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Case 1: primary eczema
(Posted on 2 July 2008)
Mrs. Chan's 4-year-old son has long been plagued by nagging skin problems. At the change of seasons, his skin turns red and itchy, while pimples appear around his joints. The kid cannot help but scratch, but it only makes the itchiness worsen, which may even lead to sleepless at nights.
- What is skin allergy? Does it only affect people with weak immune system?
- The doctor says my son has primary eczema. Is it a type of skin allergy?
- It is often said that beef, peanut and seafood set off skin allergy. My son has stayed away from all these. Why is he allergic still? Can mothers reduce the possibility of skin allergy of the next generation by avoiding certain food during pregnancy?
- Case 2: contact dermatitis
- What are the causes of skin allergy? How can I know my allergens?
- Are drugs mandatory to treat skin allergy? Are there any side effects with steroid?
- How can we prevent skin allergy in daily life?
Source: Quality HealthCare
What is skin allergy? Does it only affect people with weak immune system?
Skin allergy is an allergic response of the skin to the environment, while the origin of sensitive skin is a thin or damaged stratum corneum vulnerable to external stimuli.
Symptoms of skin allergy include extreme dryness of the skin, itchiness, redness, pimples, rash, blisters, inflammation, erosion and pustules. Patients may scratch their skin due to severe itchiness. That worsens the condition with inflammation and pus, perpetuating a vicious cycle.
Many wrongly attribute skin allergy to a weak immune system. However, it is an excessive response by an overly sensitive immune system, which initiates an antibody attack in the presence of only a small amount of allergens and brings about a "self-attacking" inflammatory response.
The doctor says my son has primary eczema. Is it a type of skin allergy?
Skin allergy is mainly classified intointernal/external cause.
Skin allergy due to internal cause is also known as congenital or primary eczema, including seborrhoeic dermatitis, discoid eczema, varicose eczema, asteatotic eczema as well as atopic eczema, which is the most common among children. Most cases of atopic eczema are hereditary. If the parents suffer from atopic eczema, their children are likely to suffer from symptoms early in life: persistent itchiness and superficial inflammation. Mrs. Chan's son has been diagnosed as having this type of skin allergy by the doctor.
Skin allergy due to external cause is also known as secondary eczema. Allergic response may be triggered by skin contact with certain substances (such as drugs, chemicals or metals). Such allergic contact dermatitis is characterized by rash, swelling and severe itchiness. "Housewife dermatitis" hand eczema is a kind of contact dermatitis induced by frequent contact with detergent.
It is often said that beef, peanut and seafood set off skin allergy. My son has stayed away from all these. Why is he allergic still? Can mothers reduce the possibility of skin allergy of the next generation by avoiding certain food during pregnancy?
Indiscriminate exclusion of food that may cause skin allergy does not necessarily improve the situation. It may even lead to malnutrition due to imbalanced diet. Among all precipitating factors, air is the most important source of allergens. According to research, among cases of eczema aged below 5, for instance, 90% are affected by airborne allergens and 5% food allergens; among those aged above 5, 99% are affected by airborne allergens and 1% food allergens.
Western medicine advocates targeted avoidance with evidence-based support. For example, children allergic to milk have to avoid it and opt for soy milk instead. Those with egg allergy may try to consume after age 2, when some children outgrow the allergy. Only nut allergy is a lifelong and immutable condition. Wholesale exclusion is unwise as it would compromise children's growth.
So far there has been no evidence of any causal relationship between eating habits during pregnancy and skin allergy among infants. Therefore, mothers are recommended to maintain a balanced diet for adequate nutrition to the foetus.
Case 2: contact dermatitis
Mr. Wong is a hair stylist who often comes into contact with dye and perm solutions. Lately his hands would turn itchy with rash or even blisters after each perming procedure. He does not know why, but the condition would improve when he takes leave and re-emerge when he returns. At further thought, he realizes that the salon has recently switched the supplier of dye and perm solutions.
What are the causes of skin allergy? How can I know my allergens?
There are a myriad of agents causing skin allergy, including weather, humidity, sunlight, water, plants (pollen), food, metals, chemicals, cosmetics, skin care products or perfumes. Mr. Wong's skin allergy is a case of contact dermatitis triggered by frequent contact with dye and perm solutions.
To find out your allergens, you may record the food you eat and the activities you partake every day in a diary format. Blood test is another way to test for allergens with accuracy up to 70%-80%. For patients with allergic contact dermatitis, patch test can facilitate diagnosis and locate allergens. In a patch test, suspected allergens are applied to the back of the patient and kept in place for 48 hours. Acute allergens can be detected on the third day of the test, while chronic allergens can be uncovered on the fifth day.
Are drugs mandatory to treat skin allergy? Are there any side effects with steroid?
Emollient is the key to treat skin allergy. It can protect the skin from damage and effectively control minor skin allergy. Greasy Ointment can be applied where the skin is thicker, such as the hand, while cream with higher water content should be used elsewhere, like the face. Do not put on a thick layer of emollient; a thin layer applied for multiple times during the day is the best way to go.
More severe cases can be treated by medication, either external or oral.
External: There are two types of balm for external use (steroid and non-steroid) for patients with low to medium-grade conditions. Non-steroid balm can regulate the immune system and guard against allergy for patients who have thinner skin and who do not want to receive long-term steroid treatment. Steroid is an effective agent against itchiness and inflammation, but it must be used in accordance with instructions given by the doctor. Although steroid is commonly associated with serious side effects, these are few given proper application. Steroid may also be used for children.
Oral: Oral antihistamine is a pill that alleviates itchiness and stops the vicious cycle of itch and scratch for patients with low to medium-grade conditions. Those with severe conditions may take other oral steroids or cyclosporine etc. However, long-term treatment would lead to side effects such as hypertension, high cholesterol levels and impaired kidney function. Therefore, these drugs are not prescribed by the doctor unless absolutely necessary.
How can we prevent skin allergy in daily life?
The crux of preventing skin allergy lies in the location of allergens. Allergy can be substantially reduced by staying away from allergens. In the case of Mr. Wong, dye and perm solutions are the allergens. Owing to his profession, the best he could do is to avoid direct skin contact with these materials and wear gloves at work.
Different allergies, of course, can be prevented by different ways. Generally speaking, we may focus on the following areas.
Clothing: Some kinds of skin allergy are highly sensitive to sweat and fabric. In summer, for example, you should opt for high-ventilating fabric like full cotton and refrain from nylon in order to prevent skin allergy. Avoid direct skin contact with wool in winter. Therefore, full cotton underwear is preferable with wool apparel. Quilted lining coat is another good option.
Food: Food-induced skin allergy is individualized, so wholesale exclusion of potentially allergic food is unfeasible. Once the allergen is located, the patient only has to avoid such food. Moreover, intake of preservatives, MSG and flavorings from food is inevitable in this age, and these chemicals are highly related to skin allergy. As a result, we should eat out less often and stick to a light diet.
Housing: Household hygiene is vital as airborne dust and house dust mite are major allergens. Special attention should be paid to keeping the carpet clean, while changing the bed sheets, quilts, pillow cases and curtains frequently can reduce skin allergy due to dust and house dust mite. Moreover, those allergic to animal hair should not keep cats or dogs at home.
Transport: Be mindful of the weather when you travel overseas. The skin is prone to allergic response when accommodating to weather changes. Moisturizing is essential on long-haul flights, as the dry cabin air may cause skin allergy. Remember to bring a small pack of skin care products or medicine as precaution.
Source: Quality HealthCare
