# Unveiling the Connections Between Melanoma Differentiation-Associated Gene 5 (MDA5)-Positive Dermatomyositis and Its Potential Association With COVID-19: A Report of Two Cases

## TL;DR

This paper reports two cases suggesting a possible link between anti-MDA5-positive dermatomyositis and exposure to COVID-19 or its vaccine.

## Contribution

It presents new clinical evidence connecting anti-MDA5 dermatomyositis with post-COVID-19 or vaccine symptoms.

## Key findings

- Two patients developed anti-MDA5-positive dermatomyositis after a COVID vaccine and subsequent infection.
- Symptoms worsened after COVID-19 infection and required aggressive treatment for disease control.
- The cases suggest a potential association between anti-MDA5 dermatomyositis and SARS-CoV-2 exposure.

## Abstract

Dermatomyositis is a rare inflammatory condition affecting the skin, muscles, and joints. This series of anti-melanoma differentiation-associated gene 5 (anti-MDA5) autoantibody-positive cases highlights a possible link between anti-MDA5-positive dermatomyositis and COVID-19 exposure. A retrospective analysis was performed on anti-MDA5-positive dermatomyositis patients at a district general hospital between January 2021 and July 2023. Information was gathered on the clinical profiles, diagnostics, management, and disease course. The two cases are as follows: (1) A 44-year-old Asian female presented with back pain, tender proximal muscles, symmetrical synovitis, and Gottron’s papules, which gradually began after a COVID vaccine and worsened after COVID-19 infection. Despite prompt management, she required finger amputation and a switch to immunomodulators to achieve arthritic disease control. (2) A 49-year-old Caucasian female presented with progressive dyspnea, polyarthralgia, dusky maculopapular rash, and oral ulcers, which began after a COVID vaccine and worsened after COVID-19 infection. Steroids and immunomodulators improved mobility and respiratory symptoms, while biologics subdued her skin symptoms. This case study provides growing evidence for an intriguing association between COVID-19 exposure and anti-MDA5 antibody-positive dermatomyositis. Further research is required to elucidate the underlying pathogenic mechanism. Early involvement of a multidisciplinary team, consideration of symptom variety, infection vigilance, and impact on quality of life are important factors for clinicians to consider when tailoring the management of these patients for optimized outcomes.