Magro Cynthia, Cheng Esther, Kline Mitchell A, Belsito Donald V, Goldman Barry, Varghese Mathew, Crowson A Neil, Momtahen Shabnam
Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY.
Dermatol Online J. 2020 Jul 15;26(7):13030/qt5103211m.
Psoriasis is a common autoimmune dermatosis representing an interplay between certain genetic predisposing factors along with clonally restricted Th1 T cells responding to epidermal keratinocyte derived antigen. A unique IL17/IL23 cytokine-rich milieu is pathogenetically significant and conducive to its salient histomorphologic features, such as epidermal hyperplasia and intraepidermal influx of neutrophils. The classic cutaneous manifestation is that of plaque psoriasis also referred to as psoriasis vulgaris with characteristic well-circumscribed erythematous plaques covered by silvery scales. Follicular psoriasis is an uncommon variant manifesting as a scaly folliculocentric hyperkeratotic eruption of the trunk and extremities, irrespective of the presence or absence of conventional lesions of psoriasis vulgaris. In this study we present 5 cases of follicular psoriasis, review the literature, and provide a proposal regarding relevant pathologic findings and potential pathogenetic mechanisms. The incidence of follicular psoriasis is unknown, emphasizing its rarity given the overall incidence of conventional psoriasis in the general population. Owing to the lack of awareness, this clinical presentation is often mistaken for other follicular dermatoses, including bacterial folliculitis, pityriasis rubra pilaris, keratosis pilaris, or follicular eczema.
银屑病是一种常见的自身免疫性皮肤病，表现为某些遗传易感性因素与对表皮角质形成细胞衍生抗原作出反应的克隆受限Th1 T细胞之间的相互作用。一种独特的富含IL17/IL23细胞因子的环境在发病机制上具有重要意义，并有助于其显著的组织形态学特征，如表皮增生和中性粒细胞向表皮内浸润。典型的皮肤表现为斑块状银屑病，也称为寻常型银屑病，其特征为边界清晰的红斑斑块，上面覆盖着银色鳞屑。毛囊性银屑病是一种不常见的变异型，表现为躯干和四肢以毛囊为中心的鳞屑性角化过度性皮疹，无论是否存在寻常型银屑病的传统皮损。在本研究中，我们报告了5例毛囊性银屑病病例，回顾了相关文献，并就相关病理发现和潜在发病机制提出了建议。毛囊性银屑病的发病率尚不清楚，鉴于普通人群中寻常型银屑病的总体发病率，这凸显了其罕见性。由于认识不足，这种临床表现常被误诊为其他毛囊性皮肤病，包括细菌性毛囊炎、红皮病型毛发苔藓、毛发角化病或毛囊性湿疹。
