IFN-γ: An overlooked cytokine in dermatomyositis with anti-MDA5 antibodies

Dermatomyositis with anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 DM) is a rare autoimmune disease, often complicated by life-threatening, rapidly progressive interstitial lung disease. Additional manifestations of the disease include skin lesions, vascular abnormalities, joints and muscles pain. Despite its clinical significance, the pathogenesis of anti-MDA5 DM remains largely unknown. Currently, the disease is perceived as driven by type I interferon (IFN) whose expression is increased in most of the patients. Importantly, the regulation of IFN-γ is also altered in anti-MDA5 DM as evidenced by the presence of IFN-γ positive histiocytes in the lungs of patients, and the identification of autoantibodies that directly stimulate the production of IFN-γ by mononuclear cells. This review critically examines the pathogenesis of the disease, shedding light on recent findings that emphasize a potential role of IFN-γ. A novel conceptual framework is proposed, which integrates the molecular mechanisms altering IFN-γ regulation in anti-MDA5 DM with the known functional effects of IFN-γ on key tissues affected during the disease, such as the lungs, skin, and vessels. Understanding the precise role and relevance of IFN-γ in the pathogenesis of the disease will not only enhance the selection of available therapies for anti-MDA5 DM patients but also pave the way for the development of new therapeutic approaches targeting the altered molecular pathways.

Anti-melanoma differentiation-associated gene 5 and anti-Ro52 antibody-dual positive dermatomyositis accompanied by rapidly lung disease: Three case reports

BACKGROUND

Clinically amyopathic deramatomyositis was manifested as the various cutaneous dermatomyositis (DM) manifestations without muscle weakness. Anti-melanoma differentiation-associated gene 5 (anti-MDA5) and anti-Ro52 antibody-dual positive clinically amyopathic DM patients are at a high risk of developing rapidly progressive interstitial lung disease, and they exhibit an immensely high half-year mortality.

CASE SUMMARY

We presented three patients with anti-MDA5 and anti-Ro52 antibody-dual positive DM patients and we reviewed the previous studies on the link between anti-MDA5 and anti-Ro52 antibody-dual positive DM. Although we aggressively treated these patients similarly, but they all exhibited different prognoses. We reviewed the importance of clinical cutaneous rashes as well as the pathogenesis and treatment in the dual positive anti-MDA5 and anti-Ro52 associated DM.

CONCLUSION

Patients with anti-MDA5 anti-Ro52 antibody-dual positive DM should be accurately diagnosed at an early stage and should be treated aggressively, thus, the patient's prognosis can be significantly modified.

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.

Four cases of dermatomyositis with abnormally high anti-MDA-5 antibody titres and not high levels of serum ferritin

Anti-melanoma differentiation-associated gene 5 (MDA-5) antibody-positive dermatomyositis is a fatal disease presenting with rapidly progressive interstitial lung disease. High ferritin levels are a well-known poor prognostic factor. A high anti-MDA-5 antibody titre was also recently identified as a poor prognostic factor. We encountered four cases that had extremely high anti-MDA-5 antibody titres without high levels of ferritin in the initial examination. All cases were female with ages ranging between 29 and 54 years (mean age, 44 years). In the initial examination, anti-MDA-5 antibody titres were 2060-3040 (normal range, <32 index), ferritin levels were 87-480 ng/ml (normal range, 2.6-129.4 ng/ml), KL-6 level was 186-1806 U/ml (normal range, <500 U/ml), and creatine kinase level was normal in all patients. One patient had respiratory distress on exertion. Computed Tomography (CT) images showed mild ground-glass attenuation/reticular shadows near the pleura in all patients. Three patients were treated with a combination of high-dose glucocorticoids, intermittent intravenous cyclophosphamide, and calcineurin inhibitors, and two required plasma exchange due to the worsening of lung lesion. In these patients, ferritin and KL-6 levels tended to elevate after the beginning of treatment. Very mild pulmonary lesions disappeared in one patient treated with moderate doses of a glucocorticoid and calcineurin inhibitor. All patients survived, and one required oxygen on exertion at discharge. The condition of patients with abnormally high anti-MDA-5 antibody titres may deteriorate even though ferritin levels were not high and lung shadows are minimal at presentation. Therefore, intensive treatment needs to be considered early in the course of the disease regardless of the serum ferritin level.

