9/26/2012
I have a 7-year old girl who presented for evaluation for possible stinging insect allergy. By history she developed local swelling and throat pruritus after being stung by a stinging insect when she was 3 years of age. Per mom, she was evaluated by another allergist after the incident and reportedly developed throat pruritus in the middle of the testing procedure.

We performed prick and intradermal testing with five stinging insects allergens and all tests were negative. Though 6 hours after testing she developed wheal and flair reaction to yellow hornet, yellow jacket and white-faced hornet. Blood work was ordered and was negative.

Please, advice if I should repeat skin testing? if her delayed reaction indicates possible delayed reaction to the future insect sting? should the patient continue carrying an Epipen? is immunotherapy indicated in this setting (I personally, don't think so)? Thank you very much.

Thank you for your inquiry.

I am going to refer your question to Dr. David Golden, who, as you know, is an international authority in insect sting allergy, and the author of our Parameters on insect sting reactions.

As soon as we hear from Dr. Golden, we will forward his response to you.

Thank you again for your inquiry.

Sincerely,
Phil Lieberman, M.D.

We have received a response from Dr. David Golden. Thank you again for your inquiry and we hope this response is helpful to you.
 
Sincerely,
Phil Lieberman, M.D.
 
Response from Dr. David Golden:
One key issue here is the delayed "wheal and flare" reactions to skin tests. Were these seen by an allergist? Many patients develop delayed irritant reactions that are not what you and I would call a wheal and flare response. So you could repeat at least a few of the skin tests at 1.0 mcg/ml and have her return for examination if there is any delayed reaction.

A second issue is whether her sting reaction was truly systemic, and does it warrant VIT. Where on her body was she stung? How long after the sting did she develop the throat pruritus? What were the manifestations of the throat pruritus (throat clearing/raspy, grabbing at throat, cough, gag?) or was it subjective (and how does a 3 year old express this?)? Prospective studies show that reactions only become more severe in less than 3% of children with previous systemic reactions, so her chance of severe reaction is relatively low.

So If VIT is not required, then neither are skin tests, and Epi-Pens are a matter of preference by the family given the very small chance of needing one.

As far as delayed skin tests and delayed sting reactions, both are distinctly unusual and hard to explain or predict. Patients generally follow an individual pattern of reaction, so if her initial reaction was not delayed, future reactions (if any) would probably not be delayed.

David Golden, M.D.