Atopic dermatitis
Atopic dermatitis is a relapsing eczematous condition seen more commonly in infants and children. Approximately 50% of patients develop this condition by the first year of life and additional 30% develop it within 1-5 years. Initially, it was thought that these children would outgrow this eczema by adolescence; however due to changes in our lifestyle, atopic dermatitis is seen in adults as well.
Causes
History of atopic dermatitis amongst family members and allergy are considered to be two main causes of this disease. Unlike other diseases, urbanisation and improved quality of life has contributed to increased incidences of eczema as it has been found that when children are exposed to allergens in childhood, the skin gets used to it and does not react violently to them. Hence, exaggerated care/over-protection of children against dust can predispose them to develop this disease.
Children with early onset of atopic dermatitis can develop allergic rhinitis or asthma at a later age.
Risk factors
Factors which aggravate atopic dermatitis are -
- Dry skin
- Long, hot baths or showers
- Stress
- Excessive sweating
- Rapid changes in temperature
- Low humidity
- Solvents, cleaners, soaps or detergents
- Wool or man-made fabrics or clothing
- Dust or sand
- Smoking
- Urbanisation
- Certain foods such as eggs, milk, fish, soy or wheat, shell-fish, etc.
Symptoms
Eczema may affect any area of your skin, but it typically appears on the arms and behind the knees. It tends to flare-up periodically and then subsides. Excessive itching and redness of the skin are the main symptoms observed.
The skin condition can be divided into 3 phases based on some characteristic clinical features: infantile, childhood and adulthood phases. However, exact categorisation may be difficult at times due to overlapping features and they often do not follow the sequential evolution.
In infants, the cheeks and perioral areas (near the lips) are affected first due to the dripping of saliva and smearing of liquid foods on these areas. As the infant starts crawling, the eczematous process tends to get localised to the hands and legs.
Itching may be intermittent but becomes worse by evening and night. Vigorous scratching can lead to abrasions on the skin and thickening at that particular area. Small, raised bumps may also appear which leak fluid and form crust when scratched.
Diagnosis
There is no diagnostic test for atopic dermatitis. However, it is found that the serum IgE levels are elevated in such patients. A blood count can be done to check their eosinophil cell count.
Phadiatop test can be done to determine to what the patient’s body is allergic to and those allergens should be completely avoided.
A lot of skin diseases like psoriasis, ichthyosis, seborrheic dermatitis, etc resemble atopic dermatitis. Hence, parents should visit a dermatologist when such symptoms appear.
Treatment
There is no complete cure for atopic dermatitis. A systemic, prolonged approach must be used to keep the disease in control. Firstly, avoid or eliminate aggravating factors. This can be easily done by following a few instructions such as:
- Always wear full-sleeved clothes in evening and while going to sleep.
- Always wear cotton clothes. In winters, wear woollens on top of cotton clothes.
- Completely avoid wearing synthetic clothes.
- Avoid carpets in the house.
- Keep the house clean and dust-free as much as possible. When the house is being cleaned, the patient should be out of the house so that he does not come in contact with dust.
- Avoid playing in grass as pollens are known to aggravate the disease.
- Avoid foods which can aggravate the condition.
- Always use a moisturising soap while taking bath.
- Learn to cope with stress by practising meditation, yoga, etc.
Pharmacological treatments depend on the severity of the disease.
In mild cases, adequate hydration of the skin with moisturisers along with use of mild corticosteroids like fluticasone, desonide is adequate.
In moderate to severe cases, along with moisturisers, moderate-high potent steroids may be used to control the flare. Immunosuppressants like tacrolimus and pimecrolimus are used as a ‘last line defence’ in the treatment of severe atopic dermatitis instead of, or in addition to traditional corticosteroid creams.
In severe cases that do not respond to other treatments, oral immunosuppressant medications such as cyclosporin, azathioprine and methotrexate are prescribed. However these medicines should be taken under complete medical supervision. Also, immunotherapy against specific allergens has been found to be useful in the treatment.
Complications
Patients with this skin condition often have the following:
- Viral infections (herpes simplex), bacterial infections and fungal infections.
- Eyelid dermatitis (blepharitis), allergic conjunctivitis, keratoconjunctivitis, etc.
- Hand eczema
- Psychological problems like depression are commonly observed.