Question 1

How accurate is environmental allergy testing compared to skin testing?

Accepted Answer

Blood-based IgE testing typically has sensitivity ranging from 60% to 95% and specificity from 30% to 95%, depending on the specific allergen being tested. There is generally good predictive value (>90%) for common environmental allergens like grass and tree pollens and dust mites. Blood testing may be preferred when skin testing isn't feasible due to skin conditions or medication use.

Question 2

Can I take antihistamines before the blood test?

Accepted Answer

Unlike skin testing, blood-based IgE testing is not typically affected by antihistamines, since it measures antibodies in the blood rather than skin reactions. However, it's always best to inform your healthcare provider about any medications you're taking, as they may have specific recommendations based on your individual situation.

Question 3

What's the difference between seasonal and perennial allergies on this test?

Accepted Answer

Seasonal allergies are typically triggered by outdoor allergens like pollen from trees, grasses, and weeds that cause symptoms during specific times of the year, while perennial allergies are often caused by indoor allergens such as dust mites, mold, and animal dander that can cause year-round symptoms. This panel tests for both types to provide a comprehensive assessment.

Question 4

Why might someone have a positive test but no symptoms?

Accepted Answer

It's possible to have a positive specific IgE result to an allergen that doesn't actually cause symptoms in the patient. The level of IgE present does not always correlate to the severity of an allergic reaction, and sensitization can occur without clinical symptoms. This is why test results should always be considered alongside symptom history and exposure patterns.

Question 5

How often should environmental allergy testing be repeated?

Accepted Answer

The frequency of retesting depends on individual circumstances and symptoms. Generally, environmental allergy panels don't need to be repeated frequently since sensitivities tend to be relatively stable over time. However, retesting might be considered if there are significant changes in symptoms, new environmental exposures, or if considering immunotherapy treatment.

Question 6

Can children have this test done?

Accepted Answer

IgE testing can be performed at any age, though reference ranges may vary slightly based on the individual's age. Environmental allergy testing in children can be particularly helpful when skin testing is difficult to perform or when trying to identify triggers for pediatric asthma or eczema.

Environmental Allergy Panel (Trees, Grasses, Molds, Dust)