The main allergy-related indicator in routine blood tests is the eosinophil level, but the detection of allergies also requires a combination of tests such as the allergen skin prick test.
Eosinophil levels are usually increased in routine blood tests when an allergic reaction occurs in the body.
Normal serum eosinophils (0.05 to 0.5) x 10⁹/L account for 0.5% to 5% of the total. In the event of an allergic reaction, peripheral blood eosinophils can reach more than 10%.
It should be noted, however, that elevated eosinophils are not always due to allergy. Eosinophilia can also occur in diseases such as parasitic infections, eczema, pemphigus, psoriasis and other skin diseases, as well as in hematologic diseases such as chronic myeloid leukemia and hypereosinophilic syndrome.
At the same time the detection of allergy, but also need to combine the medical history, allergen skin prick test, patch test and other test results, comprehensive analysis. Suspected allergies should be promptly to the hospital to avoid delaying the disease.