Cutaneous Features of Anti-MDA-5 Antibody-Positive Amyopathic Dermatomyositis in a Sudanese Patient

Clinically amyopathic dermatomyositis (CADM) is a rare form of DM characterized by unique cutaneous and pulmonary features with no muscle involvement. A subset of patients with CADM has a specific antibody known as anti-melanoma differentiation-associated protein 5 (MDA5). The systemic associations of anti-MDA-5 CADM warrant an early recognition and management to prevent fetal sequelae. It is seen more commonly in white and Asian female individuals. The clinical features of anti-MDA5 antibody-positive CADM in other ethnic groups are not well reported. Here, we describe a case of CADM with identified autoantibodies against MDA5 in a Sudanese female patient presenting with characteristic cutaneous features in association with MDA5 autoantibodies: ulcerated Gottron's papules, painful palmar papules, shawl sign, and heliotrope sign. No evidence of pulmonary or systemic involvement was identified. Treatment with prednisolone and mycophenolate mofetil was initiated. This case emphasizes the importance of keeping a high level of suspicion and to recognize the unique clinical feature of this type of DM aiding in early treatment and preventing fatal outcomes.

Pharmacologic Treatment of Anti-MDA5 Rapidly Progressive Interstitial Lung Disease

Purpose of the Review

Idiopathic inflammatory myopathies are a heterogeneous group of autoimmune disorders. The presence of different autoantibodies allows clinicians to define distinct phenotypes. Antibodies against the melanoma differentiation-associated protein 5 gene, also called anti-MDA5 antibodies, are associated with a characteristic phenotype, the clinically amyopathic dermatomyositis with rapidly progressive interstitial lung disease. This review aims to analyze the different pharmacological options for the treatment of rapidly progressive interstitial lung disease in patients with anti-MDA5 antibodies.

Recent Findings

Evidence-based therapeutic recommendations suggest that the best initial approach to treat these patients is an early combination of immunosuppressive drugs including either glucocorticoids and calcineurin inhibitors or a triple therapy adding intravenous cyclophosphamide. Tofacitinib, a Janus kinase inhibitor, could be useful according to recent reports. High ferritin plasma levels, generalized worsening of pulmonary infiltrates, and ground-glass opacities should be considered predictive factors of a bad outcome. In this scenario, clinicians should consider rescue therapies such as therapeutic plasma exchange, polymyxin-B hemoperfusion, veno-venous extracorporeal membrane oxygenation, or even lung transplantation.

Summary

Combined immunosuppressive treatment should be considered the first-line therapy for patients with anti-MDA5 rapidly progressive interstitial lung disease. Aggressive rescue therapies may be useful in refractory patients.

Slowly progressive interstitial lung disease preceding typical dermatomyositis symptoms in anti-melanoma differentiation-associated gene 5 antibody-positive clinically amyopathic dermatomyositis

A 73-year-old woman who visited our hospital complaining of dry cough for three months was refractory to antimicrobial therapy. Chest computed tomography revealed subpleural consolidation. Specimens obtained from surgical lung biopsy revealed subpleural perilobular airspace organization and fibrosis. After the biopsy, mechanic's hand and Gottron's papules appeared, and anti-melanoma differentiation-associated gene 5 (MDA5) antibody was found to be positive. Subsequently, anti-MDA5 antibody measured in cryopreserved serum from her first admission proved to be positive. It is difficult to suspect the presence of anti-MDA-5 antibody in patients with interstitial lung disease without typical dermatomyositis symptoms or slow disease progression.

Recognition and Management of Cutaneous Connective Tissue Diseases

Connective tissue diseases (CTDs) encompass a broad spectrum of clinical presentations that involve multidisciplinary management. Cutaneous findings are common in CTD and careful examination of these features aids in appropriate diagnosis and subsequent evaluation. Thorough work-up of CTD is crucial to properly identify disease subtypes and systemic involvement. Management plans can be developed based on diagnosis and systemic manifestations of disease. Disease management often requires treatment with pharmacotherapies with potential for toxicities, further underscoring the importance of diagnostic accuracy in this patient population. Evolving research strives to better elucidate the pathogenic mechanisms of CTDs allowing for more targeted treatment modalities.

