A recent abstract promoted at the American Thoracic Society meeting on the topic of children with asthma being prone to peanut sensitization. The authors suggest children who do have asthma are more likely to be sensitive to peanuts and therefore kids with asthma should be tested for peanut allergy.
This abstract was received with a lot of controversy. If there is no clinical history of peanut allergy in a child that has asthma, no there is no indication to test for peanut allergy, but environmental testing may be helpful. There is no evidence in diagnosing peanut allergy helps treat asthma. Chronic asthma is not a manifestation of peanut allergy or peanut sensitization.
The diagnosis of food allergy results in symptoms of cough, wheezing, hives, swelling, vomiting etc. Without a history of this, food testing is not indicated. These reactions usually occur within 2 hours after ingesting a food, and usually it occurs much sooner. Besides peanuts, the most common food allergies are tree nuts, shellfish, fish, wheat, milk, soy and eggs.
Chronic and poorly uncontrolled asthma is not a result of a hidden food (peanut) allergy. There is no reason to do food allergy testing in these patients unless the clinical history indicates it as above. But asthmatic children who have asthma could benefit from inhalant (environmental testing). i.e. pollen, animal dander, dust mites.
Food allergy testing from a blood test or a skin test is insufficient to diagnose a food allergy. Many patients on food testing show up positive to a food and there is no clinical history after eating the food in question. Positive food testing results should always be interpreted with a clinical history. If a patient has no history of any allergic reactions after eating a certain food, then allergy testing for that food is not necessary.
While children who have food allergy have a higher risk of asthma, and children who have asthma have a higher risk of food allergies, food allergy testing every asthmatic child is not indicated. What is more worthwhile is environmental allergy testing. Many children with asthma are triggered by allergens in the environmental such as trees, grass, weeds, dust mite, molds, dogs and cats. Knowing which inhalant allergens a child is allergic to can help manage asthma.
So in conclusion if your child has asthma it is not necessary to do allergy tests for foods (especially peanut), but allergy testing for inhalant allergens is actually more beneficial. Your local allergy doctor or allergist can perform allergy testing in the office for you.