Macrophage activation syndrome complicating adult onset Still’s disease: A single center case series and comparison with literature

Emapalumab Treatment in Patients With Rheumatologic Disease-Associated Hemophagocytic Lymphohistiocytosis in the United States: A Retrospective Medical Chart Review Study

OBJECTIVE

Rheumatologic disease-associated hemophagocytic lymphohistiocytosis (HLH), a rare, life-threatening, systemic hyperinflammatory syndrome, occurs as a complication of underlying rheumatologic disease. Real-world evidence is lacking on emapalumab, a fully human monoclonal antibody that neutralizes the proinflammatory cytokine interferon-γ, approved for treating patients with primary HLH.

METHODS

REAL-HLH, a retrospective medical chart review study conducted across 33 US hospitals, assessed real-world treatment patterns and outcomes in patients with HLH treated with one or more dose of emapalumab between November 20, 2018, and October 31, 2021. Data are presented for the subset of patients with rheumatologic disease-associated HLH.

RESULTS

Fifteen of 105 patients (14.3%) had rheumatologic disease-associated HLH. Of these, nine (60.0%) had systemic juvenile idiopathic arthritis, and one (6.7%) had adult-onset Still disease. Median (range) age at HLH diagnosis was 5 (0.9-39) years. Most patients (9 of 15; 60.0%) initiated emapalumab in an intensive care unit. Emapalumab was most frequently initiated for treating refractory or recurrent (10 of 15; 66.7%) disease. Most patients received HLH-related therapies before (10 of 15; 66.7%) and concurrently with (15 of 15; 100.0%) emapalumab. Emapalumab-containing regimens stabilized or achieved physician-determined normalization of most laboratory parameters, including absolute neutrophil count and absolute lymphocyte count (13 of 14; 92.9%), chemokine ligand 9 (9 of 11; 81.8%), and platelets and alanine transaminase (11 of 14; 78.6%), and reduced glucocorticoid dose by 80%. Overall survival and 12-month survival probability from emapalumab initiation were 86.7%.

CONCLUSION

Emapalumab-containing regimens stabilized or normalized most key laboratory parameters, reduced glucocorticoid dose, and were associated with low disease-related mortality, thereby demonstrating potential benefits in patients with rheumatologic disease-associated HLH.

Still's Disease Onset in Older Adults: Clinical Features, Diagnosis, and Management

Still's disease (SD) is a rare systemic inflammatory disease that is characterized by high fever, polyarthritis, and an evanescent rash as its main symptoms but that may also be complicated by pleuritis and macrophage activation syndrome (MAS). There has been a recent increase in studies on older-onset SD, which presents with less-typical clinical features, such as sore throat, skin lesions, and splenomegaly, but more complications including pleuritis and disseminated intravascular coagulation. Several reports have shown higher levels of inflammatory markers, including serum ferritin, and poorer outcomes in terms of survival and drug-free remission in older patients. In addition, caution is needed when diagnosing SD in older patients because of the increased incidence of differential diagnoses such as infectious diseases, malignancies, and inflammatory diseases. Prognosis is poor in older patients, and treatment-associated infections and severe complications such as MAS are the main cause of mortality. The use of biologics and treatment response may not differ greatly between older and younger patients. Although the data are limited, anti-IL-1 and anti-IL-6 agents may control SD in these patients with careful use and adequate infection prevention. Recent studies that classified adult-onset SD by cluster analysis or latent class analysis showed that older patients form a unique cluster of SD, indicating the need for clinicians to pay more attention to the diagnosis and management of SD in older patients.

Nationwide Analysis of Adult-Onset Still Disease With and Without Hemophagocytic Lymphohistiocytosis

INTRODUCTION

Adult-onset Still disease (AOSD) is a rare inflammatory condition with a monophasic, intermittent, or chronic clinical course, and a subset may experience life-threatening complications such as hemophagocytic lymphohistiocytosis (HLH). This study aims to characterize concurrent AOSD and HLH and identify variables independently associated with in-hospital death.

METHODS

We performed a medical records review of AOSD with and without HLH from the 2016-2019 National Inpatient Sample database. We performed a multivariable logistic regression analysis for in-hospital death. Results were reported as adjusted odds ratios (OR adj ).

RESULTS

There were 5495 hospitalizations with AOSD, of which 340 (6.2%) had HLH. Thirty (9.0%) of the combined AOSD and HLH group died in the hospital compared with 75 (1.5%) of those without HLH. Multivariable analysis in AOSD inpatients showed that disseminated intravascular coagulation (OR adj 6.13), hepatic failure (OR adj 7.16), infection (OR adj 3.72), respiratory failure (OR adj 6.89), and thrombotic microangiopathy (OR adj 14.05) were associated with higher odds of death. However, HLH itself was not an independent predictor of mortality in AOSD population.

CONCLUSIONS

HLH occurred in a small minority of inpatients with AOSD. HLH itself was not an independent risk factor for in-hospital death. Disseminated intravascular coagulation, hepatic failure, infection, respiratory failure, and thrombotic microangiopathy were associated with higher odds of in-hospital death in AOSD. Better awareness of these life-threatening complications may improve hospital outcomes.

Tailoring the treatment of inflammatory rheumatic diseases by a better stratification and characterization of the clinical patient heterogeneity. Findings from a systematic literature review and experts' consensus

Inflammatory rheumatic diseases are different pathologic conditions associated with a deregulated immune response, codified along a spectrum of disorders, with autoinflammatory and autoimmune diseases as two-end phenotypes of this continuum. Despite pathogenic differences, inflammatory rheumatic diseases are commonly managed with a limited number of immunosuppressive drugs, sometimes with partial evidence or transferring physicians' knowledge in different patients. In addition, several randomized clinical trials, enrolling these patients, did not meet the primary pre-established outcomes and these findings could be linked to the underlying molecular diversities along the spectrum of inflammatory rheumatic disorders. In fact, the resulting patient heterogeneity may be driven by differences in underlying molecular pathology also resulting in variable responses to immunosuppressive drugs. Thus, the identification of different clinical subsets may possibly overcome the major obstacles that limit the development more effective therapeutic strategies for these patients with inflammatory rheumatic diseases. This clinical heterogeneity could require a diverse therapeutic management to improve patient outcomes and increase the frequency of clinical remission. Therefore, the importance of better patient stratification and characterization is increasingly pointed out according to the precision medicine principles, also suggesting a new approach for disease treatment. In fact, based on a better proposed patient profiling, clinicians could more appropriately balance the therapeutic management. On these bases, we synthetized and discussed the available literature about the patient profiling in regard to therapy in the context of inflammatory rheumatic diseases, mainly focusing on randomized clinical trials. We provided an overview of the importance of a better stratification and characterization of the clinical heterogeneity of patients with inflammatory rheumatic diseases identifying this point as crucial in improving the management of these patients.

