1. Causes and Treatment of Atopic Dermatitis
14 September 2010
Causes and Treatment of Atopic Dermatitis
Dong Seok Cha, Ph.D.
Department of Oriental Pharmacy
College of Pharmacy
Woosuk University

2. Contents Characteristic of Atopic Dermatitis (AD) Causes of AD
Treatment of AD
Prevention of AD
Definition
Symptom
Genetic factor
Environmental factor
Immune system imbalance
Dysfunction of skin barrier
Avoiding allergens
Drug treatment
Phototherapy
Alternative Treatment

3. Characteristic of Atopic Dermatitis

4. What is Atopic Dermatitis?
Atopy or atopic syndrome
= allergic hypersensitivity
Dermatitis
= inflammation of the skin
Atopic Dermatitis (AD)
A type of eczema
Non-contagious
Often begins in childhood and may persist into adulthood.
Occurs together with other atopic diseases

5. Prevalence Rate of Atopic Dermatitis

6. Symptoms of Atopic Dermatitis

7. Causes of Atopic Dermatitis

8. Causes of Atopic Dermatitis
Genetic factor
Environmental factor
Immune system imbalance
Dysfunction of skin barrier

9. Causes of AD – Genetic Factor
Family history is very important
The inheritance pattern is complex
AD genetics involve several genes, each with a different function
- IgE response related gene
- skin barrier function related gene
- skin inflammation related gene
Genetic mutation of the epidermal barrier protein, filaggrin is one predisposing factor for atopic dermatitis
Effect of genetics
Numerous studies have confirmed the role of genetic factors in the development of atopic dermatitis. They have shown that atopic dermatitis is a genetic disorder based on the interactions of unknown number of genes and environmental factors. In a family with a child affected by atopic dermatitis, there is generally a family history of eczema or any of the other atopic diseases; asthma and rhinitis.
The inheritance pattern is more complex and does not follow the Mendelian pattern. Parental atopy (parents with allergies) carries the highest risk factor. An atopic mother is a higher risk factor than an atopic father. This can be explained by stronger maternal genetic heritability, shared physical environment of mother and child, or environmental events that affect the fetus in utero.
In one study of all atopic diseases, a stronger correlation was found between siblings than between siblings and parents, indicating that environmental factors, especially during childhood, may be responsible for increased incidence of atopic dermatitis. The identification of parental genes may be of great help in studying the pathogenesis of atopic dermatitis.
Atopic dermatitis is often accompanied by asthma and hay fever. A multifactorial cause for atopic dermatitis has been suggested, with genetic and environmental factors influencing disease development.
However, genetic studies on atopic dermatitis show, interestingly, that the suspected gene regions of high risk identified show little overlap with the suspected gene regions of asthma suggesting a strong possibility that different sets of genes may be responsible for these two atopic diseases. Instead, some of the identified regions overlap with suspected regions for psoriasis, another chronic skin disease. The implication being, those genes in the skin involved in psoriasis might be playing an important role in atopic dermatitis pathogenesis. Genetic mutation of the epidermal barrier protein, called, filaaggrin is one predisposing factor for atopic dermatitis, but there are many more unkown genes involved.
One important suspected region is on a chromosome, whose genes are involved in the regulation of epidermal differentiation. Recent genetic studies have identified a cluster of genes on the outermost layer of the skin which may be as important as those which modify atopic dermatitis. Identification of the responsible genes would be of enormous help in diagnosis and treatment of the disease.
To summarize, atopic dermatitis genetics are complex and appear to involve several genes, each with a different function. Some relate to immunoglobin E response, some to the skin barrier function and some to skin inflammation.
However, there are still gaps in our knowledge about gene–environment interactions, better studies of the natural history of atopic dermatitis

10. Causes of AD – Genetic Factor
Effect of genetics
Numerous studies have confirmed the role of genetic factors in the development of atopic dermatitis. They have shown that atopic dermatitis is a genetic disorder based on the interactions of unknown number of genes and environmental factors. In a family with a child affected by atopic dermatitis, there is generally a family history of eczema or any of the other atopic diseases; asthma and rhinitis.
The inheritance pattern is more complex and does not follow the Mendelian pattern. Parental atopy (parents with allergies) carries the highest risk factor. An atopic mother is a higher risk factor than an atopic father. This can be explained by stronger maternal genetic heritability, shared physical environment of mother and child, or environmental events that affect the fetus in utero.
In one study of all atopic diseases, a stronger correlation was found between siblings than between siblings and parents, indicating that environmental factors, especially during childhood, may be responsible for increased incidence of atopic dermatitis. The identification of parental genes may be of great help in studying the pathogenesis of atopic dermatitis.
Atopic dermatitis is often accompanied by asthma and hay fever. A multifactorial cause for atopic dermatitis has been suggested, with genetic and environmental factors influencing disease development.
However, genetic studies on atopic dermatitis show, interestingly, that the suspected gene regions of high risk identified show little overlap with the suspected gene regions of asthma suggesting a strong possibility that different sets of genes may be responsible for these two atopic diseases. Instead, some of the identified regions overlap with suspected regions for psoriasis, another chronic skin disease. The implication being, those genes in the skin involved in psoriasis might be playing an important role in atopic dermatitis pathogenesis. Genetic mutation of the epidermal barrier protein, called, filaaggrin is one predisposing factor for atopic dermatitis, but there are many more unkown genes involved.
One important suspected region is on a chromosome, whose genes are involved in the regulation of epidermal differentiation. Recent genetic studies have identified a cluster of genes on the outermost layer of the skin which may be as important as those which modify atopic dermatitis. Identification of the responsible genes would be of enormous help in diagnosis and treatment of the disease.
To summarize, atopic dermatitis genetics are complex and appear to involve several genes, each with a different function. Some relate to immunoglobin E response, some to the skin barrier function and some to skin inflammation.
However, there are still gaps in our knowledge about gene–environment interactions, better studies of the natural history of atopic dermatitis

