria, while the timeliness of HScore is not certain.

Dramatic recovery after etoposide phosphate infusion for hemophagocytic lymphohistiocytosis/macrophage activation syndrome following treatment with tisagenlecleucel in a young patient with relapsed acute lymphoblastic leukemia: a case report

The occurrence of a secondary hemophagocytic lymphohistiocytosis/macrophage activation syndrome (HLH/MAS) after CAR-T cells infusion is very rare and mostly fatal. Treatment recommendations for such a complication are not yet established. Here we report the dramatic recovery of a HLH/MAS following tisagenlecleucel infusion in a young patient with relapsed acute lymphoblastic leukemia using etoposide phosphate (EP). We propose that monitoring for the occurrence of HLH/MAS should be part of surveillance after CAR T-cells infusion and that EP treatment appears to be useful to control this severe and rare complication.

Progressive, refractory macrophage activation syndrome as the initial presentation of anti-MDA5 antibody positive juvenile dermatomyositis: a case report and literature review

BACKGROUND

Macrophage activation syndrome (MAS) is a severe and under-recognized complication of rheumatologic diseases. We describe a patient who presented with rapidly progressive, refractory MAS found to have anti-MDA5 antibody Juvenile Dermatomyositis (JDM) as her underlying rheumatologic diagnosis.

CASE PRESENTATION

We describe a 14-year-old female who at the time of admission had a history of daily fevers for 6 weeks and an unintentional sixteen-pound weight loss. Review of systems was significant for cough, shortness of breath, chest pain, headaches, sore throat, muscle aches, rash, nausea, and loss of appetite. An extensive initial workup revealed findings consistent with an autoimmune process. While awaiting results of her workup she had clinical decompensation with multi-organ system involvement including pancytopenias, interstitial lung disease, hepatitis, cardiac involvement, gastrointestinal distension and pain, feeding intolerance, extensive mucocutaneous candidiasis, and neuropsychiatric decline. Due to her decompensation, significant interstitial lung disease, and likely underlying rheumatologic condition she was started on high dose pulse steroids and mycophenolate. An MRI was performed due to her transaminitis and shoulder pain revealing significant myositis. Intravenous immunoglobulin was then initiated. The myositis antibody panel sent early in her workup was significant for anti-MDA5 and anti-SSA-52 antibodies. Despite high dose pulse steroids, mycophenolate, and IVIG, her disease progressed requiring escalating therapies. Ultimately, she responded with resolution of her MAS as well as significant and steady improvement in her feeding intolerance, interstitial lung disease, cardiac dysfunction, myositis, arthritis, and cutaneous findings.

CONCLUSIONS

JDM in the pediatric patient is rare, as is MAS. In patients with complex rheumatologic conditions and lack of response to treatment, it is important to continually assess the patient's clinical status with MAS in mind, as this may change the treatment approach. Without proper recognition of this complication, patients can have a significant delay in diagnosis leading to life-threatening consequences.

Macrophage activation syndrome in patients with adult-onset Still's disease under tocilizumab treatment: A single-center observational study

OBJECTIVES

Macrophage activation syndrome (MAS) developed under tocilizumab treatment poses a diagnostic challenge. This study aims to demonstrate the frequency and the clinical features of MAS developed in patients with adult-onset Still's disease (AOSD) receiving tocilizumab.

METHODS

The consecutive AOSD patients treated with tocilizumab in our institution from April 2008 to March 2020 were studied. The frequency of clinically diagnosed MAS during tocilizumab treatment, their conformity to the several criteria relevant for MAS, and laboratory characteristics compared to AOSD flare were investigated.

RESULTS

Of the 20 AOSD patients treated with tocilizumab, six developed clinically diagnosed MAS, four immediately after starting tocilizumab and two after long-term treatment. Some of them had already met the MAS criteria before starting tocilizumab. At MAS diagnosis, although some did not meet the MAS criteria due to lack of fever and/or the lower ferritin levels, all consistently showed sharp increases in ferritin along with marked abnormal changes in two or more different markers of organ damage, unlike the AOSD flares.

CONCLUSION

MAS is not a rare complication in AOSD patients receiving tocilizumab. The clinical similarities between systemic AOSD and MAS, and substantial alterations in MAS features by inhibition of interleukin-6 signaling may limit the utility of the existing diagnostic/classification criteria in diagnosing MAS under tocilizumab treatment. The emergence of abnormalities in MAS-related organ damage markers with a rapid elevation of ferritin should be considered as MAS development in AOSD patients receiving tocilizumab even if the patients are afebrile or have relatively low ferritin levels.

Macrophage Activation Syndrome secondary to Systemic Juvenile Idiopathic Arthritis: A Case Report

Macrophage activation syndrome is a rare but a life threatening condition commonly associated with Systemic Juvenile Idiopathic Arthritis. Its clinical presentation includes fever, hepatosplenomegaly, hypertriglyceridemia, hypofibrinogenemia, hyperferritinemia and impaired liver enzymes. The symptoms are alarming yet non-specific and often lead to a delayed diagnosis. A 12 year male presented with a history of intermittent fever and was started on antibiotics but failed to respond after several days of hospital stay. After a series of investigations to rule out multiple diagnoses he was diagnosed as a case of Macrophage Activation Syndrome secondary to Systemic onset Juvenile Arthritis and was treated with steroids.

A Recurrent Case of Adult-onset Still's Disease with Concurrent Acalculous Cholecystitis and Macrophage Activation Syndrome/Hemophagocytic Lymphohistiocytosis Successfully Treated with Combination Immunosuppressive Therapy

We herein report the case of 21-year-old female diagnosed with adult-onset Still's disease (AOSD) three years earlier who presented with fever and right upper abdominal pain. She was diagnosed with acute acalculous cholecystitis (AAC) based on hepatic dysfunction, elevated C-reactive protein, and gallbladder wall thickening on abdominal ultrasound. Based on the presence of pancytopenia, hyperferritinemia, and hemophagocytosis by a bone marrow examination, she was diagnosed with macrophage activation syndrome (MAS)/hemophagocytic lymphohistiocytosis (HLH) which was refractory to glucocorticoid pulse therapy. The combination of intravenous cyclosporine A with glucocorticoids was able to successfully control the disease activity of AOSD-related AAC and MAS/HLH.