Humphreys F, Spencer J, Mclaren K, Tidman M J
Department of Dermatology, University of Edinburgh, UK.
Clin Exp Dermatol. 1996 Jan;21(1):17-19.
The 'dirty neck' appearance is a characteristic disorder of pigmentation, which has previously been found to affect approximately 2% of adult atopics. This disorder results in a rippled pattern of hyperpigmentation similar to that seen in macular amyloidosis. Biopsy specimens from affected skin of three patients were examined by histological and electron microscopical techniques. In addition to eczematous changes, marked pigmentary incontinence was observed. Amyloid-like material was detected by electron microscopy but not by light microscopy in all three specimens. Some deposition of amyloid occurs in this condition but the pigmentary changes are attributable to melanin incontinence. In 1987, two separate groups, Manabe et al. and Colver et al., described a distinctive type of hyperpigmentation, found particularly on the neck in some patients with chronic atopic eczema. Manabe's group found that 1.7% of 700 patients with atopic eczema showed this clinical characteristic, and that only adolescents and adults were affected. This condition has been called the 'dirty neck' appearance or 'ripple pigmentation of the neck in atopic dermatitis'. The clinical features are a rippled pattern of hyperpigmentation seen particularly on the anterior and lateral aspects of the neck (Fig. 1). We have also observed the same appearance in the inguinal areas. A number of factors could contribute to the development of hyperpigmentation in chronic atopic eczema. It is possible that the 'dirty neck' appearance is a form of post-inflammatory pigmentation due to previous eczema, ultraviolet exposure or even the application of photosensitizing products, and that the rippled appearance is related to the cutaneous anatomy of the neck. The pathogenesis of the 'dirty neck' is obscure, but in common with previous authors, we have noted that the rippled appearance of the hyperpigmentation resembles that seen in macular amyloidosis. In order to determine whether deposition of amyloid contributes to the development of this type of pigmentation in atopic dermatitis, an histological and ultrastructural examination of skin biopsies from three patients with the condition was undertaken.
“脏脖子”外观是一种色素沉着的特征性病症，此前发现约2%的成年特应性皮炎患者受其影响。这种病症会导致色素沉着出现波纹状，类似于斑状淀粉样变所见。对3例患者受累皮肤的活检标本进行了组织学和电子显微镜检查。除了湿疹样改变外，还观察到明显的色素失禁。所有3个标本经电子显微镜检测到淀粉样物质，但光学显微镜未检测到。在这种情况下会发生一些淀粉样物质沉积，但色素变化归因于黑素失禁。1987年，Manabe等人和Colver等人两个独立的研究小组描述了一种独特的色素沉着类型，尤其在一些慢性特应性皮炎患者的颈部发现。Manabe的研究小组发现，700例特应性皮炎患者中有1.7%表现出这种临床特征，且仅青少年和成年人受累。这种情况被称为“脏脖子”外观或“特应性皮炎患者颈部的波纹状色素沉着”。临床特征是色素沉着呈波纹状，尤其见于颈部的前侧和外侧（图1）。我们在腹股沟区域也观察到了相同的外观。多种因素可能导致慢性特应性皮炎中色素沉着的发生。“脏脖子”外观可能是既往湿疹、紫外线暴露甚至使用光敏产品所致的炎症后色素沉着的一种形式，且波纹状外观与颈部的皮肤解剖结构有关。“脏脖子”的发病机制尚不清楚，但与之前的作者一样，我们注意到色素沉着的波纹状外观类似于斑状淀粉样变所见。为了确定淀粉样物质沉积是否促成了特应性皮炎中这种色素沉着类型的发生，对3例患有该病患者的皮肤活检标本进行了组织学和超微结构检查。
