Atypical chronic lung disease patterns in neonates

Objective. To determine, in the postsurfactant era, the incidence and clinical characteristics of infants with atypical versus traditionally defined bronchopulmonary dysplasia (BPD) among premature infants with birth weights <1251 g. Design. Retrospective cohort study. Setting. A single regional neonatal intensive care unit Patients. Two hundred thirty-two premature infants <1251 g at birth consecutively admitted during a 2-year period. Main Outcome Measure. Incidence of classic BPD and atypical chronic lung disease (CLD) (occurring without preceding respiratory distress or after recovery from respiratory distress). Results. Among 177 infants <1251 g who survived to 28 days, 27 (15%) had atypical CLD and 61 (34.5%) had classic BPD. Atypical CLD infants were significantly heavier and more mature than classic BPD infants (mean birth weights, 922 +/- 152 g vs 854 +/- 173 g; and mean gestational age, 26.8 +/- 1.3 weeks vs 26.1 +/- 1.6 weeks). Median duration of ventilator support (31 days; range, 2 to 127 vs 42 days; range, 4-145 days) and oxygen therapy (30 days; range, 11 to 163 vs 48 days; range, 19-180 days) were shorter in atypical CLD infants than in classic BPD infants. Conclusion. Atypical CLD comprised 31% of total cases of CLD. Atypical CLD appears to be less severe than classic BPD. These data suggest that initial, acute lung injuries are not the sole antecedents of neonatal CLD.