Next+ Food Reactivity test is useful for identifying a suitable composition for an elimination diet. Currently, the definitive diagnosis of a food allergy is only possible through a food elimination trial, followed by a food challenge test. Although they are not diagnostic, combined assays of food-specific IgE and IgG are useful for identifying components for an elimination diet, when attempting to diagnose and manage a suspected adverse food reaction.
Next+ Food Test – for both IgE and IgG
Testing IgE alone gives only half-reliable results. Evidence shows there are significant improvements when choosing an elimination diet that is based on combined results for IgE and IgG, compared with IgE alone. Generally, serum testing for food-specific IgE and IgG shows an average accuracy of 75%. High negative predictive values (Ø 75% IgE and Ø 84% IgG) allow for more accurate interpretation compared with positive predictability values (15–100% IgE and 35% IgG).
The Next+ Food Test provides results for food-specific IgE and IgG relating to 23 different allergens, as well as clear advice on potential suitable ingredients and commercial diets for carrying out a food elimination trial.
The allergens tested are from meats (beef, chicken, lamb, pork, turkey, venison, rabbit, duck, horse, white fish and blue (oily) fish), milk, egg and yeast, and plant-based foods (soyabean, corn, potato, sugar beet, carrot, pea, wheat and oat).
1. Is Next+ Food Reactivity Test a diagnostic test?
No. The definitive diagnosis of a food allergy is only possible through a food elimination trial, followed by a food challenge test. Next+ Food Reactivity Test is a useful for identifying suitable components of an elimination diet, when attempting to diagnose and manage a food allergy.
2. Why are both IgE and IgG tested?
Testing IgE alone gives only half-reliable results. The evidence shows there are significant improvements when choosing an elimination diet that is based on a combination of IgE and IgG results, compared with IgE alone.
3. How long should a food elimination trial take?
The recommended length of a food elimination trial is 6–8 weeks.
4. Can different ingredients be cross-reactive?
There is evidence to show that some proteins in common food allergens can be cross-reactive. If beef does not seem to be a suitable ingredient for an elimination diet, then bison, venison, lamb and/or milk may also not be suitable. This also applies to chicken meat and that of other birds and/or egg.
5. What volume of serum do I need to send?
1.5 ml of serum.
6. How long does it take for results to be ready?
Results are available 2 days after arriving at our laboratory.