Department of Dermatology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
Front Immunol. 2022 Mar 24;13:855408. doi: 10.3389/fimmu.2022.855408. eCollection 2022.
Dermatomyositis (DM) is an idiopathic inflammatory myopathy primarily involving skin and muscles. Clinically amyopathic dermatomyositis (CADM), a subset of DM, presents with characteristic cutaneous manifestations without clinical evidence of myositis. Although rare, vesiculobullous eruptions could develop in DM patients. Such "bullous DM" is commonly considered a sign of internal malignancy. However, some cases with similar presentations were diagnosed as autoimmune blistering disease eventually. Herein, we reported two cases of CADM with autoimmune blisters formed. Case 1 presented with vesicles and was diagnosed with CADM initially. However, this patient developed blisters again years later and was diagnosed with "pemphigus foliaceous" (PF) accordingly. Case 2, with a history of nasopharyngeal carcinoma and CADM, developed bullous pemphigoid several days after using a heat patch on her abdomen. The association between disease occurrence and local skin damage might provide more evidence to support the "epitope spreading" hypothesis. Moreover, we reviewed related literature and discussed the differences between the two disease entities in clinical presentations, pathogenesis, therapy, and the risk of complications.
皮肌炎（DM）是一种特发性炎症性肌病，主要累及皮肤和肌肉。临床无肌病性皮肌炎（CADM）是 DM 的一个亚类，表现为特征性的皮肤表现，无肌炎的临床证据。尽管罕见，但 DM 患者可能会出现水疱性皮损。这种“大疱性 DM”通常被认为是内脏恶性肿瘤的征象。然而，一些具有类似表现的病例最终被诊断为自身免疫性疱病。在此，我们报告了两例伴自身免疫性水疱形成的 CADM 病例。病例 1 表现为水疱，最初被诊断为 CADM。然而，数年后该患者再次出现水疱，被诊断为“落叶型天疱疮”（PF）。病例 2 有鼻咽癌和 CADM 病史，在腹部使用热贴数天后出现大疱性类天疱疮。疾病的发生与局部皮肤损伤之间的关联可能为“表位扩展”假说提供更多证据。此外，我们复习了相关文献，并讨论了这两种疾病实体在临床表现、发病机制、治疗和并发症风险方面的差异。
