Thank you for your inquiry.
Unfortunately, there is no either in vivo or in vitro mechanism by which you can assess whether or not your patient can take influenza vaccine other than an actual challenge. Therefore, the decision becomes one of risk/benefit analysis, and there is no definitive answer.
In my opinion, the reaction you described would be very unusual after the administration of influenza vaccine, and I believe it is more plausible that there was another cause. Since influenza vaccine is desirable in her case, again, in my opinion, the benefit of a challenge outweighs the potential risk. However, I would do a graded challenge, and suggest the following format:
Administer 0.01 cc of the vaccine, and observe for 24 hours. If there is no reaction, administer 0.1 cc of the vaccine and observe for another 24 hours. Again, if there is no reaction, administer 0.2 cc, and observe for another 48 hours. If there is no reaction after the 0.2 cc dose, give the remainder of the therapeutic dose (0.3 cc).
Thank you again for your inquiry and we hope this response is helpful to you.
Sincerely,
Phil Lieberman, M.D.