Treatment of clinically amyopathic dermatomyositis in adults: a systematic review

Comparison of characteristics and anti-MDA5 antibody distribution and effect between clinically amyopathic dermatomyositis and classic dermatomyositis: a retrospective case-control study

Background

Clinically amyopathic dermatomyositis (CADM) is a distinct subtype of dermatomyositis (DM) characterized by typical DM cutaneous findings but with minimal or no evidence of myositis. It possesses unique features different from classic DM (CDM). Anti-melanoma differentiation-associated gene 5 (MDA5) antibodies were found in CADM and are thought to increase the risk of rapidly progressive interstitial lung disease (RP-ILD) and are present in both CADM and CDM patients, affecting their condition and prognosis. Nevertheless, no large-sample studies have compared all aspects concerning patients with CADM and those with CDM. This study aimed to investigate differences in clinical characteristics and risk factors for mortality between CADM and CDM and to clarify the distribution and impact of anti-MDA5 antibodies in patients with these conditions.

Methods

A retrospective case-control study included 330 patients and collected and analyzed their clinical data from The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Hospital of Traditional Chinese Medicine between January 2015 and July 2022; all patients were followed up to evaluate changes in their condition and prognosis. Several new cohorts were designed around anti-MDA5 antibodies to explore their distribution and impact in CADM and CDM.

Results

We found CADM to be associated with higher rates of mortality, 1-year mortality, interstitial lung disease (ILD), and RP-ILD than CDM. In CADM, RP-ILD, anti-MDA5 antibodies, and high ferritin and lactate dehydrogenase (LDH) levels were identified as independent risk factors for death. In CDM, the neutrophil-to-lymphocyte ratio, anti-MDA5 antibodies, and high ferritin levels were shown to be independent risk factors for death, whereas mechanic's hand was considered a protective factor against it. Anti-MDA5 antibody-positive patients did not exhibit any significant difference based on whether they belonged to the CADM or CDM groups. When no anti-MDA5 antibody-positive patients participated, the ferritin levels and rates of RP-ILD and ILD were still higher in CADM than in CDM; however, such differences decreased, whereas the LDH levels, rates of mortality, and 1-year mortality did not differ. Anti-MDA5 antibody-positive patients consistently showed higher LDH and ferritin levels, lower lymphocyte levels, higher probability of RP-ILD and ILD, and worse prognosis than anti-MDA5 antibody-negative patients, irrespective of whether the patients had DM, CADM, or CDM.

Conclusion

Patients with CADM exhibit relatively worse symptoms, serological findings, and prognosis than those with CDM. Furthermore, patients with CADM and those with CDM have commonalities and differences in risk factors for death. Moreover, CADM may necessitate earlier and more aggressive treatment strategies than CDM. Anti-MDA5 antibodies occur at a high level in patients with CADM, not only affecting the symptoms and prognosis of DM but also having a non-negligible impact on the differences between CADM and CDM. Hence, screening for anti-MDA5 antibodies in patients with CADM and CDM is extremely essential.

Clinical Characteristics of Dermatomyositis with Interstitial Lung Disease: A Retrospective Case-Control Study

INTRODUCTION

Interstitial lung disease (ILD) is a common complication of dermatomyositis (DM) and one of the main risk factors for poor prognosis in DM patients. The aim of this study was to reveal the clinical characteristics of DM patients with ILD.

METHODS

Clinical data from the Second Affiliated Hospital of Soochow University were used to conduct a retrospective case-control study. Univariate and multivariate logistic regression analysis were performed to identify risk factors for ILD in DM.

RESULTS

A total of 78 DM patients were included in this study, including 38 DM patients with ILD and 40 DM patients without ILD. Compared with patients without ILD, patients with ILD were older (59.6 vs. 51.2 years, P = 0.004), and had higher rates of clinically amyopathic DM (CADM) (45 vs. 20%, P = 0.019), Gottron's papules (76 vs. 53%, P = 0.028), mechanic's hands (13 vs. 0%, P = 0.018), myocardial involvement (29 vs. 8%, P = 0.014), and higher positive rates of anti-SSA/Ro52 (74 vs. 20%, P < 0.001) and anti-melanoma differentiation-associated gene-5 (MDA5) (24 vs. 8%, P = 0.048) antibodies, while albumin (ALB) (34.5 vs. 38.0 g/l, P = 0.006), prognostic nutritional index (PNI) (40.3 vs. 44.7, P = 0.013), the rates of muscle weakness (45 vs. 73%, P = 0.013) and heliotrope rash (50 vs. 80%, P = 0.005) were lower. In addition, the five patients who died were all DM patients with ILD (13 vs. 0%, P = 0.018). Multivariate logistic regression showed that old age (odds ratio [OR] = 1.119, 95% confidence interval [CI] = 1.028-1.217, P = 0.009), Gottron's papules (OR = 8.302, 95% CI = 1.275-54.064, P = 0.027) and anti-SSA/Ro52 (OR = 24.320, 95% CI = 4.102-144.204, P < 0.001) were independent risk factors for ILD in DM.

