Clinical features of macrophage activation syndrome in adult dermatomyositis: A single‐center retrospective case‐control study

Abstract

BackgroundLittle is known about the features of macrophage activation syndrome (MAS) in dermatomyositis, especially the association between rapidly progressive interstitial lung disease (RP‐ILD) and MAS.ObjectiveTo determine the characteristics of MAS in patients with dermatomyositis and their association with RP‐ILD.MethodsThis was a retrospective cohort study of 201 dermatomyositis patients at the First Affiliated Hospital of Zhejiang University over a 10‐year period.ResultsA total of 22 (10.9%) patients were diagnosed with MAS. The rate of RP‐ILD was significantly higher in patients with MAS than in those without MAS (81.8% vs. 17.4%, respectively, p < .001). Multivariate analysis indicated that RP‐ILD (p = .019), ferritin level > 1685 ng/mL (p = .007) and hemoglobin < 100 g/L (p = .001) were independent risk factors for MAS. Furthermore, RP‐ILD patients with MAS presented more cardiac injury (50.0% vs. 13.3%, respectively, p < .009), central nervous system dysfunction (42.8% vs. 3.4%, respectively, p < .001) and hemorrhage (38.9% vs. 3.3%, respectively, p = .003) than RP‐ILD patients without MAS. The 90‐day cumulative survival rate for patients with MAS was significantly lower than for those without MAS (18.2% vs. 82.1%, respectively, p < .001).ConclusionMAS was a common and fatal complication of dermatomyositis in our cohort. MAS is closely related to RP‐ILD in patients with dermatomyositis. When RP‐ILD is present in dermatomyositis patients with abnormal laboratory findings, such as cytopenia and hyperferritinemia, the presence of MAS should be considered.