Unilateral Pulmonary Agenesis, Aplasia and Dysplasia

Unilateral pulmonary anomalies are rare events of unknown etiology and large clinical variability. Neonatal history does not allow for a reliable prognosis. Interdisciplinary mangament includes prenatal diagnostics and obstetrics, genetics, neonatology, pediatric cardiology and surgery as well as pediatric orthopedics. Neonatal history and long-term follow-up in three patients are presented here including a discussion of prenatal diagnostics and the embryo-genetic basics of lung development. In three term neonates the diagnoses of unilateral pulmonary agenesis, aplasia and dysplasia, respectively, were based on angiography, MRI and bronchoscopy. Neonatal presentation and long-term consequences were studied in the context of the current literature. Neonatal complications ranged from mild repiratory distress to pulmonary failure requiring mechanical ventilation. One patient developed scoliosis on long-term follow-up. Cardiac failure or pulmonary hypertension did not occur during follow-up, in one case lung malformation was accompanied by VACTER-association. Unilateral lung malformation is frequently associated with other, singular or complex anomalies (e.g., renal and vascular). A possible relationship to disrupted regulation of embryo-genetic factors such as T-BOX genes, PITX2 and growth factors ( FGF10), which regulate ASYMMETRICAL pulmonary morphogenesis is discussed. Disruptive unilateral pulmonary malformations may serve as a model for embryological lung development and other anomalies (e.g., congenital diaphragmatic hernia, unilateral hypoplasia and CCAM). Prenatal diagnosis is characterized by unilateral hyperechogenicity of the affected lung. Neonatal presentation is determined by mediastinal shift which may be corrected by tissue-expander implantation. Associated anomalies require cytogenetic analysis and sequencing of currently known mutations. Long-term follow-up by echocardiography and pulmonary function testing is mandatory in these patients.