Neonatal Jaundice
Neonatal Jaundice
INTRODUCTION:.Neonatal jaundicealso ashyperbilirubinemia,withinlweekofage,incident of visiblyjaundice: 60% in full-term infants, 80% inpreterm infants
• Neonatal jaundice also a s hyperbilirubinemia, • Within 1 w e e k of a g e， incident of visibly j a u n d i c e：6 0 % in fullt e r m infants，80% in preterm infants. INTRODUCTION：
Significance of Jaundice in newborn·Physiological phenomenon Pathologic signIt may be a sign of another disorder ,e.g. infectionUnconjugated bilirubin can be deposited in the brainparticularly in the basal ganglia, causing kernicterus.May develop into liver cirrhosis if biliary atresia notperform hepatoportoenterostomy in time
Significance of Jaundice in newborn: • Physiological phenomenon • Pathologic sign □ It may be a sign of another disorder ,e.g. infection □Unconjugated bilirubin can be deposited in the brain, particularly in the basal ganglia, causing kernicterus. □May develop into liver cirrhosis if biliary atresia not perform hepatoportoenterostomy in time
BreakdownofUnconjugated bilirubinhaemoglobinboundtoalbuminUnconjugatedandotherhaem proteinsGindirecubilirubialbuminConjugadionUnconjugated(gltuicurony)SHOPtransferasebilirubinLiverMETABOLICConjugatedcellsbilirubinPATHWAY OFBILIRUBINproteinZproteinSoluble in lipidsSoluble in waterExcretion聘inbileconjugatedUnconjugatedbilirubinbilirubin葡羞GlucuronyltransferaseurobilinogenEnterohepaticStercobilinogencirculationGlucuronic acid residues
ur obilinogen albumin Unconjugated (indirect) bilirubin Y protein Z protein Liver cells Unconjugated bilirubin Glucuronyl transferase Glucuronic acid residues Unconjugated bilirubin conjugated bilirubin Soluble in lipids Soluble in water METABOLIC PATHWAY OF BILIRUBIN
新生儿胆红素代谢特点(1)胆红素生成较多：（肝细胞胆红素负荷增加）：新生儿胆红素产生6-8mg/kg.d，而成人只3-4mg/kg.d1．红细胞破坏过多2.红细胞寿命短3.胆红素旁路来源较多血红素蛋白（过氧化氢酶、细胞色素P45o等）胆红素前体一无效造血4.产生胆红素的酶一血红素加氧酶含量高（1-7天）
□ 胆红素生成较多：（肝细胞胆红素负荷增加）：新生儿胆 红素产生6-8mg/kg.d，而成人只3-4mg/kg.d 1. 红细胞破坏过多 2. 红细胞寿命短 3. 胆红素旁路来源较多 ① 血红素蛋白（过氧化氢酶、细胞色素P450等） ② 胆红素前体←无效造血 4. 产生胆红素的酶—血红素加氧酶含量高（1-7天） 新生儿胆红素代谢特点(1) :
新生儿胆红素代谢特点(2)：口胆红素运输不足：血浆白蛋白量不足，或连接能力差口肝功能不成熟：1.摄取l：Y.Z蛋白1（5-15天达成人水平）2.处理I：葡萄糖醛酸基转移酶I（1周左右始↑，2周达成人水平）3.排泄1：易行成胆汁郁积口肠肝循环特殊：1.正常菌群，肠道内胆红素-一胆素原（尿胆原，粪胆原）2.β-葡萄糖醛酸苷酶个：肠肝循环个
□ 胆红素运输不足：血浆白蛋白量不足，或连接能力差 □ 肝功能不成熟： 1.摄取↓：Y . Z蛋白↓（5 -15天达成人水平） 2. 处理↓：葡萄糖醛酸基转移酶↓（1周左右始↑，2周达 成人水平） 3.排泄↓：易行成胆汁郁积 □ 肠肝循环特殊： 1. 正常菌群↓，肠道内胆红素- →胆素原（尿胆原，粪 胆原） 2. β-葡萄糖醛酸苷酶↑：肠肝循环↑ 新生儿胆红素代谢特点(2) :
Summary of neonatal bilirubinmetabolism Bilirubin loadAlbumin not enough: DefectivetransportImmaturityofliverenzymest reabsorption of bilirubin from gut胆红素白蛋白联肠肝循肝细胞处理结的胆红生成↑环个胆红素1素INeonatal infants are easy to happen jaundiceandbecome pathologic jaundice
S u m m a r y of neonatal bilirubin m e t a b o l i s m • ↑Bilirubin load • A l b u m i n not enough: Defective transport • Immaturity of liver e n z y m e s • ↑reabsorption of bilirubin f r o m gut Neonatal infants are easy to happen jaundice and become pathologic jaundice. 胆红素 生成↑ 白 蛋 白 联 结 的 胆 红 素↓ 肝细胞处理 胆红素↓ 肠肝循 环↑
Diagnostic CriteriaPhysiologic Jaundice:Pathologic Jaundice:(alloffollowsfeature)(anyoffollowsfeature)jaundice appears in 2-3d of lifejaundice appears in2w,>4w in prematureTotal serum bilirubin (TB)≤TB >12.9mg/dl (221 μmol/L)12.9mg/dl(221μumol/L)Normal conditionofBBFaded jaundice appears againDirect bilirubin(DB)>2.9mg/dl (50μmol/L)orDB/TB >25%早产儿黄疽问题？
Physiologic Jaundice: (all of follows feature) Pathologic Jaundice： (any of follows feature) jaundice appears in 2-3d of life jaundice appears in 2w, >4w in premature Total serum bilirubin (TB) ≤ 12.9mg/dl (221 µmol/L) TB >12.9mg/dl (221 µmol/L) Normal condition of BB Faded jaundice appears again Direct bilirubin(DB) >2.9mg/dl (50 µmol/L) or DB/TB >25% Diagnostic Criteria 早产儿黄疸问题？
口病理性黄疽的分类：新生儿肝炎感染性新生儿败血症新生儿溶血症胆道闭锁非感染性母乳性黄遗传性疾病
□ 病理性黄疸的分类： 感染性 非感染性 新生儿肝炎 新生儿败血症 新生儿溶血症 胆道闭锁 母乳性黄疸 遗传性疾病
Clinical Classification of Pathologic Jaundicel. InfectionJaundice:-Neonatal hepatitis :Major pathogenisvirus:CMV, hepatitisB--Neonatal sepsismechanism of jaundice happening:toxic-hepatitis,or/and hemolysis
1. Infection Jaundice： - Neonatal hepatitis ： Major pathogen is virus：CMV, hepatitis B - Neonatal sepsis: mechanism of jaundice happening: toxic-hepatitis， or/and hemolysis Clinical Classification of Pathologic J a u n d i c e