{"id":596,"date":"2026-08-17T15:24:53","date_gmt":"2026-08-17T07:24:53","guid":{"rendered":"https:\/\/eczema.skinmedical.com.hk\/cause\/"},"modified":"2026-08-17T17:01:05","modified_gmt":"2026-08-17T09:01:05","slug":"cause","status":"publish","type":"page","link":"https:\/\/eczema.skinmedical.com.hk\/en\/cause\/","title":{"rendered":"Cause and Types"},"content":{"rendered":"<div class=\"vce-row-container\" data-vce-boxed-width=\"true\"><div class=\"vce-row vce-row--col-gap-30 vce-row-equal-height vce-row-content--top\" id=\"el-87d545d5\" data-vce-do-apply=\"all el-87d545d5\"><div class=\"vce-content-background-container\"><\/div><div class=\"vce-row-content\" data-vce-element-content=\"true\"><div class=\"vce-col vce-col--md-66-66p vce-col--xs-1 vce-col--xs-last vce-col--xs-first vce-col--sm-last vce-col--sm-first vce-col--md-last vce-col--lg-last vce-col--xl-last vce-col--md-first vce-col--lg-first vce-col--xl-first\" id=\"el-34face20\"><div class=\"vce-col-inner\" data-vce-do-apply=\"border margin background  el-34face20\"><div class=\"vce-col-content\" data-vce-element-content=\"true\" data-vce-do-apply=\"padding el-34face20\"><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-e7fd0fce\" data-vce-do-apply=\"all el-e7fd0fce\"><h3><span style=\"color: #808080;\">Cause and types<\/span><\/h3>\r\n<\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><div class=\"vce-row-container\" data-vce-boxed-width=\"true\"><div class=\"vce-row vce-row--col-gap-30 vce-row-equal-height vce-row-content--top\" id=\"el-679c18e8\" data-vce-do-apply=\"all el-679c18e8\"><div class=\"vce-row-content\" data-vce-element-content=\"true\"><div class=\"vce-col vce-col--md-auto vce-col--xs-1 vce-col--xs-last vce-col--xs-first vce-col--sm-last vce-col--sm-first vce-col--md-last vce-col--lg-last vce-col--xl-last vce-col--md-first vce-col--lg-first vce-col--xl-first\" id=\"el-85f4bfca\"><div class=\"vce-col-inner\" data-vce-do-apply=\"border margin background  el-85f4bfca\"><div class=\"vce-col-content\" data-vce-element-content=\"true\" data-vce-do-apply=\"padding el-85f4bfca\"><div class=\"vce vce-separator-container vce-separator--align-center vce-separator--style-solid\" id=\"el-4b3d282a\" data-vce-do-apply=\"margin el-4b3d282a\"><div class=\"vce-separator vce-separator--color-bfc0c1 vce-separator--width-100 vce-separator--thickness-1\" data-vce-do-apply=\"border padding background  el-4b3d282a\"><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><div class=\"vce-row-container\" data-vce-boxed-width=\"true\"><div class=\"vce-row vce-row--col-gap-30 vce-row-equal-height vce-row-content--top\" id=\"el-089dd853\" data-vce-do-apply=\"all el-089dd853\"><div class=\"vce-content-background-container\"><\/div><div class=\"vce-row-content\" data-vce-element-content=\"true\"><div class=\"vce-col vce-col--md-22-12p vce-col--xs-1 vce-col--xs-last vce-col--xs-first vce-col--sm-last vce-col--sm-first vce-col--md-first vce-col--lg-first vce-col--xl-first\" id=\"el-7799ea8c\"><div class=\"vce-col-inner\" data-vce-do-apply=\"border margin background  el-7799ea8c\"><div class=\"vce-col-content\" data-vce-element-content=\"true\" data-vce-do-apply=\"padding el-7799ea8c\"><div class=\"vce-single-image-container vce-single-image--align-center\"><div class=\"vce vce-single-image-wrapper\" id=\"el-6c773e96\" data-vce-do-apply=\"all el-6c773e96\"><figure><div class=\"vce-single-image-figure-inner\" style=\"width: 400px;\"><div class=\"vce-single-image-inner vce-single-image--absolute\" style=\"width: 100%; padding-bottom: 66.75%;\"><img loading=\"lazy\" decoding=\"async\" class=\"vce-single-image\"  width=\"400\" height=\"267\" srcset=\"https:\/\/eczema.skinmedical.com.hk\/wp-content\/uploads\/2024\/05\/photo-1586282091736-c2f9a8af8772-320x214.jpg 320w, https:\/\/eczema.skinmedical.com.hk\/wp-content\/uploads\/2026\/08\/photo-1586282091736-c2f9a8af8772-400x267.jpg 