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

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

Unleashing the Cytokine Storm: A Case of Macrophage Activation Syndrome in Systemic Lupus Erythematosus

Macrophage activation syndrome (MAS), synonymous with secondary hemophagocytic lymphohistiocytosis (HLH), is a rare and critical complication of rheumatologic disease stemming from the unregulated activation and rapid multiplication of macrophages and T lymphocytes. While it primarily manifests in children diagnosed with systemic juvenile idiopathic arthritis (sJIA), it can arise less frequently in other rheumatologic conditions. Here, we outline the clinical course, treatment, and outcome of MAS diagnosed in an 18-year-old female previously diagnosed with SLE who exhibited a unique clinical presentation.

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

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

Macrophage Activation Syndrome in the Setting of Rheumatic Diseases

Patients with established rheumatic disorders may develop complications of macrophage activation syndrome due to severe flares of the underlying disease (adult-onset Still's disease, SLE); however, in most other rheumatic disorders, MAS develops in association with identified viral or other infectious triggers. It is therefore important to pursue appropriate studies to identify potential infectious triggers in rheumatic disease patients who develop MAS. Management is best directed toward treatment of the triggering infections and combinations of high-dose corticosteroids, calcineurin inhibitors, and biologic therapies targeting IL-1 and/or IL-6 to suppress the associated cytokine storm.

IL-1 Family Blockade in Cytokine Storm Syndromes

Interleukin-1 is a prototypic proinflammatory cytokine that is elevated in cytokine storm syndromes (CSSs), such as secondary hemophagocytic lymphohistiocytosis (sHLH) and macrophage activation syndrome (MAS). IL-1 has many pleotropic and redundant roles in both innate and adaptive immune responses. Blockade of IL-1 with recombinant human interleukin-1 receptor antagonist has shown efficacy in treating CSS. Recently, an IL-1 family member, IL-18, has been demonstrated to be contributory to CSS in autoinflammatory conditions, such as in inflammasomopathies (e.g., NLRC4 mutations). Anecdotally, recombinant IL-18 binding protein can be of benefit in treating IL-18-driven CSS. Lastly, another IL-1 family member, IL-33, has been postulated to contribute to CSS in an animal model of disease. Targeting of IL-1 and related cytokines holds promise in treating a variety of CSS.

Etoposide Therapy of Cytokine Storm Syndromes

Etoposide has revolutionized the treatment of primary as well as secondary hemophagocytic lymphohistiocytosis (HLH), and it is, together with corticosteroids, the most widely used therapy for HLH. In the early 1980s, long-term survival in primary HLH was <5% but with the etoposide-/dexamethasone-based protocols HLH-94 and HLH-2004, in combination with stem cell transplantation, 5-year survival increased dramatically to around 60% in primary HLH, and based on analyses from the HLH-2004 study, there is likely room for further improvement. Biologically, etoposide administration results in potent selective deletion of activated T cells as well as efficient suppression of inflammatory cytokine production. Moreover, etoposide has also been reported to promote programmed cell death (apoptosis) rather than proinflammatory lytic cell death (pyroptosis), conceivably ameliorating subsequent systemic inflammation, i.e., a treatment very suitable for cytokine storm syndromes (CSS). The combination of etoposide and corticosteroids may also be beneficial in cases of severe or refractory secondary HLH (sHLH) with imminent organ failure, such as infection-associated HLH caused by Epstein-Barr virus (EBV) or malignancy-triggered HLH. In CSS associated with rheumatic diseases (macrophage activation syndrome, MAS or MAS-HLH), etoposide is currently used as second- or third-line therapy. Recent studies suggest that etoposide perhaps should be part of an aggressive therapeutic intervention for patients with severe refractory or relapsing MAS, in particular if there is CNS involvement. Importantly, awareness of sHLH must be further increased since treatment of sHLH is often delayed, thereby missing the window of opportunity for a timely, effective, and potentially life-saving HLH-directed treatment.

Expert consensus on the treatment of patients with adult-onset still's disease with the goal of achieving an early and long-term remission

We performed a comprehensive systematic targeted literature review and used the Delphi method to formulate expert consensus statements to guide the treatment of adult-onset Still's disease (AOSD) to achieve an early and long-term remission. Seven candidate statements were generated and reached consensus in the first round of voting by the panel of experts. We postulate: (i) In patients with AOSD with predominant arthritis at onset who achieved no disease control with glucocorticoids (GCs), the use of methotrexate can be considered, whereas the use of cyclosporin A and low-dose GCs should not (Statements 1-3); (ii) In patients with AOSD with poor prognostic factors at diagnosis, an IL-1 inhibitor (IL-1i) in addition to GCs should be taken into consideration as early as possible (Statement 4); (iii) A switch to an IL-6 inhibitor (IL-6i) may be considered in patients with AOSD with prevalent joint involvement, who are unresponsive or intolerant to IL-1i (Statement 5); (iv) Drug tapering or discontinuation may be considered in patients who achieved a sustained clinical and laboratory remission with IL-1i (Statement 6); (v) In patients with AOSD who failed to attain a good clinical response with an IL-1i, switching to an IL-6i may be considered in alternative to a different IL-1i. TNF-inhibitors may be considered as a further choice in patients with a prominent joint involvement (Statement 7). These statements will help clinicians in treatment decision making in patients with AOSD.

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.

A Streamlined Diagnostic Process Improved the Outcomes of Patients with Adult-Onset Still's Disease: A Single-Center Retrospective Observational Study

INTRODUCTION

The diagnosis of adult-onset Still's disease (AOSD) is often delayed due to its clinical heterogeneity and lack of pathognomic features. Hence, there is an unmet need for an efficient diagnostic process. The major aim of this study was to compare the differences in disease outcomes between two groups of AOSD patients with and without implementation of the streamlined diagnostic process (SDP).

METHODS

Of 172 febrile patients with skin rash and/or arthralgia, 112 individuals had AOSD. The tentative diagnosis of AOSD or non-AOSD was made with or without the SDP implementation. The selection criteria for AOSD outcomes analysis were as follows: (1) age at study entry older than 20 years, (2) fulfillment of the Yamaguchi criteria for AOSD diagnosis, and (3) a follow-up period longer than 6 months after initiation of therapy. Three outcome parameters were evaluated, including diagnosis lag period, the proportion of "early diagnosis," and the proportion of achieving disease remission after a 6-month therapy.

