Card Set Information
What are the four functions of the liver?
What are three types of cells in the liver?
2) Kupffer cells
3) Biliary epithelium
What is the purpose of hepatocytes?
What is the purpose of biliary epithelium?
Allows for exchange of nutrients and hepatocyte product exchange
What is the purpose of Kupffer cells?
How many portal triads are around each central vein?
What does the liver metabolize?
Carbohydrates - glucose -> glycogen -> glucose
Fats - absorbed from intestines -> lipoproteins
Proteins - Albumin, fibrogen, prothrombin, etc
What does the liver store?
Vitamins A, D, B
Poisons/Drugs unable to be broken down
What is ALT?
Enzyme produced by liver
When is ALT elavated?
Hepatocellular disease and obstructive jaundice
All forms of hepatitis
chock and drug toxicity (cell death)
What is AST?
Produced by liver, muscle, and other tissues with high metabolic rates
When is AST elavated?
Significantly incresed with cirrhosis and acute hepatitis
Fatty changes, mets, injury
What causes AST elavation not associated with the liver?
What is ALP?
Enzyme in the cells lining the biliary ducts
Also present in bone, kidneys, intestines and placenta
Most sensetive indicator of obstruction
When is ALP elvated?
Diseases of bile ducts (Obstruction, Sclerosing cholangitis, Biliary cirrhosis) - Severe
Hepatocellular disease (Abscesses, Carcinoma, Cirrhosis) - Mild to Moderate
When is Conjugated/Direct Bilirubin increased?
When is Unconjugated/Indirect Bilirubin increased?
When is Total Bilirubin increased?
Cholestasis secondary to drugs
What is LDH?
Produced in liver, skeletal muscle, kidneys, etc
Primarily used to detect pulmonary and myocardial infarctions
When is LDH elavated?
May increase with chronic hepatocellular disease or obstructive jaundice
Moderate increase with Mono
Mainly used to detect myocardial and pulmonary infarctions
What is Albumin?
Transport protein synthesized by the liver
Helps maintain oncotic pressure
When is Albumin decreased?
Hepatocellular disease (Decreased protein synthesis)
What is PT?
Clotting factor affected by level of vitamin K
When is PT prolonged?
When is PT shortened?
What is AFP?
Produced in fetal liver
When is AFP elavated?
What should be assesed during liver scan?
What is Diffuse liver disease?
Includes fatty changes, cirrhosis, hepatitis,
Evaluated through LFTs
What is fatty infiltration?
Accumulation of lipids in hepatocytes
Results in cell injury and impaired fat metabolism
Can be reversible
What does fatty infiltration look like on u/s?
Hyperechoic (fat in cells)
Hepatomegaly over time
Increased attenuation (difficult to see posterior)
Focal Fatty Infiltration
: Hyperechoic w/hypoechoic sparing, usually in medial left lobe anterior to PH
What is Hepatitis?
Inflammation of the liver
A - fecal route
B - blood
C - non A, non B
What are characteristics of acute hepatitis?
Recovery within 4 months
Flu-like GI symptoms
Elavated AST and Total Bilirubin
Elavated ALT w/rapid decrease after several days
What are characteristics of chronic hepatitis?
Lasts > 6 months
Can progress to cirrhosis or liver failure
What is the sonographic appearance of acute hepatitis?
Increased Portal wall appearance
GB wall thickening
What is the sonographic appearance of chronic hepatitis?
Increased echogenicity (fatty changes and fibrosis)
Decreased PV echogenicity
What is cirrhosis?
Scarring - irreversible
Fibrosis, necrosis and regeneration of parenchyma (disorganized appearance)
60-70% caused by alcoholism
What are characteristics of cirrhosis?
Elavated AST, ALT, Total Bilirubin
What is the sonographic appearance of cirrhosis?
Early - hepatomegaly, fatty infiltration, increased echogenicity, increased attenuation
Late - atrophy of right lobe, caudate enlargement, echogenic coarse texture w/nodules, heterogenous
What is glycogen storage disease?
Von Gierke Disease - most common
Abnormally large amounts of glycogen deposited in liver and kidneys
Diagnosed w/blood tests
What is the u/s appearance of glycogen storage disease?
