Liver Pathology I - SRS Flashcards
What enters the liver at the porta hepatis?
- Portal vein
- hepatic artery
- bile duct
Identify the structures shown.
What is the normal diameter of an anatomic liver lobule?
1-2 mm
Identify the indicated structures
What is the space of Disse?
Obstruction here can lead to what?
Space between Sinusoids and the hepatocytes.
Contains lymph and interstitial fluid.
Can lead to portal HTN
Identify the blanked out structures
Top: hepatocyte
Bottom: Bile canaliculi
Identify
Left: Lumen of the sinusoid
Right: space of disse
The endothelial layer is fenestrated and not supported by a basal lamina. What are the hepatocytes directly exposed to?
Plasma
Where are we here?
Lumen of a hepatic sinusoid with the endothelial cell coating, displaying the typical fenestrations arranged as clusters and forming the so-called sieve plates.
What cells are found in the cords and sinusoids?
Hepatocytes
sinusoidal endothelial cells
kupffer cells
stellate (ito) cells
What is the role of the stellate cell?
Storage of fat, vitamin (A in particular), fibrous tissue metabolism
What makes up the portal triad?
Portal vein
hepatic artery
bile duct (and lymphatics)
Identify
Top: Portal triad
Bottom: Central Vein
In the liver acinus, where is the highest oxygen tension?
Zone I
Identify the indicated structures.
Green = Zone I
Orange = Zone II
Red = Zone III
From the portal triad, describe the flow of blood.
Hits zone one first, highest O2 concentration here.
Goes then to zone II and then Zone III, before finally reaching the central vein to drain.
What zone has the lowest O2 concentration?
Zone III
What is the “supporting structure” for the hepatocytes?
Reticulin
List as many of the metabolic functions of the liver as you can.
- Formation and excretion of bile during bilirubin metabolism
- Regulation of carbohydrate homeostasis
- Lipid synthesis and secretion of plasma lipoproteins
- Control of cholesterol metabolism
- Formation of urea, serum albumin, clotting factors, enzymes, and numerous other proteins
- Metabolism or detoxification of drugs and other foreign substances
What are the major causes of liver injury?
- Infection
- Immune mediated
- Drug and Toxin
- Metabolic
- Genetic
- Autoimmune cholangiopathy
What are two big drug/toxin causes of liver injury?
Acetaminophen
Ethanol
What are three examples of genetic causes of liver injury?
–Hemochromatosis
–Wilson’s disease
–Alpha-1 antitrypsin deficiency
What are two examples of autimmune cholangiopathy?
–Primary biliary cirrhosis
–Primary sclerosing cholangitis
What is the definition of acute liver failure?
Evidence of coagulation abnormality and any degree of mental alteration in a patient without pre-existing cirrhosis and with an illness less than 26 weeks duration.
Acute Hepatic Failure is onset of liver failure within 26 weeks after onset of new liver disease defined by evidence of impaired liver function with increased PT and encephalopathy.
What amount of hepatocytes must be lost to manifest this way?
What is the mortality rate?
What is the treatment approach?
Caused by: >80% loss of hepatocytes
Mortality rate: 40-80%
Approach: Hospitalize and consider liver transplantation
What does fulminant hepatic failure describe?
used to describe the development of encephalopathy within 8 weeks of the onset of symptoms
What are five manifestations of acute liver failure?
- •Jaundice
- •Neurologic symptoms
- •Encephalopathy
- •Portal hypertension
- •Hepatorenal syndrome
What can the presentation of hepatic encephalopathy look like?
•can range from sleep disturbance –> lethargy –> deep somnolence –> coma
What type of neurologic symptoms can acute liver failure cause?
•symptoms can include a asterixis (flapping tremor) and hyperactive reflexes.
What is hepatorenal syndrome triggered by?
- thought to be triggered by vasodilation in the splanchnic circulation leading to decreased renal perfusion and glomerular filtration.
How do we determine the extent of hepatocyte injury in the lab?
AST, ALT
What laboratory tests do we use to identify cholestatic biliary tract dysfunction?
–Serum bilirubin (direct and indirect)
–Alkaline phosphatase
What do we use to assess the sythentic capabilities of the liver?
What are the half lives of these things?
–Serum albumin (20 day half life)
–Coagulation factors (5-48 hrs half life)
Liver failure may follow acute injury or chronic injury, but may also occur as an acute insult superimposed on an otherwise well-compensated chronic liver disease.
What is the mnemonic for causes of acute liver failure?
–A: Acetaminophen, hepatitis A, autoimmune hepatitis
–B: Hepatitis B
–C: Hepatitis C, cryptogenic
–D: Drugs/toxins, hepatitis D
–E: Hepatitis E, esoteric causes (Wilson disease, Budd-Chiari)
–F: Fatty change of the microvesicular type (fatty liver of pregnancy, valproate, tetracycline, Reye syndrome)
He said he wasn’t sure if this would be worth a shit though, so hey, whatever.
Liver failure entails what serious and potentially fatal sequelae?
Coagulopathy
encephalopathy
Portal HTN
Esophageal Varices
Hepatorenal syndrome
Portopulmonary HTN
What determines the presence of chronic hepatitis?
Persistent liver disease (AKA)
lasting for more than 26 weeks