IGHE and Allergy: In our case, although no diagnostic allergy test was conducted and no history of reaction after consumption of beef and pork, the patient had a long history of owning cats, indicating potential sensitization to cat proteins and a minor possibility of anaphylactic shock due to cross-reactivity. Specific IgE tests for BSA and cat serum albumin and serum tryptase level could have made a significant contribution to clarifying the pathophysiology.