400w\" src=\"https:\/\/eczema.skinmedical.com.hk\/wp-content\/uploads\/2026\/08\/photo-1586282091736-c2f9a8af8772-400x267.jpg\" data-img-src=\"https:\/\/eczema.skinmedical.com.hk\/wp-content\/uploads\/2024\/05\/photo-1586282091736-c2f9a8af8772.jpg\" data-attachment-id=\"312\"  alt=\"\" title=\"\" \/><\/div><\/div><figcaption hidden=\"\"><\/figcaption><\/figure><\/div><\/div><\/div><\/div><\/div><div class=\"vce-col vce-col--md-77-86p vce-col--xs-1 vce-col--xs-last vce-col--xs-first vce-col--sm-last vce-col--sm-first vce-col--md-last vce-col--lg-last vce-col--xl-last\" id=\"el-9904d78f\"><div class=\"vce-col-inner\" data-vce-do-apply=\"border margin background  el-9904d78f\"><div class=\"vce-col-content\" data-vce-element-content=\"true\" data-vce-do-apply=\"padding el-9904d78f\"><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-b598d20e\" data-vce-do-apply=\"all el-b598d20e\"><h3><strong><span style=\"color: #756464;\"><span style=\"color: #756464;\">What causes atopic dermatitis?<\/span><\/span><\/strong><\/h3><p>&nbsp;<\/p><p><span style=\"color: #756464;\"><span style=\"font-size: 15pt;\">There is no single cause. The condition arises where genetic susceptibility meets environment.<\/span><\/span><\/p><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><div class=\"vce-row-container\" data-vce-boxed-width=\"true\"><div class=\"vce-row vce-row--col-gap-30 vce-row-equal-height vce-row-content--top\" id=\"el-4d7f2ac0\" data-vce-do-apply=\"all el-4d7f2ac0\"><div class=\"vce-content-background-container\"><\/div><div class=\"vce-row-content\" data-vce-element-content=\"true\"><div class=\"vce-col vce-col--md-auto vce-col--xs-1 vce-col--xs-last vce-col--xs-first vce-col--sm-last vce-col--sm-first vce-col--md-last vce-col--lg-last vce-col--xl-last vce-col--md-first vce-col--lg-first vce-col--xl-first\" id=\"el-2987cdc3\"><div class=\"vce-col-inner\" data-vce-do-apply=\"border margin background  el-2987cdc3\"><div class=\"vce-col-content\" data-vce-element-content=\"true\" data-vce-do-apply=\"padding el-2987cdc3\"><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-394e0c25\" data-vce-do-apply=\"all el-394e0c25\"><p><span style=\"color: #756464;\">\u2022 <strong>Genetics.<\/strong> A family history of eczema, asthma or allergic rhinitis is the strongest single predictor. Risk factors include a family history of eczema, asthma and allergic rhinitis, along with increased exposure to allergens such as those in soaps, bleaches and dyes, or occupational wet work.<\/span><br><span style=\"color: #756464;\">\u2022 <strong>Barrier gene variants<\/strong>, filaggrin being the best characterised.<\/span><br><span style=\"color: #756464;\">\u2022 <strong>Immune dysregulation<\/strong> \u2014 the type 2 inflammatory response described above.<\/span><br><span style=\"color: #756464;\">\u2022 Skin microbiome disturbance. Staphylococcus aureus colonises the majority of eczematous skin and worsens inflammation, even without frank infection.<\/span><br><span style=\"color: #756464;\">\u2022 <strong>Environment.<\/strong> Low humidity, air conditioning, heat and sweat, hard water, soaps and detergents, wool and rough fabrics, dust mite exposure, and air pollution.<\/span><br><span style=\"color: #756464;\">\u2022 <strong>Stress and sleep deprivation<\/strong>, which are both consequence and trigger.<\/span><\/p><\/div><\/div><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-ea963126\" data-vce-do-apply=\"all el-ea963126\"><p><span style=\"color: #756464;\"><strong>Common triggers to identify individually<\/strong>: heat and sweating (a major factor in the Hong Kong climate), soaps and bubble baths, fragrance, wool, dust mite, pet dander, low-humidity air-conditioned environments, upper respiratory infections, and emotional stress. Triggers differ between individuals \u2014 which is why a trigger diary is more useful than a generic avoidance list.