Origine et devenir des principales anomalies du développement pulmonaire

Fetal development of the bronchi and the lung occurs between the 4th and the 16th week of pregnancy, sharing the same origin with the esophagus. The most common early anomaly of the differentiation between digestive and respiratory tract leads to esophageal atresia, which also concerns the trachea. Other early developmental abnormalities concern the components of the chest, and have consequence for the lung. For instance, congenital diaphragmatic hernia leads to lung hypoplasia, abnormal bronchial division, and vascular disease. Most of the time, these abnormalities during the early development are part of a multiple-abnormality disease. A long term multi-disciplinary follow-up is necessary, because of their respiratory and extra-respiratory affections. Other anomalies during the late development lead to a limited malformation. They have different clinical expression: cystic adenomatoid malformation of the lung, pulmonary sequestration, bronchial atresia, lobar emphysema. These malformations have a common origin : a local abnormal motivity of the fetal bronchi. Severe malformations are symptomatic immediately after birth, and often lead to death. Others could remain a long time without symptoms. The most usual consequence is infection, which leads to surgery. Other complications are rare, as the association between cystic adenomatoid malformation and cancer.