The liver is an essential organ that has many functions in the body, including making proteins and blood clotting factors, manufacturing triglycerides and cholesterol, glycogen synthesis, and bile production.
The liver is a large organ that sits on the right hand side of the belly.
The liver is the body's largest internal organ.
Many different disease processes can occur in the liver, including infections such as hepatitis, cirrhosis (scarring), cancers, and damage by medications or toxins.
The liver has multiple functions. It makes many of the chemicals required by the body to function normally, it breaks down and detoxifies substances in the body, and it also acts as a storage unit.
Hepatocytes (hepar=liver + cyte=cell) are responsible for making many of the proteins (protein synthesis) in the body that are required for many functions, including blood clotting factors, and albumin, required to maintain fluid within the circulation system. The liver is also responsible for manufacturing cholesterol and triglycerides. Carbohydrates are also produced in the liver and the organ is responsible for turning glucose into glycogen that can be stored both in the liver and in the muscle cells. The liver also makes bile that helps with food digestion.
The liver plays an important role in detoxifying the body by converting ammonia, a byproduct of metabolism in the body, into urea that is excreted in the urine by the kidneys. The liver also breaks down medications and drugs, including alcohol, and is responsible for breaking down insulin and other hormones in the body.
The liver is also stores vitamins and chemicals that the body requires as building blocks. These includes:
Symptoms of liver disease can include
The liver is one of the vital organs of the body, responsible for hundreds of chemical actions that the body needs to survive. It is also a gland because it secretes chemicals that are used by other parts of the body. For these reasons the liver is both an organ and a gland; in fact, it is the largest internal organ in the body.
Many diseases may affect the liver directly or as a consequence of an illness or disease that begins in another organ.
Fatty liver disease, caused by accumulation of cholesterol and triglycerides within the liver is not associated with alcohol abuse. Fatty liver disease is also referred to as nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH).
Cirrhosis of the liver describes a condition of scarring in the liver that is not reversible and may lead to liver failure.
Alcohol abuse causes cirrhosis of the liver and is the most common cause of liver disease in North America.
Hepatitis is an infection of the liver that causes liver inflammation.
Infections may affect the liver, including:
Genetic disorders can affect the liver, examples include the following:
Abnormalities of bile flow from the liver may lead to liver inflammation, for example:
Decrease in blood flow draining out of the liver may cause the liver to become congested and inflamed, two examples include:
Congestive heart failure (CHF) is a condition in which the heart is not strong enough to pump all of the blood it receives, and that blood can back up into the liver.
Budd Chiari syndrome is a disease in which blood clots form in the hepatic veins, preventing blood from leaving the liver.
The liver is located in the abdomen but the health care professional will want to examine the whole body to look for the consequences of liver disease.
The abdomen may be palpated to feel for an enlarged liver. As it grows, the liver edge may be felt below the right rib margin. An inflamed liver in acute hepatitis may be tender but a liver that is cirrhotic, small and shrunken, may not be able to be felt.
If liver disease is a consideration, the health care professional also may feel for an enlarged spleen and assess whether excess fluid is present in the abdomen (ascites), perhaps indicating the presence of portal hypertension.
The skin, including the sclera of the eyes, may be assessed for color looking for jaundice. Spider nevi, or angiomata, are a collection of blood vessels under the skin and may be normal, but in the proper setting may indicate liver disease.
If the person is confused (hepatic encephalopathy), the doctor may attempt to illicit asterixis, or flap on the physical examination. These people may not be able to keep their wrists cocked when their arms are held outstretched but instead see their wrists rhythmically flapping.
Blood tests may be ordered to help make the diagnosis. Liver enzymes levels may reveal liver inflammation. However, in patients with end-stage liver disease, the liver can burn itself out and the enzymes may be normal even in the face of severe disease. Other blood tests that may be appropriate include a complete blood cell count (CBC), hepatitis virus screen, and blood clotting tests (a sensitive way to measure function since the liver is responsible for manufacturing the proteins involved in the blood clotting mechanism).
On occasion, ultrasound may be helpful in assessing the anatomy of the liver and this may lead to other tests including CT scan to further assess the anatomy and structure of the liver and surrounding tissues.
Most often, diseases of the liver can be diagnosed by history, physical examination, and blood tests. On occasion, should the diagnosis be unclear or to assess the degree of damage to the liver, a liver biopsy may be necessary.
Using a very thin needle, a gastroenterologist or hepatologist (two types of liver specialists) or an interventional radiologist will insert a very fine needle through the skin and into the liver, to retrieve a small bit of tissue. This can then be examined under the microscope by a pathologist to help make the diagnosis. This procedure is done under sterile conditions to prevent infection, and a local anesthetic is injected into the skin to decrease the potential for pain.
If there is concern about only one area of the liver, instead of a disease that would affect the whole organ, an ultrasound may be used to help guide the needle into the proper position.
Moderate alcohol consumption to decrease the risk of the most common cause of liver disease in North America.
The risk of contracting hepatitis B and hepatitis C can be decreased by minimizing exposure to body fluids.
As mentioned previously, vaccinations are available for hepatitis A and B.
Maintain a healthy weight and eat a balanced diet to decrease the risk of developing fatty liver disease.