- serum cow milk-IgE greater than 35 kUA/L because most (although not all) of the children with levels higher than 35 kUA/L reacted to baked milk and they tended to have more severe reactions during the baked milk challenge.
- children who had life-threatening anaphylaxis to milk within past 2 years.
- history of a convincing allergic reaction to small amount of baked milk in the past 6 months. "Allergic reaction" includes immediate symptoms within minutes to 1 hour of ingesting the food such as hives, angioedema, rhinorrhea, wheezing, cough, SOB, emesis, diarrhea).
One has to be even more careful with the outpatient challenge and choose a more conservative cut-off level, e.g. cow's milk IgE less than 5 kUA/L or cow's milk (CM) skin prick test wheal less than 9 mm.
Oral Food Challenges (click to enlarge the diagram).
How to perform the challenge with baked milk?
Here is a sample protocol for challenge with baked milk from Mount Sinai Research Center, published in JACI, 2008: Heated milk challenges were performed openly. Each muffin and waffle contained 1.3 g milk protein (nonfat dry milk powder; Nestle Carnation, Glendale, Calif).
The muffin was baked at 350°F for 30 minutes in an oven, and the waffle (less than 0.625 inches thick to ensure thorough heating) was cooked in a waffle maker at approximately 500°F for 3 minutes.
Each food was administered in 4 equal portions over 1 hour. The muffin was served first; if no symptoms were observed, 2 hours later, the waffle was served.
Patients were monitored throughout and for 2 to 4 hours after the completion of the final challenge. Challenges were discontinued at the first objective sign of reaction, and treatment was initiated immediately (source: The Journal of Allergy and Clinical Immunology, Volume 122, Issue 2, Pages 342-347.e2, August 2008).
Baked Milk Challenges. AAAAI Ask the Expert, 2011.
Challenge to baked milk - casein IgE <0.7 kUA/L is a favorable prognostic factor for tolerance of baked milk http://goo.gl/OAiiY
Food Challenges for Diagnosis of Food Allergy
Rare, medium, or well done? Effect of heating on food protein allergenicity http://goo.gl/Z4LbX - It definitely affects milk and egg products.
Milk allergy resolution calculator from CoFAR http://bit.ly/U6TkNS - Mobile version: http://bit.ly/U6TmFn
Image source: Cookie, openclipart.org, public domain.