HEPA 4 Flashcards
(16 cards)
What is jaundice?
Jaundice is a yellow or greenish-yellow discoloration of the sclera (whites of the eyes) and skin due to elevated bilirubin levels in the blood, typically noticeable above 2 mg/dL.
What are the types of jaundice?
The types of jaundice include hemolytic jaundice (pre-hepatic), hepatocellular jaundice (hepatic), and obstructive jaundice (post-hepatic).
What causes hemolytic jaundice?
Hemolytic jaundice is caused by excessive breakdown of red blood cells (hemolysis), which can occur in conditions like malaria, sickle cell anemia, or autoimmune hemolytic anemia.
What is the mechanism of hemolytic jaundice?
In hemolytic jaundice, the liver’s processing capacity is overwhelmed by a sudden influx of bilirubin from destroyed red blood cells, even though the liver itself is functioning normally.
What causes hepatocellular jaundice?
Hepatocellular jaundice is caused by damage to liver cells (hepatocytes), impairing their ability to conjugate bilirubin. Common causes include viral hepatitis, alcoholic liver disease, drug-induced liver injury, and cirrhosis.
What is the mechanism of hepatocellular jaundice?
The damaged liver struggles to keep up with bilirubin conjugation, leading to an accumulation of unconjugated bilirubin in the blood.
caused by a blockage in the bile duct system, preventing the flow of conjugated bilirubin from the liver to the intestines for excretion
Common causes: gallstones, tumors, and strictures
obstructive jaundice
What is the mechanism of obstructive jaundice?
In obstructive jaundice, conjugated bilirubin backs up into the liver and spills into the bloodstream due to the obstruction.
genetic conditions affecting bilirubin metabolism, such as Gilbert’s syndrome and Crigler-Najjar syndrome
hereditary hyperbilirubinemia?
occurs when there’s excessive production of unconjugated bilirubin or impaired uptake and conjugation by the liver
Unconjugated hyperbilirubinemia
What causes unconjugated hyperbilirubinemia?
increased bilirubin production from hemolysis, decreased hepatic uptake due to genetic disorders, and impaired conjugation from enzyme issues.
occurs when there’s impaired excretion of conjugated bilirubin from the liver into the bile ducts
Conjugated hyperbilirubinemia
What causes conjugated hyperbilirubinemia?
Causes include intrahepatic cholestasis (e.g., drug-induced cholestasis, alcoholic liver disease) and extrahepatic cholestasis (e.g., gallstones, tumors).
transports unconjugated bilirubin from its production site to the liver for processing and excretion
The bilirubin-albumin complex
What is the role of albumin in bilirubin transport?
Albumin binds to unconjugated bilirubin, making it water-soluble, reducing its toxicity, and protecting it from degradation before reaching the liver.
What happens to bilirubin in the liver?
In the liver, unconjugated bilirubin undergoes conjugation with glucuronic acid, transforming it into conjugated bilirubin, which can be excreted into bile.
