For a study, it was determined that Anti–melanoma differentiation-associated protein 5 (MDA5) autoantibodies had been linked to an increased risk of interstitial lung disease (ILD) and rapidly progressive ILD (RP-ILD) in patients with dermatomyositis (DM). However, data on these factors in Latin American patients was sparse. Patients with classic DM (CDM) and clinically amyopathic DM (CADM) from 3 Latin American nations were included in the medical records review cohort research (Argentina, Brazil, and Mexico).

A total of 270 diabetic patients were assessed, with CADM accounting for 25.9% and CDM accounting for 74.1%. The total prevalence of ILD and RP-ILD was 70 (25.9%), and 4 (1.5%) of the 270 patients, respectively, and the distributions were comparable across CDM and CADM patients. Anti-MDA5 antibodies were found in 31 (25.4%) of 122 patients with CDM and 17 (48.6%) of 35 CADM patients; it was not linked with ILD or RP-ILD. Anti-MDA5–positive patients with CDM, on the other hand, had a substantially higher frequency of “mechanic’s hands,” arthralgia, arthritis, and lower blood creatine phosphokinase levels, whereas anti-MDA5–positive CADM patients had a significantly higher frequency of arthritis. The most common causes of mortality in diabetic patients were pulmonary infection and ILD.

In contrast to the relatively low frequency of RP-ILD, the prevalence of ILD in patients with DM in the research was equivalent to that stated in the literature. Furthermore, anti-MDA5 was not related to ILD or RP-ILD, although anti-MDA5–positive patients with DM had symptoms similar to the antisynthetase syndrome. The leading causes of mortality in the sample were pulmonary infection and ILD.