Factors Affecting the Severity of Neonatal Jaundice of Unknown Etiology: The Role of Enterohepatic Circulation

影響原因不明新生兒黃疸之因素：腸肝循環之角色

鄒國英(Kuo-Inn Tsou Yau) ； 陳烱霖(Chiung-Lin Chen)

《Acta Paediatrica Sinica》 33卷1期 (1992/02) Pp. 20-28

摘要

黃疸是出生一週內健康、足月嬰兒最常見的問題，且由過去的研究已知在台灣的中國嬰兒，其黃疸之發生率及嚴重度，均超過西方的嬰兒。此一前瞻性的研究乃是探討出生一週內的嬰兒，發生無明顯原因的黃疸時，影響黃疸程度的相關因素。研究對象爲136例之健康、足月嬰兒，在出生後2到5天，每天測血中膽紅素，並收集臍帶血、母親血、母乳及嬰兒糞便，以分析其中β-尿甘酸化物酵素的活性。結果顯示，出生一週內膽紅素最高值爲7或小於7 mg/dl的嬰兒，和膽紅素最高值大於7 mg/dl者相較時，其懷孕週數較高、出生體重下降得較小，且膽紅素值較早達到最高值，他們糞便中的β-尿甘酸化物酵素的活性也較低。92例嬰兒在出生後一週內曾接受母乳哺育，母乳哺育較爲成功的嬰兒（12例），有較高的比例在5天大時其膽紅素濃度仍大於10 mg/dl。母乳內β-尿甘酸化物酵素活性之高低，對母乳哺育嬰兒糞便中酵素之活性並沒有影響。臍帶血中此種酵素的活性，與母親産後血中酵素的活性呈線性相關。另由逐步多變項複迴歸統計方法的分析，顯示影響出生一星期內嬰兒血中膽紅素最高值的因素爲：懷孕週數、糞便中β-尿甘酸化物酵素活性及生産方式。因而認爲在健康、足月新生兒，出生後一週內發生的無明顯原因的黃疸時，活躍的腸壁β-尿甘酸化物酵素導致的膽紅素腸肝循環的增加，可能扮演著某種角色。

並列摘要

Jaundice is the most common condition of otherwise healthy, full-term newborns during the first week of life, and Chinese newborns are known to have a higher incidence and severity of neonatal jaundice than Caucasian newborns. This prospective study was designed to examine factors affecting the severity of neonatal jaundice of unknown etiology in the first week of life with special emphasis on the role of enterohepatic circulation. One hundred and thirty-six healthy, full-term newborns were enrolled in this study. Serum bilirubin levels were monitored daily in the morning for the first five days after delivery. Cord blood, postpartal maternal blood, breast milk and infants' stools were analyzed for β-glucuronidase activity. Infants with serum peak bilirubin level less than or equal to 7 mg/dl had older gestational age, less maximal weight loss and the bilirubin levels peaked at an earlier age than those infants with peak serum bilirubin level more than 7 mg/dl. They also had lower fecal β-glucuronidase activity in the stool collected at a mean age of 4.5 (±0.6) days. Among the 136 study cases, 92 infants received some maternal breast milk. There was considerable amount of β-glucuronidase activity in the human breast milk. Yet its presence did not affect the fecal enzyme activity. Mixed breast feeding also did not influence the serum bilirubin level in the first four days of life. However, infants fed dominantly with breast milk had a higher incidence of serum bilirubin level more than 10 mg/dl at five days old than infants fed solely by infant formula. The enzyme activities in the cord blood correlated with those in the postpartum maternal blood. By stepwise multiple regression test, factors affecting the peak serum bilirubin level significantly were found to be gestational age, fecal β-glucuronidase activity and type of delivery. We therefore conclude that enterohepatic circulation might play a role in healthy, full-term infants with neonatal jaundice of no obvious etiology in the first week of life.

並列關鍵字

neonatal jaundice ； breast feeding ； enterohepatic circulation ； β-glucuronidase