RESULTS

The SDP was implemented for expediting AOSD diagnosis in 41 (36%) enrolled patients (SDP-implemented group). The diagnosis lag period was significantly shorter in the SDP-implemented group (median 2.0 weeks, interquartile range [IQR] 1.0-2.5 weeks) than in the non-SDP-implemented group (4.0 weeks, IQR 2.0-6.0 weeks, p < 0.001). A significantly higher proportion of "early diagnosis" was also found in the SDP-implemented group (75.6%) compared with the non-SDP-implemented group (33.8%, p < 0.001). We revealed a significantly higher proportion of achieving remission in the SDP-implemented group (85.4%) compared with the non-SDP-implemented group (67.6%, p < 0.05). Logistic regression analysis revealed SDP implementation as a potential predictor of achieving disease remission.

CONCLUSIONS

Implementing an SDP for expediting diagnosis could improve outcomes for AOSD patients. This diagnostic process increased the early diagnosis rate and led to a higher disease remission rate. However, the beneficial effects of SDP implementation need further external validation.

The Spectrum of Still's Disease: A Comparative Analysis of Phenotypic Forms in a Cohort of 238 Patients

Still's disease (SD) is a heterogeneous autoinflammatory disorder for which several phenotypes have been described. We conducted a retrospective study to re-evaluate the dichotomous view of the disease, to compare the juvenile and adult forms, and to look for prognostic factors. We collected data from ten French centers, seeking patients with a diagnosis of adult-onset SD (AOSD) or systemic juvenile idiopathic arthritis (sJIA). We identified 238 patients, 152 (64%) of whom had AOSD while 86 (36%) had sJIA. The median age at SD onset was 26.6 years. In patients with identifiable patterns, the course of SD was systemic in 159 patients (74%), chronic in 55 (26%). Sore throat and myalgia were more frequent in patients with AOSD. Abnormal liver tests, serum ferritin and C-reactive protein levels were higher in AOSD group. Fever and skin rash were predictive of complete remission or recovery and high lactate dehydrogenase level was a poor prognosis factor. Symptoms such as splenomegaly, skin rash, high polymorphonuclear neutrophils count and macrophage activation syndrome were predictive of a systemic phenotype. Overall, there were no major differences between sJIA and AOSD. Our results are consistent with the "biphasic" model of an autoinflammatory disease that can progress to chronic arthritis if not treated early.

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

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

Interleukin-18: a biomarker with therapeutic potential in adult-onset Still's disease

INTRODUCTION

Adult-onset Still's disease (AOSD) is an autoinflammatory disease driven by the innate immune response. Given the ambiguity in clinical presentation and lack of specific diagnostic biomarkers, AOSD diagnosis is usually delayed in the early stage. Because AOSD is a rare disease with clinical heterogeneity, there is no consensus on its treatment currently. This review summarizes the current research evidence regarding the pathogenic role and the diagnostic or therapeutic potential of interleukin (IL)-18 in AOSD.

AREAS COVERED

We searched the MEDLINE database using the PubMed interface and reviewed English-language literature from 1971 to 2022. This review focusing on IL-18 discusses its pathogenic role and clinical implications in AOSD.

EXPERT OPINION

NLRP3-inflammasome activation with IL-18 overproduction plays a pathogenic role in AOSD. IL-18 is closely linked to the clinical manifestations and disease activity of AOSD and may be a diagnostic biomarker. Given its pathogenic role in AOSD, IL-18 could become a potential therapeutic target. IL-18 binding protein (IL-18BP) negatively regulates the biological activity of IL-18 by inhibiting IL-18 signaling, and a clinical trial revealed that IL-18BP (Tadekinig alfa) treatment was well-tolerated and effective for AOSD. Recently, monoclonal antibodies against IL-18 have been under evaluation in a phase 1b trial.

Infection-Triggered Hyperinflammatory Syndromes in Children

An association between infectious diseases and macrophage activation syndrome (MAS) has been reported, yet the exact role of infection in MAS development is still unclear. Here, a retrospective analysis of the clinical records of patients with rheumatic diseases complicated with MAS who were treated in a pediatric tertiary care center between 2011 and 2020 was performed. Any infection documented within the 30 days preceding the onset of MAS was reported. Out of 125 children in follow-up for systemic rheumatic diseases, 12 developed MAS, with a total of 14 episodes. One patient experienced three episodes of MAS. Clinical and/or laboratory evidence of infection preceded the onset of MAS in 12 events. Clinical features, therapeutic strategies, and patient outcomes were described. The aim of this study was to evaluate the possible role of infection as a relevant trigger for MAS development in children with rheumatic conditions. The pathogenetic pathways involved in the cross-talk between uncontrolled inflammatory activity and the immune response to infection deserve further investigation.

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.

Catastrophic adult-onset Still's disease as a distinct life-threatening clinical subset: case-control study with dimension reduction analysis

Objectives

Adult-onset Still’s disease (AOSD) is a rare systemic inflammatory disorder. Diagnosing AOSD can be challenging, as disease presentation and clinical course are highly heterogeneous. For unclear reasons, a few patients develop life-threatening complications. Our objective was to determine whether these cases resulted from therapeutic delay or could represent a peculiar AOSD subset.

Methods

We conducted a multicentre retrospective study of 20 AOSD patients with organ failure requiring intensive care unit admission and 41 control AOSD patients without organ failure. Clinico-biological data at hospital admission were explored using supervised analyses and unsupervised dimension reduction analysis (factor analysis of mixed data, FAMD).

Results

Disease duration before admission was shorter in patients with life-threatening AOSD (median, 10 vs 20 days, p = 0.007). Disease duration before AOSD therapy initiation also tended to be shorter (median, 24 vs 32 days, p = 0.068). Despite this shorter disease duration, FAMD, hierarchical clustering and univariate analyses showed that these patients exhibited distinctive characteristics at first presentation, including younger age; higher frequency of splenomegaly, liver, cardiac and/or lung involvement; less frequent arthralgia; and higher ferritin level. In multivariate analysis, 3 parameters predicted life-threatening complications: lack of arthralgia, younger age and shorter time between fever onset and hospitalisation.

Conclusion

This study suggests that life-threatening complications of AOSD occur very early, in a peculiar subset, which we propose to name catastrophic adult-onset Still’s disease (CAOSD). Its exact burden may be underestimated and remains to be clarified through large multicentre cohorts. Further studies are needed to identify red flags and define the optimal therapeutic strategy.

The effectiveness of tocilizumab in treating refractory adult-onset Still's disease with dichotomous phenotypes: IL-18 is a potential predictor of therapeutic response

OBJECTIVE

Adult-onset Still's disease (AOSD) is a systemic inflammatory disorder with clinical heterogeneity. Although tocilizumab (TCZ), an interleukin (IL)-6 receptor inhibitor, is an effective treatment for AOSD, the evidence regarding its efficacy on systemic or articular subtypes is conflicting. Furthermore, the predictors of therapeutic response are still elusive and worthy of exploration.

