日本未熟児新生児学会雑誌　第17巻　第1号　57～67頁（2005年）

日本未熟児新生児学会雑誌　17(1)：57-67；2005　

受理日：平成16．09．09

晩期循環不全と出生後発症の脳室周囲白質軟化症（PVL）との関係

Late-onset circulatory collapse and late development of periventricular leukomalacia in infants less than 33 weeks gestational age.

＊1大阪市立総合医療センター　新生児科，＊2東京女子医科大学　母子総合医療センター

＊1Department of Neonatology, Osaka City General Hospital，＊2Department of Neonatology, Tokyo Women's Medical University Hospital

中西秀彦＊1・松波聡子＊1・郡山　健＊1・江原英治＊1・金　太章＊1・楠田　聡＊2

Hidehiko NAKANISHI＊1，Satoko MATSUNAMI＊1，Takeshi KORIYAMA＊1， Eiji EHARA＊1，Tae-Jang KIM＊1， Satoshi KUSUDA＊2

Key Words：prematurity，adrenal insufficiency，periventricular leukomalacia，chorioamnionitis

　脳室周囲白質軟化症（PVL）は未熟児のintact survivalを目指す上で最も予防に注意が必要な疾患である。一方，全身状態が安定していた早産児が生後1カ月以降急激に循環動態の悪化を来たし，ステロイドホルモン投与が必要になることがある。PVLは脳虚血性病変なので，この晩期循環不全（late-onset circulatory collapse：LCC）と出生後PVL（later PVL）との間には密接な関係があると考え，1994～2002年での当院NICUにおける在胎期間32週以下の児583例を対象としてlater PVLを呈した児を後方視的に検討した。その結果，later PVL群では出生体重，在胎期間が有意に低く，LCC，脳室内出血（IVH），壊死性腸炎（NEC）との間に有意な関係（p＜0.001）を認めた。LCCは脳虚血性変化を受けやすい時期である在胎29週頃に発症していた。またLCC 7症例中5例（71%）に絨毛膜羊膜炎を認めた。later PVLを従属変数として多変量解析を行った結果，LCC，重度IVH，NECの合併が独立してPVLの発症に関係していた。LCCの予防がlater PVLの予防につながる可能性が考えられた。

　Periventricular leukomalacia（PVL）is a main cause of cerebral palsy and without any effort to take care for the prevention, we couldn't have achieved intact survival of premature babies. We have been seeing many premature infants who suddenly showed circulatory collapse around one month after birth. In those cases, the steroid hormone replacement therapy improved all their conditions rapidly. After these episodes, some patients developed cystic-PVL. Therefore, we assume that late-onset circulatory collapse derives from the adrenal insufficiency of prematurity, and believe that there is a strong relationship between the late-onset circulatory collapse and late development of PVL（later PVL）．In this study, we evaluated the sequence of the late-onset circulatory collapse and later PVL in premature infants. From 1994 to 2002, totally 583 patients less than 33 completed weeks were enrolled in this study. Several clinical markers of the patients were retrospectively investigated. Infants with shorter gestational age and lower birth weight had a higher incidence of later PVL. There was a significant correlation between the late-onset circulatory collapse and later PVL（p＜0.001）．The period of late-onset circulatory collapse was around 29 weeks gestational age, at which cerebral white matter was generally vulnerable to ischemic changes. Among later PVL cases, frequencies of chorioamnionitis were higher in late-onset circulatory collapse cases. The results of the multivariate analyses of later PVL showed late-onset circulatory collapse, severe IVH, NEC were independently related to the later PVL. Considering that, prevention of late-onset circulatory collapse may lead to prevention of later PVL.