Pork Allergy Caused by Allergies to Cats

Some types of allergy to cats can result in an allergy to pork due to cross-reaction. Learn what is behind pork-cat syndrome and who is at risk.

Cat Allergy

Allergy to cats is extremely common, occurring in up to 25% of people. Cat allergy is more common than allergy to dog dander, a fact that may be related to the potency of cat hair and dander as an allergen—and because cats generally aren't bathed. The major cat allergen, Fel d 1, is found in cat saliva, in dander from sebaceous glands in the skin, in fur, and in anal sebaceous glands. Other cat allergens, including albumin (a major protein in the blood), are found in feline urine, saliva, and blood.

Pork Allergy

Meat allergy, such as to beef, pork, poultry, and lamb, is relatively uncommon. Cooking reduces the allergenic nature of some foods by breaking down the proteins responsible for allergic reactions. If the allergen is broken down by heat, then the allergic antibody (IgE) no longer recognizes the protein, and the allergic reaction does not occur. Allergic reactions to both pork meat and wild boar meat have been reported.

Pork-Cat Syndrome

Rarely, people with an allergy to cat albumin may also be allergic to pork meat. This relationship is termed the pork-cat syndrome and is caused by the similar structures of cat albumin and pork albumin. Because of this similarity, allergic antibodies towards cat albumin cross-react with pork albumin.

Symptoms

Unlike allergic reactions to galactose-alpha-1,3-galactose—a carbohydrate found in mammalian meats, which can cause delayed allergic reactions many hours after consumption of meat—allergic reactions to pork in the pork-cat syndrome occur almost immediately after pork is eaten.

Symptoms most often include urticaria/angioedema, oral allergy syndrome, gastrointestinal symptoms (such as nausea, vomiting, and diarrhea) and anaphylaxis. Fresh (undercooked) pork meat or dried and smoked pork products tend to cause more reactions, while well-cooked pork meat causes fewer reactions.

Diagnosis

The diagnosis of pork-cat syndrome is suspected in a person who has a history of significant allergic symptoms with cat exposure (such as allergic rhinitis and asthma) and has experienced symptoms of food allergy after eating pork. Allergy testing to cat and pork are positive with either skin testing and/or blood testing. However, you are not required to have notable allergy symptoms around cats in order to be daignosed with this syndrome.

Treatment

The treatment of pork-cat syndrome is the strict avoidance of any pork product. When a reaction does occur, however, symptoms would be treated similarly to how other food allergic reactions are treated.

If a person with pork-cat syndrome avoids cat exposure, it is possible that his allergic antibody levels to a cat will decrease over time, and therefore the cross-reaction to pork will also decrease. It's, therefore, possible that a person with pork-cat syndrome will "outgrow" his pork allergy if cats are avoided.

Knowing whether an allergy is outgrown will require careful follow up with a physician, and patients with known life-threatening reactions to pork should not try to eat pork again on their own unless indicated by careful medical evaluation."