Department of Dermatology, Institute of Medical Sciences, Medical College, Rzeszow University, 35-310 Rzeszów, Poland.
Medicina (Kaunas). 2021 Sep 27;57(10):1027. doi: 10.3390/medicina57101027.
Primary cutaneous amyloidosis (PCA) is characterized by the extracellular deposition of amyloid in the skin without systemic involvement. It comprises several clinical variants, the most common of which are macular amyloidosis (MA) and lichen amyloidosis (LA). PCA is frequently observed in Asians, while it is considered to be very rare in Caucasians. In the latter population, the condition often poses a diagnostic challenge. Dermoscopy has already been proved to be a useful, non-invasive diagnostic tool in various non-neoplastic skin diseases. In the paper, we present three Caucasian patients (skin phototypes I-II) with histologically confirmed LA. Under dermoscopy, central white hubs with grayish-brown dots and globules were observed in all three cases. Vascular structures were present in two cases and had the morphology of red globules and thick, unfocused branching lines intersecting the white hubs. A comprehensive review of the literature retrieved twelve papers presenting the dermoscopic features of PCA, including five articles on the dermoscopy of LA. The vast majority of these studies have been conducted on the Asian population, and there is a lack of data on the dermoscopic findings for patients with skin type I or II. The literature review revealed that MA and LA share several dermoscopic similarities (the presence of a white central hub and grayish dots), but also display distinct features. Compared to the dermoscopic features of LA in darker skin phototypes, our patients presented less pronounced pigmentation and more evident vascular structures. Nevertheless, further studies are needed in order to reliably evaluate the dermoscopic features of PCA in various ethnicities.
原发性皮肤淀粉样变（PCA）的特征是皮肤外分泌沉积淀粉样蛋白而无系统受累。它包括几种临床变异型，最常见的是斑状淀粉样变（MA）和苔藓样淀粉样变（LA）。PCA 在亚洲人中很常见，而在白种人中则被认为非常罕见。在后一种人群中，这种情况常常构成诊断挑战。皮肤镜已被证明是各种非肿瘤性皮肤病的有用的非侵入性诊断工具。在本文中，我们介绍了 3 例经组织学证实为 LA 的白种人患者（皮肤光型 I-II）。在皮肤镜下，所有 3 例均观察到中央白色中心有灰棕色小点和小球。在 2 例中存在血管结构，其形态为红色小球和厚而无焦点的分支线穿过白色中心。对文献进行了全面回顾，共检索到 12 篇关于 PCA 皮肤镜特征的论文，其中包括 5 篇关于 LA 皮肤镜的论文。这些研究绝大多数是在亚洲人群中进行的，缺乏关于 I 型或 II 型皮肤患者皮肤镜表现的数据。文献回顾显示，MA 和 LA 具有一些相似的皮肤镜特征（存在白色中央中心和灰色小点），但也具有不同的特征。与深色皮肤光型的 LA 的皮肤镜特征相比，我们的患者表现出较不明显的色素沉着和更明显的血管结构。然而，需要进一步的研究以便能够可靠地评估不同种族 PCA 的皮肤镜特征。
