Genetic disorders of surfactant deficiency and neonatal lung disease

Pulmonary surfactant is a heterogeneous combination of lipids and proteins, which prevents alveolar collapse at the end of expiration cycle by decreasing the alveolar surface tension at the air-liquid interface. At birth, the expression of surfactant is very important for normal lung function and it is strictly correlated to gestational age. The best known genetic mutations associated with the onset of respiratory distress in preterm and full-term newborns and with interstitial lung disease later in childhood are those involving the phospholipid transporter (ABCA3) or surfactant proteins C and B (SP-C and SP-B) genes. In particular, mutations in the SP-B gene induce respiratory distress in neonatal period, while alterations on gene encoding for SP-C are commonly associated with diffuse lung disease in children or in adults. Both clinical phenotypes are present, if genetic mutations interest even the phospholipid transporter ABCA3 ambiguity in the sentence. Interstitial lung disease in children (chILD) is defined as a mixed category of mainly chronic and rare respiratory disorders with increased mortality and morbidity. Although genetic alterations are mainly responsible for the onset of these diseases, however, there are also other pathogenic factors that contribute to increase the severity of clinical presentation. In this review, we analyze all clinical features of these rare pulmonary diseases in neonatal and in pediatric age.