Department of Dermatology Integrated Medicine, Graduate School of Medicine Osaka University, Japan.
Allergol Int. 2011 Sep;60(3):387-91. doi: 10.2332/allergolint.10-CR-0265. Epub 2011 Feb 25.
We report four adult cases of atopic dermatitis (AD) complicated by Sjögren's syndrome (SS). The patients fulfilled diagnostic criteria for AD and SS. All cases showed persistent itchy dry skin and eczematous lesions complicated by sicca symptoms including dry eyes and dry mouth with moderate joint pain. One case manifested annular erythema and another manifested widespread discoid erythema. To investigate the underlying cause of dry skin in these cases, sweating function was evaluated using a quantitative sudomotor axon reflex test (QSART) in which the axon reflex is stimulated by acetylcholine iontophoresis. The sweating latency time was significantly prolonged in eczematous skin of AD and AD/SS compared to normal controls. Axon reflex (AXR) sweat volume was also significantly reduced in AD (normal and eczematous skin) and AD/SS (normal and eczema) compared to normal control. In contrast, the direct sweat volume of lesional or non-lesional AD skin induced by direct stimulation with acetylcholine was only slightly reduced compared to that in normal controls, but not in SS and lesional skin of AD/SS patients. These results suggest that the impaired sweat response in AD is attributable to an abnormal sudomotor axon reflex, which is accelerated and modulated when complicated by SS resulting in dry skin in the present cases.
我们报告了 4 例特应性皮炎（AD）并发干燥综合征（SS）的成年病例。这些患者均符合 AD 和 SS 的诊断标准。所有病例均表现为持续瘙痒的干燥皮肤和湿疹性皮损，伴有干燥眼和口干等干燥症状，以及中度关节痛。1 例表现为环状红斑，另 1 例表现为广泛盘状红斑。为了探讨这些病例皮肤干燥的潜在原因，我们使用定量自主神经反射试验（QSART）评估了出汗功能，其中轴突反射通过乙酰胆碱离子电渗刺激。与正常对照组相比，AD 和 AD/SS 的湿疹皮肤的出汗潜伏期明显延长。与正常对照组相比，AD（正常和湿疹皮肤）和 AD/SS（正常和湿疹）的轴突反射（AXR）汗量也明显减少。相比之下，AD 皮损或非皮损皮肤直接用乙酰胆碱刺激诱导的直接汗量仅略低于正常对照组，但 SS 患者和 AD/SS 皮损皮肤则没有。这些结果表明，AD 中受损的汗液反应归因于自主神经轴突反射异常，当并发 SS 时，轴突反射加速和调节，导致本病例皮肤干燥。
