Specific IgE to gelatin as a cause of anaphylaxis to zoster vaccine

[...]she had a negative assay to Fel d 2 (cat serum albumin) and pork, serological indicators of pork-cat syndrome.6 Thus, IgE results for subject number 1 eliminate both the alpha-gal syndrome and the pork-cat syndrome as the cause of her reactions to meat. Note that although alpha-gal allergy is a potential cause of anaphylaxis following zoster vaccination, only a minority of alpha-gal–allergic patients react.7 Our patient presents the enigma of a possibly tick-sensitized gelatin-allergic individual reacting to zoster vaccine while negative to alpha-gal. IgE results Four cases of alpha-gal syndrome Subject 1 Subject 2 Subject 3 Subject 4 Subject 5 Total IgE 645 1180 3021 1201 838 Alpha-gal (z5)∗