METHODS: A case report with extensive literature review.
RESULTS: 3 patients (2 females, 1 male; ages 35-58) presented to the allergy outpatient clinic after having an anaphylactic event to cow’s milk cheese. Patient 1 had two episodes of immediate urticarial angioedema and shortness of breath after ingesting Blue cheese that dissipated over 5 hours with no treatment. Skin test with positive control was negative for milk but largely positive for both pasteurized and non-pasteurized Blue cheese extracts (>10mm). Patient 2 had immediate urticaria and angioedemea after ingesting Brie cheese alleviated with diphenhydramine. Skin test with positive control showed no reaction to cow milk. Patient 3 had two hours of delayed onset of urticaria, abdominal pain and shortness of breath after ingesting lactose-free Gouda cheese requiring epinephrine injection. Skin test with positive control was negative for milk but positive for a 3mm wheal to Gouda cheese rind representing sensitization. Natamycin and rennet extracts for the cheese were obtained and skin tests of these extracts were negative with positive control. All patients were given epinephrine auto-injectors to prevent future anaphylaxis.
CONCLUSIONS: These cases highlight rare allergens in cow’s milk cheese that are not present in cow’s milk. Negative skin test for natamycin and rennet suggest there may be another process in fermenting milk to cheese that contributes to the development of allergies.