INTRODUCTION
Food allergies (FA) are an emerging health care problem in developed as well as developing countries (1). This could be due to an increase in western lifestyle in these countries. On the other hand, epidemiological data on FA from most middle income countries are quite limited (2,3). Also, FA symptoms can overlap with those of malnutrition and other childhood illnesses, making proper diagnosis difficult, especially given the limited number of allergists in developing countries (1-3). These difficulties can also be reflected in FA overdiagnosis, as demonstrated by a study carried out by Mendoza D. et al (4) in Peru, in which 40.9% of patients whose parents reported some type of FA in a national reference center of allergic diseases. Cow’s milk protein allergy (CMPA) is the FA most frequently found in children under 1 year of age. Many of the studies on the prevalence of CMPA in the region correspond to diagnoses made by self-reports with a few of them taking into account the family history of atopy, clinical characteristics, relationship with food exposure, the performance of a food allergy test or conducting a double-blind placebo control food challenge (DBPCFC) (5). This study aims to describe patients under 1 year of age diagnosed with CMPA from its clinical approach, undergoing laboratory tests, oral challenges and the acquisition of tolerance 1 year after diagnosis.