Bee Sting AllergyTesting is performed using allergy skin testing or by performing a RAST. Skin testing is still the preferred method and the procedure is similar to testing for pollen or pet allergies. However, it may be necessary to use increasing concentrations of venom extracts to make a diagnosis. Allergists usually test for all stinging insects (bees, wasps, etc.) since studies have shown that people usually can't identify which type of insect stung them.
A person stung by only one insect may show positive allergy tests to more than one type of insect. In this situation, treatment using venom from all of the species is usually given.
Who Should be Tested for Venom Allergy?It's not always a clear-cut case, but in general:
Testing is not needed If a person has never been stung by an insect, or never had any symptoms (other than pain at the site of the sting) as a result of a sting, there is no need to perform any venom allergy testing.
Or, if a child under 16 years of age has only skin symptoms (such as hives and swelling) after a sting. This is because anaphylaxis will only occur in up to 10% of future insect stings.
Or, if a child or adult has a large local reaction, where swelling occurs at the site of the sting only, is not usually a reason to perform venom testing or to administer venom allergy shots. This is because the chance of developing anaphylaxis with future stings is only about 5 to 10% for both children and adults. (A few studies show that these reactions can be decrease with the use of venom immunotherapy, and this may be required in situations where stings are frequent and the swelling disrupts a person’s quality of life or ability to work.)
Testing is needed: If a person of any age has symptoms of anaphylaxis (see page 1) after being stung. That's because the person has about a 60-70% chance that future insect stings will cause a similar reaction. The chance of a reaction with a future sting will decrease over time, but still remains at about 20% many years after the last sting.
Also,if there is particular parental concern, or the child is at high risk for frequent stings, venom testing and treatment is a reasonable option. People older than 16 with these same concerns should have venom testing and treatment, given a higher risk of anaphylaxis with future stings.
Of note: If a person is found to have a positive allergy test to venom, yet has had no symptoms with stings, the chance of developing anaphylaxis with future stings is approximately 17%. As an allergist, I encounter these situations in my clinic on occasion, such as when a non-allergy physician orders a RAST test to venoms for a person who is concerned with a bee-sting allergy but without a history of a reaction. In this circumstance, because a positive test now exists, venom allergy shots need to be offered given the small (but significant) chance of a severe allergic reaction in the future.
Click page 3 for information on treatment of venom allergies.