Initial predictors for short-term prognosis in anti-melanoma differentiation-associated protein-5 positive patients

Background

Anti-melanoma differentiation-associated protein-5 (anti-MDA5) positive patients are characterized by the high mortality rate caused by interstitial lung disease (ILD). We conducted a retrospective study to summarize the clinical features and identify the initial predictors for death in anti-MDA5 positive patients.

Methods

We designed a retrospective cohort of anti-MDA5 positive patients. The demographic and clinical data recorded on first admission, as well as the outcomes during the first six months follow-up, were collected. Predictors of rapidly progressive ILD (RPILD) and poor outcomes were calculated using logistic regression models and Cox proportional hazard regression models, respectively.

Results

A total of 90 anti-MDA5 positive patients were included in this study. Eighty-one (90%) patients presented ILD on admission and 35 (38.9%) patients developed RPILD subsequently. During the first six months of follow-up, 22 (24.4%) patients died of respiratory failure at an average time of 6.6 ± 5.9 weeks. Factors including disease duration < 2 months (OR 6.1, 95% CI 1.7–22.4, P = 0.007), serum ferritin ≥ 1500 ng/ml (OR 12.3, 95% CI 3.1–49.6, P < 0.001), CRP ≥ 13 mg/L (OR 4.6, 95% CI 1.3–16.9, P = 0.021) and total GGO score ≥ 4 (OR 6.3, 95% CI 1.8–21.9, P = 0.003), were identified as independent predictors for RPILD. Cox regression model showed that total CT GGO score ≥ 4 (HR 4.8, 95% CI 1.3–17.9, P = 0.020), KL-6 > 1600 U/ml (HR 3.7, 95% CI 1.5–9.1, P = 0.004) and CRP > 5.8 mg/L (HR 3.7, 95% CI 1.0–12.8, P = 0.044) were poor prognostic risk factors, however initial combined treatment (HR 0.3, 95% CI 0.1–0.8, P = 0.019) predicted good prognosis in anti-MDA5 positive patients.

Conclusion

Anti-MDA5 positive patients demonstrated a high prevalence of ILD on admission, leading to a high short-term mortality rate. Higher total GGO score, higher levels of initial KL-6 and CRP predict poor outcome in anti-MDA5 positive patients. However, initial intensive treatment may improve the prognosis.

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.

临床无肌病性皮肌炎与皮肌炎临床及免疫学特征比较

OBJECTIVE

To study the differences between clinically amyopathic dermatomyositis (CADM) and typical dermatomyositis (DM) on clinical and immunological features.

METHODS

By collecting clinical data of 106 CADM patients and 158 DM patients from January 2010 to June 2019 in the department of Rheumatology and Immunology, Peking University People's Hospital, the clinical characteristics and immunological features in the two groups were compared, and the distribution characters and the clinical meanings of myositis autoantibodies were discussed in the two groups respectively. Myositis autoantibodies were measured by immunoblotting according to the manufacturers' instructions.

RESULTS

In the aspects of clinical manifestations, CADM presented more with onset of interstial lung diseases (ILD) compared with DM (20.7% vs. 7.6%, P=0.002), and CADM-ILD was more likely to be acute ILD (58.3% vs. 26%, P < 0.001), and there were no differences between CADM and DM in cutaneous manifestations, accompanied with connective tissue disease (CTD) and malignancy. In CADM, the positive rate of rheumatoid factors and antinuclear antibodies was lower in DM. The most common myositis specific autoantibodies (MSAs) in CADM were anti-MDA5 (36%), anti-PL-7 (11.2%) and anti-TIF-1γ (10.1%). The most common MSAs in DM were anti-Jo-1 (19.2%), anti-TIF-1γ (11.5%) and anti-MDA5 (11.5%). Anti-MDA5 was correlated with acute ILD and skin ulceration both in CADM and DM; in CADM, skin ulceration was not associated with the titer of anti-MDA5; while in DM, skin ulceration was associated with high titer of anti-MDA5. In DM, anti-TIF-1γ was correlated with heliotrope eruption, V/shawl neck sign, perionychia erythma and malignancy, and higher rate of malignancy was seen in all titers of the anti-TIF-1γ positive patients. In CADM, anti-TIF1-γ showed no correlation with clinical manifestations. The most common myositis associated autoantibody was anti-Ro-52 both in CADM and DM. In CADM, anti-Ro-52 was associated with Raynaud's phenomenon and chronic ILD, while in DM, anti-Ro-52 was associated with mechanic's hands, noninfectious fever and accompanied CTD.

