Differencial Diagnosis of Jaundice Zhang shunji Department of Gastroenterology, Zhongshan Flospiiil
Differencial Diagnosis of Jaundice Zhang shuncai Department of Gastroenterology, Zhongshan Hospital
Summarization Definition: serum total bilirubin(STB)> 34umol/L, causing a yellow color of skin sclera and tissue fluid Latent icterus: an increase of stB but not more than 34umoI/L, without color changes of skin and sclera False jaundice: yellow skin and sclera but without hyperbilirubinemia, due to ingestion of some drugs and foods
Summarization • Definition: serum total bilirubin (STB) > 34µmol/L, causing a yellow color of skin, sclera and tissue fluid • Latent icterus: an increase of STB but not more than 34µmol/L, without color changes of skin and sclera • False jaundice: yellow skin and sclera but without hyperbilirubinemia, due to ingestion of some drugs and foods
Metabolism of bilirubin Source of bilirubin Transport of bilirubin absorbed by hepatocytes Conjugation of bilirubin Excretion of bilirubin
Metabolism of Bilirubin • Source of bilirubin • Transport of bilirubin • Absorbed by hepatocytes • Conjugation of bilirubin • Excretion of bilirubin
Source of bilirubin Senile red blood cell(rBC) 80-85% RBCS lifetime: about 120 days Immature rBc 10-15% Others 1-5%. like free heme in liver and some proteins containing heme
Source of Bilirubin • Senile red blood cell (RBC) 80~85 % RBC’s lifetime: about 120 days • Immature RBC 10~15% • Others 1~5%, like free heme in liver and some proteins containing heme
Transport of Bilirubin Characteristic of free bilirubin x Unconjugated with glucuronate transferase x Undissolvable x Poisonous to biotic membrane which contains phospholid Transport formation Conjugated with albumin forming albumin-bilirubin complex, and transport to hepatocyte
Transport of Bilirubin • Characteristic of free bilirubin: Unconjugated with glucuronate transferase Undissolvable Poisonous to biotic membrane which contains phospholid • Transport formation: Conjugated with albumin forming albumin-bilirubin complex, and transport to hepatocyte
Absorption of Bilirubin 1. Intake of unconjugated bilirubin by 2. Separation of albumin from bilirubin 3. Bilirubin enters the hepatic cell 4. To the microsome by Y, Z protein
Absorption of Bilirubin 1. Intake of unconjugated bilirubin by ? 2. Separation of albumin from bilirubin. 3. Bilirubin enters the hepatic cell. 4. To the microsome by Y,Z protein
Conjugation of Bilirubin Conjugated with glucuronate 75%0, by glucuronide transferase Others 25%, conjugated with glucose, glycine Characteristic of conjugated bilirubin x Dissolvable x Nonpoisonous to biomembrane which contains phospholipid x Elimination through urine
Conjugation of Bilirubin • Conjugated with glucuronate 75%, by glucuronide transferase • Others 25%, conjugated with glucose, glycine • Characteristic of conjugated bilirubin Dissolvable Nonpoisonous to biomembrane which contains phospholipid Elimination through urine
Excretion of Bilirubin CB→ Golgi— bile capillary bile tubule→→ bile duct→ intestine→ Urobilinogen-+fecalbilinogen-+excretion lower ileum, colon-+ reabsorption portal vein+liver-bilirubin-+biles-intestine
Excretion of Bilirubin CB Golgi bile capillary bile tubule bile duct intestine Urobilinogen fecalbilinogen excretion lower ileum,colon reabsorption portal vein liver bilirubin biles intestine
Classification of Bilirubin (1) By etiology: Hemolytic jaundice Hepatic jaundice Obstructive jaundice Congenital jaundice
Classification of Bilirubin (1) • By etiology: Hemolytic jaundice Hepatic jaundice Obstructive jaundice Congenital jaundice
Classification of Bilirubin(2) By the type of bilirubin Hyperbilirubinemia mainly by unconjugated rubin Over-produced bilirubin: hemolytic jaundice Bilirubin absorption blocked: Gilbert syndrome Bilirubin conjugation blocked: Gilbert syndrome Hyperbilirubinemia mainly by conjugated bilirubin Post-hepatic obstruction cholelithiasis, cancer of the head of the pancreas Intra-hepatic obstruction; hepatolithiasis Intra-hepatic cholestasis: hepatitis, drugs, infection
Classification of Bilirubin (2) By the type of bilirubin • Hyperbilirubinemia mainly by unconjugated bilirubin Over-produced bilirubin: hemolytic jaundice Bilirubin absorption blocked: Gilbert syndrome Bilirubin conjugation blocked: Gilbert syndrome • Hyperbilirubinemia mainly by conjugated bilirubin Post-hepatic obstruction: cholelithiasis, cancer of the head of the pancreas Intra-hepatic obstruction: hepatolithiasis Intra-hepatic chlolestasis: hepatitis, drugs,infection
