Most dermatitis falls into one of the two following categories:
Atopic dermatitis (also known as eczema) tends to affect the face and skin creases of about 15% of infants and young children. The affected areas (e.g: behind the knee, inside the elbow) tend to be very dry and itchy. Scratching is a common problem – it can lead to further itchiness, broken skin and skin infections.
Atopic dermatitis is often made worse by:
The cause is unknown and there is no permanent cure. However, it can usually be controlled with appropriate advice and treatment. It generally improves with time. Most children grow out of it but it can recur, particularly if the skin is exposed to irritants later in life.
This form of dermatitis is often caused by repeated contact with detergents, skin cleansers, acids or alkalis, solvents or other products. Such contact eventually dries the skin and breaks down its protective layers. Irritant contact dermatitis usually affects the hands.
Certain occupations which involve exposure to irritants as an everyday part of the job can make people more prone to this type of dermatitis. Irritant contact dermatitis is particularly high amongst nurses and hairdressers (soaps, hot water, shampoos), builders and cleaners (solvents) and motor mechanics. People who work in these types of jobs and who have had atopic dermatitis should also be aware of the risk of flare-ups.
This form of contact dermatitis is much less common. It affects people who become over-sensitised (allergic) to contact – even very occasionally – with certain everyday substances. This differs from irritant contact dermatitis where regular contact with a range of irritants is the problem.
When you touch a substance you are allergic to, your body's immune system reacts to form a rash at the point of contact (usually the hands). This rash may spread, making it difficult to know where it started and what caused it. Only substances you have an allergy to will cause this. Allergies to nickel in jewellery, latex in rubber gloves, clothing elastic, medical strapping and plasters are quite common.
Causes of dermatitis include:
The cause of a rash or scaly patch may not be obvious, so letting your doctor make a proper diagnosis is the first step. You may need to try a cream or medication, have a skin test for allergies or have skin or nail scrapings taken to test for other (secondary) infections.
Ways to treat dermatitis include:
Hydrocortisone is a weak corticosteroid. There are many stronger ones that require much more care. You may be given more than one cream. If so, make sure you understand how to use each one, and:
Ask for specific instructions on how to use your topical steroid(s): which one? where? when? how often, and for how long?
By carefully avoiding irritants and substances causing allergy, looking after your overall health, taking medications as advised by your doctor and products to keep your skin moist (moisturisers), soft and supple (emollients), you can help improve and protect your skin.
Dermatitis is often a long term problem. If your skin tends to be dry, try to avoid excessive bathing and soaps (they are alkaline and the perfumes in them can irritate your skin). Soap substitutes (eg, aqueous cream) can be used instead, and adding oatmeal or tar-based pine oil products to your bathwater may relieve itchy skin.
Emollients or moisturisers are an important core treatment as they help maintain the skin’s protective barrier function (keeping moisture in and irritants out). They also prevent dry skin and the inflammation that can lead to a flare up of the rash.
For allergic dermatitis, finding the substance causing the allergy and avoiding it is the only real cure. Your doctor can arrange for you to have specific allergy tests if the substance causing it is not obvious.
If your dermatitis is caused by household or workplace irritants, you may not be able to avoid them. Using barrier creams or gloves may help protect your skin.
Dermatitis DermNet New Zealand
Eczema Allergy New Zealand
Source: Health Navigator