General Features of Liver Disease Flashcards
What are the components of a portal triad?
- hepatic artery
- portal vein
- bile duct
–not hepatic vein–
What are reversible signs of liver damage?
- fat accumulation (steatosis)
- elevated bilirubin (cholestasis)
- swelling
- clumping of intermediate fillaments -> Mallory hyaline
What are signs of irreversible liver damage?
- coagulative necrosis; begining as confluent necrosis (zone 3, around central vein) -> bridging necrosis (connects central vein to portal triads) -> pan-acinar necrosis (multiple adjacent acini)
- apoptosis; eosinophilic cytoplasm, condensation (pyknosis) and fragmentation (karyorrhexis) of chromatin
How does the liver repair itself following damage?
What does this look like in chronic liver disease?
- stellate cell activation replace lost parenchma with fibrous scar tissue
- surviving hepatocytes divide to regenerate lost parenchyma
In chronic liver disease this process occurs repeatedly overtime and areas of regenerating hepatocytes will become surrounded by fibrous septae -> regenerative nodules, this is cirrhosis
What is liver failure?
How does it present?
loss of 80-90% of liver function
presentation varies with acute or chronic setting but both include:
- hepatic encephalopathy -> asterixis
- coagulation abnormalities
- N/V
- elevated bilirubin -> jaundice/icterus & itching
What are causes of liver failure?
ABCDE
- A: Acetominophen, HAV, Autoimmune
- B: HBV
- C: HCV
- D: Drugs/toxins (aflatoxin), HDV
- E: HEV, esoteric (rare; Wilson’s disease and Budd-Chiari)
- F: Fatty, microvesicular (microvesicular steatosis; pregnancy, valproate, tetracycline, Reye syndrome)
What is acute liver failure?
(appearance)
occurs within 6 months (26 weeks) of injury
caused by massive hepatic destruction
- shrunken liver
- massive necrosis w/ or w/o regeneration/scaring (depends on timing)
How does acute liver failure present?
- elevated ammonia -> hepatic encephalopathy -> asterixis
- decreased coagulation factors (elevated PR/INR) -> coagulation abnormalities
- N/V
- elevated bilirubin -> jaundice/icterus & itching
- elevated AST/ALT (hepatocyte damage)
What are the main causes of acute liver failure?
- acetominophen (50%)
- autoimmune hepatitis
- drugs/toxins (aflatoxin and aminita mushroom)
- acute HAV and HBV infections
How is acute liver failure treated?
- supportive (fluids, circulation, and respiration)
- control bleeding
- lactulose for ammonia
- prophylactic ABX
- liver transplant
- N-acetylcysteine (in acetominophen OD)
What are complications of acute liver failure?
What are the main causes of death?
Complications:
- GI bleeding
- coagulopathy
- multi-organ failure (heart, lung, and kidneys)
- coma
Cause of death:
- cerebral edema
- sepsis
What is an unusual presentation of acute liver failure?
What causes are associated with it?
acute liver failure w/o obvious cell death/necrosis
caused by widespread hepatocyte dysfunction rather than loss:
-diffuse microvesicular steatosis of fatty liver of pregnancy
-idiosyncratic drug reactions (valproate and tetracycline)
What is chronic liver failure?
(appearance)
progressive loss of liver function due to chronic liver disease
often associated with cirrhosis
How does cirrhosis/chronic liver failure present?
often masked early by prexisiting liver disease -> asymptomatic
signs of acute liver failure + portal hypertension + hyperestroginemia (men only)
Why does men with cirrhosis/chronic liver failure have hyperestrogenemia?
How does this present?
impaired metabolism of estrogen due to impaired liver function
Presentation:
- palmar erythema
- spider angiomata
- hypogonadism
- gyenicomastia
- infertility
- erectile dysfunction
What are the main causes of chronic liver failure?
- chronic HBV and HCV
- alcoholic liver disease
- non-alcoholic fatty liver disease (NAFLD)
How is cirrhoisis/chronic liver failure treated?
- treatment of underlying condition
- control of symptoms
- monitor for HCC
- liver transplant
What are complications of cirrhosis/chronic liver failure?
- HCC
- GI bleeding
- coagulopathy
- hepatorenal syndrome
-ascites
-sepsis (spontaneous bacterial peritonitis)
What are prognostic tools for cirrhosis/chronic liver disease?
MELD (model for end-stage liver disease):
- calculated using bilirubin, creatinine, and INR (CMP + INR)
- high score = worse prognosis
- score of >14 indicates transplant
Child-Turcotte-Pugh Score:
- uses bilirubin, albumin (CMP), PT/INR, and exam findings
- A (well compensated), B (partially decompensated), and C (decompensated)
What is portal hypertension?
increased resistance of blood flow in the portal vein
What are the causes of portal hypertension?
Pre-hepatic:
-thrombosis
Intrahepatic:
- cirrhosis (**most common**)
- schistosomiasis (**second most common**)
- malignancy
Post-hepatic:
- Budd-Chiari syndrome/hepatic vein obstruction
- right sided heart failure
What is the presentation of portal hypertension?
- ascites
- portosystemic shunts: esophageal varicies, caput medusae, hemorrhoids
- congestive splenomegaly
- hepatic encephalopathy
What is ascites?
Accumulation of fluid in the peritoneal cavity
Clinically detectable as a fluid wave at 500mL
What causes ascites?
- mainly caused by portal HTN secondary to cirrhosis (80%)
- non-portal HTN related: malignancy, pancreatitis, infection, hypoalbuminemia