<\/span><\/p><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><div class=\"vce-row-container\" data-vce-boxed-width=\"true\"><div class=\"vce-row vce-row--col-gap-10 vce-row-equal-height vce-row-content--top\" id=\"el-fff3bd30\" data-vce-do-apply=\"all el-fff3bd30\"><div class=\"vce-content-background-container\"><\/div><div class=\"vce-row-content\" data-vce-element-content=\"true\"><div class=\"vce-col vce-col--md-auto vce-col--xs-1 vce-col--xs-last vce-col--xs-first vce-col--sm-last vce-col--sm-first vce-col--md-last vce-col--lg-last vce-col--xl-last vce-col--md-first vce-col--lg-first vce-col--xl-first\" id=\"el-0cf9185d\"><div class=\"vce-col-inner\" data-vce-do-apply=\"border margin background  el-0cf9185d\"><div class=\"vce-col-content\" data-vce-element-content=\"true\" data-vce-do-apply=\"padding el-0cf9185d\"><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-7b4aab15\" data-vce-do-apply=\"all el-7b4aab15\"><h3>Types and patterns<\/h3>\r\n<\/div><\/div><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-cd940fbf\" data-vce-do-apply=\"all el-cd940fbf\"><p>Atopic dermatitis is one condition with several recognisable presentations. Classification is by age pattern, morphology and severity rather than by discrete \"types.\"<\/p>\r\n<\/div><\/div><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-87bc8ec8\" data-vce-do-apply=\"all el-87bc8ec8\"><h3><span style=\"font-size: 18pt;\"><strong><span style=\"color: #756464;\">By age<\/span><\/strong><\/span><\/h3>\r\n<div align=\"left\">\r\n<table class=\"fr-table-selection-hover\" style=\"border-collapse: collapse; width: 93%; margin-right: calc(7%); border: medium none currentcolor;\">\r\n<tbody>\r\n<tr>\r\n<td style=\"color: #efefef; background-color: #efefef; border: 0.75pt solid #c4c7c5; width: 22.7629%;\"><span style=\"color: #756464; font-size: 16px;\"><strong><span style=\"font-family: 'Google Sans', sans-serif;\">Age group\/span&gt;<\/span><\/strong><\/span><\/td>\r\n<td style=\"color: #efefef; background-color: #efefef; border: 0.75pt solid #c4c7c5; width: 38.0967%; text-align: center;\"><span style=\"color: #756464; font-size: 16px;\"><strong><span style=\"font-family: 'Google Sans', sans-serif;\">Typical distribution<\/span><\/strong><\/span><\/td>\r\n<td style=\"color: #efefef; background-color: #efefef; border: 0.75pt solid #c4c7c5; text-align: center; width: 39.1577%;\"><span style=\"color: #756464; font-size: 16px;\"><strong><span style=\"font-family: 'Google Sans', sans-serif;\">Typical appearance<\/span><\/strong><\/span><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"border: 0.75pt solid #c4c7c5; width: 22.7629%;\"><span style=\"color: #756464; font-size: 16px;\"><span style=\"font-family: 'Google Sans', sans-serif;\">Infantile (0\u20132 years)<\/span><\/span><\/td>\r\n<td style=\"border: 0.75pt solid #c4c7c5; width: 38.0967%; text-align: center;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Cheeks, forehead, scalp, outer limbs, trunk. Nappy area usually spared.<\/span><\/td>\r\n<td style=\"border: 0.75pt solid #c4c7c5; text-align: center; width: 39.1577%;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Red, weeping, crusted patches. Very itchy; infants rub against bedding.<\/span><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"border: 0.75pt solid #c4c7c5; width: 22.7629%;\"><span style=\"color: #756464; font-size: 16px;\"><span style=\"font-family: 'Google Sans', sans-serif;\">Childhood (2\u201312 years)<\/span><\/span><\/td>\r\n<td style=\"border: 0.75pt solid #c4c7c5; width: 38.0967%; text-align: center;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Flexures \u2014 elbow creases, behind the knees, wrists, ankles, neck.<\/span><\/td>\r\n<td style=\"border: 0.75pt solid #c4c7c5; text-align: center; width: 39.1577%;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Drier, thicker, more scaly. Lichenification begins.