5/2/2012
My practice is trying to downsize (or at least revise) its inhalant allergen skin testing panel. When writing immunotherapy prescriptions, I often select the minimum number of cross-reactive allergens for treatment. For example, if a patient is sensitive to multiple Northern grasses, I might just add Timothy grass to the treatment vial. Do similar relationships hold for testing? For example, if the cross-reactive allergens Yellow Dock and Sheep Sorrel are native to our area, would it be OK to simply test for Sheep Sorrel and hope that it picks up Dock-sensitive patients? I suspect cutting down on the number of cross-reactive allergens would decrease the sensitivity of our skin testing, but I am not sure if this would be significant enough to keep excess allergens on hand for treatment and testing.

Thank you for your inquiry.

Yes, antigenic cross-reactivity relationships exist for skin testing as well as for immunotherapy. Your example is well taken. Of course, there may be some diminished sensitivity to your testing by reducing cross-reacting antigens, but my guess is that it would be minimal.

Should you wish to "downsize," the strategy that you propose is reasonable.

Thank you again for your inquiry and we hope this response is helpful to you.

Sincerely,
Phil Lieberman, M.D.