Our aim was to study the frequency and clinical correlates of two radiographic patterns of bronchopulmonary dysplasia (BPD), the cystic BPD (cBPD) and the leaky lung syndrome (LLS). Radiographic findings of BPD from sixth day of life until term in a cohort of 82 very low birth weight (VLBW) infants were evaluated and scored independently by a neonatologist and a paediatric radiologist. Data on prenatal factors and events during the first hospitalisation were collected prospectively. Forty-four (53.7%) infants showed radiographic evidence of BPD, 19 (23.2%) cBPD and 25 (30.5%) LLS. In multivariate analysis, the best predictors for radiographic BPD were oxygen dependency at 28 days (odds ratio (OR) 10.2 [95% confidence interval (CI) 2.49-41.4]), more than 2 days on ventilator (OR 10.4 [95% CI 1.8-61.5]) and volume expanders in the first 2 h (OR 7.36 [95% CI 1.32-41.2]). During the first week of life, infants with radiographic BPD received less energy per kilogram (p < 0.001) and more daily fluids per kilogram of body weight (p = 0.013). Sixty-two percent of the infants with radiographic BPD were not oxygen dependent at 36 weeks postmenstrual age (PMA). Seventeen (89.5%) of the 19 infants who needed oxygen supplementation at 36 weeks PMA also had abnormal chest X-rays.
Conclusions: Radiographic BPD findings appeared to be common in VLBW infants. In addition to the well-known respiratory risk factors (oxygen and ventilator therapy), poor nutrition and excessive fluid administration in early life seem to be significantly associated with radiological findings of lung injury in these patients.