CONCLUSIONS

DM patients with ILD usually present with older age, higher rates of CADM, Gottron's papules, mechanic's hands, myocardial involvement, higher positive rates of anti-MDA5 and anti-SSA/Ro52 antibodies, lower ALB, PNI, and lower rates of muscle weakness and heliotrope rash. Old age, Gottron's papules, and anti-SSA/Ro52 were independent risk factors for ILD in DM.

Adult and juvenile dermatomyositis treatment

INTRODUCTION

Dermatomyositis is a rare autoimmune inflammatory condition affecting skin and muscles. The disease can be seen in both adults and children. It can be associated with malignancy. Considering involvement of skin in the disease, many patients consult dermatologists for its treatment. Hence, knowledge about its presentation, complications, prognosis, and treatment is necessary.

OBJECTIVE

The objective of this review article is to provide comprehensive information about treatment of dermatomyositis.

METHODS

In this review article, we reviewed the published literature on adult and juvenile dermatomyositis to highlight the treatment. Articles published in peer-reviewed journals including reviews, clinical trials, case series, and case reports published in electronic database (MEDLINE/PubMed) through January 2021, cross references of respective articles and trials from clinicaltrials.gov were included for qualitative analysis of the literature.

RESULTS

Treatment options for dermatomyositis include traditional immunosuppressive agents and immunomodulatory therapy. High-dose corticosteroids represent the first line of treatment while other immunosuppressive agents are also used, either in combination with or as an alternative to corticosteroids, after initial treatment failure. Some biological agents have been used for the treatment of dermatomyositis with variable responses.

CONCLUSION

Although several treatment options are available, several questions remain unanswered about the optimal treatment of dermatomyositis.

The associations between myositis autoantibodies and clinical presentations in dermatomyositis

BACKGROUND

The myositis autoantibodies have been widely used clinically in recent years for the identification of an autoantibody-associated clinical phenotype in dermatomyositis (DM) patients. However, correlations between myositis autoantibodies and clinical presentations in different populations are lacking, especially in Taiwan.

OBJECTIVES

To investigate the correlations among cutaneous manifestations, myositis autoantibodies, and systemic diseases, including interstitial lung disease (ILD) and internal malignancy.

METHODS

A retrospective study of patients with histopathologically confirmed cutaneous manifestations of DM was conducted during 2005 to 2020 in Taiwan. A commercial line blot immunoassay technique was used to detect myositis autoantibodies.

RESULTS

A total of 88 DM patients were enrolled, with a mean age of onset of 49.4 years old. The most common systemic features were myositis (56.8%, 50/88), internal malignancy (22.7%, 20/88), dysphagia (19.3%, 17/88), and ILD (17%, 15/88). Among the enrolled patients, 32 patients received serum myositis autoantibodies examination. The most common autoantibodies were ANA (50.7%, 37/73), followed by anti-TIF1-γ (34.4%, 11/32) and anti-MDA5 (31.3%, 10/32) antibodies. Patients with Gottron sign (OR 5.6), arthritis (OR 23.35), or the presence of anti-MDA5 antibody (OR 11.14) were more susceptible to progressing to ILD, whereas patients with pruritus (OR 1.04), dysphagia (OR 6.73), and the presence of ANA (OR 6.29) had significantly higher risks of developing internal malignancies.

CONCLUSIONS

Physicians should pay special attention to certain clinical features, which can help with the early detection of systemic diseases. Cancer screening and myositis autoantibodies examination should be conducted in all DM patients if applicable.

