Allergy and Immunology Unit, University of Cape Town Lung Institute, Cape Town, South Africa.
School of Public Health and Family Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
Pediatr Allergy Immunol. 2021 Jul;32(5):1013-1021. doi: 10.1111/pai.13476. Epub 2021 Mar 16.
Environmental exposures are involved in the pathogenesis of the allergic phenotype and in determining which individual triggers a person becomes sensitized to. Atopic dermatitis (AD) may modulate these effects through increased penetration through the skin modifying the immune system and AD may be triggered or intensified by environmental exposures. These exposures and immune-modulating factors may differ in urban and rural environments.
To compare house dust composition in urban and rural settings and correlate them with AD outcomes.
Dust samples were collected from the beds of 156 children aged 6 months to 3 years. 42% of participants had atopic dermatitis. Samples were analyzed for bacterial endotoxin, fungal (β-1,3-glucan) levels, and house dust mite, cockroach, dog, cat, mouse, and peanut allergen. Exposures were compared in urban and rural environments and in participants with and without AD.
Endotoxin but not fungal β-glucan exposure is higher in the environment of healthy controls than children with AD in both urban and rural settings. House dust mite allergen exposure is high in urban and rural settings with Dermatophagoides detected in 100% of samples. Cat and dog allergen exposure mirrors pet ownership patterns which differ slightly between groups and environments. Mouse allergen exposure is higher in urban homes.
Environmental endotoxin may be protective against AD in both urban and rural settings. There are marked differences in allergen exposure in urban and rural settings, but these are unlikely to be important protective or risk factors.
环境暴露与过敏表型的发病机制有关，并决定了个体对哪些物质致敏。特应性皮炎（AD）可能通过增加皮肤通透性来调节这些影响，从而改变免疫系统，并且 AD 可能会被环境暴露所触发或加剧。这些暴露和免疫调节因素在城市和农村环境中可能存在差异。
比较城市和农村环境中的室内灰尘成分，并将其与 AD 结果相关联。
从 156 名 6 个月至 3 岁的儿童的床上收集灰尘样本。42%的参与者患有特应性皮炎。对细菌内毒素、真菌（β-1,3-葡聚糖）水平以及屋尘螨、蟑螂、狗、猫、鼠和花生过敏原进行了分析。在城市和农村环境中以及在有和没有 AD 的参与者中比较了暴露情况。
在城市和农村环境中，健康对照组的环境中内毒素暴露高于 AD 患儿，但真菌β-葡聚糖暴露则相反。屋尘螨过敏原在城市和农村环境中均有较高暴露，在 100%的样本中检测到了屋尘螨。猫和狗过敏原的暴露与宠物拥有模式相吻合，在不同组和环境中略有差异。城市家庭中的鼠过敏原暴露较高。
环境内毒素可能对城市和农村环境中的 AD 具有保护作用。城市和农村环境中过敏原暴露存在显著差异，但这些差异不太可能是重要的保护或风险因素。
