Liver disease is a term for a collection of conditions, diseases, and infections that affect the cells, tissues, structures, or functions of the liver.
What is going on in the body?
The liver is an important organ located in the upper right quadrant of the abdomen. It is responsible for:
filtering the blood
making bile, a substance that helps digest fat and excrete certain fatty substances
processing and hooking fats to carriers (including cholesterol), and storing sugars, helping the body transport and save energy.
making important proteins, such as most of those involved in blood clotting
metabolizing many medications, such as barbiturates, sedatives, and amphetamines
storing iron, copper, vitamins A and D, and several of the B vitamins
making important proteins like albumin that regulate fluid transport in the blood and kidneys.
- helping break down and recycle red blood cells
If the liver becomes inflamed or infected, its ability to perform these functions may be impaired. Liver disease and infections are caused by a variety of conditions including viral infections, bacterial invasion, and chemical or physical changes within the body. The most common cause of liver damage is malnutrition, especially that which occurs with alcoholism.
Symptoms of liver disease may be acute, occurring suddenly, or chronic, developing slowly over a long period of time. Chronic liver disease is much more common than acute. The rates of chronic liver disease for men are two times higher than for women. Liver disease may range from mild to severe depending on the type of disease present.
What are the causes and risks of the disease?
Liver disease can be caused by a variety of factors. Causes include:
- congenital birth defects, or abnormalities of the liver present at birth
- metabolic disorders, or defects in basic body processes
- viral or bacterial infections
- alcohol or poisoning by toxins
- certain medications that are toxic to the liver
- nutritional deficiencies
- trauma, or injury
Liver diseases most likely to be seen in children include:
galactosemia, an inherited disease in which the body can not tolerate certain sugars in milk. These sugars can build up, causing serious damage to the liver and other organs of the body.
Alagille's syndrome, a condition in which the bile ducts narrow and deteriorate, especially during the first year of life
alpha 1- antitrypsin deficiency, a genetic liver disease in children that can lead to hepatitis and cirrhosis of the liver
neonatal hepatitis, which is hepatitis that occurs in a newborn during the first few months of life
tyrosinemia, a disorder that causes serious problems with liver metabolism
hemorrhagic telangiectasia, a condition in which thin blood vessels allow frequent and easy bleeding of the skin and digestive tract
Reye's syndrome, a condition that causes a buildup of fat in the liver. This condition has been linked in some cases to use of aspirin, especially in conjunction with chickenpox, influenza, or other illnesses with fever.
Wilson's disease, an inherited condition that causes a buildup of the mineral copper in the liver
thalassemia, a group of hereditary anemias, or low red blood cell counts
biliary atresia, a condition in which the bile ducts extending from the liver to the intestine are too small in diameter or are missing
chronic active hepatitis, an inflammation of the liver that causes severe scarring and interference with liver function
cancer of the liver, which may result from cancer in other parts of the body that have spread to the liver
Liver diseases most likely to be seen in adults include:
cirrhosis, which is a serious condition that causes tissues and cells in the liver to be replaced by scar tissue.
type I glycogen storage disease, which causes problems in controlling blood sugars when a person fasts
porphyria, a condition that causes a malfunction in how the body uses porphyrins.
Porphyrins are important in making hemoglobin in red blood cells, to carry oxygen throughout the body.
hemochromatosis, a condition which causes the body to absorb and store too much iron. The iron buildup causes damage to the liver and other organs.
primary sclerosing cholangitis, a condition that causes the bile ducts of the liver to narrow due to inflammation and scarring
sarcoidosis, a disease that causes a buildup of lesions within the liver and other organs of the body
gallstones, which may block the bile duct
hepatitis, an inflammation and infection of the liver caused by any of several viruses
- cystic disease of the liver, which causes lesions and fluid-filled masses in the liver
Alcohol-related liver diseases include:
What can be done to prevent the disease?
Some, but not all, liver diseases can be prevented. For example, hepatitis A and hepatitis B can be prevented with vaccines.
Other ways to decrease the risk of infectious liver disease include:
practicing good hygiene, such as washing hands well after using the restroom or changing diapers
avoiding drinking or using tap water when traveling internationally
avoiding illegal drug use, especially sharing injection equipment
practicing safest sex. Practicing safer sex provides less protection.
avoiding the sharing of personal hygiene items, such as razors or nail clippers
avoiding toxic substances and excess alcohol consumption
using medications only as directed
using caution around industrial chemicals
eating a well balanced diet following the food guide pyramid
getting an injection of immune globulin after exposure to hepatitis A
using recommended safety precautions in healthcare and day care work
How is the disease diagnosed?
A healthcare professional can determine whether a person's symptoms, medical history, and physical exam are consistent with liver disease. Hepatomegaly, an enlarged, firm liver, and other signs of liver disease may be found on examination.
