孫女從嬰兒時期就有異位性皮膚炎，心疼他因為癢而抓出許多血絲與常常皮膚紅腫。身為婦產科醫師的我，對這個疾病不甚了解，但最近開始閱讀這個疾病的相關知識，想與大家分享。
近二十年來，台灣的異位性皮膚炎的盛行率增加將近一倍， 有些研究顯示都市化和空氣污染會增加風險，也有些研究說媽媽在懷孕期間多吃魚會降低風險。
百分之八十的異位性皮膚炎始於5歲以下，而約有一半以上得異位性皮膚炎的小朋友，長大會”自己好” 但詳細原因不明，或許和早期疾病的控制有關。
異位性皮膚炎是一種皮膚的過敏反應，許多病人因爲皮膚天然保濕因子 (filaggrin) 不足的體質，造成過敏原更容易通過乾燥龜裂的皮膚，而誘發過敏反應，所以除了擦藥與(嚴重時)吃藥，保濕乳液對於預防復發非常重要，近幾年有些免疫阻斷劑的上市，讓對付嚴重異位性皮膚炎的 ”藥品軍火庫“ 又增加一些生力軍。
有家族病史的小朋友更容易得到異位性皮膚炎，代表基因也有關聯。約有60-70% 的異位性皮膚炎的病患，會有 Filaggrin 基因上的某些位點的突變 ，目前已知有數十個 Filaggrin 基因位點的突變，有趣的是，亞洲人與歐洲人突變的位點不盡相同。而台灣本土人口 Filaggrin 基因位點的突變，仍尚未被發表。
目前各國的皮膚科醫學會，都同意早期治療，藉以降低復發的強度與頻率，所以小朋友的皮膚如果常常乾紅癢，應該及早就醫診斷與治療。至於有家族病史但沒有發病的小朋友，是否該做Flaggrin基因檢測，而提早擦保濕乳液 ，是一個值得討論的題目。
#異位性皮膚炎
#保濕因子
#提早擦乳液
參考文獻
Chu C-Y et al. Taiwanese Dermatological Association consensus for the management of atopic dermatitis. Dermatologica Sinica. 2015 Dec 1;33(4):220–30.
Romieu I, Torrent M, Garcia-Esteban R, Ferrer C, Ribas-Fitó N, Antó JM, et al. Maternal fish intake during pregnancy and atopy and asthma in infancy. Clin Exp Allergy. 2007 Apr;37(4):518–25.
Irvine AD, McLean WHI, Leung DYM. Filaggrin mutations associated with skin and allergic diseases. N Engl J Med. 2011 Oct 6;365(14):1315–27.
Nutten S. Atopic Dermatitis: Global Epidemiology and Risk Factors. ANM. 2015;66(Suppl. 1):8–16.
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My granddaughter suffers from atopic dermatitis (AD) at a young age. The constant scratching causes little spots of bleeding and roughening of her baby skin. There doesn’t seem to be a cure for this condition. Even though I am an O&G specialist by trade, I have decided to read a little bit more on this topic and share them with you.
The prevalence of AD has doubled in Taiwan in the last 20 years. Some research shows industrialisation and air pollution may be risk factors whilst fish intake during pregnancy reduces infant risks of AD.
Eighty percent of AD starts below the age of 5. And about half of the children tend to “grow out of” AD. It may be mutli-factorial but the immune tolerance may be related to early control of AD.
Atopic dermatitis is a hypersensitivity reaction of the skin, many patients are found to have defects in their skin Filaggrin, which is a naturally-occurring skin moisturiser. Therefore skin emollient is an important treatment for the prevention of AD flares. Apart from the existing immunosuppression treatments (such as topical corticosteroids and calcineurin inhibitors), there are now biological agents available for the treatment of severe AD. The therapeutic armamentarium against AD is slowly increasing as we understand more about the disease.
Many variants of mutation at the Filaggrin gene have been found in up to 70% of patients with AD. There are currently 50-60 disease-causing variants known. Interestingly, mutations found in the European population seem to be different from those found in the Asian population. The mutations specific to the Taiwanese population are yet to be found.
The consensus amongst international experts seems to agree that early treatment of AD reduces recurrence and severities. However, it would be interesting to know the utility of early moisturizer application in those testing positive for Filaggrin gene but without AD.
