Vietnam France Hospital in Hanoi has recently introduced a Patch Test service to help patients identify the causes of skin inflammation and allergies.
In response to the increasing demand for allergy diagnostics, Vietnam France Hospital in Hanoi is offering a comprehensive Patch Test service to assist clients in determining the underlying causes of skin inflammation and allergies.
This service is particularly beneficial for patients suffering from atopic dermatitis, such as eczema, urticaria, and neurodermatitis, improving their quality of life.
Currently, Vietnam France Hospital in Hanoi is implementing this testing method, which includes: an initial consultation and examination with a dermatologist, allergy testing, and two follow-up consultations with a dermatologist.
After undergoing the Patch Test, clients will receive a list of allergens to avoid (related to allergic contact dermatitis), along with medical advice to help prevent the recurrence of troublesome skin conditions.
What is a Patch Test?
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Testing for skin inflammation causes with Patch Test (Image: bio-diagnostics) |
Patch Test is a diagnostic method used to identify causes of inflammation due to skin contact.
This test involves applying pre-prepared allergens to healthy skin, with each allergen placed in a specific location. After 48 or 96 hours, if there is any sign of allergic reaction upon contact with a particular allergen, it is identified as the cause of the condition.
An allergen is a substance that can cause allergic reactions on the skin. These substances can be found in medications, cosmetics, and various industries such as leather production, tobacco, rubber, and others.
Who should undergo this test?
Most people can benefit from this test, as knowing which allergens trigger their reactions allows them to better protect their skin.
This is especially important for individuals who frequently experience allergies without a known cause, patients with atopic dermatitis (eczema, urticaria, neurodermatitis, etc.); those who regularly come into contact with cosmetics, especially women who use various beauty products and jewelry; and individuals working in the chemical industry should consider undergoing a Patch Test.
The skin – the body’s protective system
The skin protects the body from harmful environmental factors, with two barriers: the stratum corneum and the basement membrane. Damage to the stratum corneum increases the skin’s permeability, leading to excessive water loss through the epidermis. Chemicals can easily penetrate the skin, gradually depleting its protective and restorative functions. The inevitable result is skin inflammation.
Contact dermatitis depends on various factors such as the concentration of the contact substance, methods of exposure, duration of contact, the area of contact, age, individual sensitivity, skin condition, race, and other factors such as weather conditions (hot, humid, cold) and increased sweating. Generally, darker skin is less sensitive than lighter skin. Dry or damaged skin increases susceptibility to allergens. Girls aged 12-16 often show sensitivity to nickel in jewelry. Young adults may develop contact dermatitis from cosmetics or occupational exposure, while older adults typically experience it due to medication use.
What is contact dermatitis?
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Skin affected by urticaria (Image: VNN) |
Contact dermatitis is a skin inflammatory reaction due to interaction between the skin and external agents. It is the body’s response to foreign factors that cause allergies. Based on the mechanism of the disease, contact dermatitis is classified into two types: allergic and irritant.
Irritant contact dermatitis (inflammatory reaction caused by exposure to irritants) is usually caused by alkaline or acidic substances and by certain insects with high toxicity. It causes inflammation without the body’s immune response and accounts for approximately 80% of cases.
Allergic contact dermatitis occurs only in individuals with an allergic predisposition. The allergens must trigger an immune response from the body. This is a delayed type of allergy – mediated by cellular mechanisms. Allergic contact dermatitis typically represents about 20% of cases.
Symptoms of contact dermatitis
When the skin comes into contact with irritants, symptoms may include: tingling sensations, burning, dry and tight skin. More severe reactions include redness, swelling, followed by the appearance of vesicles, blisters, and potential ulceration. Many women exposed to irritants like dishwashing liquids or soaps while doing housework often experience cracked skin, redness, peeling, and hand dermatitis.
In the case of allergic contact dermatitis, symptoms may not appear immediately.
Symptoms can appear as early as 48-72 hours after exposure. Allergic contact dermatitis occurs in individuals who have previously been exposed to allergens, which may have happened weeks, months, or even years prior. Initially, patients may experience itching, followed by redness and swelling. On the red skin, small vesicles may appear, resembling pinheads. If the vesicles burst, they can ooze, become infected with bacteria, and form pustules. Symptoms may improve during vacations or weekends, often due to occupational exposure, while recurrences on weekends may be related to habits or environmental allergens.