Atopic dermatitis (AD) is a chronic relapsing inflammatory cutaneous disease that is often associated with other atopic symptoms, such as food allergy, allergic rhinitis and asthma, leading to significant morbidity and health-care costs. The pathogenesis of AD is complicated and multifactorial. Although the etiology of AD remains incompletely understood, recent studies have provided further insight into AD pathophysiology, demonstrating that the interaction among genetic predisposition, immune dysfunction, and environmental provocation factors contributes to its development. However, the increasing prevalence of AD suggests that environmental factors such as irritation and cutaneous infection play a crucial role in triggering and/or aggravating the disease. Of note, AD skin is susceptible to bacterial, fungal, and viral infections, and microorganisms may colonize the skin and aggravate AD symptoms. Overall, understanding the mechanisms by which these risk factors affect the cutaneous immunity of patients with AD is of great importance for developing a precision medicine approach for treatment. This review summarizes recent developments in exogenous factors involved in the pathogenesis of AD, with special emphasis on irritants and microbial infections.

中文翻译：

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特应性皮炎发病机制中的外源性因素：刺激物和皮肤感染

特应性皮炎 (AD) 是一种慢性复发性炎症性皮肤病，通常与其他特应性症状有关，如食物过敏、过敏性鼻炎和哮喘，导致显着的发病率和医疗费用。AD的发病机制复杂且多因素。尽管 AD 的病因仍未完全了解，但最近的研究提供了对 AD 病理生理学的进一步了解，表明遗传易感性、免疫功能障碍和环境激发因素之间的相互作用有助于其发展。然而，AD 患病率的增加表明刺激和皮肤感染等环境因素在引发和/或加重疾病方面起着至关重要的作用。值得注意的是，AD 皮肤容易受到细菌、真菌和病毒感染，微生物可能会在皮肤上定植并加重 AD 症状。总体而言，了解这些风险因素影响 AD 患者皮肤免疫的机制对于开发精准医学治疗方法具有重要意义。本综述总结了参与 AD 发病机制的外源性因素的最新进展，特别强调刺激物和微生物感染。