Seventy-five percent of children with milk reaction will tolerate extensively heated milk, according to a report in the July 15th online issue of the Journal of Allergy and Clinical Immunology.
Children with constant milk allergy have antibodies against specific sequential epitopes, according to Dr. Anna Nowak-Wegrzyn, from Mount Sinai School of Medicine in New York, and her colleagues. Children who have outgrown their milk allergies, however, usually have milk-specific IgE antibodies directed against conformational epitopes. Because conformational epitopes can largely be destroyed through exposure to high temperatures, the researchers reasoned that children with milk allergy might tolerate milk if it were extensively heated (baked).
In the study, 100 children were given various milk challenges. First, baked muffins and waffles containing heated milk protein were given. If these were tolerated, the subject was then given unheated milk. Subjects with tolerance to heated, but not unheated, milk continued to receive heated store-bought or home-baked products containing milk for 3 months and were then reassessed.
Overall, 68 children tolerated heated milk, but not unheated milk, 23 reacted to heated milk, and 9 tolerated both heated and unheated milk, the findings show.
Compared with the other groups, the heat reactive group had larger skin prick test wheals and higher casein-specific and milk-specific IgE levels. Moreover, the symptoms seen in heated milk-reactive subjects during heated milk challenge were more severe than those observed in heated milk-tolerant subjects who reacted to unheated milk.
Relative to their baseline values, subjects who ingested heated milk for 3 months had smaller skin prick test wheals and higher casein-IgG4. By contrast, no change in other immunologic parameters, intestinal permeability, or growth were noted.
"If confirmed, [the findings] should change our approach to the diagnosis and management of milk allergy," the authors conclude. "Allowing ingestion of heated milk products will dramatically improve the quality of life for the majority of subjects with milk allergy by vastly increasing the variety of food products they are able to consume." |
