Liver and biliary tract disorders
Synthesis of plasma proteins
Albumin, prealbumin, transferin, coagulations factors....
Detoxication reactions of endogen toxic substances
Ammonia-urea cycle, bilirubin-clearance, bilirubin-conjugation
Detoxication reactions of exogen toxic substances
Toxic substances from environment; drugs ....
Barriere function
Barriere between gut (environment) and systemic circulation
Digestive functions
Bile production;
(bile is a complex mixture of bilirubin, bile acids, cholesterol, lecithin and electrolytes)
Metabolic center for glycids, fats and proteins metabolism
It is conjugated with glucuronic acid in the liver and extreted into the bile.
Bilirubin
is metabolic product of heme catabolism.
Bilirubin mono- and di- glucuronid is more water soluble and is easy excreted .
Hyperbilirubinemia
Icterus Jaundice
prehepatic
hepatic
posthepatic
causes of hyperbilirubinemia
Prehepatic causes of hyperbilirubinemie
adults newborns
Adults
Increased production of unconjugated bilirubin Intravascular hemolysis Hemolytic anemia
Laboratory diferenciál diagnosis.
Increas of unconjugated bilirubin Urine: bilirubin neg.; urobilinogen posit. Signs of anemie
Decreas of haptoglobin i plasma
Newborns
Neonatal jaundice; icterus neonatorum; physiologic jaundice-icterus Massive destruction of erythrocytes with fetal hemoglobin Low activity of bilirubin glucuronyltransferase
Pathological icterus associated with Rh incompatibility
Hepatic causes of hyperbilirubinemia
Alcoholic liver disease
Acute and chronic alcoholic hepatitis
Viral hepatitis A, B, C
Toxins (fungi, mushrooms))
Drugs
Autoimmune diseases.
Inborn diseases
Gilbert syndrom (unconjugated hyperbil.) Crigler-Najjar syndrome (unconjugated hyperbil.) Dubin-Jonson syndrom (conjugated hyperbil.) Rotor syndrome (conjugated hyperbil.)
Posthepatic causes of hyperbilirubinemia
Cholestasis is defined as impaired bile flow from the liver to the intestine.
Intrahepatic cholestasis
Intrahepatic cholestasis of pregnacy,
drug induced cholestasis-phenothiazines, androgens
Cholestatic forms of hepatitis
Extrahepatic biliary obstruction
Mechanical obstruction to the bile flow - choledocholithiasis (gallstones) Carcinomas of the gallblader, pancreatic head, Vaters papila Liver flukes (parasits)
Inborn anatomic deformations of the biliary tract
- Biliary atresia
Tests of hepatic synthetic capacity
The liver synthesizes a number of plasma proteins.
Total plasma protein
Albumin
Prealbumin
Coagulation proteins (factors)
Albumin.
is synthesized exclusively in the liver. Causes of hypoalbuminemia
decreas production by the liver protein malnutrition
loss from the skin, kidney, gastrointestinal tract
Prealbumin
is synthesized by the liver acts as a transport protein for thyroxin and vit. A
short half-life (1-2 days) small body pool
Good and reliable indicator of hepatic synthetic capacity
Liver enzymes
enzymes indicate hepatocellular damage
ALT, AST
enzymes indicate cholestasis and obstruction
ALP, GGT