The Flake Study: a study trying to answer the question of whether children with fish allergy can eat flake safely.

We propose to challenge 35 children and adolescents with fish allergy with flake to ascertain the rate of flake allergy in this cohort. The intervention in this case is an oral food challenge to flake (gummy shark). Challenge will be conducted according to the ASCIA standard food challenge protocol, using incremental dosing of cooked gummy shark up to a total dose of 100 grams of gummy shark (a standard serve size; equivalent to 21 grams of protein). The gummy shark will be sourced and cooked by the patients themselves (as per standard clinical practice for food challenges) weighed prepared by the study nurses on the day of challenge. The increments (in grams of total gummy shark), which will be given every 20 min, and include: touch to the lip, 0.5g, 1.4g. 4.8g.14.3g.28.5g and rest of the fish (approximately 52g) equating to 21g of actual fish protein in total. The food challenge to gummy shark will proceed regardless of the size of the skin test to gummy shark. Cumulative and eliciting threshold doses will be recorded in grams of gummy shark ingested. A challenge will be deemed positive and stopped according to the PRACTALL criteria. PRACTALL is a European/North American co-operative of allergist and immunologists that provide consensus statements regarding best practice, including the OFC procedure, within the discipline. Our Immunology Fellow and an Allergy nurse will be performing the oral food challenges. A Consultant Allergist/Immunologist will always be present at the time of the challenge. The estimated total time commitment for the visit is between 4-6hrs. Patients who successfully passed the challenge will be asked to eat two serves (approximately 2 teaspoons of flake per serve) of flake per week for the following two weeks. It is well established that failure to re-incorporate a food post successful OFC can potentially lead to recurrence of the allergy. However, it remains unclear just how frequent the food needs to be consumed in order to maintain tolerance. Serving suggestions of 1-2 times a week are consistent with standard clinical practice in the absence of clear, empirical evidence. All patients will be contacted via phone 2 weeks following the challenge to ensure patient welfare and protocol adherence. If any post challenge reactions occur in that period or at any period following completion of the study, they will be seen at Epworth Allergy Specialists free of charge. After the initial post-challenge follow up period, participants who successfully pass the challenge will be advised to incorporate flake that they source directly, rather than purchased at a restaurant, in order to minimise the risk of inadvertent exposure particularly if allergic to another species of white fish. Participants who react to the gummy shark during the challenge will be advised to strictly avoid gummy shark. The total time period of the proposed intervention from oral food challenge to phone follow up is two weeks. We will also trial a skin prick test extract and immunoblot assay on patient serum to help refine the diagnosis of flake allergy. This involves administration of a standard skin prick test, according to the procedures outlined in the ASCIA manual for skin prick testing, using frozen, blended fresh flake extract prepared by James Cook University. Fresh food skin prick testing is commonly used in clinical practice in the diagnosis of food allergy.