The only truly accurate testing for us have been via GI and Allergy specialists' blood tests. I highly recommend if you carry an Epipen
to also carry steroid tablets as an Epipen
only buys you 15 mins of time before it wears off. If you are Hospitalised they will give you Adrenalin, Steroids, Oxygen and hydration fluids.
We are currently doing sub lingual immunising drops which, combined with avoidance, make a difference to the IGG/IGA blood readings. It is a slow and scary path.