Causes of Liver Disorders

Hepatitis is an inflammation of the liver that can be caused by a virus, by inherited disorders, and sometimes by certain medications or toxins such as alcohol and drugs. 

Scientists have identified four main types of viral hepatitis: hepatitis A, hepatitis B, hepatitis C, and hepatitis D. A fifth type, hepatitis E, is generally not found in North America.

Hepatitis A is waterborne and spread mainly via sewage and contaminated food and water.

Hepatitis B is transmitted by contact with infected semen, blood, or vaginal secretions, and from mother to newborn. Hepatitis B is most commonly spread by unprotected sex and by sharing of infected needles (including those used for tattooing, acupuncture, and ear piercing).

Hepatitis C spreads via direct blood-to-blood contact.

Hepatitis D is spread by infected needles and blood transfusions.

Improved screening of donated blood has greatly reduced the risk of catching hepatitis B or C from blood transfusions. Both hepatitis B and C can be spread through sharing of razors, toothbrushes, and nail clippers.

The main cause of cirrhosis is chronic infection with the hepatitis C virus. Other causes include:

• long-term, excessive alcohol consumption
• chronic infection with hepatitis B virus
• inherited disorders of iron and copper metabolism
• severe reactions to certain medications
• fatty liver caused by obesity
• infections from bacteria and parasites usually found in the tropics
• repeated episodes of heart failure with liver congestion and bile-duct obstruction

With cirrhosis, the liver tissue is irreversibly and progressively destroyed as a result of infection, poison, or some other disease. Normal liver tissue is replaced by scars and areas of regenerating liver cells.