METHODS

This two-center retrospective study analyzed the effectiveness and safety profile of TCZ treatment in 28 patients with refractory AOSD. The 28-joint disease activity score (DAS28) and systemic activity score were assessed before and during TCZ treatment period at weeks 12, 24, 36, and 48. Plasma levels of proinflammatory cytokines at baseline were determined using ELISA method.

RESULTS

Among the systemic subtype patients, 10 (58.8%), 13 (76.5%), 14 (82.4%), and 15 (88.2%) patients achieved complete remission at week 12, 24, 36, and 48, respectively, in comparison to 2 (22.2%), 5 (55.6%), 6 (66.7%), and 7 (77.8%) who achieved disease remission (DAS28 < 2.6) at weeks 12, 24, 36, and 48, respectively, among articular subtype patients. The systemic activity scores and inflammatory parameters were significantly decreased after 12-week TCZ therapy, and TCZ could significantly reduce corticosteroid dose in AOSD patients. Multivariate analysis reveals that baseline IL-18 level is a significant predictor of poor therapeutic response at week 24 (odds ratio 7.86, p < 0.05).

CONCLUSION

AOSD patients refractory to high-dose corticosteroids and methotrexate may respond well to TCZ treatment with a steroid-sparing effect and an acceptable safety. A high baseline IL-18 level may be a predictor of poor therapeutic response. Key Points • Tocilizumab may be effective and well-tolerated in refractory AOSD patients regardless of disease subtypes. • High plasma levels of IL-18 may predict poor response to tocilizumab in AOSD patients.

Adult-onset Still's disease with neurological involvement: a single-centre report

OBJECTIVES

Adult-onset Still's disease (AOSD) is a multifactorial systemic autoinflammatory disease. Neurological damage has been rarely reported in AOSD. We aimed to characterize the clinical features of AOSD patients with neurological involvement.

METHODS

A total of 187 AOSD patients were admitted to Peking Union Medical College Hospital from January 2015 to August 2019. The complete medical records were reviewed in this retrospective study. Clinical features of 14 AOSD patients with neurological involvement were collected and compared with those without.

RESULTS

The prevalence of neurological involvement in AOSD inpatients was 7.5%. The median disease duration was 4.5 months, with a range of 1-15 months. The frequent symptoms were fever [14 (100%)], rash [13 (92.9%)], liver dysfunction [11 (78.6%)], arthralgia/arthritis [10 (71.4%)] and lymphadenopathy [10 (71.4%)]. Four (28.6%) patients had macrophage activation syndrome (MAS). Aseptic meningitis was the most common presentation (64.3%) when the nervous system was involved. Other rare manifestations included cranial nerve palsy, encephalitis and cerebral infarction. The rate of MAS, serum levels of lactate dehydrogenase and ferritin were significantly higher in AOSD patients with neurological involvement than in those without. All patients received high-dose corticosteroid therapy and immunosuppressive agents and two were given tocilizumab. Clinical remission was achieved in all 14 AOSD patients with neurological involvement.

CONCLUSION

Neurological involvement, particularly aseptic meningitis, is not a rare complication of AOSD. It is frequently complicated by MAS. There may be a potential relationship between the neurological damage of AOSD and MAS.

Interleukin-18 Is a Potential Biomarker to Discriminate Active Adult-Onset Still's Disease From COVID-19

Background

Hyperinflammation with dysregulated production of galectins and cytokines may develop in COVID-19 or adult-onset Still's disease (AOSD). Given the similar clinical features in both diseases, it is necessary to identify biomarkers that can differentiate COVID-19 from AOSD. However, the related data remain scarce currently.

Methods

In this cross-sectional study, plasma levels of galectin-3, galectin-9, and soluble TIM-3 (sTIM-3) were determined by ELISA in 55 COVID-19 patients (31 non-severe and 24 severe), 23 active AOSD patients, and 31 healthy controls (HC). The seropositivity for SARS-CoV-2 was examined using an immunochromatographic assay, and cytokine profiles were determined with the MULTIPLEX platform.

Results

Significantly higher levels of galectin-3, galectin-9, IL-1β, IL-1Ra, IL-10, IFN-α2, IL-6, IL-18, and TNF-α were observed in severe COVID-19 and active AOSD patients compared with HC (all p<0.001). AOSD, but not COVID-19, showed significantly higher IFN-γ and IL-17A compared with HC (both p<0.01). Moreover, active AOSD patients had 68-fold higher IL-18 levels and 5-fold higher ferritin levels than severe COVID-19 patients (both p<0.001). IL-18 levels at the cut-off value 190.5pg/mL had the highest discriminative power for active AOSD and severe COVID-19, with AUC 0.948, sensitivity 91.3%, specificity 95.8%, and accuracy of 91.5% (p<0.005). Multivariate regression analysis revealed IL-18 as a significant predictor of active AOSD (p<0.05).

Conclusion

Active AOSD patients share features of hyperinflammation and cytokine storm with severe COVID-19 patients but possess a distinct cytokine profile, including elevated IL-18, IL-6, IFN-γ, and IL-17A. IL-18 is a potential discriminator between AOSD and COVID-19 and may significantly predict active AOSD.

Amyloid storm: acute kidney injury and massive proteinuria, rapidly progressing to end-stage kidney disease in AA amyloidosis of familial Mediterranean fever

OBJECTIVE

Amyloid A nephropathy of FMF usually progresses over many years to end-stage renal disease (ESRD). We aim to describe an acute condition, termed here 'amyloid storm', typically manifesting with a rapid (≤2 weeks) increase in serum creatinine and urine protein, that has never been characterized in FMF amyloidosis.

METHODS

This retrospective analysis features amyloid storm by comparing between FMF amyloidosis patients who have experienced an episode of amyloid storm (study group) and matched patients who have not (control group). The primary outcome was ESRD or death within 1 year from study entry. Featured data were retrieved from hospital files.

RESULTS

The study and control groups, each comprising 20 patients, shared most baseline characteristics. However, they differed on the time from FMF onset to reaching serum creatinine of 1.2 mg/dl [26.5 years (s.d. 15.15) vs 41.55 (10.98), P = 0.001] and the time from the onset of proteinuria to study entry [8.8 years (s.d. 6.83) vs 15.75 (13.05), P = 0.04], culminating in younger age at study entry [39.95 years (s.d. 16.81) vs 48.9 (9.98), respectively, P = 0.05] and suggesting an accelerated progression of kidney disease in the study group. Within 1 year from study entry, 16 patients in the study and 3 in the control groups reached the primary endpoint (P = 0.000). The major triggers of amyloid storm were infections, occurring in 17 of 20 patients.

CONCLUSION

Amyloid storm is a complication of FMF amyloidosis, induced by infection and associated with poor prognosis and death.

