Anti-MDA5 positive clinically amyopathic dermatomyositis presenting with severe cardiomyopathy

Increased histological severity and chronicity of interface inflammation in anti-MDA5 dermatomyositis-A comparative dermatopathological analysis

Anti-melanoma differentiation-associated gene 5 (MDA5) dermatomyositis is characterized by serological detection of anti-MDA5 antibody and rapidly progressive interstitial lung disease. In this study, the largest cohort of skin biopsies to date of anti-MDA5 dermatomyositis was reviewed and compared with cases of dermatomyositis with negative serology. Findings contribute to the histological diagnosis and evaluation of the severity of cutaneous inflammation in anti-MDA5 dermatomyositis. Skin biopsies collected over a 7-year period from individuals with clinically and histologically confirmed dermatomyositis with anti-MDA5 serology were reviewed. A total of 46 cases with 17 anti-MDA5 positive cases were retrieved. Patients with positive antibody were younger (53.7 vs. 60.6 years, p = .013). No differences in epidermal changes (p > .05) were observed. Pertaining to interface changes, anti-MDA5 dermatomyositis showed a higher degree of pigmentary incontinence (p = .014), suggesting increased and sustained cutaneous inflammation. Periodic acid-Schiff (PAS) stain demonstrated a greater degree of basement membrane thickening (p = .045). Other parameters, including dermal inflammation, dermal mucin deposition and vasculitic/vasculopathic features did not show statistical difference between anti-MDA5 positive and negative dermatomyositis (p > .05). Findings suggest increased cutaneous inflammation for anti-MDA5 dermatomyositis. In skin biopsies, marked pigmentary incontinence or basement membrane thickening should raise suspicion of anti-MDA5 dermatomyositis.

Subcutaneous tissue involvement in idiopathic inflammatory myopathies: Systematic literature review including three new cases and hypothetical mechanisms

INTRODUCTION

Involvement of subcutaneous tissue in idiopathic inflammatory myopathies (IIM) is poorly known.

METHODS

We conducted a systematic review of the literature regarding panniculitis and lipodystrophy/lipoatrophy in juvenile and adult IIM via PubMed/Medline, Embase and Scopus databases. Three local observations are included in this review. Epidemiological, clinical, paraclinical and therapeutic data were collected.

RESULTS

Panniculitis appears to be more common in adults than in juveniles. It was mainly localised in the upper and lower limbs. Panniculitis improved in most cases with steroids and panniculitis and myositis had a similar course in 83.3% and 72.2% of cases in juveniles and adults, respectively. Lipodystrophy appeared to be more frequent in juveniles and was only observed in dermatomyositis in both juveniles and adults. Lipodystrophy was mainly partial in juveniles and adults. The median time from myositis to the diagnosis of lipodystrophy was 6 years [0-35] and 2.5 years [0-10] in juveniles and adults, respectively. Lipodystrophy was associated with anti-TIF1 gamma auto-antibody positivity, a polycyclic/chronic course of myositis and the occurrence of calcinosis and might be an indicator of poor disease control.

CONCLUSION

Adipose tissue involvement, particularly lipodystrophy, occurs almost exclusively in dermatomyositis. The insidious onset and lack of awareness of the diagnosis may underestimate its prevalence. Larger studies are needed to identify possible risk factors in these patients, to better potential underlying pathophysiological process, in order to discuss potential therapeutic targets.

Cardiac involvement in anti-MDA5 dermatomyositis: a case-based review

Among myositis-specific antibodies, anti-melanoma differentiation-associated gene 5 (anti-MDA5) is one of the antibodies with a unique spectrum that is expressed principally in clinically amyopathic dermatomyositis (CADM) and, to a lesser extent, in dermatomyositis (DM). In addition to muscle and classical skin involvement, patients with anti-MDA5 DM/CADM are characterized by the expression of rapidly progressive interstitial lung diseases, vasculopathic lesions, and non-erosive arthritis. Although cardiac involvement has been described in other inflammatory myopathies, such as myocarditis, pericarditis, and conduction disorders, in anti-MDA5 DM/CADM patients, heart disease is infrequent. We report a case of a young male presenting with constitutional symptoms, polyarthritis, skin ulcers, and mild muscle weakness who developed an episode of high ventricular rate atrial fibrillation during his hospitalization. The anti-MDA5 DM diagnosis was supported by increased muscular enzymes, positive anti-MDA5 and anti-Ro52 antibodies, and the presence of organizing pneumonia. He was treated with high-dose glucocorticoids, rituximab, and beta-blocker drugs and received pharmacological cardioversion, which improved his myopathy symptoms and stabilized his heart rhythm. Here, we describe eight similar cases of anti-MDA5 DM/CADM with cardiac involvement. The case presented and the literature reviewed reveal that although rare, physicians must be aware of cardiac disease in patients with suggestive symptoms to guarantee early assessment and treatment, thereby reducing life-treating consequences.

