Anti-MDA5 positive dermatomyositis associated with rapidly progressive interstitial lung disease and correlation between serum ferritin level and treatment response

Clinically amyopathic dermatomyositis is an uncommon autoimmune disorder in the Middle East. The clinical picture of clinically amyopathic dermatomyositis is characterized mainly by pulmonary and dermatological manifestations. Occasionally muscle symptoms are observed as well. Serum anti-MDA5 autoantibody positivity is associated with rapidly progressive interstitial lung disease among clinically amyopathic dermatomyositis patients. Moreover, high serum ferritin level is correlated with poor prognosis and high mortality. Herein we describe the case of an Israeli patient with rapidly progressive interstitial lung disease and without pathognomonic dermatological features who was diagnosed with anti-MDA5 positive clinically amyopathic dermatomyositis and did not survive despite immunomodulatory therapy followed by reduction in serum ferritin levels.