2352. Allergen. Antibiotic. Cephalosporin (c55), IgE antibodies
Description
The proportion of allergic reactions (AR) to antibiotics in the overall structure of adverse drug reactions reaches 2.2%.
There are two main types of allergic reactions to antibiotics:
- Immediate (Type I) reactions – occur within minutes after administration of the antibiotic and are mediated by immunoglobulin E (IgE), which stimulates the release of histamines;
- Delayed (Type IV) reactions – develop several hours or days after administration and are mediated by T cells.
Cephalosporins can act as haptens – small molecules capable of inducing an immune response only when bound to a larger carrier, such as a protein. When the drug binds to a protein in the body, it forms a complex that the immune system recognizes as foreign. This leads to the production of IgE antibodies that bind to mast cells and basophils in the blood. Upon repeated exposure to the drug, these antibodies trigger the release of histamines, resulting in allergic symptoms.
To avoid an excessive reaction upon contact with the allergen, it is recommended to perform a blood test to assess IgE levels. Detection of elevated levels of specific IgE antibodies to a particular antibiotic indicates sensitization of the body. The obtained results assist in diagnosing Type I (immediate) allergy. The analysis is performed using the Dr. Fooke method (ELISA).
When and who needs the test?
People with a predisposition to allergies, as well as those who have previously experienced allergic reactions to medications, are recommended to undergo testing:
- before starting treatment with a cephalosporin;
- in cases where skin testing is not possible (e.g., in patients with dermographism or those taking drugs with antihistamine receptor activity), or not advisable (e.g., due to lack of access to an allergist);
- prior to vaccination with live bacterial vaccines;
- in patients with kidney or intestinal diseases.
Important Notes
The absence of IgE antibodies does not rule out the possibility of delayed-type allergic reactions to this drug. Delayed-type hypersensitivity is recommended to be assessed using patch tests or the basophil activation test.
Biological material
- Venous blood
Preparing for a blood test
In order to exclude factors that may affect the test results, we recommend to follow the preparation rules:
- an important condition for laboratory tests is to take blood on an empty stomach.
- 6-12 hours before the test, you should avoid eating, drinking alcohol, smoking, and limit physical activity. Drinking...