<\/span><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"border: 0.75pt solid #c4c7c5; width: 22.7629%;\"><span style=\"color: #756464; font-size: 16px;\"><span style=\"font-family: 'Google Sans', sans-serif;\">Adolescent \/ adult<\/span><\/span><\/td>\r\n<td style=\"border: 0.75pt solid #c4c7c5; width: 38.0967%; text-align: center;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Flexures, hands, eyelids, face and neck, upper trunk.<\/span><\/td>\r\n<td style=\"border: 0.75pt solid #c4c7c5; text-align: center; width: 39.1577%;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Thickened, leathery, lichenified. Hand eczema often dominates.<\/span><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"border: 0.75pt solid #c4c7c5; width: 22.7629%;\"><span style=\"color: #756464; font-size: 16px;\"><span style=\"font-family: 'Google Sans', sans-serif;\">Elderly-onset<\/span><\/span><\/td>\r\n<td style=\"border: 0.75pt solid #c4c7c5; width: 38.0967%; text-align: center;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Often more widespread, less flexural<\/span><\/td>\r\n<td style=\"border: 0.75pt solid #c4c7c5; text-align: center; width: 39.1577%;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Marked dryness, sometimes nummular pattern<\/span><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<\/div><\/div><div class=\"vce vce-separator-container vce-separator--align-center vce-separator--style-solid\" id=\"el-0a1d6018\" data-vce-do-apply=\"margin el-0a1d6018\"><div class=\"vce-separator vce-separator--color-bfc0c1 vce-separator--width-60 vce-separator--thickness-1\" data-vce-do-apply=\"border padding background  el-0a1d6018\"><\/div><\/div><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-8c77eb34\" data-vce-do-apply=\"all el-8c77eb34\"><h3><strong><span style=\"color: #756464; font-size: 18pt;\">By morphology<\/span><\/strong><\/h3><p><span style=\"color: #756464;\"><strong>Nummular (discoid)<\/strong> - coin-shaped, well-defined plaques, often on the limbs. Frequently mistaken for fungal infection.<\/span><br><span style=\"color: #756464;\"><strong>Follicular<\/strong> - small itchy bumps centred on hair follicles. This pattern is more common in Chinese and other Asian patients and is often missed, because it does not look like textbook eczema.<\/span><br><span style=\"color: #756464;\"><strong>Prurigo-type<\/strong> - firm, intensely itchy nodules from chronic scratching.<\/span><br><span style=\"color: #756464;\"><strong>Hand and foot eczema<\/strong> - may be the only site in adults, and is strongly aggravated by occupational wet work.<\/span><br><span style=\"color: #756464;\"><strong>Head-and-neck predominant<\/strong> - in adults, this pattern raises the question of Malassezia sensitivity.<\/span><\/p><\/div><\/div><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-2585768a\" data-vce-do-apply=\"all el-2585768a\"><p><span style=\"color: #756464;\"><strong>A point specific to Asian skin.<\/strong> Atopic dermatitis in Chinese and other East Asian patients more often shows well-demarcated, thickened, scaly plaques that can look psoriasis-like, alongside a greater tendency to follicular accentuation. There is also a much higher risk of <strong>post-inflammatory hyperpigmentation<\/strong> \u2014 the brown marks left after a patch settles. These marks are not scars, they fade over months, and they respond to controlling the inflammation rather than to lightening creams. Patients are frequently more distressed by the pigmentation than by the eczema itself, and this deserves to be addressed directly rather than dismissed.