Skin testing with ultra-heat-treated (UHT) cow's milk in children with cow's milk allergy.

ABSTRACT

BACKGROUND: A large proportion of cow's milk (CM)-allergic children are able to tolerate extensively heated forms of CM such as baked goods. Little is known about whether ultra-heat-treated (UHT) forms of cow's milk are immunologically similar to extensively heated cow's milk and therefore may be tolerated by these children. OBJECTIVE: To determine whether skin test wheal size using UHT CM was significantly different from other forms of CM and CM extracts. METHODS: Children presenting for oral food challenges with either extensively heated or unheated cow's milk underwent skin prick test (SPT) to commercial CM, UHT CM, evaporated CM, and fresh whole CM. The results were compared between groups of children. RESULTS: At study exit, only 14% of children were avoiding all forms of CM, compared with 70% at study entry. No difference was seen in the mean SPT results for UHT CM between those children that could tolerate heated CM compared with those that could not. The mean SPT result for casein was significantly lower in those that could tolerate heated CM. However, within the group of heated milk-tolerant children, the mean SPT for UHT CM was significantly lower than the SPT for fresh whole CM. CONCLUSION: Ultra-heat-treated CM does not behave significantly differently from other forms of CM when evaluated by SPT in heated milk-allergic vs heated milk-tolerant children. This suggests that UHT CM is not sufficiently immunologically different from unheated CM to be tolerated by heated CM-tolerant children.