Emerging Therapeutics in the Management of Connective Tissue Disease. Part II. Dermatomyositis and Scleroderma

The management of connective tissue diseases is dramatically evolving with the advent of biologics and novel oral systemic therapeutics. Despite involvement in the care of these complex patients, there is a knowledge gap in the field of dermatology regarding these emerging agents. The second article in this continuing medical education series discusses new and emerging therapeutics for dermatomyositis and scleroderma that target cells, intracellular signaling pathways, and cytokines.

Clinical Characteristics and Management of Patients With Clinical Amyopathic Dermatomyositis: A Retrospective Study of 64 Patients at a Tertiary Dermatology Department

Background: Clinical amyopathic dermatomyositis (CADM) represents a subtype of 5–20% of patients with dermatomyositis (DM), which can be categorized into amyopathic dermatomyositis (ADM) and hypomyopathic dermatomyositis (HDM). The characteristics of patients with CADM are still limited in English literature.

Objective: To investigate clinical features, cutaneous findings, diagnostic accuracy, and treatment regimen of CADM patients.

Methods: Sixty-four patients diagnosed with CADM at Peking Union Medical College Hospital by dermatologists were retrospectively analyzed. Data were recorded in the electronic database at each offline clinical consultation and directly extracted from medical records. 2017 EULAR/ACR criteria for idiopathic inflammatory myositis (IIM) classification was used to identify and classify patients with CADM. Published studies were searched to extract relevant data of CADM patients.

Results: This cohort included 38 ADM patients and 26 HDM patients. 2017 EULAR/ACR criteria classified 67.2% of patients with CADM into probable or definite DM. Antimalarials were given to a majority of CADM patients (72.6%, n = 45). However, 68.8% (31 out of 45) required at least one aggressive agent combined with hydroxychloroquine due to insufficient response or side effects. The median of systemic treatments in HDM was significantly higher than ADM (p = 0.007). The number of ADM patients using antimalarials as monotherapy was significantly higher than that of HDM patients (p = 0.031), while the number of HDM patients receiving steroids combined with immunosuppressants was significantly higher (p = 0.025). The median of Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) score improvement was 11.5 and 10.5 for ADM and HDM after a median follow-up of 31.5 and 32.5 months, respectively. Six patients with normal muscle strength developed muscle weakness after a median of 10.5 months (IQR 9-13), and elevated inflammatory markers at initial visit might indicate their muscle weakness development.

Conclusions: 32.8% of patients may be overlooked using the three skin variables of 2017 EULAR/ACR criteria. The response rate to single hydroxychloroquine in our cohort was 68.8%. Detailed treatment modalities were different among ADM and HDM. Long-term monitoring for the development of myositis in patients with CADM, especially those with elevated inflammatory markers at initial visit, may be warranted.

Assessing the compliance of systematic review articles published in leading dermatology journals with the PRISMA statement guidelines: A systematic review

Background

Reporting quality of systematic reviews and meta-analyses is of critical importance in dermatology because of their key role in informing health care decisions.

Objective

To assess the compliance of systematic reviews and meta-analyses in leading dermatology journals with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement guidelines.

Methods

This review was carried out in accordance with PRISMA guidelines. Included studies were reviews published across 6 years in the top 4 highest-impact-factor dermatology journals of 2017. Records and full texts were screened independently. Data analysis was conducted with univariate multivariable linear regression. The primary outcome was to assess the compliance of systematic reviews and meta-analyses in leading dermatology journals with the PRISMA statement.

Results

A total of 166 studies were included and mean PRISMA compliance across all articles was 73%. Compliance significantly improved over time (β = .016; P = <.001). The worst reported checklist item was item 5 (reporting on protocol existence), with a compliance of 15% of articles.

Conclusion

PRISMA compliance within leading dermatology journals could be improved; however, it is steadily improving.

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.

Case Report: Rapidly Progressive Interstitial Lung Disease in A Pregnant Patient With Anti-Melanoma Differentiation-Associated Gene 5 Antibody-Positive Dermatomyositis

Dermatomyositis occurs extremely rarely during pregnancy. A number of studies in the published literature have documented how the outcome of pregnancy is poor for both mother and fetus. The present case study reports on a patient who was diagnosed with clinically amyopathic dermatomyositis complicated by interstitial lung disease during pregnancy, and was successfully treated with a combined immunosuppressant regimen. To the best of the authors' knowledge, this is the first case study detailing how a pregnant woman with clinically amyopathic dermatomyositis with positive anti-melanoma differentiation-associated gene 5 antibody achieved complete remission after early intervention of combined immunosuppressive therapy without residual pulmonary interstitial changes.

