Background: Several epidemiological studies estimate that cow's milk allergy affects approximately 3-5 % of infants in industrialized countries. Infant formulae based on soy protein or hydrolysates free of cow's milk protein guarantee adequate nutritional development, although they may be inadequate for older patients.
Objective: To evaluate the possibility of using goat's milk in these patients by investigating possible cross-reactivity between both proteins in vivo and in vitro.
Methods: Twelve patients with cow's milk allergy were tested for tolerance to goat's milk protein through radioallergosorbent assay (RAST), specific IgE, skin prick and challenge tests.
Results: Only 25 % of the patients showed adequate immediate and late oral tolerance and had negative results of immunological tests for adverse reactions.
Conclusions: The use of goat's milk cannot be recommended to patients with cow's milk allergy without investigation of possible tolerance by a specialist. For the 25 % of patients that tolerate goat's protein, goat's milk can be a excellent substitute in children older than 2 years old.