Thank you for your inquiry.
In brief, I would, based upon the information given, do nothing at this time with the possible exception of giving your patient an automatic epinephrine injector. Specifically, I would not "preemptively desensitize him."
There is no indication for immunotherapy to bee sting unless the patient has had one or both of the following:
1. A systemic reaction to a sting.
2. Recurrent very large local reactions that are interfering with his/her quality of life.
The second reaction is a more recent possible indication, and below are the references that discuss this issue (1, 2).
However, one does not normally desensitize in either condition unless there is evidence for specific IgE to bee venom. You performed an in vitro test, but it is not the test of choice. The test of choice is skin testing which has a somewhat higher sensitivity. Therefore if your patient is having very large locals as described above which would make him a potential candidate for immunotherapy, in the absence of specific IgE on in vitro testing, you could perform the more sensitive skin test. But if testing was negative, then again you would have no clear-cut indication for immunotherapy at that time. Usually the only time immunotherapy would ever be given with a negative skin test plus a negative in vitro test is in a patient who has experienced a systemic (not local) reaction and who has a baseline elevated tryptase indicating the possibility of underlying systemic mastocytosis.
Thank you again for your inquiry and we hope this response is helpful to you.
1. Golden DBK, et al. Stinging insect hypersensitivity: a practice parameter update 2011. J Allergy Clin Immunol 2011; 127(4):852-854.
2. Golden, et al. Venom immunotherapy reduces large local reactions. J Allergy Clin Immunol 2009; 123(6):1371-75.
Phil Lieberman, M.D.