An Update on the Pathogenic Role of Macrophages in Adult-Onset Still's Disease and Its Implication in Clinical Manifestations and Novel Therapeutics

Increasing evidence indicates a pivotal role of macrophages in innate immunity, which contributes to the pathogenesis of adult-onset Still's disease (AOSD). Despite the available reviews that summarized the pathogenic role of proinflammatory cytokines in AOSD, a systematic approach focusing on the crucial role of macrophages in this disease is still lacking. This review summarizes the updated functions of macrophages in AOSD and their implication in clinical manifestations and therapeutics. We searched the MEDLINE database using the PubMed interface and reviewed the English-language literature as of 31 March 2021, from 1971 to 2021. We focus on the existing evidence on the pathogenic role of macrophages in AOSD and its implication in clinical characteristics and novel therapeutics. AOSD is an autoinflammatory disease mainly driven by the innate immune response. Among the innate immune responses, macrophage activation is a hallmark of AOSD pathogenesis. The pattern recognition receptors (PRRs) on macrophages recognize pathogen-associated molecular patterns and damage-associated molecular patterns and subsequently cause overproduction of proinflammatory cytokines and recruit adaptive immunity. Some biomarkers, such as ferritin and gasdermin D, reflecting macrophage activation were elevated and correlated with AOSD activity. Given that macrophage activation with the overproduction of proinflammatory cytokines plays a pathogenic role in AOSD, these inflammatory mediators would be the therapeutic targets. Accordingly, the inhibitors to interleukin- (IL-) 1, IL-6, and IL-18 have been shown to be effective in AOSD treatment. Gaining insights into the pathogenic role of macrophages in AOSD can aid in identifying disease biomarkers and therapeutic agents for this disease.

Systemic autoinflammatory disease in adults

Systemic autoinflammatory disorders comprise an expanding group of rare conditions. They are mediated by dysfunction of the innate immune system and share a core of phenotypic manifestations including recurrent attacks of fever, cutaneous signs, chest or abdominal pain, lymphadenopathy, vasculopathy, and musculoskeletal symptoms. Diagnosis is often established in childhood, but a growing number of adult patients are being recognized with systemic autoinflammatory disorders, including adult-onset disease. In this review, we provide a concise update on the pathophysiology, clinical presentation, and diagnostic approach of systemic autoinflammatory disorders with an emphasis on the adult patient population. Despite the recent advances in genetic testing, the diagnosis of autoinflammatory disease in adult patients is often based on a thorough knowledge of the clinical phenotype. Becoming acquainted with the clinical features of these rare disorders may assist in developing a high index of suspicion for autoinflammatory disease in patients presenting with unexplained episodes of fever or inflammation.

Risk of macrophage activation syndrome in patients with adult-onset Still's disease with skin involvement: A retrospective cohort study

BACKGROUND

Small case series and case reports indicated that atypical persistent pruritic eruptions (PPEs), another type of skin lesions seen in adult-onset Still's disease (AOSD), imply a worse prognosis than typical evanescent rashes.

OBJECTIVE

To investigate clinical characteristics and macrophage activation syndrome (MAS) occurrence in AOSD with PPEs.

METHODS

A retrospective cohort study analyzed 150 patients with AOSD with rashes at the First Affiliated Hospital of Zhejiang University from January 2013 to December 2019.

RESULTS

Patients with AOSD with PPEs had higher lactate dehydrogenase (492.00 U/L vs 382.00 U/L; P < .001) and ferritin (6944.10 ng/ml vs 4286.60 ng/ml; P = .033), and lower fibrinogen (5.05 g/L vs 5.77 g/L; P = .014) than those with evanescent rashes. Patients with AOSD with PPEs had a higher incidence (17.4% vs 3.1%, P = .006) and cumulative event rate for MAS (P = .008) and tended to receive high-dose glucocorticoid (36% vs 20.3%; P = .036). Multivariate analysis indicated that PPEs (hazard ratio [HR], 5.519; 95% confidence interval [CI], 1.138-26.767; P = .034), aspartate aminotransferase of greater than 120 U/L (HR, 8.084; 95% CI, 1.728-37.826; P = .008), and splenomegaly (HR, 21.152; 95% CI, 2.263-197.711; P = .007) were independent risk factors for MAS.

LIMITATIONS

Single-center, retrospective nature, small sample size.

CONCLUSION

PPEs indicated increased severity and MAS occurrence versus evanescent rashes. PPEs, aspartate aminotransferase of greater than 120 U/L, and splenomegaly were risk factors for MAS in AOSD with skin involvement.

Interleukin 1α: a comprehensive review on the role of IL-1α in the pathogenesis and treatment of autoimmune and inflammatory diseases

The interleukin (IL)-1 family member IL-1α is a ubiquitous and pivotal pro-inflammatory cytokine. The IL-1α precursor is constitutively present in nearly all cell types in health, but is released upon necrotic cell death as a bioactive mediator. IL-1α is also expressed by infiltrating myeloid cells within injured tissues. The cytokine binds the IL-1 receptor 1 (IL-1R1), as does IL-1β, and induces the same pro-inflammatory effects. Being a bioactive precursor released upon tissue damage and necrotic cell death, IL-1α is central to the pathogenesis of numerous conditions characterized by organ or tissue inflammation. These include conditions affecting the lung and respiratory tract, dermatoses and inflammatory skin disorders, systemic sclerosis, myocarditis, pericarditis, myocardial infarction, coronary artery disease, inflammatory thrombosis, as well as complex multifactorial conditions such as COVID-19, vasculitis and Kawasaki disease, Behcet's syndrome, Sjogren Syndrome, and cancer. This review illustrates the clinical relevance of IL-1α to the pathogenesis of inflammatory diseases, as well as the rationale for the targeted inhibition of this cytokine for treatment of these conditions. Three biologics are available to reduce the activities of IL-1α; the monoclonal antibody bermekimab, the IL-1 soluble receptor rilonacept, and the IL-1 receptor antagonist anakinra. These advances in mechanistic understanding and therapeutic management make it incumbent on physicians to be aware of IL-1α and of the opportunity for therapeutic inhibition of this cytokine in a broad spectrum of diseases.

Efficacy of high-dose anakinra in refractory macrophage activation syndrome in adult-onset Still's disease: when dosage matters in overcoming secondary therapy resistance

Macrophage activation syndrome (MAS) is a severe, potentially fatal complication of rheumatic diseases. This case demonstrates the significant challenges and therapeutic considerations in adult-onset Still’s disease (AOSD) complicated with MAS at initial presentation, which will be discussed. MAS in our patient was refractory to the first-line therapy with high-dose corticosteroids, early administration of anakinra at a standard dosage and subsequent add-on treatments with cyclosporine A, IVIG, etoposides and tocilizumab. At 2 months after presentation, the patient was still critically ill with clinical, laboratory and histological signs of an active uncontrolled MAS. Notably, adoption of anakinra at a high dosage finally induced remission. This case confirms that adjusted dosage of anakinra is an effective therapeutic strategy in a severe AOSD-related MAS. It is tempting to speculate that anakinra at a high dosage, if used earlier, would have significantly changed the course of the disease in our patient and could have led to earlier remission.