<\/span><\/p><\/div><\/div><div class=\"vce vce-separator-container vce-separator--align-center vce-separator--style-solid\" id=\"el-5043a4d9\" data-vce-do-apply=\"margin el-5043a4d9\"><div class=\"vce-separator vce-separator--color-bfc0c1 vce-separator--width-60 vce-separator--thickness-1\" data-vce-do-apply=\"border padding background  el-5043a4d9\"><\/div><\/div><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-133850ae\" data-vce-do-apply=\"all el-133850ae\"><h3><strong><span style=\"color: #756464; font-size: 18pt;\">By severity<\/span><\/strong><\/h3><p><span style=\"color: #756464;\"><br>Severity is graded using validated tools \u2014 SCORAD, EASI, and the patient-reported POEM and DLQI. These matter because they convert \"it's quite bad\" into a number that can be tracked, and because access to advanced therapy usually requires documented severity.<br><\/span><\/p><div align=\"left\"><table class=\"fr-table-selection-hover\" style=\"border-collapse: collapse; width: 93%; margin-right: calc(7%); border: medium none currentcolor;\"><tbody><tr><td style=\"color: #efefef; background-color: #efefef; border: 0.75pt solid #c4c7c5; width: 13.7454%;\"><span style=\"color: #756464; font-size: 16px;\"><strong><span style=\"font-family: 'Google Sans', sans-serif;\">Severity<\/span><\/strong><\/span><\/td><td style=\"color: #efefef; background-color: #efefef; border: 0.75pt solid #c4c7c5; width: 86.2546%; text-align: center;\"><span style=\"color: #756464; font-size: 16px;\"><strong><span style=\"font-family: 'Google Sans', sans-serif;\">Rough description<\/span><\/strong><\/span><\/td><\/tr><tr><td style=\"border: 0.75pt solid #c4c7c5; width: 13.7454%;\"><span style=\"color: #756464; font-size: 16px;\"><span style=\"font-family: 'Google Sans', sans-serif;\">Mild<\/span><\/span><\/td><td style=\"border: 0.75pt solid #c4c7c5; width: 86.2546%; text-align: center;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Dry skin, infrequent itch, small areas<\/span><\/td><\/tr><tr><td style=\"border: 0.75pt solid #c4c7c5; width: 13.7454%;\"><span style=\"color: #756464; font-size: 16px;\"><span style=\"font-family: 'Google Sans', sans-serif;\">Moderate<\/span><\/span><\/td><td style=\"border: 0.75pt solid #c4c7c5; width: 86.2546%; text-align: center;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Frequent itch, visible redness, disturbed sleep, larger areas<\/span><\/td><\/tr><tr><td style=\"border: 0.75pt solid #c4c7c5; width: 13.7454%;\"><span style=\"color: #756464; font-size: 16px;\"><span style=\"font-family: 'Google Sans', sans-serif;\">Severe<\/span><\/span><\/td><td style=\"border: 0.75pt solid #c4c7c5; width: 86.2546%; text-align: center;\"><span style=\"color: #756464; font-size: 16px; font-family: 'Google Sans', sans-serif;\">Widespread, continuous itch, significantly disturbed sleep, marked impact on daily life<\/span><\/td><\/tr><\/tbody><\/table><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div><div class=\"vce-row-container\" data-vce-boxed-width=\"true\"><div class=\"vce-row vce-row--col-gap-30 vce-row-equal-height vce-row-content--top\" id=\"el-d00b0faa\" data-vce-do-apply=\"all el-d00b0faa\"><div class=\"vce-content-background-container\"><\/div><div class=\"vce-row-content\" data-vce-element-content=\"true\"><div class=\"vce-col vce-col--md-auto vce-col--xs-1 vce-col--xs-last vce-col--xs-first vce-col--sm-last vce-col--sm-first vce-col--md-last vce-col--lg-last vce-col--xl-last vce-col--md-first vce-col--lg-first vce-col--xl-first\" id=\"el-e2af4738\"><div class=\"vce-col-inner\" data-vce-do-apply=\"border margin background  el-e2af4738\"><div class=\"vce-col-content\" data-vce-element-content=\"true\" data-vce-do-apply=\"padding el-e2af4738\"><div class=\"vce-text-block\"><div class=\"vce-text-block-wrapper vce\" id=\"el-7b5cdf49\" data-vce-do-apply=\"all el-7b5cdf49\"><p><span style=\"color: #756464; font-size: 12pt;\">Reference:<\/span><\/p>\r\n<ol>\r\n \t<span style=\"color: #756464; font-size: 12pt;\">\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Davis DMR, Drucker AM, Alikhan A, et al. AAD guidelines of care for the management of atopic dermatitis in adults with topical therapies. J Am Acad Dermatol. 2023.