Myocardial involvement is not rare in anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis/clinically amyopathic dermatomyositis: a retrospective study

Objectives

Studies concerning myocardial involvement (MI) in patients with anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis/clinically amyopathic dermatomyositis (anti-MDA5 Ab+ DM/CADM) are scarce. We aimed to characterize MI in our anti-MDA5 Ab+ DM/CADM cohort and to investigate its association with prognosis.

Methods

In this single-center retrospective study, anti-MDA5 Ab+ hospitalized DM/CADM patients who underwent transthoracic echocardiography (TTE) were enrolled. Myocardial involvement was diagnosed according to abnormal cardiac structure and function detected by TEE. Clinical features and cardiac examination findings of patients with MI were analyzed. Clinical features, laboratory findings, complications, and treatments were compared between MI and non-MI, deceased, and survival patients. Logistic regression analysis was used to explore the independent risk factors for the occurrence of MI and prognostic factors for these patients.

Results

Seventy-six hospitalized patients with anti-MDA5 Ab+ DM/CADM were enrolled. Twelve (15.8%) patients were diagnosed with MI. Of the 12 patients, three underwent cardiac magnetic resonance imaging (CMR) and late gadolinium enhancement (LGE) were noted for them. TEE revealed that eight (66.7%) patients had left atrial and/or ventricular enlargement, three (25.0%) had cardiac hypertrophy, six (50.0%) had diffuse ventricular wall dyskinesia, and seven (58.3%) had diastolic dysfunction. Six (50.0%) patients with MI developed heart failure (HF) during treatment. Of the 12 patients, one patient died of HF caused by myocarditis, three died of infection, and four died of exacerbation of rapidly progressive interstitial lung disease (RP-ILD). Logistic regression analysis revealed that dysphagia (OR 3.923, 95% CI 1.085, 14.181), NT-proBNP >600 pg/ml (OR 18.333, 95% CI 1.508, 222.875), and increased peripheral white blood cells (OR 1.201, 95% CI 1.003, 1.438) were risk factors for the occurrence of MI, but plasma albumin (OR 0.892, 95% CI 0.796, 0.999) was a protective factor. Both MI (OR 5.984, 95% CI 1.174, 30.496) and RP-ILD (OR 11.875, 95% CI 2.796, 50.411) were independent risk factors for the mortality of these anti-MDA5 Ab+ DM/CADM patients.

Conclusion

Myocardial involvement is not rare and is an independent poor prognostic factor of anti-MDA5 Ab+ DM/CADM patients. Cardiac abnormality screening is necessary for them.

Cardiovascular Abnormalities in Juvenile Dermatomyositis: A Scoping Review for the Clinical Rheumatologists

Juvenile dermatomyositis (JDM) is a common form of inflammatory myositis in children. Vasculopathy and endothelial dysfunction play significant roles in the pathogenesis of JDM. Cardiac involvement in JDM is often underestimated, and it may be a potential indicator of poor prognosis. Cardiac dysfunction in JDM can occur both in the acute and chronic stages of the disease. Amongst the acute complications, acute congestive heart failure (CHF), myocarditis, arrhythmia, and complete heart block are common. However, these remain unrecognized due to a lack of overt clinical manifestations. Increased rates of cardiovascular abnormalities have been noted with anti-SRP and anti-Jo 1 auto-antibody positivity. Long-term follow-up studies in JDM have shown an increased prevalence of hypertension, atherosclerosis, coronary artery disease, and metabolic syndrome in adolescence and adulthood. Monitoring of body-mass index, blood pressure, and laboratory evaluation of fasting glucose and lipid profile may help in identifying metabolic syndrome in children with JDM. Steroid-sparing agents, daily exercise, and a healthy diet may reduce such long-term cardiac morbidities. Current use of multimodality imaging such as stress-echocardiography, contrast-enhanced echocardiography, cardiac magnetic resonance imaging, and positron emission tomography has increased the diagnostic yield of subclinical heart disease during acute and chronic stages of JDM. This review elaborates on different aspects of cardiac dysfunction in JDM. It also emphasizes the importance of cardiac screening in long-term follow-up of children with JDM.

