Liver function evaluation
1. Detoxification & Excretory function¿¡ ±Ù°ÅÇÑ °Ë»ç
1) serum bilirubin
- van den Bergh assay : direct(=conjugated), indirect(=unconjugated)
- unconjugated bilirubinÀº albumin°ú °áÇÕÇÑ »óÅ·ΠÁ¸ÀçÇÏ¸ç ºÒ¿ë¼º(water-insoluble)À¸·Î
½ÅÀåÀ¸·Î ¹è¼³µÇÁö ¸øÇÑ´Ù.
unconjugated bilirubinÀÇ Áõ°¡´Â °£Áúȯ¿¡¼´Â µå¹É¸ç ´Üµ¶À¸·Î »ó½ÂÇÒ °æ¿ì ÀÏÂ÷Àû
À¸·Î´Â hemolytic disorder¸¦ ÀǽÉÇÏ°í ±× ¿Ü Crigler-Najjar syndrome, Gilbert syndrome
°°Àº À¯Àü¼º ÁúȯÀ» ÀǽÉÇÒ¼ö ÀÖ´Ù.
cf. Gilbert's syndrome: ÈçÇÑ ¾ç¼ºÁúȯÀÌ´Ù(3-7%).
UDP-GT(Uridine diphosphate glucuronosyl transferase) activity°¨¼Ò·Î
conjugation¿¡ Àå¾Ö°¡ »ý°Ü mild unconjugated hyperbilirubinemiaÀ¯¹ß
- conjugated bilirubinÀº ¼ö¿ë¼ºÀ¸·Î ½ÅÀåÀ¸·Î ¹èÃâµÈ´Ù.
¨ç Isolated unconjugated hyperbilirubinemia (Direct<15%)
Áï½Ã hemolysis¿¡ ´ëÇÑ work-upÀ» ½ÃÇàÇϰí
hemolysis°¡ ¾ø´Ù¸é Gilbert's syndromeÀ¸·Î »ý°¢ÇÏ°í ´õ ÀÌ»óÀÇ Á¶»ç´Â ÇÊ¿ä¾ø´Ù.
¨è Conjugated hyperbilirubinemia
Ç×»ó liver or biliary disorder¸¦ ÀǹÌÇÏ¸ç ´ëºÎºÐÀÇ °£Áúȯ¿¡¼´Â
µÑ´Ù(conjugated & unconjugated) Áõ°¡ÇÑ´Ù.
* Alb-bilirubin complexÀÇ ¹Ý°¨±â(15ÀÏ)´Â conjugated bilirubinº¸´Ù ÈξÀ ±æ´Ù.
2) urine bilirubin
urine¿¡¼ bilirubinÀÌ °ËÃâµÇ¸é ÀÌ´Â Ç×»ó conjugated bilirubinÀ̸ç bilirubinuriaÀÇ Á¸Àç´Â
°£ÁúȯÀÌ ÀÖÀ½À» ÀǹÌÇÑ´Ù.
urine dipstick test´Â 100% Á¤È®ÇÏ´Ù.
3) Blood ammonia - poor correlation
4) serum enzyme
* 3 categories
i) hepatocyte damage¸¦ ¹Ý¿µÇÏ´Â °Í
ii) cholestasis¸¦ ¹Ý¿µÇÏ´Â °Í
iii) ¾î´À°Íµµ ¾Æ´Ñ °Í
i) hepatocyte damage¸¦ ¹Ý¿µÇÏ´Â È¿¼Ò
AST/ALT : sensitive indicator
AST - liver, heart, muscle µî¿¡¼ ¹ß°ß
ALT - liver¿¡¼ ÁÖ·Î ¹ß°ß
°£¼¼Æ÷¸· ¼Õ»óÀÌ ÀÖÀ» ¶§ Åõ°ú¼ºÀÌ Áõ°¡µÇ¾î Ç÷ÁßÀ¸·Î ¸¹Àº¾çÀÌ ¹æÃâµÈ´Ù.
È¿¼Ò ¹æÃâÀ» À§ÇØ ¹Ýµå½Ã liver cell necrosisµÉ ÇÊ¿ä´Â ¾øÀ¸¸ç liver cell damageÁ¤µµ¿Í
AST/ALT ¼öÄ¡»çÀÌÀÇ »ó°ü°ü°èµµ ¾ø´Ù.
±×·¯¹Ç·Î AST/ALTÀÇ Áõ°¡°¡ acute hepatocellular disorderÀÇ ¿¹ÈÄ¿¡ Áß¿äÄ¡ ¾Ê´Ù.
ÁߵÀÇ »ó½Â(300 U/L) - ºñƯÀÌÀûÀÌ¸ç ¾îµð¼³ª º¼¼ö ÀÖ´Ù.
1000 U/L¡è - extensive hepatocellular injury¿Í °ü·Ã
i) viral hepatitis
ii) ischemic liver injury(prolonged hypotension or acute heart failure)
iii) toxin or drug-induced liver injury
´ëºÎºÐÀÇ acute hepatocellular disorder¿¡¼± ALT°¡ ASTº¸´Ù ´õ ³ô´Ù.
AST/ALT > 2ÀÏ ¶§´Â alcoholic liver disease¸¦ ÀǹÌÇÑ´Ù.
