[Extra-digestive manifestations of food allergy]

Intestinal manifestations are the predominant symptoms of food allergy. Nevertheless, it is generally accepted that dietary proteins can also induce intestinal manifestations such as systemic reactions or symptoms related to the skin, the respiratory tract, the central nervous system, the urinary tract, the vascular system, the joints. The cause-effect relationships between the contact with the dietary protein (e.g. it is unclear if direct skin contact is more relevant in patients with cutaneous manifestations than ingestion) and the symptoms if often difficult to prove. As a consequence, the number of "extra-intestinal" manifestations that are suggested to be related to food proteins is probably greater than the number of manifestations that are generally accepted as such.