方法：過去10年間で当院に入院し，日齢28までに死亡した症例を除外した90例（非CLD群38例，CLD群42例）を対象に診療録を後方視的に検討した。CLD群はⅢ型群と非Ⅲ型群に分け，非CLD群と比較した。
結果：非Ⅲ型群，Ⅲ型群ともに非CLD群に比べ，在胎週数が短く，人工換気日数が長かった。Ⅲ型群では出生時好中球数が高く，HFOの期間が有意に長かった。危険因子は出生時好中球数とIgMが選択された。非Ⅲ型群では摂取エネルギー量が50kcal/kg/日を超える日齢が有意に遅れ，危険因子として選択された。
結論：非Ⅲ型群では生後早期の摂取エネルギー量不足がCLDの増悪や予後を悪化する可能性がある。Ⅲ型群では子宮内感染症の影響を考慮し，娩出時期を検討する必要があるとともに，人工換気についても再考が必要と思われた。
Method：A total of 101 ELBWI were admitted to the neonatal intensive care unit of Showa University Hospital during 1996-2005. Eleven neonates who died before day 28 or born with lethal abnormalities were excluded from this study, and 90 neonates were reviewed on the medical records. Neonates who developed CLD（n＝42）were divided into CLD type Ⅲgroup（n＝12）and others（n＝30）, and compared with non CLD group.
Results：Both of CLD groups were significantly younger in gestational age and longer in periods of artificial ventilation than non-CLD group. Neutrophil counts at birth and periods of HFO in CLD typeⅢ group were significantly higher and longer than non CLD group. Neoutrophil counts was a risk factor in CLD Ⅲ group. The mean age when the total energy intake attained to 50kcal/kg/day in CLD non Ⅲ group was significantly later than non CLD group, and selected as a risk factor.
Conclusion：Early enteral feeding and paraenteral nutrition could improve the prognosis of CLD nonⅢ type. To prevent from developing CLD typeⅢ, careful management is necessary with fetuses exposed to intra-uterine infection, and a appropriate delivery mode of perinatal mechanical ventilation should be reexamined.
