An Adolescent Case of Anti-MDA5 Antibody-Positive Juvenile Dermatomyositis With Interstitial Lung Disease Successfully Treated by Multitarget Therapy Avoiding Cyclophosphamide: A Case Report and Literature Review

Juvenile dermatomyositis (JDM) patients who test positive for the antimelanoma differentiation-associated gene 5 (MDA5) antibody have a poor prognosis because of rapidly progressing interstitial lung disease (ILD). However, agreement on the best treatment for this condition remains elusive. We encountered a 13-year-old girl with anti-MDA5 antibody-positive JDM who presented with arthritis and was already showing signs of ILD when she was admitted to the hospital. While cyclophosphamide (CY) is commonly used, it can cause gonadal disorders and other complications when administered to adolescent females. Consequently, we chose multitarget therapy, which includes tacrolimus and mycophenolate mofetil. Her ILD and skin symptoms gradually improved, and she was able to maintain remission and avoid CY administration for three years. We conducted a thorough literature review to determine the efficacy and safety of multitarget therapy for anti-MDA5 antibody-positive DM and JDM. Multitarget therapy shows promise as a potentially effective and relatively safe treatment. The ability to avoid CY, which is especially important for adolescent patients concerned about fertility preservation, highlights a significant benefit of this multitarget therapy for anti-MDA5 antibody-positive DM and JDM patients.

Single-cell profiling reveals distinct adaptive immune hallmarks in MDA5+ dermatomyositis with therapeutic implications

Anti-melanoma differentiation-associated gene 5-positive dermatomyositis (MDA5+ DM) is an autoimmune condition associated with rapidly progressive interstitial lung disease and high mortality. The aetiology and pathogenesis of MDA5+ DM are still largely unknown. Here we describe the immune signatures of MDA5+ DM via single-cell RNA sequencing, flow cytometry and multiplex immunohistochemistry in peripheral B and T cells and in affected lung tissue samples from one patient. We find strong peripheral antibody-secreting cell and CD8+ T cell responses as cellular immune hallmarks, and over-stimulated type I interferon signaling and associated metabolic reprogramming as molecular immune signature in MDA5+ DM. High frequency of circulating ISG15+ CD8+ T cells at baseline predicts poor one-year survival in MDA5+ DM patients. In affected lungs, we find profuse immune cells infiltration, which likely contributes to the pro-fibrotic response via type I interferon production. The importance of type I interferons in MDA5+ DM pathology is further emphasized by our observation in a retrospective cohort of MDA5+ DM patients that combined calcineurin and Janus kinase inhibitor therapy show superior efficacy to calcineurin inhibitor monotherapy. In summary, this study reveals key immune-pathogenic features of MDA5+ DM and provides a potential basis for future tailored therapies.

Rituximab in the Treatment of Interstitial Lung Diseases Related to Anti-Melanoma Differentiation-Associated Gene 5 Dermatomyositis: A Systematic Review

Objective

The effectiveness of rituximab in anti-melanoma differentiation-associated gene 5 (MDA5) dermatomyositis (DM) with interstitial lung disease (ILD) has been explored only in isolated case reports and small series. This paper aims to review the current evidence regarding rituximab (RTX) use in the treatment of ILD related to anti-MDA5 DM (anti-MDA5 DM-ILD).

Methods

We conducted a review by searching PubMed, Web of Science, Embase, and Cochrane for articles with information on patients with anti-MDA5 DM and RTX treatment, published until August 2021, in English language. The selected studies listed variation in chest high-resolution computed tomography (HRCT) and/or pulmonary function test (PFT) as a primary outcome, in patients with anti-MDA5 DM-related ILD after using RTX.

Results

Of the 145 potentially eligible articles, 17 were selected. The information gathered from a total of 35 patients with anti-MDA5 DM-ILD was reviewed, including 13 men and 22 women. Patient age at onset was 47.60 ± 13.72 years old. A total of 11.43% (4/35) of the patients were found to have chronic ILD (C-ILD) and 88.57% (31/30) exhibited rapidly progressive ILD (RP-ILD). Most patients (29/30) had typical DM rashes. Prior to RTX administration, the majority of patients (27/35) were treated with medium- or high-dose glucocorticoids and at least one additional immunotherapeutic agent. With regard to RTX efficacy for ILD in anti-MDA5 DM, 71.43% (25/35) of the patients responded to treatment. Skin rash also improved in more than half of the patients after RTX treatment. The most common side effects were infections, reported by 37.14% (13/35) of the patients after using RTX.

