[Persistent forms of cow's milk allergy. Report of 6 cases].

Background: Cow's milk allergy is defined as reproducible adverse reaction to a food protein antigen which is immune medieted. About 80 to 90 % become clinically tolerated within the first three year of live. The aim of this study is to evaluate the clinical, immunological and evolutive characteristics of the 10 % to 20 % of persistent form of cow's milk allergy.