重叠胶原病或称重叠综合征是指胶原病病情的重叠概念,近年来颇受重视,已被公认是一组独立的疾病.由于其免疫学背景,不仅临床上及实验室方面具有许多新的特点,随着进一步的研究,也发现了一些新病种,如混合结缔组织病(MCTD)、硬化性皮肌炎等等,从而对其发病机理、治疗和预后提出了许多新的课题. Overlapped collagen disease or overlap syndrome refers to the concept of overlap of collagen disease, which has gained considerable attention in recent years and has been recognized as a group of independent diseases. Due to its immunological background, there are not only many new clinical and laboratory aspects With the further research, some new diseases such as mixed connective tissue disease (MCTD) and sclerosing dermatomyositis have also been found. Many new problems have been proposed for their pathogenesis, treatment and prognosis.