ECG Changes Through Immunosuppressive Therapy Indicate Cardiac Abnormality in Anti-MDA5 Antibody-Positive Clinically Amyopathic Dermatomyositis

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody, a dermatomyositis (DM)-specific antibody, is strongly associated with interstitial lung disease (ILD). Patients with idiopathic inflammatory myopathy (IIM) who are anti-MDA5 antibody positive [anti-MDA5 (+)] often experience chest symptoms during the active disease phase. These symptoms are primarily explained by respiratory failure; nevertheless, cardiac involvement can also be symptomatic. Thus, the aim of this study was to investigate cardiac involvement in anti-MDA5 (+) DM. A total of 63 patients with IIM who underwent electrocardiography (ECG) and ultrasound cardiography (UCG) during the active disease phase from 2016 to 2021 [anti-MDA5 (+) group, n = 21; anti-MDA5-negative (-) group, n = 42] were enrolled in the study, and their clinical charts were retrospectively reviewed. The ECG and UCG findings were compared between the anti-MDA5 (+) and anti-MDA5 (-) groups. All anti-MDA5 (+) patients had DM with ILD. The anti-MDA5 (+) group showed more frequent skin ulcerations and lower levels of leukocytes, muscle enzymes, and electrolytes (Na, K, Cl, and Ca) than the anti-MDA5 (-) group. According to the ECG findings obtained during the active disease phase, the T wave amplitudes were significantly lower for the anti-MDA5 (+) group than for the anti-MDA5 (-) group (I, II, and V4-6 lead; p < 0.01; aVF and V3, p < 0.05). However, the lower amplitudes were restored during the remission phase. Except for the E wave, A wave and Sep e', the UCG results showed no significant differences between the groups. Four patients with anti-MDA5 (+) DM had many leads with lower T wave and cardiac abnormalities (heart failure, diastolic dysfunction, myocarditis) on and after admission. Though anti-MDA5 (+) patients clinically improved after immunosuppressive therapy, some of their ECG findings did not fully recover in remission phase. In conclusion, anti-MDA5 (+) DM appears to show cardiac involvement (electrical activity and function) during the active phase. Further studies are necessary to clarify the actual cardiac condition and mechanism of these findings in patients with anti-MDA5 (+) DM.

Dermatomyositis With Anti-MDA5 Antibodies: Bioclinical Features, Pathogenesis and Emerging Therapies

Anti-MDA5 dermatomyositis is a rare systemic autoimmune disease, historically described in Japanese patients with clinically amyopathic dermatomyositis and life-threatening rapidly progressive interstitial lung disease. Subsequently, the complete clinical spectrum of the disease was enriched by skin, articular and vascular manifestations. Depending on the predominance of these symptoms, three distinct clinical phenotypes with different prognosis are now defined. To date, the only known molecular component shared by the three entities are specific antibodies targeting MDA5, a cytosolic protein essential for antiviral host immune responses. Several biological tools have emerged to detect these antibodies, with drawbacks and limitations for each of them. However, the identification of this highly specific serological marker of the disease raises the question of its role in the pathogenesis. Although current knowledge on the pathogenic mechanisms that take place in the disease are still in their enfancy, several lines of evidence support a central role of interferon-mediated vasculopathy in the development of skin and lung lesions, as well as a possible pathogenic involvement of anti-MDA5 antibodies. Here, we review the clinical and biological evidences in favor of these hypothesis, and we discuss the contribution of emerging therapies that shed some light on the pathogenesis of the disease.

