日本未熟児新生児学会雑誌　第27巻第1号　107 ～ 113頁（2015年）

日本未熟児新生児学会雑誌　27(1)：107-113；2015　

受付日：平成26．06．05

受理日：平成26．10．30

療育施設で早産児の核黄疸が疑われた1 例

A Case of Suspected Preterm Kernicterus which was Found at Rehabilitation Center

大阪発達総合療育センター　小児科

Department of Pediatric, Osaka developmental rehabilitation center

船戸正久

Masahisa FUNATO

Key Words：preterm infant，kernicterus，unbound bilirubin，bilirubin/albumin ratio，prolonged jaundice

　症例は，在胎32 週，出生体重1,780g の低出生体重児，Apgar score：1 分3 点，5 分6 点にて出生。生後，呼吸窮迫症候群など合併症のため21 生日まで人工呼吸管理を必要とした。その後1 歳時アテトーゼ型脳性麻痺疑いで保健センターからリハビリテーション目的のために当センターへ紹介された。1 歳時のMRI T2 強調像で淡蒼球に高信号が認められ，聴性脳幹反応（auditory brainstem response：ABR）で難聴も疑われた。そのため早産児核黄疸を疑い，出生病院から新生児管理中のビリルビン値の詳細なデータを得た。生後2 週以内の総血清ビリルビン（total bilirubin：TB）頂値は15.1mg/dL（14 生日）であった。さらに2 週以後も閉塞型の遷延性黄疸が持続し，頂値TB：18.7mg/dL（17 生日），DB（direct bilirubin）：3.2mg/dL まで上昇した。その後30 生日を越えてやっとTB が10mg/dL 未満まで低下した。元々未熟な脳を持つ早産児では，急性期だけでなくこうした遷延性黄疸にも注意を払う必要があり，学会レベルにおいても生後2 週以後の黄疸管理の多面的な研究が強く求められる。

　The case was a preterm male baby, who was born weighing 1,780g at week 32 gestational age with asphyxia（Apgar score：3 at 1 minute and 6 at 5 minutes）. After delivery he developed respiratory distress syndrome and several other complications requiring ventilator support until day 21 of life. After discharge, he was followed up at a public health center. At age 1 year, he was referred to our center for rehabilitation under a suspected diagnosis of athetotic cerebral palsy. Examination by magnetic resonance image T2-weighted image showed high intensity in the bilateral globus pallidus at age 1 year. Auditory brainstem response was abnormal with non-response to 90dB stimuli. So under suspicion of preterm kernicterus, we obtained data on jaundice from the hospital.
　According to the data, the peak value of total bilirubin（TB）within 2 weeks was as high as 15.1mg/dL（at day 14 of life）. After 2 weeks of life, prolonged jaundice also persisted up to the maximal TB value（TB max）18.7mg/dL at day 17 of life. So the prolonged obstructive jaundice continued over the 30th day of life when TB dropped down to a point less than 10mg/dL.
　The problem of preterm kernicterus has still been unsolved and has been controversial in academic meetings of neonatology. Preterm infants usually tend to have prolonged jaundice after 1-2 weeks of life. Attention should be paid not only to early jaundice, but also to prolonged jaundice in preterm infants, because they still have immature brains. Researches should be necessary on a criterion of management of jaundice especially in preterm infants after 2 weeks of life.