Clinical features of elderly-onset Adult-onset Still's disease

OBJECTIVES

To clarify the characteristics of patients with elderly-onset Adult-onset Still's disease (AOSD).

METHODS

Patients were classified into elderly-onset (>60 years: 47 patients) and younger-onset (≤60 years: 95 patients) groups according to their age at diagnosis of AOSD. Clinical features, treatments, and prognosis were compared between the elderly-onset and younger-onset groups.

RESULTS

In the elderly-onset group, compared with the younger-onset group, typical skin rashes were less frequent (21.3% vs 58.9%, respectively; p < .0001), whereas pleuritis (27.7% vs 7.4%, respectively; p = .0011) and disseminated intravascular coagulation (19.1% vs 2.1%, respectively; p = .0004) were more frequent, and serum ferritin levels were higher (median 12,700 ng/ml vs 2526 ng/ml, respectively; p < .0001). Overall survival and AOSD-related survival were reduced (p = .0006 and p = .0023, respectively) and drug-free remission was less frequent (p = .0035) in the elderly-onset group compared with the younger-onset group.

CONCLUSIONS

Our results demonstrated that elderly-onset AOSD patients had several characteristics that differed from younger-onset AOSD patients, including less typical skin lesions, more AOSD-related complications, higher ferritin levels, and poorer prognoses.

Clinical characteristics and comorbidities in adult-onset Still's disease using a large US administrative claims database

OBJECTIVES

We aimed to describe clinical characteristics, treatment patterns and major comorbidities of a US-based adult-onset Still's disease (AOSD) cohort.

METHODS

Administrative claims data from Truven MarketScan were collected from 2009 to 2015. An AOSD case was defined as ≥1 M06.1 International Classification of Diseases 10th revision (ICD-10) medical claim code. We extracted data for the AOSD cohort (n = 106) and 1:5 matched controls (n = 530) without AOSD. Outcomes of interest and a novel claims-based set of Yamaguchi criteria were identified by relevant ICD 9th revision (ICD-9) and ICD-10 codes. Bivariate descriptive analyses were conducted on all variables. Comorbidity rates and rate ratios were calculated in AOSD cases and matched controls. Statistical significance of cohort differences was determined to compare AOSD cases and matched controls.

RESULTS

The AOSD cohort, with a mean age of 43.08 (standard deviation, s.d. 13.9) years and with female predominance (68.9%) was observed over a mean of 750.12 (637.6) days. A total of 35.9% of AOSD patients fulfilled claims-based Yamaguchi criteria compared with 0.4% matched controls (P< 0.05). We identified severe AOSD-related complications, including macrophage activation syndrome (4.7%) and acute respiratory distress syndrome (12.3%). Treatment commonly involved systemic glucocorticoids (62.2%), MTX (51%) and anakinra (24.5%). Compared with matched controls, serious infections were significantly increased (rate ratio 2.58, 95% CI: 1.53, 4.37, P = 0.0004), while hyperlipidaemia (0.54, 95% CI: 0.35, 0.85; P = 0.008) and obesity (0.30, 95% CI: 0.15, 0.62; P = 0.001) were significantly decreased in AOSD patients.

CONCLUSION

We characterized a first US-based AOSD cohort using a large national administrative claims database, and identified key complications, treatments and comorbidities.

Targeting the Immune System for Pulmonary Inflammation and Cardiovascular Complications in COVID-19 Patients

In December 2019, following a cluster of pneumonia cases in China caused by a novel coronavirus (CoV), named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the infection disseminated worldwide and, on March 11th, 2020, the World Health Organization officially declared the pandemic of the relevant disease named coronavirus disease 2019 (COVID-19). In Europe, Italy was the first country facing a true health policy emergency, and, as at 6.00 p.m. on May 2nd, 2020, there have been more than 209,300 confirmed cases of COVID-19. Due to the increasing number of patients experiencing a severe outcome, global scientific efforts are ongoing to find the most appropriate treatment. The usefulness of specific anti-rheumatic drugs came out as a promising treatment option together with antiviral drugs, anticoagulants, and symptomatic and respiratory support. For this reason, we feel a duty to share our experience and our knowledge on the use of these drugs in the immune-rheumatologic field, providing in this review the rationale for their use in the COVID-19 pandemic.

Favorable Anakinra Responses in Severe Covid-19 Patients with Secondary Hemophagocytic Lymphohistiocytosis

Dysregulation of inflammation is hypothesized to play a crucial role in the severe complications of COVID-19, with the IL-1/IL-6 pathway being central. Here, we report on the treatment of eight severe COVID-19 pneumonia patients—seven hospitalized in intensive care units (ICUs) in Greece and one non-ICU patient in the Netherlands—with the interleukin-1 receptor antagonist Anakinra. All patients scored positive for the hemophagocytosis score (HScore) and were diagnosed with secondary hemophagocytic lymphohistocytosis (sHLH) characterized by pancytopenia, hyper-coagulation, acute kidney injury, and hepatobiliary dysfunction. At the end of treatment, ICU patients had less need for vasopressors, significantly improved respiratory function, and lower HScore. Although three patients died, the mortality was lower than historical series of patients with sHLH in sepsis. These data suggest that administration of Anakinra may be beneficial for treating severe COVID-19 patients with sHLH as determined by the HScore, and they support the need for larger clinical studies to validate this concept.

•

Anakinra treatment was administered to eight severe COVID-19 patients

•

All patients had secondary hemophagocytic lymphohistiocytosis

•

Respiratory function was improved at the end of treatment

•

In one patient, the need for mechanical ventilation was prevented

Elderly-onset Still's Disease Complicated by Macrophage Activation Syndrome: A Case Report and Review of the Literature

Adult-onset Still's disease (AOSD) usually affects young adults. Some cases of elderly-onset Still's disease (EOSD) have been reported, but its clinical features are unclear. We herein report a 74-year-old woman who developed AOSD with macrophage activation syndrome (MAS). We also reviewed 24 previous EOSD cases in patients over 70 years old and compared the findings with overall AOSD. While the clinical features were similar between the two, including the presence of MAS, disseminated intravascular coagulation was more frequent in EOSD than in AOSD. Furthermore, despite a similar frequency of glucocorticoid use, immunosuppressants and biologics were less frequently administered in EOSD than in AOSD. This report highlights the fact that typical AOSD can develop in elderly patients with some characteristic features.