Painless Panniculitis upon the Treatment of Clinically Amyopathic Dermatomyositis with Anti-MDA5 Antibody

Panniculitis, a rare cutaneous manifestation in patients with dermatomyositis (DM), usually presents as a painful erythematous lesion. We herein report a 32-year-old woman with panniculitis that appeared as an indurated plaque without pain or redness after a 4-month episode of clinically amyopathic DM during treatment with prednisolone and tacrolimus. She experienced no pain; however, the firmness and extent gradually worsened. Based on our findings, including the histopathological results, DM panniculitis was diagnosed. Azathioprine was additionally administered, leading to remission. DM panniculitis can develop as a painless induration during immunosuppressive treatment, and azathioprine may be a useful treatment.

Immunotherapy reversed myopathy but not cardiomyopathy in a necrotizing autoimmune myopathy patient with positive anti-SRP and MDA-5 autoantibodies

Background

Necrotizing autoimmune myopathy (NAM) is pathologically characterized by myofiber necrosis and regeneration with paucity or absence of inflammatory cells in muscle biopsy. Two autoantibodies, namely anti-signal recognition particle (SRP)-antibodies and anti-3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR)-antibodies, are typically specific with NAM. Anti-SRP-positive NAM can be associated with cardiomyopathy which responds well to immunotherapy. Here we reported an anti-SRP-antibody and anti-MDA5-antibody NAM patient who developed severe cardiomyopathy after gaining significant improvement of myopathy and subsequently accepted heart transplantation.

Case presentation

A NAM case with both positive anti-SRP and MDA-5 antibodies who gained significant improvement of the skeletal muscle weakness with immunotherapy, but 3 years later he developed severe dilated cardiomyopathy and at last received heart transplantation. Myocardial biopsy showed disarranged and atrophic myofibers, remarkable interstitial fibrosis without inflammatory infiltrates. Immunohistochemistry analysis revealed increased polyubiquitin-binding protein p62/SQSTM1 protein expression and the positive staining of cleaved-caspase 3 in a few cardiomyocytes. After the transplantation, the patient was symptom-free on oral prednisone (10 mg/day) and tacrolimus (2 mg/day).

Conclusions

We described the first case of anti-SRP and anti-MAD5 positive NAM who had received heart transplantation because of cardiopathy. Though the myopathy had been clinically improved after immunotherapy, the cardiomyopathy remained progressive and lethal. The processes of dysfunctional autophagy and augmented apoptosis were putatively pathophysiological mechanisms underlying cardiac damage in anti-SRP and anti-MAD5 positive NAM.

A rare form of dermatomyositis associated with muscle weakness and normal creatine kinase level

We present a case study of a 61-year-old Vietnamese woman who presents with features of dermatomyositis (DM), including Gottron’s papules, heliotrope rash, cutaneous ulcers, generalised weakness and pain, and weight loss with normal levels of creatine kinase (CK). She demonstrated features of interstitial lung disease and subsequently tested positive for anti-melanoma differentiation-associated gene 5 and anti-small ubiquitin-like modifier 1 activating enzyme antibodies, which belong to a DM subtype known as clinically amyopathic dermatomyositis and do not present with raised CK. She received standard treatment for DM, including oral prednisolone, hydroxychloroquine, mycopheonlate and topical betamethasone. The treatment successfully reversed skin changes; however, the patient remained generally weak and unable to carry out her activities of daily living.

Myositis Specific Autoantibodies: A Clinical Perspective

Dermatomyositis (DM) is an idiopathic inflammatory condition characterized by myositis and variable skin manifestation. The existence of myositis specific autoantibodies usually manifests with varying degrees of skin or muscle inflammations. The condition has a well-established association with most clinical phenotypes, and these autoantibodies are useful in informing the diagnosis, management and prognosis of the disease. DM-specific autoantibodies include anti-MDA5, anti-NXP2, anti-SAE, anti-Mi-2, anti-ARS, anti-TIF1-gamma. Anti-Mi-2 antibodies are widely associated with DM cases that exhibit mainly cutaneous symptoms, such as cuticular overgrowths, Gottron's papules while being less susceptible to complications like interstitial lung disease or malignancy. The most distinct clinical features of patients with anti-SAE antibodies are their high prevalence of dysphagia and cutaneous manifestations that antecede the development of myopathies. In addition, DM patients with positive anti-PL-7 antibodies tend to have milder myositis characterized by low levels of creatine kinase as compared to patients with positive anti-Jo-1 antibodies. The anti-NXP2 antibodies are associated with transcriptional regulation and production of various proteins targeted by other DM antibodies, while anti- TIF1-γ. facilitates the transcription of deoxyribonucleic acids and regulates the growth and subsequent differentiation of body cells by controlling the signaling of TGF-β. The present review targets DM specific autoantibodies, considering their association, significance, and clinical presentation.

