So, what have we got with these new guidelines?
- We've got a lot of defined terms now. From food allergy to food intolerances to tolerance to oral allergy, we can all speak the same language by referencing the definitions included in this paper.
- It seems that we mostly rely on self-reporting as a means to track the prevalence of food allergy. That can impact the statistics as people are generally unsure of what a food allergy is and what the symptoms of a reaction are.
- It also appears that our current testing methods (blood and skin tests) are not very accurate and cause an over-diagnosis of food allergy. Oral challenges are our best means of diagnosis at the present time, but present the highest risk to patients. I would also argue based on our experience, that oral challenges become less helpful to a person who has anxiety about eating a food they're been told to avoid for many years. The challenge becomes very subjective when the person complains of vague symptoms, like "I think my tongue feels itchy" or "my throat feels funny".
- While annual food allergy testing was the standard practice, there is no evidence to support this time interval. It is unclear what time interval should be recommended.
- The guidelines suggest that doctors and professional organizations may be too conservative when it comes to their recommendations for egg allergic individuals to avoid certain vaccines such as influenza, rabies and yellow fever. Those allergic to egg may be able to tolerate these vaccines- according to some studies.
- Maternal diet during pregnancy and breastfeeding should not be restricted. Introduction of solid foods to infants should also not be delayed.
- Clear definitions for anaphylaxis are available in the guidelines with epinephrine listed as the first line of treatment, followed by evaluation in a hospital setting. Hospitals are advised to observe patients for 4-6 hours, longer if there are other complicating factors, even though we don't really have a feel for the true incidence of these bi-phasic or delayed reactions.
A patient friendly copy of the guidelines will be available in 2011, but in the meantime, if you want to slog through the lengthy document, I'll send you to the correct page in the December 2010 issue of The Journal of Allergy and Clinical Immunology.
I'd love to hear your thoughts!