ABSTRACT
Objective To investigate the clinical features of polymyositis/dermatomyositis (PM/DM) with anti-nuclear matrix protein (anti-2NXP2) antibodies in Han-Chinese.Methods ImmunoprecipitationWestern Blotting (IP-WB) method was used for screening anti-NXP2 antibodies in 141 adult Han-Chinese patients with PM/DM.The clinical and laboratory data were collected,analyzed and compared with the antiNXP2-positive patients reported in the literature.Statistical analyses were performed using chi-square test and Fisher's exact test.Results Seven (5％) patients,including 6 with DM and 1 with PM,were identified as anti-NXP2 positive.Consistent with the 114 anti-NXP2-positive patients reported in the literature,Han patients with anti-NXP2 had higher frequencies of weakness,heliotrope rash and Gottron's sign.Compared with anti-NXP2-negative patients,anti-NXP2-positive patients presented significantly higher frequencies of dysphagia [43％(3/7) vs 9％(12/134),x2=8.04,P=0.027] and edema [43％(3/7) vs 2％(3/134),x2=26.94,P=0.001 4],while an absence of PM/DM related cancer was observed in Han patients with anti-NXP2.Conclusion Adult Han-Chinese patients with anti-NXP2 are DM predominant,and are characterized by a high frequencies of edema and dysphagia.