Macrophage Activation Syndrome and Secondary Hemophagocytic Lymphohistiocytosis in Childhood Inflammatory Disorders: Diagnosis and Management

Macrophage activation syndrome (MAS), a form of secondary hemophagocytic lymphohistiocytosis, is a frequently fatal complication of a variety of pediatric inflammatory disorders. MAS has been most commonly associated with systemic juvenile idiopathic arthritis (sJIA), as approximately 10% of children with sJIA develop fulminant MAS, with another 30-40% exhibiting a more subclinical form of the disease. Children with other rheumatologic conditions such as systemic lupus erythematosus and Kawasaki disease are also at risk for MAS. Moreover, MAS also complicates various genetic autoinflammatory disorders such as gain of function mutations in the cytosolic inflammasome NLRC4, pediatric hematologic malignancies (e.g., T-cell lymphoma), and primary immunodeficiencies characterized by immune dysregulation. Disease-specific and broadly inclusive diagnostic criteria have been developed to facilitate the diagnosis of MAS. Recently, simple screening tools such as the serum ferritin to erythrocyte sedimentation rate ratio have been proposed. Early diagnosis and rapid initiation of immunosuppression are essential for the effective management of MAS. With a better understanding of the pathophysiology of MAS and the advent of novel therapeutics, a broad immunosuppressive approach to treatment is giving way to targeted anti-cytokine therapies. These treatments include agents that block interleukin-1 (IL-1), IL-6, IL-18, interferon-γ, as well as inhibitors of downstream targets of cytokine signaling (e.g., Janus kinases). Increased early recognition of MAS among pediatric inflammatory disorders combined with the use of effective and less toxic cytokine-targeted therapies should lower the mortality of this frequently fatal disorder.

[Adult-onset Still's disease complications]

Adult-onset Still's disease (AOSD), first described in 1971 by Bywaters, is a rare systemic auto-inflammatory disorder of unknown etiology, characterized by a symptomatic triad associating prolonged fever, polyarthritis and rash. The management of this disease has significantly improved since its first description, and, although the overall prognosis of the AOSD is good, with a low attributable mortality, below 3% (but up to 18% depending on the series), some rare complications are still possible, can be life-threatening and change the prognosis of the disease. A literature search was performed to review AOSD's complications: reactive hemophagocytic lymphohystiocytosis, coagulation disorders, fulminant hepatitis, cardiovascular (pericarditis, myocarditis, HTAP) or pulmonary complications, neurologic, renal complications, and AA amyloidosis. For most of AOSD-related complications, corticosteroids remain the first-line treatment, in association with supportive care measures in case of severe complications. In case of inadequate response, multidisciplinary care with concil from a referral center is advised, and IL-1 or IL-6 blockers, but also ciclosporine, are the molecule to use in second intention.

Management of adult-onset Still's disease with interleukin-1 inhibitors: evidence- and consensus-based statements by a panel of Italian experts

BACKGROUND

Adult-onset Still's disease (AOSD) is a rare inflammatory condition characterized by fever, rash, and arthritis. Because of its rarity, clinical trials are inherently small and often uncontrolled. Our objective was to develop recommendations for the use of interleukin (IL)-1 inhibitors in the management of patients with AOSD, based on the best evidence and expert opinion.

METHODS

A panel of 10 experts (9 rheumatologists and 1 pediatrician) was established. The first step was dedicated to a comprehensive literature review and development of statements. Two separate literature searches were performed on the MEDLINE (Pubmed), EMBASE, and BIOSIS databases through April 2018 to identify (1) differences and similarities between AOSD and pediatric Still's disease (systemic juvenile idiopathic arthritis [SJIA]) and (2) the efficacy and safety of IL-1 inhibitors in AOSD treatment. In the second step, the statements were submitted in a Delphi process to a panel of 67 rheumatologists. Consensus threshold was set at 66%: positive, > 66% of voters selected scores 3 to 5; negative, > 66% of voters selected scores 1 or 2. In the third step, the voting results were analyzed, and the statements were finalized.

RESULTS

Eleven statements were developed. Forty-six of 67 rheumatologists (72%) participated in the Delphi process. A positive consensus was reached after the first round of voting and was full (> 95%) on the majority of statements. A large consensus was achieved in considering AOSD and SJIA as the same disease. The use of anti-IL-1 therapies in refractory patients was considered quite safe and effective both as the first and as a subsequent line of biologic treatment, especially in systemic patients. Because of the lack of head-to-head comparisons, a different profile of efficacy among IL-1 inhibitors could not be established. There was a large consensus that failure of the first IL-1 inhibitor does not preclude response to another one. The lack of studies comparing early versus late treatment did not allow to draw conclusions; however, data from SJIA suggest a better response in early treatment.

CONCLUSIONS

The Delphi method was used to develop recommendations that we hope will help clinicians in the management of patients with AOSD refractory to conventional therapies.

Challenges in the diagnosis of hemophagocytic lymphohistiocytosis: Recommendations from the North American Consortium for Histiocytosis (NACHO)

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of pathologic immune activation, often associated with genetic defects of lymphocyte cytotoxicity. Though a distinctive constellation of features has been described for HLH, diagnosis remains challenging as patients have diverse presentations associated with a variety of triggers. We propose two concepts to clarify how HLH is diagnosed and treated: within the broader syndrome of HLH, "HLH disease" should be distinguished from "HLH disease mimics" and HLH subtypes should be categorized by specific etiologic associations, not the ambiguous dichotomy of "primary" and "secondary." We provide expert-based advice regarding the diagnosis and initiation of treatment for patients with HLH, rooted in improved understanding of its pathophysiology.

Macrophage activation syndrome complicating rheumatic diseases in adults: case-based review

Macrophage activation syndrome (MAS) is a life-threatening complication of rheumatologic diseases. Data regarding the clinical course, management and outcome of adults with MAS is limited. Therefore, we aimed to describe the clinical features, treatment and outcome of adult patients with MAS, and review the literature for previous cohorts. We retrospectively reviewed patients with MAS complicating rheumatologic diseases between the years 2007 and 2017. Through Pubmed, Medline and Scopus literature search we identified previous cases of adult patients with MAS. We identified 7 patients with MAS complicating rheumatologic diseases (5 females and 2 males). The median age of diagnosis was 32 (range 26-57) years. The median follow-up was 30 months (range 6.95-36.5) months. The underlying rheumatologic disease was adult onset Still's disease (AOSD) in 3 patients, systemic juvenile idiopathic arthritis (sJIA) in 2 patients, systemic lupus erythematosus (SLE) in 1 patient, and systemic vasculitis in 1 patient. Four patients developed MAS concurrently with the clinical development of the rheumatologic disease. All the patients were treated with systemic corticosteroids. Five patients were treated with cyclosporine A, one of which received combination therapy with anakinra, and one received tocilizumab. Two patients deceased during the hospitalization. We identified 92 patients from literature cohorts, 73 (79%) of them with AOSD. MAS developed concurrently with the underlying rheumatologic disease in 25 (27%) patients, and 30 (33%) patients deceased. Our cohort and previous cohorts demostrate that MAS often presents concurrently with the underlying rheumatologic disease and is associated with a high mortality rate. Further larger prospective studies are needed to determine the optimal management of MAS.