11. Causes of AD – Environmental Factor
Industrialization
Hygiene hypothesis
Dietary life
Food allergy
Trans fat
Residential Environment
Aeroallergens
eg. dust mites, pollens, animal danders
VOCs
eg. formaldehyde, benzene
산업화가 잘 이루어진 나라에서 아토피 발병률 높음 -> 아프리카 난민 아토피??
Sick building syndrome

12. Causes of AD - Immune System Imbalance
Th1
Th2
[Homeostatic state]
Th2
Th1
hygiene hypothesis 위생가설
Th1
Th2
[Cell-mediated Immunity]
[Allergy / Atopy]

13. Causes of AD - Immune System Imbalance

14. Causes of AD – Dysfunction of Skin Barrier
TEWL
Allergen
Irritant
Chronic Stage of AD
Skin Barrier Function
Ceramide
The skin of people with atopic dermatitis loses its moisture holding capacity and becomes dry. A dry skin is a poor barrier to germs. The condition becomes difficult to control when certain factors make the skin still drier. These include winters (cold, dry air), frequent washing with very hot water, soaps and antiseptics, low humidity, and high temperatures. Regular use of emollients may help in reducing the dryness.
피부위에서 수분이 증발되는 양을 TEWL(TRANS-EPIDERMAL WATER LOSS)

15. Treatment of Atopic Dermatitis

16. Treatment of Atopic Dermatitis
Treatment for Atopic Dermatitis has multidimensional aims
Improving the skin barrier function
Reducing the inflammation
Identifying the responsible triggers
Preventing any secondary infection
Common treatment options for AD
- Avoiding allergens
Drug treatment
Phototherapy
Alternative therapy
The skin of people with atopic dermatitis loses its moisture holding capacity and becomes dry. A dry skin is a poor barrier to germs. The condition becomes difficult to control when certain factors make the skin still drier. These include winters (cold, dry air), frequent washing with very hot water, soaps and antiseptics, low humidity, and high temperatures. Regular use of emollients may help in reducing the dryness.
피부위에서 수분이 증발되는 양을 TEWL(TRANS-EPIDERMAL WATER LOSS)

17. Treatment of AD – Avoiding Allergens
Discovering the triggers of allergic reactions
Learning to avoid them.
아토피 치료법이 없으므로 일차적 치료방법은 알러겐 제거가 우선이다 (예방개념)

18. Treatment of AD – Drug Treatment
Topical Treatment
- Emollient (moisturizer)
- Topical corticosteroids
- Topical calcineurin inhibitors
eg. Pimecrolimus and Tacrolimus
- Topical antimicrobial therapy
- Coal tar
Systemic Treatment
- Antihistamines
- Corticoteroids
- Immunomodulators
eg. Azathioprine
- Antimicrobials
Topical treatments focus on reducing both
the dryness and inflammation of the skin.

19. Treatment of AD – Recent Drugs Being Tested for AD
Corticosteroids, immunosuppressants have serious side effects
AD imposes tremendous social and financial costs on patients
Improved drugs are necessary
Leukotriene antagonist
Monoclonal antibodies
Topical treatments focus on reducing both
the dryness and inflammation of the skin.
Leflunomide
Recombinant interferon-gamma

20. Treatment of AD – Phototherapy
Ultraviolet (UV) light therapy
Works as an anti-inflammatory agent
Various type of UV
- Psoralen plus UVA (PUVA)
- A combination of broadband UVB/UVA light treatment
- Broadband UVA exposure
- Broad-band UVB exposure
- Narrowband UVB ( nm)
- UVA-1 ( nm)
Side effects
- stinging, burning, ageing of the skin, pigmentation
- risk of squamous cell carcinoma and melanoma.
Topical treatments focus on reducing both
the dryness and inflammation of the skin.

21. Treatment of AD – Alternative Therapy
Currently, the level of interest in alternative treatments continues to increase
Traditional herbal medicine formulation
External application
Combined internal and external treatment
Merit
Demerit
Reducing corticosteroid usage
Prescribed differently for each patient
Less side effect
Unique flavor
Regulation of immune responses
Herbal allergens
Synergic effect
Expensive
소풍산, 보중익기탕, 계지복령환, 황련해독탕, 가미소요산, 오령산, 당귀작약산,
In Traditional Chinese Medicine, AD is called “wet sore” and belongs to the syndrome type of Dampness – Heat infusion. The therapeutic principles include removing dampness, strengthening the spleen and dispelling pathogenic wind and dampness. The herbs used in the TCHM have functions of clearing heat, removing dampness and strengthening the spleen.

22. Prevention of Atopic Dermatitis

23. Prevention of Atopic Dermatitis
Diet
Mental health
care
Skin care
Lifestyle
소풍산, 보중익기탕, 계지복령환, 황련해독탕, 가미소요산, 오령산, 당귀작약산,
In Traditional Chinese Medicine, AD is called “wet sore” and belongs to the syndrome type of Dampness – Heat infusion. The therapeutic principles include removing dampness, strengthening the spleen and dispelling pathogenic wind and dampness. The herbs used in the TCHM have functions of clearing heat, removing dampness and strengthening the spleen.

24. Thank you for your attention