RESUMO
Prevalence of cow's milk protein allergy [CMPA] is between 2 and 8%[1,2]. Results are conflicting and difficult to compare because of the different diagnostic criteria and study designs used, with prevalence rates being higher when based solely on clinical manifestations [usually parents' perception] than when using more objective diagnostic tools, such as the OFC[3,4]. The diagnosis of cow's milk protein allergy [CMPA] can be achieved with certainty only after direct observation of clinical events after milk ingestion. In fact, the common tests to identify CM sensitization [at cutaneous level or using specific IgE determination] have no absolute accuracy[5]. They can return often falsely positive in children who tolerate milk, or conversely can be negative even in the presence of a delayed, non-IgE mediated CMPA, Oral food challenge [OFC] is considered today, according to the literature, the "gold standard" for diagnosing food allergies[6,7]. Such a specific diagnosis will prevent unnecessary and potentially deleterious dietary restrictions when a suspected CMPA is not present. Unfortunately, in the world not all children can avail themselves of the OFC in milk allergy evaluation[8,9]