Unilateral disruptive lung malformation: Genetics,embryology,management and follow-up

Abstract

Unilateral pulmonary malformation presenting as agenesis, aplasia or dysplasia is rare with variable outcome. Neonatal presentation does not allow for a reliable prognosis, ranging from mild repiratory distress to severe pulmonary failure requiring mechanical ventilation. Unilateral lung malformation frequently indicates other, singular or complex defects (e.g.: renal, vascular). Disrupted regulation of factors involved in early lung morphogenesis (e.g. T-box-genes, Pitx2, FGgf 10 and cell signaling pathways such as sonic hedgehog and Wnt) may be involved in the etiology of pulmonary malformation. Suspected lung agenesis, aplasia and dysplasia on fetal ultrasound should direct perinatal management and complete diagnostic work-up. Consideration of associated anomalies frequently observed improves identification and management of these potentially vital conditions.

Presence of additional defects, predominantly vascular and/or genitourinary anomalies, contribute significantly to prognosis. Pulmonary hypertension may result from reduced lung vascular capacity. Development of thoracic deformity significantly impacts quality of life in these patients. Interdisciplinary management is required in presence of additional defects.

This article reviews the current experience on neonatal management and long-term-follow-up including discussion of prenatal diagnosis, the embryo-genetic basics of lung development and suggestions for diagnostic work-up.