CONCLUSION

Compared with DM, ILD is more likely to be acute in CADM. It is different between CADM and DM about the distribution of myositis autoantibodies and the clinical significance of the same myositis antibody, and the clinical significance of some myositis antibodies is related to titers.

Nintedanib and intensive immunosuppressive therapy to treat rapidly progressive interstitial lung disease presenting anti-ARS antibodies

We describe a case of fulminant onset, rapidly progressive-interstitial lung disease (RP-ILD) with anti-ARS antibodies (anti-PL-7). The patient was successfully treated with nintedanib in addition to intensive immunosuppressive therapies, including intravenous cyclophosphamide. Nintedanib has just been approved for treatment of progressive fibrosing ILD, but to date, no reports of RP-ILD treated with nintedanib have been published. This case report may advance discussions regarding the use and timing of nintedanib in treating RP-ILD.

A Japanese-American female with rapidly progressive interstitial lung disease associated with clinically amyopathic dermatomyositis

Patients with clinically amyopathic dermatomyositis (CADM) have a risk of developing rapidly progressive interstitial lung disease (ILD). CADM-ILD is associated with the anti-MDA-5 antibody. In the USA, however, patients with CADM have these antibodies less frequently than those in Japan. In addition, those with this disorder are less often complicated with rapidly progressive ILD than those in Japan. We present a case of a 42-year-old Japanese-American female with a 3-month history of a rash on her hands and face with joint pain. Based on the negative results from lupus tests, her primary care provider and a rheumatologist treated her with steroids, hydroxychloroquine, and methotrexate. During treatment, the patient started noticing shortness of breath because of pneumonia, which was revealed by a CT scan. The woman was finally diagnosed with acute respiratory failure due to CADM with ILD. She underwent a double lung transplant as well as treatment with multiple immunosuppressive agents and repeated plasma exchange but died 15 days after transplantation. Her clinical course is similar to that of Japanese patients with CADM-ILD. Outside Japan, primary care providers, rheumatologists, and dermatologists, as well as pulmonary physicians, may be less familiar with this disorder than those in Japan. Since CADM-ILD progresses very quickly and could be fatal, these doctors should be aware of this disease to treat such patients as soon as possible, particularly when seeing a patient of Japanese descent.

Acute lung injury after plasma exchange in a patient with anti-MDA5 antibody-positive, rapidly progressive, interstitial lung disease：A case report

The presence of anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 Ab) is closely associated with rapidly progressive interstitial lung disease (RP-ILD) in patients with clinically amyopathic dermatomyositis. Despite intensive immunosuppressive therapies, some of these patients still have a poor prognosis with few treatment options. Although removal of pathogenic autoantibodies and cytokines by plasma exchange (PE) could be a treatment option, its safety and efficacy have never been determined. We report a patient with anti-MDA5 Ab-positive RP-ILD who was refractory to intensive therapies including steroids, cyclosporine, and intravenous cyclophosphamide, and then treated by PE to prevent the progression of RP-ILD. Shortly after the initiation of PE therapy, however, his respiratory condition suddenly deteriorated due to acute pulmonary edema and the patient died on the following day. Transfusion-related acute lung injury (TRALI) would be the most likely cause of the acute pulmonary edema because there was no sign of circulatory overload. To the best of our knowledge, this is the first report showing a critical adverse event associated with PE therapy for these patients. This case supports the idea that the presence of ILD could increase a risk for TRALI and therefore we should carefully evaluate the eligibility for PE therapy of anti-MDA5 Ab-positive RP-ILD patients given the risk of acute lung injury. Further studies collecting more clinical data are necessary to assess the efficacy, safety, and risk factors of PE therapy for these patients.

Noninvasive positive pressure ventilator deteriorates the outcome of pneumomediastinum in anti-MDA5 antibody-positive clinically amyopathic dermatomyositis

BACKGROUND

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab)-positive clinically amyopathic dermatomyositis (CADM) with pneumomediastinum (PNM) is a life-threatening condition. We aim to determine the prognostic factors affecting survival of patients with anti-MDA5 Ab-positive CADM complicated with PNM.

