Department of Dermatology, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, 701-0192, Japan.
Department of Dermatology, Kawasaki General Medical Center, Kawasaki Medical School, Okayama, Okayama, Japan.
Arch Dermatol Res. 2019 Sep;311(7):555-562. doi: 10.1007/s00403-019-01937-6. Epub 2019 May 31.
Little attention has been given to the involvement of sweat glands/ducts in the pathogenesis of prurigo nodularis (PN). According to recent studies, PN is likely to develop under conditions characterized by dry skin, such as atopic dermatitis (AD), suggesting a strong impact of skin dryness on PN development. No therapeutic modalities produced complete resolution of PN without exacerbations. We previously reported that increases in skin dryness by sweating disturbance could initiate the development of AD. We investigated whether sweating responses were impaired in refractory PN lesions; and, if so, we asked whether the PN lesions could resolve by restoring sweating disturbance. Using the impression mold technique, which allows an accurate quantification of individual sweat gland/duct activity, we examined basal sweating under quiescent conditions and inducible sweating responses to thermal stimulus in PN lesions and normal-appearing skin in the same patients before and after treatment with a moisturizer or topical corticosteroids. Sweating disturbance, either basal or inducible, was most profoundly detected in the "hub" structure corresponding to the center of PN papule before the treatment. This sweating disturbance was immunohistochemically associated with the leakage of sweat into the dermis. This disturbance was restored by treatment with a moisturizer. Our limitations include a relatively small patient cohort and lack of blinding. Sweating disturbance could be one of the aggravating factors of PN development. Refractory PN with low skin hydration may resolve by restoring sweating disturbance.
人们对结节性痒疹（PN）发病机制中汗腺/导管的参与关注较少。根据最近的研究，PN 很可能在皮肤干燥的情况下发展，例如特应性皮炎（AD），这表明皮肤干燥对 PN 发展有很大的影响。没有任何治疗方法可以完全缓解 PN 而不加重病情。我们之前报告过，通过出汗障碍导致皮肤干燥增加可能会引发 AD 的发生。我们研究了在难治性 PN 病变中出汗反应是否受损；如果是这样，我们询问是否可以通过恢复出汗障碍来使 PN 病变得到缓解。我们使用压模技术，该技术可以准确量化个体汗腺/导管的活动，在治疗前后，我们检查了同一患者的 PN 病变和正常外观皮肤在静息状态下的基础出汗以及对热刺激的诱导性出汗反应，并用保湿剂或局部皮质类固醇治疗。在治疗前，“枢纽”结构（对应于 PN 丘疹的中心）中最明显地检测到基础或诱导性出汗障碍。这种出汗障碍与汗液漏入真皮有关。这种障碍通过保湿治疗得到恢复。我们的局限性包括患者队列相对较小和缺乏盲法。出汗障碍可能是 PN 发展的加重因素之一。具有低皮肤水合作用的难治性 PN 通过恢复出汗障碍可能得到缓解。