Prevalence of interstitial lung disease in polymyositis and dermatomyositis: A meta-analysis from 2000 to 2020

OBJECTIVE

Interstitial lung disease (ILD) is the most important prognostic factor for mortality in patients with polymyositis (PM) and dermatomyositis (DM), but the prevalence of ILD in PM/DM may vary between countries. The aim of this study was to determine the overall prevalence of ILD in global patients with PM/DM.

METHODS

We performed a systematic literature review of studies published from Jan 1, 2000 to April 30, 2020 on ILD and PM/DM. We extracted data and pooled the prevalence by using a random-effect model due to high heterogeneity. Heterogeneity was assessed by subgroup analysis and sensitivity analysis.

RESULTS

A total of 34 studies with 10,130 patients were included in our meta-analysis. Pooled data demonstrated that the global prevalence of ILD in patients with PM/DM was 0.41 (95% confidence interval [CI] 0.35-0.48). However, this prevalence varied with geographical locations and time trends. The prevalence of ILD in PM/DM was 0.5 (95% CI 0.42-0.57) in Asia, 0.23 (95% CI 0.15-0.31) in America, and 0.26 (95% CI 0.18-0.34) in Europe. A higher prevalence of ILD was reported in studies published in 2011-2015 (0.43, 95% CI 0.34-0.52) and 2016-2020 (0.45, 95% CI 0.35-0.54), compared with those published in 2000-2010 (0.27, 95% CI 0.16-0.39). The pooled prevalence of ILD in patients with DM, PM, and clinically amyopathic dermatomyositis subtype was 0.42 (95% CI 0.35-0.49), 0.35 (95% CI 0.27-0.42), and 0.53 (95% CI 0.32-0.74), respectively. Patients with anti-Jo-1 and anti-melanoma differentiation-associated gene 5 antibodies were more likely to develop ILD than other myositis-specific autoantibodies.

CONCLUSION

The global prevalence of ILD in patients with PM/DM was approximately 41% and the condition was predominant in Asians. This highlights potential genetic and environmental differences in the pathogenesis of ILD in patients with PM/DM. More studies are required to elucidate the specific associations.

Anti-MDA-5 antibody-positive clinically amyopathic dermatomyositis with rapidly progressive interstitial lung disease treated with therapeutic plasma exchange: A case series

We present six cases of antimelanoma differentiation-associated gene 5 antibody (anti-MDA5-Ab)-positive clinically amyopathic dermatomyositis (CADM) with rapidly progressive interstitial lung disease (RP-ILD), which is known to have a poor prognosis. The outcomes of these cases are described after treatment with therapeutic plasma exchange (TPE). Clinical and therapeutic data for patients with CADM with RP-ILD were collected retrospectively from medical records. All six patients received early intensive care including high-dose corticosteroids, intravenous cyclophosphamide, and a calcineurin inhibitor, but lung disease and hypoxia became more severe. TPE was performed over a median of 9.5 sessions (range 3-14) per patient, and the median duration from admission to TPE was 23 days. Three patients received combined direct hemoperfusion using a polymyxin B-immobilized fiber column (PMX-DHP) therapy on successive days to manage acute respiratory failure. Four patients survived and two died due to respiratory failure. In the survival cases, ferritin decreased, and ferritin and KL-6 were lower at diagnosis. The patients who died had a higher alveolar-arterial oxygen difference and more severe lung lesions at the time of initiation of TPE. These findings indicate that a combination of conventional therapy and TPE may be useful for improvement of the prognosis of CADM with RP-ILD at the early stage of onset.

Dermatomyositis: An Update on Diagnosis and Treatment

Dermatomyositis is a rare inflammatory disease with characteristic cutaneous findings and varying amounts of systemic involvement. Patients may present with skin disease alone, have concomitant muscle disease, or have extracutaneous manifestations such as pulmonary disease or an associated malignancy. Given such diverse presentations, dermatomyositis is both a diagnostic and therapeutic challenge. However, a prompt diagnosis is of utmost importance to institute adequate therapy and screen patients for an associated malignancy. Dermatologists should play a crucial role in the diagnosis and management of patients with dermatomyositis as cutaneous disease tends to be chronic, negatively impact quality of life, and be more recalcitrant to therapy. In this review, we discuss diagnosis, with a focus on myositis-specific antibodies and their associated phenotypes. We also review therapies available for this often refractory skin disease.

