Pathology of the Liver Flashcards
Fatty Infiltration (Steatosis)
Build up of fat in >5% of liver cells
Two types – non-alcoholic and alcoholic
Non-alcoholic fatty liver disease (NAFLD)
May or may not have associated inflammation
Non-alcoholic steatohepatitis (NASH)
Associated with dyslipidaemia
Can be reversed before NASH and scarring occurs
Alcohol-related fatty liver disease (AFLD)
Preventable; can be reversed when stop drinking
ALD can lead to enlarged liver, alcoholic hepatitis, and alcoholic cirrhosis
Ultrasound Presentation:
Mild: Minimal diffuse increase in hepatic echogenicity
Moderate: Increased echogenicity with slightly impaired visualisation
Severe: Significant increase in echogenicity of the liver parenchyma & decreased penetration
Diffuse disease of the liver
- Diffuse hepatocellular disease affects the hepatocytes and interferes with liver function
- The hepatocyte is a parenchymal liver cell that performs all the functions of the liver
- Diffuse disease is measured via liver function tests (LFTs)
- The hepatic enzyme levels are elevated with cell necrosis (tissue death)
Hepatitis
Inflammation of the liver
Can be acute or chronic
Most commonly caused by viral infection
Other causes include autoimmune hepatitis, and hepatitis secondary to medications, drugs, toxins, and alcohol
S&S – acute hepatitis: Fatigue Sudden nausea and vomiting Abdo pain/discomfort, esp RUQ Low-grade fever Dark urine Joint pain
Ultrasound Presentation – acute hepatitis:
Liver texture may appear normal, or portal vein may appear more prominent than usual
Liver parenchyma is slightly more hypoechoic due to swelling of the liver cells via inflammation
Increased ‘brightness or prominence’ of the portal veins (star effect)
Attenuation may be present
Hepatosplenomegaly is present
Gallbladder wall is thickened
Chronic hepatitis:
May be asymptomatic
Can progress to fibrosis and cirrhosis (scarring) and liver failure
2 types:
Chronic persistent hepatitis – a benign, self-limiting process (heals itself)
Chronic active hepatitis – usually progresses to cirrhosis and liver failure
Ultrasound Presentation – chronic hepatitis:
Liver parenchyma is coarse and more echogenic / hyperechoic due to fibrosis
Portal vein walls are less discrete compared to the more reflective parenchyma
Liver does not increase in size with chronic hepatitis.
Fibrosis may be evident, which may produce ‘soft shadowing’ posteriorly
Changes to liver contour
Cirrhosis
Cirrhosis is permanent scarring of the liver where normal liver tissue is replaced by scar tissue.
4 types: Alcoholic (Laennec’s) Post-necrotic Biliary Cardiac
3 nodule types:
Micronodular cirrhosis
Macronodular cirrhosis
Mixed cirrhosis
Clinical presentation: Hepatomegaly Jaundice Ascites Nausea Anorexia Weight loss Jaundice Dark urine Fatigue Varicosities
Liver transplantation
- Performed in patients with end-stage liver disease when more conservative medical and surgical treatments have failed.
- Presence of portal vein thrombosis is a predictor of a higher risk in these transplant patients.
Post-op ultrasound presentation / complications: Ascites Portal vein thrombus Bile duct leakage or atresia Infection Rejection of donor liver Liver failure of donor liver
Role of ultrasound: Confirm patent arterial flow Confirm patent hepatic vein flow Confirm patent portal vein flow Confirm bile duct appearance
Hepatic trauma
Laceration of the liver can occur following blunt force trauma (i.e. car accident) or penetrating foreign object (i.e. knife, broken rib).
A hematoma can occur around and/or within the liver following trauma, especially after a laceration
The right lobe is affected more often than the left – why?
Glisson’s capsule
- Inner layer of connective tissue layer over the liver and surrounding the portal triad within the liver
- Outer layer of liver capsule is the peritoneum
** Can be the cause of RUQ pain with an enlarged liver **
Can differentiate from Murphy’s sign by pressing transducer over several areas of capsule and not just the GB fossa
Simple Cysts
- Cause unknown
- Benign
- Anechoic fluid
- Well circumscribed
- Thin-walled
Polycystic liver disease (PLD)
Genetic disease
Most often assoc. with autosomal dominant polycystic kidney disease (ADPKD)
Multiple cysts throughout the liver
Hydatid cysts
- Mainly caused by infection with the larval stage of the dog tapeworm Echinococcus granulosus
- Eggs excreted in faeces of infected dogs
- Larvae hatch in the duodenum and make their way up through the sphincter of Oddi
- Mainly affects the liver (50-70%) but can affect other abdo organs like kidneys, spleen, pancreas, and even the gallbladder
- Hydatid cysts can grow for a long time before symptoms occur
- When they are large, can cause nausea, weakness, coughing, and stomach or chest pain
Cystadenoma
- Make up 5% of cystic lesions in the liver
- More common in women
- Symptoms can include abdo pain, post-prandial epigastric pain / discomfort, nausea
- Can be incorrectly diagnosed as simple cysts
- Multiloculated often
Cystadenocarcinoma
- Malignant version of a cystadenoma
- Grows from biliary epithelium – cystic collections of secretions are formed
- Can become invasive with local and metastatic extension
Can be hard to differentiate between cystadenoma and cystadenocarcinoma on ultrasound – both multiloculated, CAC have intracystic solid areas
Hepatic abscess
Poorly demarcated
Variable appearance
May have gas present
S&S – hepatic abscess: Pain RUQ Chest pain (RHS) Fever, chills, night sweats N/V/LOA Unintentional Wt Loss
Hemangioma
Benign
Most prevalent tumour of the liver
Often asymptomatic
Well circumscribed, echogenic (mostly) solid lesions
Mostly show no internal colour Doppler flow
Larger hemangiomas may cause pain / discomfort
Focal nodular hyperplasia
- Benign with no malignancy potential
- Second most prevalent tumour of the liver
- Arises from a pre-existing arteriovenous malformation in the liver
- Often asymptomatic
- Well circumscribed, isoechoic or hypoechoic solid lesions
- Rarely grow or bleed
- Hypervascular
