Overview

The liver is a vital organ located in the upper right side of the abdomen. It is somewhat larger than the size of a football and weighing about 2-3 pounds, it performs numerous functions for the body: converting nutrients derived from food into essential blood components, storing vitamins and minerals, regulating blood clotting, producing proteins and enzymes, maintaining hormone balance, and metabolizing and detoxifying substances that would otherwise be harmful to the body.

The most important thing to recognize about liver disease is that almost half of individuals with underlying liver disease have no symptoms. The most common symptoms are very non-specific and they include fatigue or excessive tiredness, lack of drive and occasionally itching. Signs of liver disease that are more prominent are jaundice/ yellowing of the eyes and skin, dark urine, very pale or light colored stool or bowel movements, bleeding from the GI tract, mental confusion, and retention of fluids in the abdomen or belly

The liver is an amazing and unique organ. It is the only organ in the body that is able to regenerate, that is completely repair the damage. With most organs, such as the heart, the damaged tissue is replaced with scar, like on the skin. The liver, however, is able to replace damaged tissue with new cells. An extreme example is a patient who suffers an overdose from Tylenol. In this extreme example up to 50 - 60 percent of the liver cells may be killed within 3 - 4 days. However, if no other complications arise, the patient's liver will repair completely, and a liver biopsy after 30 days will appear completely normal with no signs of damage/ no scar. However, the long-term complications of liver disease occur when regeneration is either incomplete or if it is prevented by progressive development of scar tissue within the liver. This occurs when the damaging agent such as a virus, alcohol, etc., continues to attack the liver and hence prevents complete regeneration.

Liver disease is categorized both by the cause and the effect it has on the liver. Causes may include infection, injury, exposure to drugs/ toxic compounds, an autoimmune process, or a genetic defect (such as hemochromatosis). These causes can lead to hepatitis, cirrhosis, stones that develop and form blockages, fatty liver, and in some rare instances liver cancer. Genetic defects can prevent vital liver functions and lead to the deposition and build-up of damaging substances, such as iron/ copper.

There are two major forms of hepatitis: one in which the liver is inflamed quickly (called acute hepatitis) and one in which the liver is inflamed and damaged slowly, over a long period of time (chronic hepatitis). While hepatitis can be caused by any of the means mentioned above, most commonly it is due to infection by one of several viruses, termed hepatitis viruses. These viruses are named in the order of their discovery as hepatitis A, B, C, D, E.

Anything that causes very severe ongoing injury to the liver can lead to cirrhosis. It is marked by cell death/ scar formation and is a progressive disease that creates irreversible damage. Cirrhosis can be treated by trying to limit further damage. Gallstones, tumors, trauma, and inflammation can cause blockages or obstructions in the ducts draining the liver.

Obstruction of the hepatic vein, the vein from the liver, may also occur, reducing blood flow out of the liver. This obstruction may be due to tumors pushing against the vein or from blood clot formation within the vein itself.

Hepatitis or cirrhosis may lead to liver cancer in some cases, but more frequently cancer starts in other parts of the body and then spreads to the liver. When cancer does arise in the liver, it is called primary liver cancer. The most common type is hepatocellular carcinoma, cancer that develops within the liver’s hepatocyte cells.

Hemochromatosis is the most common genetic liver disorder worldwide. It involves excess iron storage and is usually diagnosed in adults. There are numerous genetic liver diseases that affect children also. The most common is alpha 1-antitrypsin deficiency. Most of the genetic liver diseases involve a missing enzyme / protein that leads to damaging deposits in the liver (such as galactosemia, the absence of a milk sugar enzyme).