Many further tests may also be used to support the diagnosis. These include blood tests, such as:
liver function tests, which are blood tests that check a wide variety of liver enzymes and byproducts
a complete blood count (CBC), which looks at the type and number of blood cells in the body
ultrasounds, to show size of abdominal organs and the presence of masses
an upper GI study, which can detect abnormalities in the esophagus caused by liver disease
liver scans with radiotagged substances to show changes in the liver structure
ERCP, or endoscopic retrograde cholangiopancreatography. A thin tube called an endoscope is used to view various structures in and around the liver.
- abdominal CT scan or abdominal MRI, which provide more information about the liver structure and function
In some cases, the only way to definitively diagnose the presence of certain liver diseases is by a liver biopsy. This procedure involves the removal of a tiny piece of liver tissue for examination under a microscope. Liver biopsies may have to be done repeatedly to see how the disease is progressing or responding to treatment.
Long Term Effects
What are the long-term effects of the disease?
Long- term effects depend on the type of liver disease present. For example, chronic hepatitis can lead to:
cirrhosis of the liver
- illnesses in other parts of the body, such as kidney damage or low blood counts
Other long-term effects of liver disease may include:
gastrointestinal bleeding. This includes bleeding esophageal varices, which are abnormally enlarged veins in the esophagus and/or the stomach.
encephalopathy, which is deteriorating brain function that may progress to a coma
peptic ulcers, which erode the stomach lining
- liver cancer
What are the risks to others?
Some liver diseases are highly contagious and pose a risk to others. For example, different forms of hepatitis
are highly contagious through sexual contact or contamination of food and water. Other liver diseases are not contagious, such as biliary atresia.
What are the treatments for the disease?
Treatment for liver disease will include:
- bed rest
- drinking extra fluids to prevent dehydration
- avoiding unnecessary medications
- avoiding alcohol
- eating a well balanced diet for liver disease
- taking antinausea medications as needed
Further treatment will depend on the type and the extent of disease. For example, treating hepatitis B, hepatitis C, and hepatitis D may involve the use of medications such as the antiviral medication alpha interferon. Other medications used to treat liver disease may include ribavirin, lamivudine, steroids, and antibiotics.
To treat Wilson's disease, the healthcare professional may prescribe trientine or penicillamine. If these medications cannot be tolerated, the person may be asked to take zinc acetate.
Hemochromatosis is treated by removing a pint of blood once or twice a week for several months to a year, depending on the severity of the condition. This will effectively deplete the excess iron.
Vitamin and mineral supplements are given to prevent complications from primary biliary cirrhosis. These include vitamin A, vitamin D, vitamin E, vitamin K, and calcium. Cholestyramine may be given to help relieve itching.
Biliary atresia may be treated with a procedure called the Kasai surgery, a procedure in which the surgeon replaces the bile ducts with part of the baby's intestine.
Acute fulminant hepatitis can cause life-threatening liver failure. This requires a hospital stay and treatment for the bleeding disorder, encephalopathy, and nutritional problems. Sometimes, the only effective treatment for certain liver diseases is a liver transplant.
What are the side effects of the treatments?
Side effects will depend on the treatments used for the liver disease. Antibiotics may cause stomach upset or allergic reactions. Side effects of interferon include a flu-like illness, with fever, and body aches.
A liver transplant can cause many complications, including failure or rejection of the new liver. After a liver transplant, a person will need to take powerful anti-rejection medications for the rest of his or her life. Because these medications interfere with normal immunes system functioning, they increase the person's risk for infections and certain types of cancer.
What happens after treatment for the disease?
What occurs after treatment will depend on the type of liver disease and the response to treatment. For example, people with hepatitis A will not usually need medication after the disease has been resolved. They can return to a normal lifestyle when symptoms are gone, even if they still have some jaundice.
A person with hepatitis B, hepatitis C, or hepatitis D needs to be monitored for side effects and benefits during and after interferon treatment. Alpha interferon treatment might be repeated if the disease flares up again. A person who has received a liver transplant is checked for further disease, as well as for function of the new liver.
How is the disease monitored?
Monitoring will depend on the type of liver disease. Liver function tests may be performed during periodic visits to the healthcare professional, to monitor the disease and to see how the liver is working. Any new or worsening symptoms should be reported to the healthcare professional. The status of the liver may require repeated liver biopsies. Decisions for further treatment or liver transplantation are frequently made based on these tests.
http://www.liverfoundation.org/html/livheal.dir/livheal.htm/ http://www.niddk.nih.gov/health/digest/pubs/hep/index.htm/ Harrison's Principles of Internal Medicine, fauci et al, 1998