The four stages of liver disease are inflammation, fibrosis, cirrhosis and liver failure, according to the American Liver Foundation. Whether the liver is infected, injured by toxins such as alcohol or chemicals, or under attack from a patient's own immune system, liver disease progresses in much the same way.
In the early stage of liver disease, the liver becomes inflamed and may become tender and enlarged. In some cases, however, an inflamed liver may cause no discomfort at all. Inflammation is a warning sign that the body is trying to fight an infection or heal an injury, explains the American Liver Foundation. The prognosis is good at this stage, but if left untreated, the inflamed liver starts to scar, and excess scar tissue replaces healthy liver tissue. This process, called fibrosis, forces the liver to work harder since blood flow may be restricted.
When the damage from scarring becomes irreversible, the cirrhosis stage has begun. Cirrhosis may lead to serious complications, including liver cancer. In the final stage of liver disease, liver failure, the liver loses all function. This is a life-threatening condition that demands urgent medical care, warns the American Liver Foundation. Symptoms of liver failure may include nausea, loss of appetite, fatigue and diarrhea, with symptoms growing more serious as the stage progresses.