Allergy skin testing children-No needles, please!
Allergy skin testing continues to be a most valuable method to identify allergies. Even in children, the skin test may be better tolerated than attempting to obtain a blood sample.
In the above photo (circa 1996), a patient is tolerating the skin testing like a pro!
Allergy testing dates back to 1865 when Dr. Blackley abraded a quarter-inch area of his skin with a lancet, applied grass pollen on a piece of wet lint, and covered the scratched area with an occlusive bandage. This resulted in intense itching and a very large skin response in minutes.
What conditions can allergy skin testing be helpful in children?
- Allergic Rhinitis (aka “hay fever”): 20 to 40% of children have allergies!
- Asthma: 80% of children with asthma have an allergic trigger.
- Food Allergy: almost 4% of children have food allergies (not food intolerance which is very common). The disorder eosinophilic esophagitis is a complex inflammatory disorder where allergy skin (or blood testing) should be used until a better test is developed in the future.
- Eczema (atopic dermatitis): 30 to 40% of children with moderate to severe eczema have an allergic trigger such as food or environmental allergies (dust mite, pet dander).
- Hives (urticaria) & swelling (angioedema): acute symptoms (less than 6 weeks are more likely to have allergies than chronic hives (>6 weeks)
- Stinging insect allergy (bees, yellow jackets, wasps, hornets, fire ants) and penicillin reactions
When do allergies develop?
- In 80% of cases, symptoms develop before age 20
- In 40% of cases prior to age 6
- In 20% of cases prior to age 3
Why perform allergy skin testing?
- Identification to differentiate between allergic vs infectious vs irritant
- Help direct specific treatment such as:
- Implement appropriate avoidance measures (Don’t give away the cat if dust mite is the real trigger)
- Avoid unnecessary or costly medications or interventions
- Documentation that is needed if allergy shots are being considered for treatment
Where are allergy skin tests performed and how long does it take?
- The best location for applying allergy skin tests is on the back but the forearm is an alternative location
- Test results are interpreted in 20 minutes!
Allergy skin testing is NOT helpful for evaluating the following:
- Celiac disease (that is an IgA disorder requiring a blood test (TTG-IgA) and/or intestinal biopsy
- Heiner’s Syndrome: milk-induced lung disease triggered by IgG milk precipitins (blood test)
- Most medication reactions: aspirin, NSAIDs, iodine
- Reactions to: biting flies, mosquitoes, spiders, snakes, smoke, odors and fumes
Allergy skin testing should be performed cautiously in those who have:
- Previous history of severe, life threatening anaphylaxis and only by a qualified allergist
- Latex allergy (commercial latex extract is currently not available)
- Dermatographism (type of hives that occurs just from stroking the skin)
Allergy skin testing should NOT be performed:
- On pregnant women (unless there is very good indications and the benefits outweigh risks)
- By non-allergists as interpretation of skin testing results is key and performing skin tests requires skill (if applied too deep or not deep enough can result in inaccurate tests)
- While a patient is taking antihistamines or beta-blockers
- On skin that is sunburned, has a rash or on tattoos
At Family Allergy & Asthma Care of Montana, we specialize in allergy evaluations of children (and patients of all ages who are young at heart). Let us take care of you!
This information is solely for informational purposes and not intended as a substitute for consultation with a medical professional.