Epidemiology, presentation, clinical course, and radiological and pathological findings of bronchopulmonary dysplasia (BPD) have recently changed with the effects of technological progression in the field of neonatology, and this change has also affected the nomenclature and definition of BPD. In this article new insights about the changing definition, pathogenesis, epidemiology and pathology of BPD have been reviewed. There are several risk factors for BPD, of which some are preventable. Immaturity, baro/volutrauma, oxidative stress, infection/inflammation and proteolytic tissue injury mechanisms that might have intrauterine onset and some antenatal factors are considered highly responsible and are under intense investigation. Seemingly healthy premature newborns who do not have respiratory distress syndrome (RDS) at birth may develop oxygen dependency and chronic lung disease in days in contrast to “old BPD”, which has a classical course following RDS. This “new BPD” has mild histopathological findings, including mild vascular lesions, alveolar simplification and arrest in lung development when compared with and in contrast to “old BPD”, which has fibrosis with severe parenchymal injury, and severe epithelial, smooth muscle, cellular and vascular hypertensive lesions.

Keywords: Bronkopulmoner displazi, eski BPD, yeni BPD, kronik akciğer hastalığı, prematürite, yenidoğan, Bronchopulmonary dysplasia, chronic lung disease, newborn, new BPD, old BPD, prematurity