Conclusion

As a CD20 targeting drug, RTX is a promising therapeutic tool for anti-MDA5 DM-ILD, although the risk of infections should be considered before treatment. Further prospective controlled studies are required to evaluate the optimal RTX treatment regimen.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021289714, identifier CRD42021289714.

Anti-MDA5 antibody-positive dermatomyositis with rapidly progressive interstitial lung disease: report of two cases

Melanoma differentiation-associated protein 5 (MDA5) antibody-positive dermatomyositis (DM) displays unique cutaneous and pathologic features. We describe two cases of myositis-associated rapidly progressive interstitial lung disease (RP-ILD). The patients were two women from Kerala, India. Both patients had anti-MDA5 antibody-positive myositis. Both patients presented with RP-ILD without any clinical features of myositis and succumbed to their illness despite aggressive medical treatment. Anti-MDA5-antibody-positive DM is characterised by amyopathic disease with rapidly progressive and fatal ILD.

Treatment challenges in clinically amyopathic dermatomyositis: A case series and review of new therapeutic options for skin involvement

The term clinically amyopathic dermatomyositis (CADM) is used to represent a subgroup of patients with the typical cutaneous features of dermatomyositis (DM) in the absence of muscle involvement. Similar to classic DM, CADM can be associated with other connective tissue disorders and systemic manifestations such as interstitial lung disease and malignancy. Owing to the frequent discordance between muscle response and skin disease, the therapeutic approach to CADM represents a challenge. The current literature suggests that CADM treatment should follow a specific protocol, influenced by visceral involvement and the expression of certain myositis-specific antibodies, and different from the recommendation in the presence of myositis. Here, we present five new cases of CADM. We describe the available therapeutic options for skin manifestations in this type of DM, and we propose a step-by-step therapeutic scheme, using the cutaneous dermatomyositis disease area and severity index to assess response. Our literature review establishes mycophenolate mofetil and intravenous immunoglobulin as the most frequently successful therapies in refractory skin disease.

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive dermatomyositis responds to rituximab therapy

OBJECTIVES

The purpose of this study was to assess the efficacy of rituximab (RTX) in the management of anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody-positive dermatomyositis (DM), with or without rapidly progressive interstitial lung disease (RP-ILD).

METHODS

Medical records of DM patients with anti-MDA5 antibodies treated with RTX therapy were reviewed retrospectively. Skin rash data, lung function tests, chest high-resolution computed tomography (HRCT), and serum markers were compared before and after RTX.

RESULTS

Eleven consecutive cases, including 5 males and 6 females, were identified. One hundred percent of patients had a typical DM rash and about 45% presented with skin ulceration. All the patients had ILD, 73% had RP-ILD, and 27% had mild or asymptomatic ILD. Ro-52 antibodies were found in 55% of this group. Lymphopenia was present in 10/11 patients (91%). Around half (55%) had a level of ferritin greater than 1000 ng/ml. Nine patients (82%) were refractory. These patients received intravenous RTX (375 mg/m²) at 0 and 14 days (conventional dose) or 100 mg once a week for 4 weeks (low dose). After RTX treatment, 2 patients (18%) with mild ILD showed complete remission, and 6 (55%) showed improvement in lung HRCT and/or lung function. Skin rash in 4 patients (100%) and ILD in 3 (75%) showed improvement in the low-dose group. Infection episodes occurred in four (57%) and one (25%) of the conventional-dose and low-dose group, respectively.

CONCLUSIONS

Our study found that RTX is sufficient to improve skin rash and ILD or RP-ILD. Our results also suggest that lower RTX doses may be a useful therapy for anti-MDA5 antibody-positive DM patients. Key Points • To clarify efficacy of RTX in the management of anti-MDA5 antibody-positive DM, we performed a retrospective chart review of DM patients with anti-MDA5 antibodies who were treated with RTX. • This study found that RTX is sufficient to improve skin rash and ILD or RP-ILD. • The results suggest that low-dose RTX in treatment of MDA5-DM results in better responses and fewer adverse events.

