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Allergic skin tests

Allergy skin tests are the most important diagnostic tool in clinics due to their reliability and ease of application in determining sensitivity to allergens.

Atopy is a concept used in the sense of susceptibility to allergies. It refers to the production of IgE against environmental allergens and hypersensitivity of the skin and mucous membranes to environmental agents. Atopy is generally familial and genetic transmission is irregular from generation to generation. Although its prevalence is 30-40% in developed countries, the incidence of overt disease is around 5-10%. Total IgE levels are increased in atopic individuals. This can cause allergic rhinitis in the respiratory system, eczema on the skin, enteritis in the gastrointestinal tract, and allergic conjunctivitis in the eye.

Skin tests are tests used to determine allergic sensitivity. Detection of allergens is important in treatments. Although the distribution of airborne allergens is determined regularly in developed countries, there are only local reports on this subject in our country. Tree pollen spreads in early spring and ends in early summer. Grass pollen is common in early summer and ends in late summer. Cereal and weed pollens spread in late summer and autumn. House dust mites and fungal spores can be found in the environment all year. Especially in humid areas, the density of house dust mites increases. Considering these conditions, allergens that should be used in the test panel should be selected.

Before the test is performed, the drugs used by the patient, which will affect the test result, should be questioned in detail. Allergens related to the complaints of the patients should be selected. In case of emergency and anaphylaxis, it should be applied by experienced personnel and the environment that can intervene in the patient.

Patch test: This test, which is used in the diagnosis of allergic contact dermatitis (allergic eczema), is applied with standard series and special patch test (dental, cosmetic, drug, clothing) series. Allergen-impregnated tapes attached to the back are removed and evaluated after 48 hours. Since late allergic reactions may occur, the test is re-evaluated at the 72nd or 96th hour. After the test strips are adhered, the patient should not take a bath and stay away from physical factors that will cause the strips to separate. With the patch test, metals such as nickel, cobalt, fragrance mix, peru balm, lanolin, colophony, paraben mix, etc., especially in cosmetic products, textiles such as formaldehyde, The materials used in the leather industry and the materials used in the tire industry are determined. Since the cause of the disease is clearly understood, its treatment and prevention methods are determined more clearly.

Photopatch test: It is applied in eczema caused by UV sensitivity of some drugs and substances in sun-exposed areas called photoallergic dermatitis. Allergens are applied symmetrically to the back and the band on one side is removed after 48 hours. Then, 5-15 J/cm2 UVA is applied and a black band is closed. After 2 days, all materials on the back are removed and an evaluation is made.

Prick test: This test is usually applied to the inner surface of the forearm (relatively hairless area) and back, by dripping allergen solutions, piercing the skin with lancets, etc. During this test, the accuracy and success of the test is evaluated by applying positive and negative controls. Prick test in people with seasonal sneezing, runny nose, tearing, Tree, grain, grass pollen, house dust mites, fungal spores, cat and dog hair, latex, coffee, red and black pepper, egg whites and yolks, fruits, walnuts, soy Allergies with foods such as cocoa, tomato, etc. are detected. It is a commonly known test among the public. Vaccination and treatments can be applied against allergen substances detected after this test.

In our country, there are many cities that experience industrialization in different sectors and impress with their greenery and nature. . We frequently see contact dermatitis in car, metal, chemicals, textile and paint, food production and storage industry workers. It is possible to reduce this frequency by preventing contact, when occupational safety mechanisms are applied in place and carefully. Eczema is also considered an occupational disease. Again, hand eczema seen on the hands of housewives can cause irritation and allergy to substances found in detergents, water, etc. even in medicines and moisturizers used.

Tree and grass pollen allergies, house mites and fungal spores that increase in a humid environment may present with allergic rhinitis, conjunctivitis and even asthma.

Allergy is a difficult picture in my opinion. The person’s own living conditions and ways of protection affect the treatment in the first degree. Since it is a condition that requires extreme awareness and patience, these tests are extremely important in terms of diagnosis. As a dermatologist, I recommend that people with these complaints have allergy tests done, as knowing the cause will be at least half of the treatment.