METHODS

We retrospectively established a cohort of patients with anti-MDA5 Ab-positive CADM complicated with PNM from April 2013 to July 2019. Demographic data and clinical characteristics from medical records were analyzed and variables were compared between survivors and nonsurvivors. We performed univariate and multivariate survival analyses by Cox regression. Survival curves were depicted by the Kaplan-Meier method.

RESULTS

Among 133 patients with anti-MDA5 Ab-positive CADM, 20 were diagnosed with PNM. The cumulative estimated Kaplan-Meier survival rate was 85% at 1 week, 55% at 1 month, and 40% at 1 year. Univariate analysis indicated several factors associated with survival. Worse liver function (AST, p = 0.043; LDH, p = 0.002; TBIL, p = 0.038), higher CRP level (p = 0.044), higher HRCT score (p = 0.022), and using noninvasive positive pressure ventilation (NPPV) (p < 0.01) were associated with poor prognosis. In a multivariate Cox regression model, AST level and using NPPV were indicated to be independent predictors of poor prognosis.

CONCLUSION

In this research, we found that the incidence rate of PNM in anti-MDA5 Ab-positive CADM was 15.5%, obviously higher than in classical DM. The application of noninvasive positive pressure ventilator (NPPV) and higher AST level were independent risk factors for survival.Key Points• Anti-MDA5 Ab-positive CADM complicated with PNM is a life-threatening condition with an incidence rate of 15.5%.• The application of NPPV and worse liver function were independent risk factors for survival of anti-MDA5 Ab-positive CADM patients complicated with PNM.

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.

Utilize lung ultrasound B-lines and KL-6 to monitor anti-MDA-5 antibody-positive clinically amyopathic dermatomyositis-associated interstitial lung disease: a case report and literature review

In the past decade, lung ultrasound (LUS) B-lines and serum Krebs von den Lungen-6 (KL-6) antigen have been recognized as biomarkers of the connective tissue disease-associated interstitial lung diseases (CTD-ILDs). Robust data have demonstrated that B-lines total numbers and KL-6 levels are correlated with high-resolution computed tomography findings, pulmonary function test, and some clinical parameters in CTD-ILDs. However, limited data are available regarding the use of these two biomarkers to follow CTD-ILDs. Herein, we report a case with anti-melanoma differentiation-associated gene 5 antibody-positive clinically amyopathic dermatomyositis-associated ILD, successfully treated with high-dose methylprednisolone, cyclophosphamide, intravenous immunoglobulin, pirfenidone, and followed using lung ultrasound and KL-6.

Histological Findings of Organizing Pneumonia, Based on Transbronchial Lung Biopsy, May Predict Poor Outcome in Polymyositis and Dermatomyositis: Report of Two Autopsied Cases

Interstitial lung disease in polymyositis and dermatomyositis is a serious complication, associated with poor prognosis. In this article, we describe two cases with histological findings of organizing pneumonia, based on transbronchial lung biopsy. One is a 66-year-old female patient with clinically amyopathic dermatomyositis with anti-melanoma differentiation-associated gene 5 antibody, and another is a 61-year-old female patient with polymyositis with anti-Jo-1 antibody. Both of our cases rapidly deteriorated to death, and autopsy findings showed diffuse alveolar damage. Our experience indicates that transbronchial biopsy findings of organizing pneumonia may be a poor prognostic factor in clinically amyopathic dermatomyositis and polymyositis, in spite of the profile of myositis-specific antibodies.

Differential clinical features of patients with clinically amyopathic dermatomyositis who have circulating anti-MDA5 autoantibodies with or without myositis-associated autoantibodies

BACKGROUND

Anti-melanoma differentiation-associated gene 5 (MDA5) autoantibodies have been identified as myositis-specific autoantibodies that are often associated with clinically amyopathic dermatomyositis (CADM) and a poor prognosis due to rapidly progressive interstitial lung disease (RP-ILD) in East Asian patients. Besides anti-MDA5 autoantibodies, patients with CADM may have myositis-associated autoantibodies (MAAs), which characterize other connective tissue diseases such as rheumatoid arthritis and Sjögren's syndrome. However, the clinical significance of the coexistence of anti-MDA5 autoantibodies and MAAs in patients with CADM remains unclear.

