Dermatomyositis Which Was Double Positive for Anti-MDA5 and Anti-ARS Antibodies That Was Successfully Treated by Intensive Immunosuppressive Therapy

Successful treatment with tofacitinib for relapse of rapidly progressive interstitial lung disease in anti-melanoma differentiation-associated gene 5 antibody-positive clinically amyopathic dermatomyositis

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody is associated with clinically amyopathic dermatomyositis (CADM) with rapidly progressive interstitial lung disease (RP-ILD). Recently, several studies have reported that tofacitinib (TOF), a Janus kinase inhibitor, might be effective for cases of new or refractory RP-ILD in anti-MDA5 antibody-positive CADM; however, it is unknown whether TOF can also be effective for relapsed cases. We herein report a relapsed case of RP-ILD in anti-MDA5 antibody-positive CADM, which was successfully treated by combination therapy with TOF (5 mg twice daily). Our case suggests that TOF may also be a potential treatment option for relapsed cases of this disease.

The clinical features and prognoses of anti-MDA5 and anti-aminoacyl-tRNA synthetase antibody double-positive dermatomyositis patients

Objective

To explore the clinical features and prognoses of dermatomyositis (DM) associated with a double-positive anti-MDA5 and anti-aminoacyl-tRNA synthetase (anti-ARS) antibody presentation.

Methods

We retrospectively analyzed 1280 consecutive patients with idiopathic inflammatory myopathy (IIM). Individuals with anti-MDA5 and anti-ARS antibodies (anti-MDA5+/ARS+) were compared to anti-MDA5-/ARS+ and anti-MDA5+/ARS- control individuals based on clinical, pulmonary radiological characteristics, treatment, and follow-up information.

Results

Six individuals (0.47%) presented with anti-MDA5+/ARS+; of these, 2 (33.3%) were anti-PL-12+, 2 (33.3%) were anti-Jo-1+, 1 (16.7%) was anti-EJ+, and 1 (16.7%) was anti-PL-7+. Hallmark cutaneous manifestations, including Gottron’s sign (100%), heliotrope rash (50%), mechanic’s hand (66.7%), and skin ulcers (16.7%) were common. Anti-MDA5+/ARS+ patients tended to have higher ferritin levels (p = 0.038) than anti-MDA5-/ARS+ group, and higher CD4+ T-cell counts (p = 0.032) compared to the anti-MDA5+/ARS- group. Radiologically, NSIP with OP overlap was predominant (60%). Consolidation (60%), ground-glass attenuation (GGA) (80%), traction bronchiectasis (80%), and intralobular reticulation (100%) were common in anti-MDA5+/ARS+ individuals. All were diagnosed with ILD and 50% were categorized as RPILD. All patients received glucocorticoids combined with one or more immunosuppressants. Most (83.3%) had a good prognosis following treatment, but there was no difference in the survival rate between the three subgroups.

Conclusion

Presentation with anti-MDA5+/ARS+ DM was rare. The clinical and radiological characteristics of anti-MDA5+/ARS+ DM combined the features of anti-MDA5+ and anti-ARS+ individuals. Individuals with anti-MDA5+/ARS+ antibodies may respond well to glucocorticoid therapy; glucocorticoids combined with one or more immunosuppressants may be considered a basic treatment approach.