ILD Onset in MDA-5 Dermatomyositis Save

Anti–melanoma differentiation-associated gene 5 (MDA5) antibody-positive dermatomyositis (DM) is a rare, aggressive and progressive subtype of DM. Its' severity is dependent on the development of progressive interstitial lung disease (ILD), manifesting as either rapidly progressive ILD (RPILD) and chronic ILD (CILD). 

MDA-5+ RPILD carries a high mortality rate and defined by worsening dyspnea accompanied by radiographic changes within 3 months of pulmonary symptom onset. The reported study defines the time interval between ILD and MDA5+ DM diagnosis.

A retrospective, single center (University of Miami) cohort study identified adults with confirmed DM and MDA5 antibody-positive diagnoses between 2008-2023.

From a total of 774 DM patients, 14 (1.8%) were diagnosed wtih MDA5 antibody-positive DM (9 females, 5 males; mean age 48 years; 8/14 were non-Hispanic White).

RPILD was seen in 9/14 (64%) patients and 6 met RPILD criteria (43%). The time between DM diagnosis and ILD was a mean of 116 days, and a median of 163 days. There was no association between DM skin signs and ILD type. Gottron papules/sign and midfacial erythema were the most common skin findings.

While the long term outcomes of these patients was not available, RPILD patients tend to do poorly. Research has suggested that short intervals (≤1.16 months) between MDA5 antibody-positive DM and ILD diagnoses may associate with poorer prognosis.