There are many conditions that can harm the liver. And some even cause permanent damage.

The most common reason for permanent damage and the eventual need for a liver transplant is a condition called "cirrhosis." Many different types of liver injuries can cause cirrhosis. In each of these cases, healthy liver cells become damaged. When the cells are first damaged, the immune system sends in special white blood cells in response to the injury. This often causes the liver cells to swell, and this process is called "inflammation."

As the liver tries to repair itself, it can form scar tissue. When large areas of the liver are covered by scar tissue, it's called cirrhosis. Cirrhosis can happen as the result of many long-term liver conditions, like viral hepatitis or drug and alcohol abuse. Cirrhosis can also be caused by fatty buildup on the liver or other conditions that people are born with.

The scarred and damaged liver is at risk for developing cancers. If left untreated, these cancers can spread inside the person with cirrhosis - and even cause death - before the liver completely fails.

No matter what the cause is, when too much of the liver is permanently damaged, waste and poisons can no longer be filtered, nutrients can't be processed, and fuel cannot be stored. If this happens, a liver transplant is the best way to treat it.