METHODS

We retrospectively analyzed 24 patients with CADM who had anti-MDA5 autoantibodies. Their clinical phenotypes including laboratory test results, high-resolution lung computed tomography data, response to therapy, and prognosis were compared between those who were positive and negative for MAAs, such as antinuclear antibody (ANA), anti-cyclic citrullinated peptide (CCP), anti-SSA, and anti-SSB antibodies.

RESULTS

Among 24 patients, 9 (37.5%) additionally had at least one of the MAAs examined in this study: 1 patient was positive for ANA, 5 for anti-CCP, 5 for either anti-SSA or anti-SSB, 1 for anti-cardiolipin, and 1 for anti-Scl-70. Although all anti-MDA5-positive patients with CADM had ILD, the MAA-positive patients showed a lower risk of developing RP-ILD (p = 0.03), a more favorable response to combination therapy of corticosteroids and immunosuppressive agents, and a lower mortality rate than patients with no MAAs (p = 0.03).

CONCLUSIONS

Our data suggest that anti-MDA5-positive patients with CADM who also have MAAs have a better prognosis than those without MAAs; thus, anti-MDA5 autoantibodies by themselves may not be strong predictors of worse clinical outcomes in patients with CADM. Coexistent MAAs could be biomarkers for a favorable prognosis in anti-MDA5-positive patients with CADM.

The prevalence and clinical significance of anti-PUF60 antibodies in patients with idiopathic inflammatory myopathy

Autoantibodies against poly-U-binding factor 60 kDa protein (PUF60) have been reported in Caucasian dermatomyositis (DM) patients. However, their clinical significance in idiopathic inflammatory myopathy (IIM) remains to be fully clarified. Our objective was to analyze the prevalence and clinical significance of anti-PUF60 antibodies in a large cohort of Chinese IIM patients. In our study, 388 IIM patients, 301 disease controls, and 167 healthy controls (HCs) were involved. An enzyme-linked immunosorbent assay (ELISA) was developed to detect serum anti-PUF60 levels and was validated using immunoblotting methods. Unpaired Mann-Whitney U test and Spearman correlation analysis were used when appropriate. Anti-PUF60 antibodies were observed in IIM patients at a frequency of 10.6% (41/388). Subgrouping analysis revealed that the prevalence of anti-PUF60 antibodies was 10% in DM, 5.5% in polymyositis (PM), 10% in immune-mediated necrotizing myositis (IMNM), and 26.5% in myositis-overlap syndrome. Anti-PUF60 antibodies were also observed in systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and Sjögren's syndrome (SS) patients at a positive rate of 17.3, 14.5, and 10.1% respectively. Intriguingly, anti-PUF60 antibodies were frequently observed in clinically amyopathic dermatomyositis (CADM) patients and DM patients without currently known myositis autoantibodies. Furthermore, DM patients with anti-PUF60 antibodies had higher prevalence of skin ulcerations. Moreover, longitudinal investigation in eight DM patients with anti-PUF60 antibodies revealed that the antibodies levels decreased with disease remission. Anti-PUF60 antibodies were nonspecific for myositis, since they could be detected in other rheumatic diseases. Further investigation of anti-PUF60 antibodies may reveal shared pathogenic pathways in systemic autoimmune disorders.

Rapidly progressive interstitial lung disease due to anti-MDA5 antibodies without skin involvement: a case report and literature review

Anti-MDA5 antibodies have been strongly associated with rapidly progressive interstitial lung disease (RP-ILD) in dermatomyositis (DM) patients, especially in the clinically amyopathic subset (CADM). We present a case of anti-MDA5 antibody-associated RP-ILD in a patient with arthritis but with no other clinical signs suggestive of DM or CADM successfully treated with a combination of cyclophosphamide, cyclosporine and corticoids. A review of the literature was also done. Despite its rarity, anti-MDA5 antibody-associated ILD should be suspected in cases of RP-ILD even without other signs of DM or CADM as prompt and aggressive treatment could improve prognosis.

Correlation between disease activity and serum ferritin in clinically amyopathic dermatomyositis with rapidly-progressive interstitial lung disease: a case report

Background

Clinically amyopathic dermatomyositis with anti-Melanoma Differentiation-Associated gene 5 (MDA5) antibody often presents with severe interstitial lung disease. Although serum ferritin level is known to reflect interstitial lung disease activity, there are few case reports describing this association.

