Short-term, low-dose etoposide in refractory adult-onset Still's disease-associated macrophage activation syndrome

Management of adult-onset Still's disease: evidence- and consensus-based recommendations by experts

OBJECTIVES

Adult-onset Still's disease (AOSD) is a rare condition characterized by fevers, rash, and arthralgia/arthritis; most doctors treating AOSD in the Netherlands treat <5 patients per year. Currently, there is no internationally accepted treatment guideline for AOSD. The objectives of this study were to conduct a Delphi panel aimed at reaching consensus about diagnostic and treatment strategies for patients with AOSD and to use the outcomes as a basis for a treatment algorithm.

METHODS

The Delphi panel brought together 18 AOSD experts: rheumatologists, internists and paediatricians. The Delphi process consisted of three rounds. In the first two rounds, online lists of questions and statements were completed. In the third round, final statements were discussed during a virtual meeting and a final vote took place. Consensus threshold was set at 80%. Two targeted literature searches were performed identifying the level of evidence of the consensus-based statements.

RESULTS

Consensus was reached on 29 statements, including statements related to diagnosis and diagnostic tests, definition of response and remission, the therapy, the use of methotrexate and tapering of treatment. The panel consented on reduction of the use of glucocorticoids to avoid side effects, and preferred the use of biologics over conventional treatment. The role of IL-1 and IL-6 blocking agents was considered important in the treatment of AOSD.

CONCLUSION

In this Delphi panel, a high level of consensus was achieved on recommendations for diagnosis and therapy of AOSD that can serve as a basis for a treatment guideline.

Unveiling the Mystery of Adult-Onset Still's Disease: A Compelling Case Report

Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disorder. Diagnosis can take a long time, especially in the presence of confounding factors, and it is, to some extent, a process of exclusion. AOSD has life-threating complications ranging from asymptomatic to severe, such as macrophage activation syndrome (MAS), which is also referred to as hemophagocytic lymphohistocytosis (HLH). This condition is correlated with cytokine storm production and monocyte/macrophage overactivation and typically occurs with rash, pyrexia, pancytopenia, hepatosplenomegaly and systemic involvement. Exitus occurs in approximately 10% of cases. For the treatment of MAS-HLH, the Histiocyte Society currently suggests high-dose corticosteroids, with the possible addition of cyclosporine A, anti-interleukin (IL)-1, or IL-6 biological drugs; the inclusion of etoposide is recommended for the most severe conditions. In all cases, a multidisciplinary collaboration involving the resources and expertise of several specialists (e.g., rheumatologist, infectiologist, critical care medicine specialist) is advised. Herein, we provide a detailed description of the clinical case of a previously healthy young woman in which MAS developed as a dramatic onset manifestation of AOSD and whose diagnosis posed a real clinical challenge; the condition was finally resolved by applying the HLH-94 protocol (i.e., etoposide in combination with dexamethasone).

Advances in attractive therapeutic approach for macrophage activation syndrome in COVID-19

Nowadays, people have relaxed their vigilance against COVID-19 due to its declining infection numbers and attenuated virulence. However, COVID-19 still needs to be concern due to its emerging variants, the relaxation of restrictions as well as breakthrough infections. During the period of the COVID-19 infection, the imbalanced and hyper-responsive immune system plays a critical role in its pathogenesis. Macrophage Activation Syndrome (MAS) is a fatal complication of immune system disease, which is caused by the excessive activation and proliferation of macrophages and cytotoxic T cells (CTL). COVID-19-related hyperinflammation shares common clinical features with the above MAS symptoms, such as hypercytokinemia, hyperferritinemia, and coagulopathy. In MAS, immune exhaustion or defective anti-viral responses leads to the inadequate cytolytic capacity of CTL which contributes to prolonged interaction between CTL, APCs and macrophages. It is possible that the same process also occurred in COVID-19 patients, and further led to a cytokine storm confined to the lungs. It is associated with the poor prognosis of severe patients such as multiple organ failure and even death. The main difference of cytokine storm is that in COVID-19 pneumonia is mainly the specific damage of the lung, while in MAS is easy to develop into a systemic. The attractive therapeutic approach to prevent MAS in COVID-19 mainly includes antiviral, antibiotics, convalescent plasma (CP) therapy and hemadsorption, extensive immunosuppressive agents, and cytokine-targeted therapies. Here, we discuss the role of the therapeutic approaches mentioned above in the two diseases. And we found that the treatment effect of the same therapeutic approach is different.

