Clinical and histopathological features of adult patients with dermatomyositis and melanoma differentiation associated‐5 autoantibody seropositivity status, as determined by commercially available testing: a retrospective, single‐institution comparative cohort study

Abstract

Background. Although melanoma differentiation associated (MDA)-5 autoantibodies have been widely explored in dermatomyositis (DM), most studies have relied on MDA-5 autoantibody testing performed in research settings, rather than the nowavailable commercial laboratory tests. Aim. To characterize the clinical and histopathological data in patients with DM and circulating MDA-5 autoantibodies, as defined by commercially available testing. Methods. This was a retrospective review of patients with DM who underwent MDA-5 antibody testing. All available skin biopsy slides were reviewed. Results. Cutaneous features more prevalent in MDA-5-positive DM included Raynaud phenomenon (RP) (P < 0.001), cutaneous ulcerations (P = 0.01), mechanic hands (P < 0.02), palmar papules (P < 0.01), oral ulcers (P = 0.024) and alopecia (P = 0.03). Joint and pulmonary involvement were more common in patients with MDA-5-positive DM (both P < 0.001) as was dysphagia (P < 0.01). Myopathy (P = 0.4) and malignancy (P = 0.34) were not statistically different between the cohorts. Vasculopathy was more common in MDA-5-positive DM (P < 0.01), while spongiosis was less common (P < 0.02). Conclusion. This study not only confirms some known associations between disease manifestations and MDA-5 autoantibody status, as determined by commercially available tests, but also identifies new associations, including RP and dysphagia.

Predictive factors for anti‐MDA5 antibody in patients with dermatomyositis: a retrospective multicenter study

“…However, unlike previous publications, we could not establish a relationship with panniculitis, periungual involvement 12 or calcinosis, 13 but we could confirm that the presence of Raynaud's disease is rare 5 . Interestingly, other authors found a highly significant increased frequency of Raynaud's disease in association with anti‐MDA5 seropositivity, not emphasized in the literature to date 9 …”

“…There are few studies involving anti‐MDA5 + patients, our study being the one with the highest number of total cases. Other than the present study, only one was a multicenter study 9,11–14 …”

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

“…Several pieces of evidence point toward a central role of vascular injury in the pathogenesis of anti-MDA5 DM: (i) Patients frequently show typical cutaneous features such as skin ulcers due to severe vasculopathy; (ii) Histopathology of palmar papules, as well as lung tissues highlights vasculopathy ( 12 , 15 , 105 ); (iii) Biomarkers of endothelial dysfunctions have been identified in the sera of patients ( 106 , 107 ); (iv) Patients exhibited a strong IFN-I signature distributed in the vasculature of the skin ( 108 , 109 ). It is important to emphasize that these particular features are observed in the skin and the lungs of patients with anti-MDA5 DM but that there is no or few signs of vasculopathy nor of an enhanced IFN-I signature, compared to other DM, in muscle tissue of anti-MDA5 DM patients ( 21 , 22 ).…”

A Woman With Painful Digital Ulcers

“…6 Patients with MDA5-associated dermatomyositis may have typical cutaneous findings of dermatomyositis but characteristically have a distinctive phenotype that includes cutaneous and oral ulcerations and painful palmar papules; nonscarring alopecia, calcinosis, arthritis, and mechanic's hands have also been associated with this antibody. 6,7 In contrast to most patients with dermatomyositis, those with MDA5-associated dermatomyositis often do not experience proximal muscle weakness and may have normal creatine kinase and aldolase levels on blood testing. 6 In addition, MDA5-associated dermatomyositis is associated with an elevated risk of interstitial lung disease (ILD), with a reported prevalence ranging from 5% to 65%.…”