The recurrent and severe infections of the ENT region during childhood are frequently related to cranio-facial malformations or/and deficiency of the immune system. The cranio-facial abnormalities are at risk to be complicated by transmission deafness either primary or secondary through recurrent middle ear infections. In our pediatric out-patient clinic, most of the patients suffering severe recurrent ENT problems show variable malformations: abnormal implantation or shape of the external ear, a microretrognathism, cervical or facial branchial fistulae, high or ogival palate with anomalies of the dental occlusion or a bifid uvula. All these abnormalities share their origins in a pathological development of the first branchial arch. These developmental anomalies may directly lead to deafness (especially due to an abnormal middle car ossicular development since they are derived in part from the first arch). They may also favor secondary pathologies (middle ear otitis, abnormal soft palate). Moreover the development of the immune system is also dependent of a normal function of the endoblastic epithelium of the pharyngeal pouches which is a part of the branchial system. Immune dysfunctions may therefore accentuate the severity of the ENT Infections.