Case presentation

A 58-year-old man was referred to our outpatient clinic with a 3-week history of cough and respiratory distress. He had erythema over the V area of the neck and a Gottron’s sign. Chest computed tomography revealed diffuse ground-glass opacities and reticular shadows in both lungs. Test for anti-MDA5 antibody was positive. After admission, he received triple combination therapy (methylprednisolone pulse therapy, tacrolimus, and cyclophosphamide). However, his respiratory condition worsened as the serum ferritin level increased. Despite no apparent deterioration on chest radiography, he ultimately died due to respiratory failure.

Conclusions

In this case, triple combination therapy was not effective for the patient’s respiratory condition. The serum ferritin level was correlated with disease activity and was more useful than chest radiography for monitoring clinical status.

Clinical effects of direct hemoperfusion using a polymyxin B-immobilized fiber column in clinically amyopathic dermatomyositis-associated rapidly progressive interstitial pneumonias

Background

Rapidly progressive interstitial pneumonias (RPIPs) associated with clinically amyopathic dermatomyositis (CADM) are highly resistant to therapy and have a poor prognosis. Multimodal therapies, including direct hemoperfusion using a polymyxin B-immobilized fiber column (PMX-DHP), have a protective effect on RPIPs. We evaluated the effects of PMX-DHP on CADM-associated RPIPs.

Methods

We retrospectively enrolled 14 patients with CADM-associated RPIPs and acute respiratory failure treated with PMX-DHP, corticosteroids, and immunosuppressive agents. Clinical manifestations were compared between survivors and non-survivors at 90 days after PMX-DHP.

Results

The survival rate at 90 days after PMX-DHP was 35.7% (5/14). Before PMX-DHP, the survivor group exhibited a significantly higher PaO₂/FiO₂ (P/F) ratio and serum surfactant protein-D (SP-D) levels and significantly lower lactate dehydrogenase (LDH) and ferritin levels than the non-survivor group. Platelet counts were significantly decreased after PMX-DHP therapy in both groups, but remained higher in the survivor group than the non-survivor group over the course of treatment. Anti-melanoma differentiation-associated gene 5 (MDA-5) antibody positive patients demonstrated a poor 90-day survival rate, lower platelet counts and P/F ratio, and higher LDH levels than anti-MDA-5 antibody negative patients.

Conclusions

CADM-associated RPIPs with anti-MDA-5 antibody is associated with a very poor prognosis. A higher P/F ratio and SP-D level, lower LDH and ferritin levels, higher platelet counts, and anti-MDA-5 antibody negativity are important prognostic markers in patients with CADM-associated RPIPs treated with PMX-DHP.

Rapidly progressive interstitial lung disease due to anti-MDA-5 antibody-positive clinically amyopathic dermatomyositis complicated with cervical cancer: Successful treatment with direct hemoperfusion using polymyxin B-immobilized fiber column therapy

The anti-melanoma differentiation-associated gene 5 (MDA-5) antibody is a marker of clinically amyopathic dermatomyositis (CADM) and rapidly progressive interstitial lung disease (ILD) with acute respiratory failure. A 35-year-old woman with cervical cancer showed Gottron's papules, severe hypoxemia, and diffuse ground-glass opacities on chest computed tomography. She was diagnosed with rapidly progressive ILD associated with CADM. Her serum was positive for the anti-MDA-5 antibody. Combination therapy with corticosteroids, immunosuppressants, and direct hemoperfusion using polymyxin B-immobilized fiber column (PMX-DHP) improved her respiratory dysfunction. Eventually, surgery for the cancer was performed successfully. This is the first case to demonstrate the efficacy of PMX-DHP for rapidly progressive ILD with anti-MDA-5 antibody-positive CADM and a malignancy.

Assessment of Mortality in Autoimmune Myositis With and Without Associated Interstitial Lung Disease

PURPOSE

Among patients with autoimmune myositis, associated interstitial lung disease (MA-ILD) is a known contributor of excess morbidity and mortality. Recent data on survival in idiopathic inflammatory myopathies originate primarily in Asia and Europe and vary widely. We sought to examine mortality in a large U.S. myositis cohort focusing in particular on the impact of associated ILD.

METHODS

A cross-sectional analysis of participants from the Johns Hopkins Myositis Center with autoimmune myositis (polymyositis [PM], dermatomyositis [DM], or clinically amyopathic dermatomyositis [CADM]) was conducted. The primary outcome assessed was all-cause mortality. Cumulative mortality rates were estimated using the Kaplan-Meier test; the Cox proportional hazards model was used to compare group differences in survival.