Recommendations for the treatment of anti-melanoma differentiation-associated gene 5-positive dermatomyositis-associated rapidly progressive interstitial lung disease

OBJECTIVES

The study aimed to develop evidence-based recommendations for the treatment of rapidly progressive interstitial lung disease (RPILD) associated with the anti-Melanoma Differentiation-Associated Gene 5-positive dermatomyositis (DM) syndrome.

METHODS

The task force comprised an expert panel of specialists in rheumatology, intensive care medicine, pulmonology, immunology, and internal medicine. The study was carried out in two phases: identifying key areas in the management of DM-RPILD syndrome and developing a set of recommendations based on a review of the available scientific evidence. Four specific questions focused on different treatment options were identified. Relevant publications in English, Spanish or French up to April 2018 were searched systematically for each topic using PubMed (MEDLINE), EMBASE, and Cochrane Library (Wiley Online). The experts used evidence obtained from these studies to develop recommendations.

RESULTS

A total of 134 studies met eligibility criteria and formed the evidentiary basis for the recommendations regarding immunosuppressive therapy and complementary treatments. Overall, there was general agreement on the initial use of combined immunosuppressive therapy. Combination of high-dose glucocorticoids and calcineurin antagonists with or without cyclophosphamide is the first choice. In the case of calcineurin antagonist contraindication or treatment failure, switching or adding other immunosuppressants may be individualized. Plasmapheresis, polymyxin B hemoperfusion and/or intravenous immunoglobulins may be used as rescue options. ECMO should be considered in life-threatening situations while waiting for a clinical response or as a bridge to lung transplant.

CONCLUSIONS

Thirteen recommendations regarding the treatment of the anti-MDA5 positive DM-RPILD were developed using research-based evidence and expert opinion.

Dermatomyositis: Diagnosis and treatment

The second article in this continuing medical education series reviews the initial evaluation of patients with suspected dermatomyositis (DM), the relevant work-up for malignancy and interstitial lung disease once a diagnosis of DM is made, and treatment recommendations for patients with DM based on disease severity, the presence of systemic symptoms, and myositis-specific antibody (MSA) profiles. This review emphasizes the emerging role of MSAs in the diagnosis of DM and highlights how MSAs can be used to guide the appropriate work-up for malignancy and interstitial lung disease. The treatment approach proposed by this continuing medical education series discusses both established and novel therapies for DM and highlights the importance of considering lesion type, degree of muscle involvement, presence of systemic symptoms, presence of MSAs, and patient age when determining the best treatment approach for a patient with DM.

Anti-MDA5 Antibody Spectrum in Western World

PURPOSE OF REVIEW

Anti-melanoma differentiation-associated gene 5 (anti-MDA5) is a novel and highly specific myositis-associated autoantibody, which defines a unique phenotype among patients with dermatomyositis (DM).

RECENT FINDINGS

Anti-MDA5 was originally characterized in Japan in DM patients with hallmark cutaneous features and no proximal muscle weakness and termed clinically amyopathic DM (CADM). Anti-MDA5 has characteristic cutaneous manifestations which include tender palmar papules and cutaneous ulcerations, along with an increased frequency of interstitial lung disease (ILD) that can be rapidly progressive (RPILD) and fatal. This review will highlight the clinical significance of anti-MDA5 autoantibodies in Caucasian DM patients.

Effective Administration of Rituximab in Anti-MDA5 Antibody-Positive Dermatomyositis with Rapidly Progressive Interstitial Lung Disease and Refractory Cutaneous Involvement: A Case Report and Literature Review

We describe the case of a 48-year-old man with dermatomyositis (DM) who demonstrated rapidly progressive interstitial lung disease (RP-ILD) and refractory cutaneous involvement together with high levels of anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5-Ab). Even after combination immunosuppressive therapy including a corticosteroid, cyclosporine A, and intravenous cyclophosphamide, his respiratory insufficiency and cutaneous involvement progressively worsened. However, the administration of rituximab (RTX) resulted in clinical remission as well as a visible reduction in anti-MDA5-Ab levels, suggesting that RTX could be a useful remedy in cases refractory to conventional immunosuppressive agents, especially those of RP-ILD related to anti-MDA5-Ab–positive DM.

