Time to Lung Disease in Patients With Dermatomyositis Subtype Estimated

TOPLINE:

The time interval between onset of interstitial lung disease (ILD) and diagnosis of anti–melanoma differentiation-associated gene 5 (MDA5) antibody-positive dermatomyositis (DM) “has not been well described,” the authors say.

METHODOLOGY:

• MDA5 antibody-positive DM is a rare DM subtype associated with ILD, which is categorized into rapidly progressive ILD (RPILD) and chronic ILD, with the former having a particularly high mortality rate.
• In this retrospective cohort study using electronic medical records, researchers evaluated 774 patients with DM between 2008 and 2023 to learn more about the time interval between ILD and the time of an MDA5 antibody-positive DM diagnosis, which has not been well described.
• The primary outcome was ILD diagnosis and time in days between documented ILD and MDA5 antibody-positive DM diagnoses.

TAKEAWAY:

• Overall, 14 patients with DM (1.8%) were diagnosed with MDA5 antibody-positive DM in dermatology, rheumatology, or pulmonology departments (nine women and five men; age, 24-77 years; 79% were White and 7% were Black).
• ILD was diagnosed in 9 of the 14 patients (64%); 6 of the 14 (43%) met the criteria for RPILD. Two cases were diagnosed concurrently and two prior to MDA5 antibody-positive DM diagnosis.
• The median time between ILD and MDA5 antibody-positive DM diagnoses was 163 days.
• Gottron papules/sign and midfacial erythema were the most common dermatologic findings, and no association was seen between cutaneous signs and type of ILD.

IN PRACTICE:

“Establishing an accurate timeline between MDA5 antibody-positive DM and ILD can promote urgency among dermatologists to evaluate extracutaneous manifestations in their management of patients with DM for more accurate risk stratification and appropriate treatment,” the authors wrote.

SOURCE:

This study, led by Rachel R. Lin, from the University of Miami, Miami, Florida, was published online as a research letter in JAMA Dermatology.

LIMITATIONS:

Study limitations were the study’s retrospective design and small sample size.

DISCLOSURES:

No information on study funding was provided. One author reported personal fees from argenX outside this submitted work. Other authors did not disclose any competing interests.

A version of this article appeared on Medscape.com.