Various digestive manifestations are common in infants less than 6 months and have a significant impact on morbidity and quality of life of the family. In a prospective study on more than 2800 Italian infants followed by 0-6 months of life, it was determined that 55% of these children had gastrointestinal symptoms such as regurgitation (23%), colics (20%), constipation (17%) or poor weight gain (15%). However, these symptoms are not very accurate, and their cause is often difficult to determine. Frequently, the pediatrician will exclude cow's milk protein in infant feeding, but without a clear etiological diagnosis was asked. This measure causes significant additional costs through the use of extensively hydrolyzed milk specifically for children and involves an elimination diet of all foods containing cow's milk sometimes for several years. This can negatively influence the growth of the child.

If the involvement of milk in these pathologies is suggested by some early studies (35% for colics, 68% in constipation, 42% in gastroesophageal reflux), it is unclear in the current state of knowledge if these gastrointestinal symptoms are actually due to an "allergy" to milk. Moreover, there is no validated diagnostic test for non-IgE-mediated gut allergy. However, various tests have proven their effectiveness in the investigation of non IgE-mediated allergy (eg. LAT, patch tests) and will be used in this study.

Inclusion Criteria:

• Infants 0-6 month old with at least one of the following symptoms : constipation, gastroesophageal reflux, colics

Exclusion Criteria:

• Prematurity
• exclusive breastfeeding
• Other cause for symptoms