Atopic dermatitis and covid-19 - what you need to know, including hand washing, effect on immunity and what to do if you are on immunosuppressive medication.
What is Atopic Dermatitis?
Commonly referred to as ECZEMA, Atopic Dermatitis is a genetic skin disorder characterised by allergy to a wide variety of substances which are usually harmless in the majority of people. The condition manifests itself with an extremely itchy skin and a rash in certain parts of the body viz. the elbow and knee flexures. Most patients have a positive family history of other forms of allergy ie. asthma, hay fever (sinusitis, "sinus", sneezing) and eczema.
What is the appearance of the rash of Atopic Dermatitis?
The condition usually starts in infancy between the ages of 3 and 6 months with itching and scaling of the face, scalp and trunk. In older children, the elbow and knee flexures are the main sites of involvement. In severe cases, there may be extensive involvement of the limbs and trunk with itching, scaling, excoriations and secondary infection. Dryness of the skin is common.
What is the outlook?
In a large proportion of children, the disease remits spontaneously at puberty. However, if it continues into adolescence and adult life, it enters the chronic phase with thickening of the skin in the elbow flexures and behind the knees.
What is the treatment?
It is important to realize from the outset that Atopic Dermatitis is a chronic condition, and that treatment at present is aimed at controlling the symptoms.
1. TOPICAL CORTICOSTEROIDS in the form of creams and ointments form the mainstay of treatment for the acute attack. Strong steroids eg. Diprosone, Betnovate, Advantan Fatty ointment are used for a short period of time on body areas to bring the eczema under control. Once relief is obtained, a milder steroid is then substituted eg. Elocon, Advantan, Cutivate, Procutan. The rash should be kept under control using the mildest possible steroid cream. On the face, nothing stronger than 1% hydrocortisone cream (Procutan, Dilucort) is usually necessary. Bear in mind the dangers of using strong cortisones for too long
ie. thinning of the skin, enlargement of blood vessels in the skin and development of acne.
2. TOPICAL CALCINEURIN INHIBITORS
This class includes Tacrolimus (Protopic 0.03% and 0.1%) and Pimecrolimus (Elidel). They are used when the eczema is mild. They do not steroid side effects such as thinning of the skin, hair growth and acne.
4. BATH EMOLLIENTS are also beneficial eg. Vitasure repair cream.
5. SOAPS should be restricted and emulsifying oint eg. Vitasure Repair substituted as a cleansing agent. A tablespoon dissolved in a jug of hot water and poured into the bath works well.
6. ORAL ANTIHISTAMINES are useful to suppress itching. The older sedating antihistamines eg Aterax, Phenergan, and Polarmine are of greater benefit as they allow the patient to have a good sleep in addition to the relief from itching. However, in a school going child, the newer non-sedating antihistamines often have to be used so that lack of concentration does not become a problem eg. Clarityne, Zyrtec, Telfast, Kestine and Deselex.
7. ANTIBIOTICS taken either orally or applied topically may be necessary to control secondary infection.
For extremely severe Atopic Eczema, the following forms of systemic therapies are available:
1. Narrow band UVB (Ultra violet B light)
All these drugs have side effects which necessitate their close monitoring by your dermatologist.
Localised areas of eczema may be treated with the Excimer laser which provides relief in a much shorted time compared to narrow band UVB.
While the above measures are useful in controlling acute flare-ups of the disease, one cannot underplay the importance of preventive measures in the long term control of the eczema.
Improvement in eczema within two months of starting NBUVB
The trigger factors:
1. All preservatives in foods and drinks should be avoided. Safe juices include Liquifruit, Ceres and Appletiser. Canned food should be avoided.
2. The role of dairy products and animal protein remains controversial. However, if one strongly suspects these items as exacerbating factors, an elimination diet is well worth trying, particularly if the eczema is severe, Each item eg. milk, cheese, yoghurt, peanuts, soya products and beef is avoided for about a month at a time. If there is not much difference in the severity of the eczema in that time, it would be safe to assume that that particular food item is not responsible for the flare up of the eczema.
3. There is some evidence to suggest that breast feeding in early infancy may reduce the incidence of Dermatitis in infants with a strong family history of Eczema. This is therefore to be encouraged.
4. Clothing: Cool cotton clothing should be worn. Avoid direct with wool or scratchy fabrics. Ensure that a cotton sheet is used between the skin and woolen blankets.
5. Avoid contact with irritants such as household bleaches and detergents, hair dyes, shampoos, shoe and furniture polishes.
6. Some patients are make worse with contact with dog and cat hair and with pollen.
7. Adults with Atopic Dermatitis should avoid careers which expose them to occupational irritants eg nursing and hairdressing.
OTHER TRIGGERS INCLUDE:
Long hot baths or showers
Rapid changes in temperature
Dust or sand
Food: Eggs, fish, soy, wheat
Bacterial skin infection
New treatments for Atopic Eczema
Dupilumab (Dupixent) is a new biologic soon to be released for the treatment of Atopic Dermatitis.
Dupilumab has been shown to be effective in adults with moderate to severe atopic dermatitis and provided long-term sustained benefit up to 3 years.
Dupilumab has demonstrated long term safety up to 3 years.
Dupilumab can be used in patients with atopic dermatitis with or without asthma.
New biologics in development for atopic dermatitis(not yet launched in any country)
Tralokinumab (superior to placebo and well tolerated for 52 weeks)
Nemolizumab (has shown tremendous reduction in itch)
Lebrikizumab (clinical benefits to be confirmed)
New small molecules in development for atopic dermatitis:
These have shown improvement in signs and symptoms over the short term. Risk-benefit over the long term remains to be determined.