How is an Allergy Test Performed?

The immune system protects the body from foreign and harmful substances that enter through the nose, intestines, respiratory system, and skin. In some cases, the immune system's reactions to these foreign and harmful substances may be excessive. This condition is defined as an allergy. Although the exact causes of allergies, which may have a genetic predisposition, are not fully understood, certain allergens play a significant role in the development of the disease. Allergens are grouped into five main categories: environmental allergens (house dust mites, mold spores, pollens, animal allergens), insect allergens, food allergens, drug allergens, and occupational allergens.

Types of Allergies

Allergy symptoms vary depending on the type of allergy. Generally, common symptoms include nasal congestion, post-nasal drip, cough, throat irritation, sneezing, itching, and runny nose.

Allergic Rhinitis: Also known as hay fever, allergic rhinitis can occur due to pollens, house dust, certain food items, animal fur, and chemical substances. Symptoms include runny nose, sneezing, dry cough, throat itchiness, nasal congestion, and nasal itching.
Allergic Asthma: Allergic asthma, which has a genetic predisposition, is a reaction of the lung bronchi to allergens and falls under respiratory allergies. Symptoms include chest tightness, shortness of breath, and dry cough, often caused by mold spores, cockroaches, pollen, house dust, and animal fur.
Allergic Conjunctivitis: The reaction of the conjunctiva, the membrane that surrounds the white part of the eye, to allergens is called allergic conjunctivitis. Symptoms include tearing, burning, and itching of the eyes.
Urticaria: Characterized by symptoms like itching and redness, urticaria can be caused by drug allergies, as well as allergens such as eggs, tomatoes, nuts, cow's milk, food additives, house dust, pollen, and insect bites. Food allergies, which are reactions to proteins in food, can result in symptoms such as diarrhea, stomach pain, itching, and rashes.
Atopic Dermatitis: A type of eczema seen in children between the ages of 6 months and 2 years, atopic dermatitis can progress to allergic rhinitis and asthma if left untreated.
Anaphylaxis: Swelling and pain at the site of a bee sting are known as bee allergies. This allergy can cause difficulty breathing and loss of consciousness. Anaphylaxis, a dangerous type of allergy, can be fatal.

Allergy Tests

Allergens that cause allergies are identified through blood tests or skin tests.

Prick Test: This allergy test applied to the skin can detect 20 to 30 different allergens. The skin of the patient with an allergy problem is scratched. Allergen solutions are dropped onto the scratched skin. After approximately 30 minutes, any substance that causes redness is considered an allergen.
Patch Test: This test is used to identify allergic substances that cause eczema. Chemical substances are applied to a patch, which is then adhered to the patient's back and left for 2 days. The areas with redness help identify the allergenic substance.
Blood Test: The most effective type of allergy test, the blood test measures the level of IgE antibodies in the blood. In allergic patients, this level is approximately 10 times higher than in normal individuals.

Last Updated Date: 27 March 2018

Publication Date: 27 March 2018