Your Liver
One of the body's largest solid organs, the adult liver weighs about three pounds. It is located near the stomach, in the upper portion of the abdomen under the rib cage, and is divided into two sections called lobes. The liver is connected to the small intestine by the bile duct.
Bile, produced in the liver, flows through the bile duct to the gallbladder, where it is first stored, and then released into the small intestine after you eat, to help your body digest and absorb fats.
The liver receives blood from two sources: the hepatic artery and the portal vein. The portal vein carries nutrients from the stomach and the intestine to the liver. The hepatic artery carries oxygen from the heart and lungs to the liver. There are also three hepatic veins that return blood from the liver to the heart.
Metabolic Powerhouse
The liver is a factory and a filter. In total, the liver performs more than 400 different functions in healthy adults, chief among them:
- Production of bile, which allows the body to digest and absorb proteins, fats and carbohydrates
- Production of blood-clotting substances
- Production of blood proteins and approximately 1,000-plus enzymes
- Using and storing minerals and vitamins
- Stockpiling glycogen, or energy, to fuel muscles
- Regulating several hormones and maintaining normal concentration of blood sugar
- Detoxification of many substances
The liver purifies and metabolizes (that is, changes into energy and nutrients) various medications. It neutralizes toxins or poisons, such as alcohol or drugs. The liver also removes bacteria that you might have unknowingly eaten or absorbed.
The liver has an amazing ability to regenerate, or make new liver tissue. However, extensive damage to liver cells, from illness or injury, can lead to scarring, which can interfere with tissue regeneration and function.
Liver Failure: Chronic and Acute
Liver failure occurs when the liver does not perform as it should. Chronic liver disease is an ongoing liver injury that lasts more than six months. It can lead to fibrosis, where the liver, to compensate for the injury, replaces normal tissue with fibrous tissue. Fibrosis, in turn, can progress to cirrhosis. Cirrhosis causes broad bands of scarring tissue to develop, and surround, regenerating liver tissue. The progressive scarring destroys liver cell function and can lead to many serious complications such as portal hypertension (high blood pressure within the liver), ascites (fluid buildup within the abdomen), and intestinal bleeding.
Acute injury, on the other hand, is a brief but very severe insult to the liver that generally resolves itself. However, some people suffer an acute injury that is so severe that it leads to liver failure.
Liver Disease
There are many diseases that can affect the liver's ability to function properly:
- Toxins, alcohol, poor diet or infection can damage the liver
- Inherited disorders may affect liver function by causing harmful substances, such as iron and copper, to collect in the liver
- Viral infections, such as hepatitis A, B, C, D and E, can cause liver cell inflammation, cell death and ultimately lead to liver destruction or scarring
- Tumors in the liver or bile ducts
Some of these diseases work quickly - in just days or weeks - while others take years to do damage.
Diagnosis
One of the many challenges of liver disease is that people can have chronic liver illness for many years without ever having any symptoms. When symptoms do present, the disease may already be very advanced. Typical signs and symptoms of liver disease can include:
- Weight loss
- Eyes and skin turning yellow (jaundice)
- Severe itching
- Dark or tea-colored urine
- Encephalopathy (inability to concentrate, memory loss and insomnia)
- Vomiting blood or passing bloody stools (bowel movements)
- Bruising easily
- Having a tendency to bleed
- Gray, clay-colored or white stools
- Buildup of fluid in the abdomen (ascites) or in the legs (edema)
- Frequent infections
Live Expertise at BIDMC
The Transplant Institute works closely with staff from Beth Israel Deaconess' world-class Liver Center, which offers multidisciplinary treatment for adults with acute and chronic liver diseases. The Liver Center is also the leading site on the East Coast for developing new therapies for patients with all forms of viral hepatitis.
Transplant Institute staff also see patients in BIDMC's premier Liver Tumor Center. This center provides a full range of radiological, surgical, medical and oncological expertise for patients with all varieties of liver tumors.
Liver Transplantation
A liver transplant may be considered as a treatment option for people with advanced liver disease, who have deteriorating liver function and quality of life, and who are unable to benefit from other medical and surgical treatments.
For a more detailed and clinical explanation about all facets of liver transplantation, read the chapter authored by BIDMC transplant surgeon Dr. Douglas W. Hanto, division chief, and Scott Johnson in the Surgery: Basic Science and Clinical Evidence, 2nd Edition textbook published by Sprinter-Verlag Inc (2007).