Etoposide: A rider on the cytokine storm

For more than 40 years, the epipodophyllotoxin drug etoposide is prescribed to treat cancer. This semi-synthetic compound remains extensively used to treat advanced small-cell lung cancer and in various chemotherapy regimen for autologous stem cell transplantation, and other anticancer protocols. Etoposide is a potent topoisomerase II poison, causing double-stranded DNA breaks which lead to cell death if they are not repaired. It is also a genotoxic compound, responsible for severe side effects and secondary leukemia occasionally. Beyond its well-recognized function as an inducer of cancer cell death (a "killer on the road"), etoposide is also useful to treat immune-mediated inflammatory diseases associated with a cytokine storm syndrome. The drug is essential to the treatment of hemophagocytic lymphohistiocytosis (HLH) and the macrophage activation syndrome (MAS), in combination with a corticosteroid and other drugs. The use of etoposide to treat HLH, either familial or secondary to a viral or parasitic infection, or treatment-induced HLH and MAS is reviewed here. Etoposide dampens inflammation in HLH patients via an inhibition of the production of pro-inflammatory mediators, such as IL-6, IL-10, IL-18, IFN-γ and TNF-α, and reduction of the secretion of the alarmin HMGB1. The modulation of cytokines production by etoposide contributes to deactivate T cells and to dampen the immune stimulation associated to the cytokine storm. This review discussed the clinical benefits and mechanism of action of etoposide (a "rider on the storm") in the context of immune-mediated inflammatory diseases, notably life-threatening HLH and MAS. The question arises as to whether the two faces of etoposide action can apply to other topoisomerase II inhibitors.

Rare complications of anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis: Time to nip them in the bud

Anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis (MDA5+ DM) is an infrequent autoimmune disease, which mainly distributes in Asians and females. MDA5+ DM usually presents various skin lesions and positive anti-MDA5 antibody (a myositis-specific autoantibody for itself) with amyopathic or hypomyopathic features. For MDA5+ DM patients, rapidly progressive interstitial lung disease is a common complication with a high-speed deterioration and a poor prognosis. Besides, there are other complications of MDA5+ DM patients, including pneumomediastinum, macrophage activation syndrome and spontaneous intramuscular hemorrhage. These complications were rare but lethal, so it is necessary to explore their diagnosis methods, therapies and potential mechanisms, which are helpful for early diagnoses and timely treatment. To date, several cases and studies have shown distinctive features, diagnoses and treatments of these three rare complications, and there are also some differences among them. In this review, we outlined the characteristics, administration and potential pathogenesis of these rare complications of MDA5+ DM.

Perspectives on the use of non-biological pharmacotherapy for adult-onset Still's disease

INTRODUCTION

The treatment of the patients with adult-onset Still's disease (AOSD) remains largely empirical and it is based on the administration of immunosuppressive drugs. In this work, we described the use of non-biological pharmacotherapies for AOSD.

AREA COVERED

Although nonsteroidal anti-inflammatory drugs (NSAIDs) are employed during the diagnostic phase, glucocorticoids (GCs) are the first-line therapy, administered at the beginning of the disease. As second-line therapy, conventional synthetic disease modifying anti-rheumatic drugs (csDMARDs) are used when GCs do not fully control the disease and/or to reduce the dosage of concomitant GCs. Methotrexate (MTX) is the most commonly administered csDMARDs whereas calcineurin inhibitors (CNIs) are used in severe patients. The lack of achievement of clinical response may lead to the administration of biologic DMARDs, with or without csDMARDs.

EXPERT OPINION

The management of AOSD may benefit from the administration of non-biological pharmacotherapies, including GCs, MTX, and CNIs. These therapies showed efficacy in inducing a clinical response, in managing life-threatening complications, and may be well tolerated in combination with biologic DMARDs. However, further specific studies are needed to fully clarify the specific role of such drugs in clinical practice to improve the management of AOSD and to provide a more tailored treatment.