RESULTS

Eight hundred and thirty-one participants were included with a median follow-up time of 4.5 years. Four hundred thirty-eight (53 %) had PM, 362 (43 %) had DM, and 31 (4 %) had CADM. Ninety-four (11 %) participants had clinically evident ILD. Overall, 51 participants died (6 %). In those without ILD, the survival rates at 1, 5, and 10 years were 99, 95, and 90 %, respectively. In those with ILD, the survival rates at 1, 5, and 10 years were 97, 91, and 81 %, respectively. The risk of death was statistically significantly higher among participants with ILD compared to those without ILD (HR 2.13. 95 % CI 1.06-4.25; p = 0.03).

CONCLUSIONS

We analyzed one of the largest known cohorts of patients with autoimmune myositis and found significantly higher mortality rates among those with clinically evident ILD compared to those without clinically evident ILD. Our results suggest that ILD remains an important and significant source of mortality in patients with inflammatory myopathies and as such should be screened for and treated aggressively.

MDA5-positive dermatomyositis: an uncommon entity in Europe with variable clinical presentations

Clinically amyopathic dermatomyositis (CADM), described almost 50 years ago, is defined on the basis of still not validated criteria and characterized by skin findings almost without muscle weakness. Autoantibodies directed against the cytosolic pathogen sensor MDA5 (CADM 140) can mark this subtype of dermatomyositis which has been reported to associate, in particular ethnic groups, with severe progressive interstitial lung disease, poor prognosis and an hyperferritinemic status resembling hemophagocytic-like syndromes. MDA5 may be relevant in that Interferon-signature claimed to characterize inflammatory myopathies and dermatomyosits itself, but its role is not clear. However, the titre of anti-MDA5 autoantibodies seems to correlate with the outcome. In Caucasian populations the association between anti-MDA5 positive CADM and rapidly progressive interstitial lung disease seems to be weaker, but the limited numbers of patients described so far could explain the lack of statistical significance. As a fact, European patients with circulating anti-MDA5 autoantibodies may be clinically inhomogeneous and exhibit different rates of severity. The two patients affected by anti-MDA5 positive dermatomyositis described hereafter provide a clear example of the extreme variability of the disease in terms of laboratory findings and clinical features.

Incidence and impact of interstitial lung disease and malignancy in patients with polymyositis, dermatomyositis, and clinically amyopathic dermatomyositis: a retrospective cohort study

The aims of this study were to retrospectively review Japanese consecutive cases of polymyositis (PM), dermatomyositis (DM), and clinically amyopathic dermatomyositis (CADM), focusing on interstital lung disease (ILD) and malignancy, and to document any differences in the incidence, clinical features, and impact on prognosis among patients with PM, DM, and CADM.

We retrospectively reviewed 62 consecutive patients diagnosed with PM, DM, and CADM according to Bohan and Peter’s criteria (PM/DM) and Sontheimer’s criteria and Gerami’s criteria (CADM), focusing on ILD and malignancy.

ILD occurrence rates were 48 % (11/23) in patients with PM, 46 % (11/24) in DM, and 100 % (15/15) in CADM. Malignancy occurred during diagnosis or the observation period in 14 patients; 86 % were without ILD, and 64 % were DM without ILD. Multivariate logistic regression analysis showed that the risk of newly diagnosed malignancy was significantly lower in patients with ILD [odds ratio, 0.0688; 95 % confidence interval (CI), 0.00127–0.372; p = 0.00190] and significantly higher in patients with DM (odds ratio, 5.21; 95 % CI, 1.17–23.1; p = 0.0299) than in other patients. Patients with malignancies had shorter survival than those without malignancies; no clinically meaningful difference in survival was observed among the different myositis types and for presence of ILD. In CADM-ILD, 80 % fatal cases died from refractory ILD ≤90 days from the first visit; neither death nor recurrence occurred subsequently.

In conclusion, a positive association between DM and malignancy and a negative association between ILD and malignancy were noted. In the present study, malignancy was a predictor of poor long-term prognosis, but ILD were not. ILD associated with CADM contributed greatly to poor short-term prognosis, but neither death nor recurrence occurred subsequently.