When your child is having symptoms that may indicate an allergic disease, your physician can choose to run a blood test. There are different types of allergic reactions. One of the most common types is the so-called direct allergic reaction or sudden allergic reaction. This type of allergy includes allergies to grass and tree pollen (hay fever) and food allergy. The blood test is a quick way to determine if it is this type of allergic reaction your child is suffering from.
There are several blood tests available that the doctor can request, this can be different for each patient. The tests measure the amount of antibodies to certain allergens in the blood of your child. A blood test in itself is not enough proof to state if your child is suffering from an allergic disease. The medical history combined with the results of the blood test are needed for a definite diagnosis.
Prior to obtaining blood
To perform a blood test you will receive an application form following to consultation with the doctor. Did your physician decide to run a blood test prior to the first appointment, you can pick up the application form at the outpatient clinic. The assistant will inform you by telephone.
During obtaining blood
Your son or daughter will probably be less anxious if you tell him/her what’s going to happen. This is what your child can expect:
- The employee tells you where blood will be obtained, usually from the arm or on the hand of your child
- Sometimes, the skin of your child is numbed in advance by the employee by using an analgesic ointment or spray
- The skin where the blood will be obtained is cleaned in advance with a disinfectant gauze
- If blood is obtained from the arm, an elastic band (tourniquet) will be placed around the upper arm. This allows the vein to be found easier
- A needle will be pricked into a vein
- Depending on the examination one or more tubes will be filled with blood
After obtaining blood
The attending physician who requested the examination, will inform you about the outcome of the blood test. It depends on the type of blood test when the results will be available. This can range from about 2 to 6 weeks.
In addition to the blood test it could be that other examinations are needed. Additional examinations may include a skin prick test, a lung function test or a food challenge test. In many cases it will be a combination of different examinations which, together with the medical history adds up to a definite diagnosis.