Yamamoto Toshiyuki
Department of Dermatology, Fukushima Medical University, Fukushima, Japan.
Open Access Rheumatol. 2015 Sep 18;7:55-62. doi: 10.2147/OARRR.S60821. eCollection 2015.
Psoriatic arthritis (PsA) is an inflammatory arthropathy associated with cutaneous psoriasis, which is currently classified as a seronegative spondyloarthropathy. The presence of cutaneous psoriasis is important for correct and early diagnosis of PsA, because the onset of cutaneous lesions usually precedes the appearance of joint manifestation. Thus, dermatologists are able to detect the condition at its inception. PsA has several unique characteristics such as enthesopathy, dactylitis, and abnormal bone remodeling. In particular, dactylitis occurs on the easily observed sites such as digits, and is thus a significant indicator of PsA. It is important to observe not only the fingers but also the toes, because dactylitis involves both digits of the hands and feet. Recently, new ideas regarding the involvement of the interleukin (IL)-23/Th17 axis have emerged, and the dramatic effects of targeting therapies have highlighted the physiological roles of key cytokines such as tumor necrosis factor-α, IL-17A, and IL-23 in psoriasis. As recent insights are shedding light on the pathogenesis of PsA, understanding of the pathogenesis of dactylitis and enthesitis are also progressing. In this article, current views on the optimal management of dactylitis are discussed.
银屑病关节炎（PsA）是一种与皮肤银屑病相关的炎性关节病，目前被归类为血清阴性脊柱关节病。皮肤银屑病的存在对于PsA的正确早期诊断很重要，因为皮肤病变的发作通常先于关节表现的出现。因此，皮肤科医生能够在疾病初期就检测到这种情况。PsA有几个独特的特征，如附着点炎、指（趾）炎和异常骨重塑。特别是，指（趾）炎发生在如手指等易于观察的部位，因此是PsA的一个重要指标。不仅要观察手指，还要观察脚趾，因为指（趾）炎累及手和脚的指（趾）。最近，关于白细胞介素（IL）-23/Th17轴参与的新观点已经出现，靶向治疗的显著效果突出了肿瘤坏死因子-α、IL-17A和IL-23等关键细胞因子在银屑病中的生理作用。随着最近的见解揭示了PsA的发病机制，对指（趾）炎和附着点炎发病机制的理解也在不断进步。在本文中，将讨论关于指（趾）炎最佳管理的当前观点。