Slightly increased attenuation
Associated with adenomas and FNH
What are the characteristics of congenital liver cysts?
small - 20mm
from defect in bile ducts
anterior right lobe
What are the characteristics of polycystic liver?
associated with PCKD
multiple, simple cysts <3cm
What are the characteristics of pyogenic abcess?
variable, puss filled cysts
dirty shadowing, comet tail, microbublbles
associated with biliary obstruction and infection
What are the characteristics of candidiasis?
immunocomprimised patients (AIDS, chemo)
multiple small hypoechoic lesions
may have target/bull's eye appearance w/echoigenic center
What are the characteristics of granulomatous disease?
congenital defect in leukocytes
recurrant respiratory infections
Poorly marginated, hypoechoic
possible post enhancement or calcification w/shadowing
What are the characteristics of amebic abcesses?
asymptomatic or GI sypmtoms w/leukocytosis and fever
hypoechoic, lack of wall echoes, internal echos from debris
What are the characteristics of echinococcal (hydatid) cysts?
common in sheep-herding areas
caused by a tapeworm
"water-lily" sign / cyst within a cyst
septations, honeycomb appearance
What are characteristics of portal hypertension?
>10mmHg in portal vein
GI bleeding - vomit blood, blood in stool
What is the most common cause of portal hypertension?
What does TIPS stand for?
Portal vein thrombosis is associated with _______ ?
What are two causes for Budd-Chiari syndrome?
Congenital obstruction or thrombus in IVC or main hepatic veins
What are characteristics of Budd-Chiari?
Thrombus in IVC/HVs
hepatomegaly and splenomegaly
enlarged caudate and eventual atrophy of rt lobe
associated with HCC (invades Hepatics)
What can a arterial-portal fistula result from?
percutaneous liver biopsy or trauma
What can cause porto-hepatic venous shunts?
Congenital or related to portal hypertension
What does an intrahepatic-portosystemic shunt fistula look like on ultrasound?
complex vascular channels connecting portal vein to hepatic vein or IVC
What are characteristics of beinign tumors?
Originates from liver parenchyma or bile duct epithelial
Low vascular flow
Doesn't invade surrounding structures
What are characteristics of cavernous hemangiomas?
collection of blood vessels
solitary, "solid" mass
right lobe along periphery
Women > Men
What is the most common benign tumor of the liver?
What are characteristics of adenomas?
Associated w/birth control and glycogen storage disease
Hypoechoic mass w/possible hyperechoic center w/bleed
What is the second most common benign liver mass?
Focal nodular hyperplasia (FNH)
What are characteristics of FNH?
Composed of abnormally arranged liver parenchyma (vascular malformation)
Women <40 yrs
Well-defined, hyperechoic to isoechoic mass with depressed center
What are characteristics of malignant tumors?
invade surrounding structures
Usually from mets
What is the most common primary malignant liver tumor?
Hepatocellular carcinoma (HCC)
What is another name for HCC?
What are the 3 main types of malignancies in the liver?
Mets from colon, breast or lung
What is a predisposing factor of HCC in the US?
What are predisposing factors of HCC outside of the US?
Hepatitis B and Aflatoxin exposure
What are clinical characteristics of HCC?
History of cirrhosis or hep B or C
Possible AFP increase (70% of patients)
What are the three presentations of HCC?
1) solitary, massive tumor
2) multiple nodules throughout liver
3) diffuse infiltrative masses in liver
What is the ultrasound appearance of HCC?
hypoechoic to hyperechoic
isoechoic w/hypoechoic halo
diffuse heterogenous texture invading parenchyma
Invasion into hepatic veins/IVC
What lab values are expected with mets?
Increased AFP, ALP, and direct bilirubin
What are clinical characteristics of mets?
Increased LFTs (AFP, ALP, DB)
How does mets appear on u/s?
Anechoic to hyperechoic
Complex, target lesions
What are characteristics of lymphoma?
How does lymphoma appear on u/s?
enlarged lymph nodes around aorta (cluster of grapes)
variable appearance of lesions depending on type of lymphoma
What are characteristics of hepatoblastomas?
Most common liver malignancy in children
Heterogenous, hyperechoic or cystic w/internal septations
What are the two most common reasons for liver transplants?