Abstract: Lu Jinghao, Liu Chaofan, Zhou Xing, Hu Dongyan, Xin Chongmei, Zhu Lubing, Li Ming Department of Dermatology, Zhongshan Hospital, Fudan University, Shanghai 200032, China Corresponding author: Zhu Lubing, Email: zhu.lubing@ zs-hospital.sh.cn 【Abstract】 Objective To firstly report 4 cases of dermatomyositis characterized by painful palmar eruptions complicated by fatal rapidly progressive interstitial lung disease （RP-ILD） in China. Methods Four patients with dermatomyositis with painful palmar eruptions complicated by fatal RP-ILD were enrolled from the Department of Dermatology, Zhongshan Hospital, Fudan University between December 2014 and April 2017, and their clinical and pathological features were analyzed. Results Among these patients, 3 were female and 1 was male. Their age ranged from 47 to 59 years. Of the 4 patients, 3 had no muscular involvement. All of the 4 patients had multiple solid red papules or nodules on the bilateral palms, palmar and lateral surfaces of fingers, which preceded, followed or concurred with the onset of other skin lesions of dermatomyositis. The occurrence of typeⅠrespiratory failure was preceded by 3 weeks to 5 months of painful palmar eruptions in the 4 patients. Early-stage palmar eruptions were easily misdiagnosed as contact dermatitis, eczema or erythema multiforme. Histopathological examination of the skin lesions on the finger palmar surface showed perivascular in?ltration of a few lymphocytes in the dermis, and deposition of varying amounts of mucin-like substances around blood vessels and appendages. Of the 4 patients, 3 showed positive staining for anti-melanoma differentiation-associated gene 5 antibody. Although the 4 patients received anti-inflammatory and immunosuppressive therapies, they all finally died of respiratory failure. Conclusions Dermatomyositis with painful palmar eruptions may indicate the occurrence of fatal RP-ILD, and early biopsy of skin lesions is needed to help to identify the disease. Immunosuppressive treatment should be performed timely to improve the prognosis in these patients.

Key words: Dermatomyositis, Lung diseases, interstitial, Skin manifestations, Hand, Pain, Glucocorticoids, Immunosuppressive agents