Clinical Characteristics, Management, and Outcomes of Patients with MDA5-associated Rapidly Progressive Interstitial Lung Disease: A Single-center Observational Study from Qatar

Background: Melanoma differentiation-associated protein 5 (MDA5) dermatomyositis (DM; MDA5-DM) is a distinct subtype of DM often complicated by rapidly progressive interstitial lung disease (RP-ILD) and high mortality. Although the prevalence of anti-MDA5 antibodies among idiopathic inflammatory myopathies may reach 30%, data from the Middle East remains limited. Objectives: This study aimed to describe the clinical features, management strategies, and outcomes of patients with MDA5-DM associated RP-ILD from a tertiary care center in Qatar. Materials and Methods: We conducted a retrospective observational study of all patients with DM evaluated at a tertiary care center in Qatar between January 2021 and December 2024. Patients aged more than 18 years and with confirmed MDA5-associated RP-ILD were included in the study. Demographic, clinical, serological, and outcome data were retrieved retrospectively from electronic medical records. The patients were followed for 1–3 years, with a mean follow-up duration of approximately 90 weeks. Results: Ten patients were identified (80% male; median age: 41 years). Common cutaneous manifestations included ulceration, inverse Gottron’s sign, and mechanic’s hands. Arthritis was present in 80% of cases, and clinically evident myopathy in 60%. Anti-Ro52 positivity was observed in 80%. Serum ferritin correlated with disease activity (mean peak: 2849 ng/L). All patients received high-dose corticosteroids; 70% were treated with intravenous immunoglobulin and rituximab, 50% were treated with tacrolimus, 30% were treated with cyclophosphamide, and 30% were treated with mycophenolate mofetil. Three patients died of respiratory failure despite combination therapy, whereas seven survived following early aggressive treatment. Survivors were followed for 1–3 years (mean: 90 weeks), with no recurrence of symptoms reported. Conclusions: MDA5-associated RP-ILD is an aggressive and often fatal condition. Early recognition and intensive multidrug immunosuppressive therapy appear crucial for improving the survival of the patients.