Calm in the midst of cytokine storm: a collaborative approach to the diagnosis and treatment of hemophagocytic lymphohistiocytosis and macrophage activation syndrome

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) were historically thought to be distinct entities, often managed in isolation. In fact, these conditions are closely related. A collaborative approach, which incorporates expertise from subspecialties that previously treated HLH/MAS independently, is needed. We leveraged quality improvement (QI) techniques in the form of an Evidence-Based Guideline (EBG) to build consensus across disciplines on the diagnosis and treatment of HLH/MAS.

METHODS

A multidisciplinary work group was convened that met monthly to develop the HLH/MAS EBG. Literature review and expert opinion were used to develop a management strategy for HLH/MAS. The EBG was implemented, and quality metrics were selected to monitor outcomes.

RESULTS

An HLH/MAS clinical team was formed with representatives from subspecialties involved in the care of patients with HLH/MAS. Broad entry criteria for the HLH/MAS EBG were established and included fever and ferritin ≥500 ng/mL. The rheumatology team was identified as the "gate-keeper," charged with overseeing the diagnostic evaluation recommended in the EBG. First-line medications were recommended based on the acuity of illness and risk of concurrent infection. Quality metrics to be tracked prospectively based on time to initiation of treatment and clinical response were selected.

CONCLUSION

HLH/MAS are increasingly considered to be a spectrum of related conditions, and joint management across subspecialties could improve patient outcomes. Our experience in creating a multidisciplinary approach to HLH/MAS management can serve as a model for care at other institutions.

Pulmonary arterial hypertension in adult-onset Still's disease: A case series and systematic review of the literature

OBJECTIVE

To investigate the prevalence, clinical characteristics and prognosis of pulmonary arterial hypertension (PAH) in adult onset Still's disease (AOSD).

METHODS

We retrospectively reviewed all patients with AOSD diagnosed during a 33-year period in 2 referral tertiary care hospitals, selecting for analysis those who presented PAH confirmed as by right heart catheterization. A systematic review of the literature (PubMed 1990 to July 2018) was also performed, in order to determine the prognosis and the most appropriate treatment strategy for this complication.

RESULTS

The overall prevalence of PAH in our AOSD population was 4.8% (2/41). Including our 2 cases, 20 well-documented patients have been reported. PAH may complicate AOSD at any time during its course, and usually occurs in patients who have persistent and severe disease, with a considerable frequency (35%) of previous or concomitant severe clinical complications. In all cases, the etiology of pulmonary hypertension was a group 1 PAH based on the 2015 ESC/ERS guidelines. Most patients in this series had advanced WHO functional classes III-IV at the time of PAH diagnosis, reflecting an important diagnostic delay. Thirty-three percent of patients had a poor outcome despite the therapy, with a mortality rate that reached 22%. The therapeutic strategy that achieved the best results was the use of glucocorticoids, immunosuppression and PAH-specific vasodilator therapy.

CONCLUSION

HAP is an under-recognized complication of AOSD that should be kept in mind in the differential diagnosis of those patients who experience dyspnea on exertion or a decrease in exercise tolerance.

The rheumatology/hematology interface: CAPS and MAS diagnosis and management

Catastrophic antiphospholipid antibody syndrome (CAPS) and macrophage activation syndrome (MAS) are both life-threatening hematologic disorders that infrequently afflict patients with rheumatologic disease. CAPS is characterized by fulminant multiorgan damage related to small vessel thrombosis in the setting of persistent antiphospholipid antibodies. It can occur in patients with rheumatologic diseases such as systemic lupus erythematosus but can also affect patients who do not have rheumatologic disease. By contrast, the term MAS is applied when patients with rheumatologic disease develop hemophagocytic lymphohistiocytosis (HLH); therefore, patients with MAS have an underlying rheumatologic disease by definition. Similar to CAPS, HLH/MAS can have a fulminant presentation, but the pathogenesis and manifestations are different. In both CAPS and MAS, management generally includes but is not limited to immunosuppression with steroids. Fatalities are relatively common and morbidity is often significant. Early recognition of these disorders and initiation of timely treatment are important. More effective therapies for both syndromes are urgently needed.

Anakinra in Still's disease: a profile of its use

The EU indication for anakinra has been extended to include Still’s disease, a serious rare inflammatory disorder of unknown aetiology that comprises adult-onset Still’s disease (AOSD) and systemic juvenile idiopathic arthritis (SJIA). As activated interleukin-1 pathways are associated with the systemic manifestations of these disorders, targeted treatment with anakinra, an interleukin-1 inhibitor, has been investigated. Across clinical and real-world studies in patients with AOSD and SJIA, treatment with anakinra achieved clinical remission/response, provided rapid and sustained improvements in systemic and laboratory manifestations, and allowed the use of corticosteroid- and disease-modifying anti-rheumatic drugs (DMARD) to be reduced or discontinued. The safety profile of anakinra in the treatment of Still’s disease is consistent with that in its other approved indications.

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

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

Adding colchicine to immunosuppressive treatments; a potential option for biologics-refractory adult-onset Still's disease

Background

Adult-onset Still’s disease (AOSD) is a rare inflammatory disorder characterized by the classical triad of daily spiking fever, arthritis, and typical salmon-colored rash. Resistance to first-line corticosteroids and second-line disease modified anti-rheumatic-drugs defines refractory AOSD, which mostly includes the polycyclic or chronic courses of the disease. Anti-cytokine therapies are recommended in AOSD patients who are refractory to traditional treatments. This is the first report on the efficacy of colchicine in a patient with AOSD which was refractory to immunosuppressive treatments including biologics.

Case presentation

A 24-years Japanese female patient was referred to our hospital for the flare-up of AOSD under the combined treatments with steroid, immunosuppressants, and biologics. She was diagnosed with AOSD according to the Yamaguchi criteria, based on the presence of spiking fever, polyarthralgia, skin rash, and hyperferritinemia. Interleukin-6 or tumor necrosis factor-α blockade treatments were not effective, the oral administration of colchicine was stared under the immunosuppressive treatments with steroid and cyclosporine A (CyA). Colchicine treatment silenced the disease activity of AOSD. The dose of prednisolone was successfully tapered, and the elevated levels of C-reactive protein were normalized. Remission has been maintained for 13 months with the start of oral administration of colchicine.

Conclusion

We concluded that colchicine is an alternative treatment in patients with refractory AOSD, particularly in those with impaired therapeutic effects against anti-cytokines therapies.