Livedo Racemosa, Reticulated Ulcerations, Panniculitis and Violaceous Plaques in a 46-year-old Woman

Clinically amyopathic dermatomyositis (CADM) is a subset of dermatomyositis (DM) that has conventional cutaneous manifestations of DM, but paradoxically, little or no muscle involvement. In 2005, a novel antibody was described in association with CADM – anti-melanoma differentiation-associated gene 5 (anti-MDA5). Patients with this serologic marker have a characteristic mucocutaneous phenotype consisting of skin ulceration among other signs. We describe the case of a 46-year-old woman with CADM, elevated anti-MDA5 autoantibodies, and unusual clinical features (livedo racemosa, florid acral edema) among the classical phenotype of MDA5 DM (arthralgias, ulcerations, panniculitis) and classical DM lesions (Gottron papules, heliotrope rash). The patients did not develop interstitial lung disease or internal malignancies and experienced a rapid response to prednisolone and intravenous immunoglobulins. After 2 years, she has no relapse of her cutaneous disease and continues 5 mg prednisolone and 2 g/kg kilogram of intravenous immunoglobulin every 3 months for maintenance. Our case highlights the clinical heterogeneity of CADM and underscores the importance of a comprehensive approach to DM patients. It was previously postulated that anti-MDA5 antibody could target vascular cells and compromise vascular function, the presence of livedo racemosa lesions, and MDA5 antibodies in a patient with negative thrombophilia workup, reinforce this idea. This is the first case, to our knowledge, of CADM with acral panniculitis and livedo racemosa.

Amyopathic Dermatomyositis: A Concise Review of Clinical Manifestations and Associated Malignancies

Amyopathic dermatomyositis is a rare, idiopathic, connective tissue disease that presents with dermatologic lesions of classic dermatomyositis but lacks the myopathy of this disease. Cutaneous manifestations may include Gottron's sign, heliotrope rash, and characteristic patterns of poikiloderma. There is a substantial risk for developing interstitial lung disease or malignancy in patients with amyopathic dermatomyositis. A literature review of amyopathic dermatomyositis was performed using the PubMed medical database. The key features of amyopathic dermatomyositis, including autoantibodies, clinical presentation and dermatologic manifestations, epidemiology, history, associated malignancies, management, and pathogenesis, are summarized in this review. Cancer (solid tumor) (73/79, 89 %) and hematologic malignancies (9/79, 11 %) were reported in 79 patients, with three patients having more than one malignancy. In addition, there were six patients with amyopathic dermatomyositis who had tumor of unknown primary, and eight patients with cancer-associated amyopathic dermatomyositis for whom no additional details were provided. From the group of 73 tumors for whom primary origin and sex were available, malignancy of the genitourinary organs (24/73, 33 %), aerorespiratory organs (15/73, 21 %), and breast (14/73, 19 %) were the most commonly observed solid organ tumors. Tumors of the genitourinary organs (15/48, 31 %) and breast (14/48, 29 %) were the most frequent neoplasms in women, accounting for 29 of 48 (60 %) cancers, with the most common sites being breast (14/48, 29 %), ovary (8/48, 17 %), and cervix or uterus (5/48, 10 %). In men, tumors of the aerorespiratory (9/25, 36 %) and genitourinary (9/25, 36 %) tracts were the most common neoplasms, accounting for 72 % (18/25) of cancers; the most common sites of primary malignancy were nasopharyngeal (6/25, 24 %), bladder (4/25, 16 %), and either colorectal, lung or prostate cancer (three cancers each, 12 %). In summary, the search for an undiagnosed associated malignancy in patients with amyopathic dermatomyositis should focus towards the organs most frequently affected. Similar to classic dermatomyositis, ovarian and nasopharyngeal cancers are also common in amyopathic dermatomyositis. However, in contrast to lung cancer, which is the most frequent malignancy associated with classic dermatomyositis, breast cancer was the most common type of malignancy reported in patients with amyopathic dermatomyosotis.