There are various types of laboratory tests, the ones that help determine whether a person has an allergic reaction and, if identified, what the degree of its severity is.
What are they for?
in humans – a reaction of immunity, which occurs when in contact with a substance that causes increased sensitivity. Every allergic person has an individual reaction to their allergen. Usually, when this substance enters the gastrointestinal tract or on the surface of the skin, or on the mucous membrane of the nasopharynx, bronchi or eyes, the immune system begins to increase the production of immunoglobulin E, which is the beginning of the chain that eventually leads to an inflammatory process.
They allow you to find exactly the specific substance that causes this immune response in the body. This analysis is carried out in the laboratory. To do this, blood is taken and checked for what substances it produces specific antibodies.
They are safer and more effective than skin ones. (During the last one a scratch is made on the skin and various allergens are dropped onto it. Then, the reaction is judged whether the substance is allergic to this substance or not).
It cannot determine all existing allergens, and therefore it is usually preliminary, which is carried out for the future direction of research.
If the reaction was positive, then laboratory ones will be conducted to search for specific substances. How is it done? The patient is taken for analysis of blood, distributed in different tubes containing different allergens. Then the drugs are examined with special samples, and the more antibodies are released, the more likely it is to be allergic to the substance.
Specific immunoglobulin E test
It is a blood one that is highly accurate. Blood is also taken, after which it is mixed with very specific allergens of three groups of drugs: inhalation, contact and food.
Inhalation group contains:
- plant pollen;
- house dust;
- animal hair;
- bird fluff;
- fungal spores;
- dry food (aquarium fish, etc.)
Contact allergens contain components:
- household chemicals;
- cosmetics and so on.
The food group contains various foods, the list of which may be in the hundreds of items.
When is a test prescribed?
It is prescribed if:
- the patient has obvious symptoms of allergy, which occur either seasonally, or after eating some kind of food or after contact with some substance;
- the patient underwent a long and ineffective treatment of chronic bronchitis, rhinitis, conjunctivitis, dermatitis;
- the patient has a genetic propensity for allergies;
- the patient complains of cough, shortness of breath, conjunctivitis, rhinitis, while working in hazardous production;
- there are obvious symptoms of hypersensitivity;
- to track the effectiveness of allergy treatment during its treatment.
Based on the test results, the level of immunoglobulin E in the serum is determined in three levels – the “low”, “medium” or “high” immune response.
The test results are presented in tabular form with an indication of the study, and the degree of immune response.
Why is it important?
The degree of the immune response is necessary to know both the doctor and the patient. This is what can help or completely get rid of allergies or significantly reduce the allergic reaction.
Low level of immune response: contact is not necessary to exclude, since the sensitivity to the allergen is small.
The average level of immune response: it is desirable to limit contact with a substance that is defined as a clear allergen.
High level of immune response: it is important to completely eliminate contact, even in small quantities.
How are blood tests taken?
The patient must prepare for its maximum effectiveness:
- Donation is carried out in the morning on an empty stomach.
- 2 hours before testing is prohibited to smoke.
- 5 days prior to analyzes exclude products with a high degree of allergenicity:
- chocolate or cocoa products;
- food / beverage, with synthetic sweeteners, flavors and colors;
- dairy, fermented milk products;
- citrus fruit;
- off-season vegetables and fruits.
- 5-7 days before donating, it is important not to expose yourself to heavy physical and emotional stress.
- 5 days before donation, it is necessary to exclude the possibility of contact with pets.
- To take a blood test for the identification of allergens need in remission. This is done in order to maximize the level of specific antibodies to normal (during the period of exacerbations, it rises, and the picture will be “blurred”). If this rule is observed, the immune reaction of the blood to the allergen will be more vivid and realistic.
- It is advisable during the week before the analysis to try not to take any medications, if possible, even if, as you think, they do not affect your allergies.
- It is important not to take antiallergic (antihistamine) drugs, since they reduce the level of histamines (antibodies) and will show a false result. This item should be discussed with your doctor, because in some cases, with severe allergies, the cancellation of these drugs can be dangerous for the patient.
- You should not donate blood for subsequent laboratory allergological tests, if you have a fever, acute respiratory viral infections, acute gastrointestinal diseases and other acute conditions.
If the above conditions are met, the result of immunological tests will be as accurate as possible. And the more accurate it is, the more correct the prescribed treatment will be, which will soon save the patient from allergies.