Anti-MDA5 Antibody-positive Clinically Amyopathic Dermatomyositis Complicated by Unilateral Right-sided Interstitial Lung Disease

We herein report a case of anti-MDA5 antibody-positive, clinically amyopathic dermatomyositis complicated by unilateral interstitial lung disease (ILD) in a 78-year-old man with a history of left lung tumor resection. He was admitted due to a persistent fever and abnormal right pulmonary opacity. A transbronchial lung cryobiopsy revealed pulmonary fibrosis, and combined immunosuppressive therapy was initiated. Findings from multiple evaluations, including dynamic breathing magnetic resonance imaging, supported decreased perfusion, ventilation, and mobility of the left lung as etiological factors of unilateral lung ILD. When patients present with laterality of such findings, clinicians should be aware that atypical imaging findings may be observed.

Recent Advances in Pharmacological Treatments of Adult Dermatomyositis

PURPOSE OF THE REVIEW

Dermatomyositis (DM) is an uncommon autoimmune disease that primarily affects the skin, muscle, and/or lungs, and remains a therapeutic challenge. We discuss recent studies evaluating efficacy of conventional treatments for clinically amyopathic DM (CADM), DM-associated interstitial lung (ILD) disease, and classic DM (CDM). We highlight several emerging new therapies with a focus on clinical trials, systematic reviews, and case series in the last 5 years.

RECENT FINDINGS

Recent studies report a significant number of patients remain refractory to antimalarials and require second- and third-line agents. Effective treatment for DM-associated ILD can vary based on patient specific antibodies. CDM requires oral glucocorticoids; recent studies have evaluated the benefits of adjunctive therapies including methotrexate and calcineurin inhibitors. New therapies target cell populations or cytokines thought to drive disease pathogenesis. Dermatomyositis is an autoimmune disease that remains challenging to treat. Many patients are refractory to conventional therapies, warranting the development and evaluation of new treatments.

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.

Clinically Amyopathic Dermatomyositis Caused by a Tattoo

Introduction

Clinically amyopathic dermatomyositis (CADM) is a rare disease with unknown origin. It is characterized by the specific skin lesions of dermatomyositis (DM) without clinical or laboratory evidence of myopathy. Previous studies indicated that tattoo may induce immune response.

Case Report

A 22-year-old male who tattooed butterfly on the left chest with blue and red ink. Then, he gradually had typical Gottron rash and interstitial lung disease (ILD) without weakness of the muscle. The clinical presentation and laboratory test represent the diagnosis of CADM. According to the history, CADM was induced by the tattoo five months before admission.

Discussion

We first reported the CADM induced by a tattoo. However, further studies are still needed to approach the specific substances within the tattoo that trigger immune response.

Dermatology and Immunoglobulin Therapy: Who to Treat and How to Administer Immunoglobulins

Intravenous immunoglobulin (IVIG) replacement therapy has been used in immune deficiency diseases for more than 50 years. The indications for this treatment have evolved, however, and IVIG therapy is now used in various diseases in which the immune system plays a prominent role. IVIG therapy has carved out a niche in dermatology for the treatment of such conditions as dermatomyositis, autoimmune bullous diseases, and toxic epidermal necrolysis. Special attention has been paid to this therapy in recent years. New guidelines have been published and should be taken into consideration in dermatology. This review provides a practical guide to IVIG use in our specialty.

MDA5 autoantibody-another indicator of clinical diversity in dermatomyositis

Allenbach and colleagues have recently reported for the first time the results of an intriguing study of the histopathologic, immunopathologic and gene expression differences in muscle biopsy tissue from adult dermatomyositis (DM) patients who do and do not have circulating MDA5 autoantibodies (anti-MDA5). Anti-MDA5 were originally identified in a clinically-defined subset of DM patients whose disease was expressed predominately in the skin for unusually long periods of time without accompanying muscle weakness [i.e., "clinically-amyopathic DM" (CADM)] and were at risk for acute, rapidly-progressive form of interstitial lung disease (ILD). As an academic dermatologist in the United States of America (USA) having a career-long interest in the CADM subset, I would like to share my perspective on the results of the work by Allenbach and colleagues and offer some suggestions for additional study in this area. But to do so most effectively, I first would like to review the clinical concept of CADM and its association with anti-MDA5 antibody production and a potentially-fatal form of (ILD).