Hepatitis is a disease of the liver characterized by the presence of inflammation. Hepatitis may occur without symptoms. Symptoms if present may include a yellow discoloration of the skin and of the whites of the eyes, poor appetite, and feeling tired. Hepatitis can be an acute or a chronic disease. Acute hepatitis can sometimes resolve on its own, progress to chronic hepatitis, or rarely can cause acute liver failure. Chronic hepatitis may have no symptoms, or may progress over time to cirrhosis (scarring of the liver), fibrosis (the formation of extra fibrous connective tissue), and chronic liver failure. Cirrhosis of the liver increases the risk of developing hepatocellular carcinoma (a form of liver cancer).
Worldwide, viral hepatitis is the most common cause, followed closely by alcoholic liver disease and non-alcoholic fatty liver disease (NAFLD). Other less common causes of hepatitis include autoimmune diseases, poisoning especially through toxication, certain medications (such as paracetamol), some industrial organic solvents, and plants.