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Sidbury R, Alikhan A, Bercovitch L, et al. AAD guidelines of care for the management of atopic dermatitis in adults with phototherapy and systemic therapies. J Am Acad Dermatol. 2023.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Guidelines Development Panel of the Hong Kong College of Paediatricians. Management of Atopic Dermatitis in Children: 2020 Review. HK J Paediatr. 2021;26:42-57. \u2014 the key local reference; cite this prominently.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Wollenberg A, Kinberger M, Arents B, et al. EuroGuiDerm guideline on atopic eczema. J Eur Acad Dermatol Venereol. (most recent update).<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">National Institute for Health and Care Excellence. Atopic eczema in under 12s: diagnosis and management. CG57.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Leung R, Wong G, Lau J, et al. Prevalence of asthma and allergy in Hong Kong schoolchildren: an ISAAC study. Eur Respir J 1997.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Childhood Wheeze, Allergic Rhinitis, and Eczema in Hong Kong: ISAAC Study from 1995 to 2015. \u2014 source of the 21-year local trend data.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Severity scoring of atopic dermatitis: the SCORAD index. Consensus Report of the European Task Force on Atopic Dermatitis. Dermatology 1993;186:23-31.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Efficacy and Safety of Lebrikizumab in Combination With Topical Corticosteroids in Adolescents and Adults With Moderate-to-Severe Atopic Dermatitis: A Randomized Clinical Trial (ADhere). JAMA Dermatol.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">ARCADIA 1 and ARCADIA 2 \u2014 two identically designed pivotal phase III trials enrolling more than 1,700 patients, evaluating nemolizumab administered subcutaneously every four weeks versus placebo with background topical corticosteroids.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Sanofi. Press release: decision not to submit amlitelimab in atopic dermatitis for global regulatory reviews. Paris, 24 July 2026.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Simpson EL, Bieber T, Guttman-Yassky E, et al. Two Phase 3 Trials of Dupilumab versus Placebo in Atopic Dermatitis (SOLO 1 and SOLO 2). N Engl J Med. 2016.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Chalmers JR, et al. BEEP trial: daily emollient during the first year of life for preventing atopic dermatitis. Lancet. 2020. \u2014 the negative prevention trial cited in the article.<\/span><\/li>\r\n<li><span style=\"color: #756464; font-size: 12pt;\">Hong Kong Drug Office, Department of Health \u2014 verify local registration status of every systemic agent named.<\/span><\/li>\r\n<\/span><\/ol>\r\n<\/div><\/div><\/div><\/div><\/div><\/div><\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Cause and types What causes atopic dermatitis?&nbsp;There is no single cause. The condition arises where genetic susceptibility meets environment.\u2022 Genetics. A family history of eczema, asthma or allergic rhinitis is the strongest single predictor. Risk factors include a family history of eczema, asthma and allergic rhinitis, along with increased exposure to allergens such as those&hellip; <a class=\"more-link\" href=\"https:\/\/eczema.skinmedical.com.hk\/en\/cause\/\">Continue reading <span class=\"screen-reader-text\">Cause and Types<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-596","page","type-page","status-publish","hentry","entry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.2 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Cause and Types<\/title>\n<meta name=\"description\" content=\"What causes atopic dermatitis? There is no single cause. The condition arises where genetic susceptibility meets environment. 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