IFIH1 and hemorrhage: We reviewed other known cases concerning anti-MDA5 Ab+ DM patients, and found only 2 previously published cases with organ bleeding.[9,12] In one case, the patient developed pneumomediastinum and intramuscular bleeding,[9] whereas in another case, diffuse alveolar damage and alveolar hemorrhage were observed by autopsy.[12] However, the mechanism responsible for organ hemorrhages in anti-MDA5 Ab+ DM cases was not determined in these previous studies.