( >2 : suggestive, >3 highly suggestive )
ALT 300 ÀÌ»óÀº µå¹°¸ç ALT´Â ÈçÈ÷ Á¤»óÀÌ´Ù. ALT levelÀÌ ³·Àº ÀÌÀ¯´Â alcohol¿¡ ÀÇÇØ
pyridoxal phosphate°áÇÌÀÌ »ý±â±â ¶§¹®ÀÌ´Ù.
ii) cholestasis¸¦ ¹Ý¿µÇÏ´Â È¿¼Ò - ALP, 5-N, GGT
ALP, 5-N : bile canalicular membraneÀ̳ª ±Ùó¿¡¼ ¹ß°ß
GGT : bile duct epitheliumÀÇ endoplasmic reticulum¿¡¼ ¹ß°ß
GGTÀÇ Áõ°¡´Â ALP, 5-Nº¸´Ù ºñƯÀÌÀûÀ̸ç occult alcohol use¸¦ º¸´Âµ¥ »ç¿ëÇϱ⵵
ÇÑ´Ù.
ALP isoenzyme : liver, bone, placenta, small intestine
60¼¼ À̻󿡼 Á¤»óÀûÀ¸·Î ALP°¡ ¾à°£ »ó½ÂÇÒ¼ö ÀÖÀ¸¸ç
bone turnover°¡ ºü¸¥ û¼Ò³â¿¡¼µµ Áõ°¡µÉ¼ö ÀÖ´Ù.
Liver-derived ALP»ó½ÂÀº cholestasis¿¡ ƯÀÌÀûÀÌÁö´Â ¾ÊÀ¸¸ç, 3¹è¹Ì¸¸À϶§´Â ¸ðµç ÇüÅÂÀÇ
°£Áúȯ¿¡¼ º¼¼ö ÀÖ´Ù. 4¹è ÀÌ»ó »ó½ÂÇÒ¶§´Â
i) cholestatic liver disorder
ii) infiltrative liver disease(cancer)
iii) rapid bone turnover(Paget's disease)¿¡¼ ÁÖ·Î º¼¼ö ÀÖ´Ù.
heat-stable fraction = placenta fraction
5-N, GGT : liver diseaseÀ̿ܿ¡¼± µå¹°´Ù.
2. Biosynthetic functionÀ» ÃøÁ¤ÇÏ´Â °Ë»ç
1) serum albumin
°£¿¡¼ ÇÕ¼ºµÇ¸ç ¹Ý°¨±â´Â 15-20ÀÏÀÌ´Ù.
µû¶ó¼ acute or mild hepatic dysfunction¶§´Â ÁÁÀº indicator°¡ µÇÁö ¸øÇÑ´Ù.
3.0 g/dL ¹Ì¸¸ÀÏ ¶§´Â chronic liver disease°¡´É¼ºÀÌ Áõ°¡ÇÑ´Ù.
±×·¯³ª hypoalbuminemia´Â °£Áúȯ¿¡ ƯÀÌÀûÀÌÁö´Â ¾Ê´Ù.
: protein malnutrition, protein-losing enteropathy, N.S,
chronic infection(IL-1, TNF levelÀÌ Áõ°¡µÇ´Â)
2) serum globulin
¥ã-globulin : CLD(chronic hepatitis, liver cirrhosis)¿¡¼ Áõ°¡
LC¿¡¼ ¥ã-globulinÁõ°¡´Â AbÇÕ¼ºÀÌ Áõ°¡Çϱ⠶§¹®À̸ç, ÀÌ·¯ÇÑ Ç×üÀÇ ÀϺδ intestinal
bascteria¿¡ ÀÇÇØ »ý¼ºµÈ °ÍÀÌ´Ù. hepatic circulationÀ» ºñÄÑ Áö³ª°¡¹Ç·Î bacterial AgÀ»
Á¦°ÅÇÏÁö ¸øÇϱ⠶§¹®¿¡ Ç×ü ÇÕ¼ºÀÌ Áõ°¡ÇÑ´Ù.
IgG¡è : autoimmune hepatitis
IgM¡è : primary biliary cirrhosis
IgA¡è : alcoholic liver disease
3) coagulation factors
factor VIIIÀ» Á¦¿ÜÇϰí´Â ¸ðµÎ °£¼¼Æ÷¿¡¼ ÇÕ¼ºµÇ´Âµ¥ ¹Ý°¨±â°¡ ª¾Æ¼ hepatic synthetic
fxÀ» ÃøÁ¤ÇÏ´Â ´ÜÀÏÀÇ °¡Àå ÁÁÀº °Ë»ç¹ýÀ̸ç aucte parenchymal liver diseaaseÀÇ
¿¹Èĸ¦ Æò°¡Çϴµ¥ µµ¿òÀÌ µÈ´Ù.
* PT prolongation(5ÃÊÀÌ»ó), vit K·Î ±³Á¤X => poor Px sign
3. Liver biopsy Indication
¨ç hepatocellular disease
¨è prolonged hepatitis
¨é unexplained hepatomegaly
¨ê unexplained splenomegaly
¨ë hepatic filling defect
¨ì FUO
¨í malignant lymphoma staging