Dermatomyositis with Rapidly Progressive Interstitial Lung Disease Treated with Rituximab: A Report of 3 Cases in Japan

We performed a retrospective chart review of three patients with hypomyopathic dermatomyositis and rapidly progressive interstitial lung disease. The patients were Japanese women of 71, 69, and 65 years of age. Two patients were anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody-positive and 1 was anti-aminoacyl-tRNA synthetase (anti-ARS) antibody-positive. Their respiratory statuses deteriorated despite the administration of glucocorticoid, calcineurin inhibitors, and intravenous cyclophosphamide therapy. We subsequently administered rituximab. The anti-ARS antibody-positive patient survived, while 2 anti-MDA5 antibody-positive patients died.

Rituximab in the treatment of inflammatory myopathies: a review

Several uncontrolled studies have encouraged the use of rituximab (RTX) in patients with myositis. Unfortunately, the first placebo-phase trial to assess the efficacy of RTX in refractory myositis did not show a significant difference between the two treatment groups, and doubts have been expressed about its study design. In this review we present an up-to-date overview of the reported experiences of RTX therapy in myositis. A PubMed search was performed to find all the available cases of refractory myositis patients treated with RTX up to July 2015. The following terms were assessed: inflammatory myopathies OR anti-synthetase syndrome OR polymyositis OR dermatomyositis AND RTX. A total of 48 studies were included. We identified 458 patients with myositis treated with RTX. We found a rate of response to RTX of 78.3%. RTX can play a role in the management of patients with myositis, at least in those with positive myositis-specific autoantibodies.

Increased Serum B Cell Activating Factor and a Proliferation-inducing Ligand Are Associated with Interstitial Lung Disease in Patients with Juvenile Dermatomyositis

OBJECTIVE

Rapidly progressive interstitial lung disease (RP-ILD) is an intractable and fatal complication of juvenile dermatomyositis (JDM). This study evaluated serum levels of B cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) in JDM patients with complicating ILD, and their association with ILD phenotypes, clinical variables, and anti-melanoma differentiation-associated gene 5 (MDA5).

METHODS

We measured the levels of BAFF, APRIL, and anti-MDA5 in the sera of 23 JDM patients with ILD [8 in the RP-ILD group and 15 in the chronic ILD (C-ILD) group], 17 JDM patients without ILD (non-ILD group), and 10 age-matched controls, using the ELISA method. ILD was identified by high-resolution computed tomography.

RESULTS

Serum BAFF titers were significantly higher in the JDM patients with RP-ILD versus those with C-ILD (p = 0.011) and in healthy controls (p = 0.0004). The C-ILD group had significantly higher levels of BAFF versus controls (p ≤ 0.0001). Serum APRIL was markedly elevated in the RP-ILD group as compared with the C-ILD group (p = 0.003) and controls (p = 0.006). In patients with ILD, both BAFF and APRIL levels were correlated with serum Krebs von den Lungen-6 and interleukin 18. Subjects with high titer anti-MDA5 (> 200 U) had higher levels of BAFF and APRIL than those with low titer anti-MDA5 (< 100 U; p = 0.019 and p = 0.0029, respectively), which may have been due to a relationship between RP-ILD and high anti-MDA5 titer.

CONCLUSION

Our findings of markedly elevated levels of BAFF and APRIL in patients with RP-ILD JDM suggest the potential importance of these cytokines in the diagnosis and treatment of RP-ILD accompanying JDM.

A case of anti-MDA5-positive rapidly progressive interstitial lung disease in a patient with clinically amyopathic dermatomyositis ameliorated by rituximab, in addition to standard immunosuppressive treatment

Rapidly progressive interstitial lung disease (RP-ILD) in patients with clinically amyopathic dermatomyositis (CADM) associated with antibodies to melanoma differentiation-associated gene5 (MDA5) results in a high mortality rate. We experienced a case of anti-MDA5-positive RP-ILD of CADM which showed a response to rituximab, although there was no significant effect due to standard immunosuppressive treatment. This case suggests that rituximab has the potential to offer an effective agent for the treatment of anti-MDA5-positive RP-ILD of CADM.

[Biological therapy in idiopathic inflammatory myopathies]

Idiopathic inflammatory myopathies are systemic, immune-mediated diseases characterized by proximal, symmetrical, progressive muscle weakness. The aim of this work is to give an overview of the biological therapy used in the treatment of idiopathic inflammatory myopathies. The authors also focus on novel results in the therapy directed against the B- and T-cells. They emphasize the importance of new trials in these diseases which may lead to the introduction of novel therapeutic options in these disorders.