Types of Liver Disease Flashcards
How many different types of liver disease are there?
200 types
What is the prevalence of liver disease in the UK?
2 million, with the prevalence increasing
What are the main causes of LD?
Obesity
Alcohol - the main cause
Undiagnosed hepatitis infection
Drug or other chemical toxicity
State the different types of LD?
Alcohol related liver disease
Drug induced hepatoxicity
Hepatitis
Non-alcoholic fatty liver disease
Cirrhosis
Cancer
Gallstones
Cholangitis
Hemochromatosis
Wilson’s disease
Gilbert’s disease
What are the main causes of hepatitis?
Mainly viral causes - in particular Hepatitis B and C can cause long-term inflammation
Other causes include:
Heavy alcohol use
Toxins
Drug induced
Autoimmune disease
What is non-alcoholic fatty liver disease?
It is a term used for a range of conditions caused by a build of fat within the liver and is usually seen in patients that are overweight or obese. Fat is usually stored in the adipose but the liver does have some capability to also store some fat. In fatty liver large vacuoles of TG accumulate in hepatocytes via steatosis.
Early stage fatty liver disease is not harmful but in later stages can progress to cirrhosis.
What percentage of US adults have fatty liver?
It is believed to affect 20-30% of US adults.
Describe the potential progression of fatty liver disease?
Increased TG deposition within hepatocytes results in a ‘fatty liver’ indicated by increased TG and LFTs, alongside liver fat.
15-20% then develop non-alcohol fatty liver disease resulting in inflammation and fibrosis of the liver which can then develop into cirrhosis and then potentially a hepatocellular carcinoma.
What are gallstones?
Gallstones are deposits of hardened, solidified substances found in bile such as cholesterol which are abnormally formed within the gallbladder or bile duct. This can block bile secretion from the liver known as bile duct obstruction and cause of a backlog causing infection and inflammation possibly resulting in acute cholecystitis (inflammation of the gallbladder wall).
However most cases of gallstones don’t present with symptoms and do not need to be treated (may not cause complete biliary obstruction).
What are the risk factors for gallstones?
Being overweight or obese
Female (particular if you have children)
Increasing age
What is Cholangitis?
Cholangitis is inflammation of the bile duct, this is different for cholecystitis which is inflammation of the gallbladder wall. However presence of gallstones does increase the risk of cholangitis occurring. Again this can cause narrowing of the bile duct leading to complications.
What are the risk factors for Cholangitis?
Aside from gallstones other risk factors include:
Having autoimmune diseases such as inflammatory bowel disease (ulcerative colitis or Crohn’s disease)
Recent medical procedures involving the bile duct area
Having human immunodeficiency virus (HIV)
Traveling to countries where you might be exposed to worms or parasites
What is hemochromatosis?
This is an inherited condition which causes your body to absorb too much iron from the food you eat. When untreated this can result in iron deposition in tissue and organs including the liver, heart and pancreas resulting in complications.
What is Wilson’s disease?
Another rare inherited condition which causes copper overload due to the inability of the liver to process and eliminate copper. The accumulated copper within hepatocytes causes inflammation, damage and in some cases scarring (fibrosis) in your liver, known as hepatitis which in some cases can develop into cirrhosis.
What is Gilbert’s syndrome?
Gilbert’s syndrome (GS) is a condition in which you have higher than normal amounts of bilirubin in your blood, also known as unconjugated hyperbilirubinemia. The syndrome is relatively common (1/20 are affected) and is due to the inability of the liver to metabolise bilirubin.
Describe the differences between acute and chronic liver disease.
Acute LD is generally caused by viruses or drug causing damage to hepatocytes and inflammation. However in acute LD (less than 6 months) the ability of hepatocytes to regenerate very efficient and therefore any inflammation resolves within a couple of weeks. However in some cases (such as paracetamol induced hepatoxicity) the extent of damage to hepatocytes is too severe and can be fatal.
Chronic LD is defined by inflammation persistent for over 6 months resulting in permanent damage with structural changes to hepatocytes leading to cirrhosis and can lead to liver cancer. Unlike acute LD the most common cause of Chronic LD is alcohol abuse.
Describe the first stage of progression of liver damage.
Liver disease begins with a chronic injury, damaging hepatocytes and leading to the recruitment of pro-inflammatory cytokines resulting in matrix deposition. There is also cell death of hepatocytes and other cells present in the liver lobules, in angiogenesis occurs. This develops into early fibrosis.
What are some of the possible causes of chronic injury resulting in the first stage of LD?
Viral infection
Alcohol
Non-alcoholic steatohepatitis
Autoimmune disorders
Cholestatic disorders
Metabolic diseases
Following early fibrosis what is the next stage in Liver disease?
In early fibrosis, hepatocytes begin to die/loss of function and are unable to regenerate fully (known as aberrant hepatocytes regeneration). Due to matrix deposition disrupted architecture occurs these structural changes resulting in cirrhosis of the liver potentially causing liver failure and portal hypertension.
Hepatocellular carcinoma can also occur in late stage liver disease, and at this stage the only treatment is a liver transplant.
Which stages of Liver Disease is the damage reversible?
Up to early fibrosis of the liver, treating the underlying cause (such as weight loss in fatty liver) or by treatment of anti-fibrotic drugs, resolution can occur with physiology returning to that of a healthy liver.
These same treatment strategies don’t achieve the same results when it is damaged has progressed to cirrhosis, but some regression can occur.