Department of Dermatology, American University of Beirut Medical Center, Beirut, Lebanon.
Indian J Dermatol Venereol Leprol. 2021 Jan-Feb;87(1):3-13. doi: 10.25259/IJDVL_638_19.
Differentiating cutaneous diseases that mimic each other clinically and histopathologically can at times be a challenging task for the dermatopathologist. At the same time, differentiation of entities with overlapping features may be crucial for patient management. Although not seen in normal skin, plasmacytoid dendritic cells usually infiltrate the skin in several infectious, inflammatory/autoimmune and neoplastic entities. Plasmacytoid dendritic cells can be identified in tissue using specific markers such as CD123 and/or blood-derived dendritic cell antigen-2. Plasmacytoid dendritic cells are the most potent producers of type I interferons and their activity may therefore be assessed indirectly in tissue using human myxovirus resistance protein A, a surrogate marker for type I interferon production. In recent years, accumulating evidence has established the utility of evaluating for specific plasmacytoid dendritic cell-related parameters (plasmacytoid dendritic cell content, distribution and clustering and/ or human myxovirus resistance protein A expression) as a diagnostic tool in differentiating cutaneous diseases with overlapping features such as the alopecias, lupus and its mimics, and neoplastic entities. In this review, we provide an update on the current evidence on this topic and on the contexts where this can be a useful adjunct to reach the histopathological diagnosis.
区分临床上和组织病理学上相互模仿的皮肤疾病有时对皮肤科病理学家来说是一项具有挑战性的任务。同时，对于患者管理而言，区分具有重叠特征的实体可能至关重要。尽管在正常皮肤中未见，但浆细胞样树突状细胞通常会浸润几种感染性、炎症/自身免疫性和肿瘤性疾病的皮肤。浆细胞样树突状细胞可以使用特异性标志物（如 CD123 和/或血液衍生的树突状细胞抗原-2）在组织中进行鉴定。浆细胞样树突状细胞是 I 型干扰素的最强产生者，因此其活性可以在组织中使用人粘病毒抗性蛋白 A（I 型干扰素产生的替代标志物）进行间接评估。近年来，越来越多的证据证实了评估特定浆细胞样树突状细胞相关参数（浆细胞样树突状细胞含量、分布和聚类和/或人粘病毒抗性蛋白 A 表达）作为区分具有重叠特征的皮肤疾病（如脱发、狼疮及其类似物和肿瘤性疾病）的诊断工具的效用。在这篇综述中，我们提供了关于该主题的最新证据以及在哪些情况下这可以作为辅助手段以达到组织病理学诊断的更新信息。
