More on food-induced anaphylaxis

Additional information for "Food allergen management", Food Safety and Hygiene July 2005.

Food Induced Anaphylaxis Reviews

Anaphylaxis is a potentially life threatening type of allergic reaction which can occur in response to any allergen including foods, vaccines, insect bites and drugs. Anaphylaxis must be treated as a medical emergency. It is a generalised allergic reaction which often involves more than one body system. The development, which may be very rapid, of cardiovascular symptoms along with airway obstruction is of greatest concern in anaphylactic reactions.

The Yunginger article noted in this Food Safety & Hygiene article (July 2005) is one of the earlier cumulative reports of fatal food anaphylaxis in the literature. In one case, where the authors concede the evidence is circumstantial, a 31 year old man who had experienced previous anaphylactic reactions to fish and other foods developed angiodema of the face and lips while dining in a restaurant. His dining partners later said that the french fries they had eaten tasted like fish.

The subject became unconscious while trying to locate and self administer his prescribed treatment. Emergency medical help was sought but resuscitation efforts at the restaurant and at a local hospital were unsuccessful. The local medical examiner attempted to obtain samples of the french fries and cooking oil but these had been discarded the day following the incident. Four of the other six cases described involved peanuts and one appeared to be a reaction to pecans in the crust of a cheesecake.

Since the Yunginger review, a number of other reports have appeared all of which suggest a growing problem.

In the US, Bock and co-workers analysed 32 fatal anaphylactic reactions to food reported between 1994 and 1999 (Journal of Allergy and Clinical Immunology 2001 107 1 1991-193). In this series peanuts and tree nuts accounted for more than 90 percent of the fatalities. Milk and fish were also implicated. Most victims were adolescents or young adults and all but one were known to have food allergy before the fatal event. All but one was known to suffer from asthma.

In another 2001 review Swiss workers have examined records in a number of European countries including the UK (Allergy 2001. 56 567 102-104). They found that of 164 fatalities from anaphylaxis recorded from 1992 to 1998, 37 (about 22 percent) could be attributed to food. Peanuts and tree nuts again led the way with seafood and milk also implicated.

A study of Singaporean hospital data examined 868 cases of anaphylactic reactions in children (less than 15 years old) between January 1992 and December 1996 (Goh et al., Allergy 1999 54 84-86). A food allergen was suspected by the attending physician in 124 cases (14 percent). No deaths were recorded and 34 percent of subjects were hospitalised for moderately severe wheezing or hypertension.

Of particular interest is the fact that the food most commonly inducing anaphylaxis was bird's nest soup. This is a Chinese delicacy made almost entirely from saliva produced by swifts to make their nests and composed mainly of glycoproteins. It is frequently consumed in this part of the world as a treatment for asthma and respiratory ailments.

In sharp contrast to data obtained from Western countries, there was a notable absence of peanuts or tree nuts as triggers for anaphylactic reactions. Egg, milk and crustacean seafood appear to be universally involved in anaphylactic reactions. Hopefully the reasons for these differences will be revealed as our understanding of food allergy increases.