The liver is the largest internal organ in the body. Its main functions are to:
- metabolize most of the nutrients that are absorbed by the intestine
- store nutrients
- produce proteins
- detoxify blood by removing medications, alcohol, and potentially harmful chemicals from the bloodstream and treating them chemically so they can be excreted by digestive or urinary systems
Because the liver comes in close contact with many harmful substances, it is protected against disease in two main ways. First, it can regenerate itself by repairing or replacing injured tissue. Second, the liver has many cell units responsible for the same task. Therefore, if one area is injured, other cells will perform the functions of the injured section indefinitely or until the damage has been repaired.
Different types of liver disorders include hepatitis, cirrhosis, liver tumours, and liver abscess (collection of pus), just to name a few. The focus here will be the two most common forms: hepatitis and cirrhosis.
There is more than one type of hepatitis, and although they have similar symptoms, they're contracted in very different ways.
Hepatitis A is the most common and the most infectious, spreading easily from person to person like most other viruses. It affects millions around the world and is responsible for more than 2 million deaths a year.
Hepatitis B is acquired through exposure to infected blood, vaginal fluids, or semen. It's estimated that about 350,000 Canadians have hepatitis B.
Hepatitis C affects about 3.5 million North Americans. About 15% of those with hepatitis C may have been exposed to infected blood products before widespread blood testing began.
Hepatitis D is unique because it can only affect those that already have hepatitis B.
The second type of liver disorder is called cirrhosis. This occurs over time. As the liver is damaged, it will repair itself, but scar tissue forms in the process. Over time this makes it difficult for the liver to function. It's the final stage of many different forms of liver disease.
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 is 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.
One of the main causes 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. This is generally permanent, and only reversible in rare cases.
Symptoms and Complications
Both hepatitis and cirrhosis show few warning signs. In the acute phase of most forms of hepatitis, there are flu-like symptoms such as tiredness, fever, nausea, loss of appetite, and pain (usually under the ribs on the right side of the abdomen). There may also be some jaundice (yellowing of the skin and whites of the eyes.)
Following the acute stage, hepatitis A will be cleared from the body and lifelong immunity develops. In hepatitis B and C, viral particles may linger in the body producing a chronic infection that lasts for years. This can eventually lead to liver cirrhosis and, in some cases, liver cancer.
Signs and symptoms of cirrhosis include:
- abdominal pain
- bruising or bleeding easily
- general fatigue
- intestinal bleeding
- jaundice (yellowing of the skin and eyes)
- loss of interest in sex
- nausea and vomiting
- small red, spider-like blood vessels under the skin or easy bruising
- swelling in the abdomen and legs caused by fluid accumulation
- weight loss
If you have cirrhosis, you should seek emergency help if you experience any of the following:
- mental confusion
- rectal bleeding
- slurred speech
- vomiting blood
Making the Diagnosis
Doctors diagnose hepatitis with blood tests and a complete personal history. They will ask if you have:
- used intravenous drugs
- recently eaten shellfish from polluted waters
- travelled to countries where hepatitis infections are common
- had a blood transfusion or been in contact with fresh blood
- had potentially risky sexual practices
- taken certain medications in the past few months
Diagnosing cirrhosis is based on your clinical or medical history and appearance, and blood test results. A liver biopsy may also be performed to confirm the diagnosis.
Treatment and Prevention
There is no specific treatment for acute hepatitis. Bed rest isn't always essential, although you may feel better if you limit your amount of physical activity. It is important to maintain an adequate intake of calories. Your doctor may recommend small, frequent high-calorie meals, with plenty of fluids. Alcohol should be avoided or limited in order to help the liver recover. If you are unable to eat or drink, you may be hospitalized.
Some people with chronic hepatitis B or C may benefit from medications that can slow the replication (reproduction) of the virus to decrease the amount of virus in the body. The risks and benefits of these medications should be discussed with your doctor.
With hepatitis B or C, your doctor may check blood periodically for a few months to watch for any continuing signs of inflammation in the liver. It isn't usually necessary to isolate people with hepatitis, but those who are close to someone with hepatitis should be aware of how the virus spreads. Hand-washing after going to the bathroom is very important.
There are a number of ways that governments and health professionals are fighting the spread of hepatitis. For example, there's an effective vaccination for hepatitis A. Global immunization programs exist against hepatitis B, and screening of blood donations is now common practice to check for hepatitis C. In Canada, hepatitis B vaccination is recommended for the entire population and is included as one of the primary series of vaccinations for infants. If you are travelling to countries where hepatitis is common, check with your doctor or travel medicine clinic to see if you are a candidate for hepatitis A or B immunization. There is no immunization against hepatitis C.
To prevent the spread of viral hepatitis, thorough hand-washing by medical personnel who come into contact with contaminated utensils, bedding, or clothing is critical. Health care workers should be vaccinated, as they are at higher risk for infection due to exposure to people who are infected.
While there are no effective treatments for liver cirrhosis, its progression can be greatly reduced by complete abstinence from alcohol. Caution should also be taken when considering the use of medications, including over-the-counter and herbal medications, that can worsen liver disease. For example, people with cirrhosis should discuss with their doctor how much acetaminophen* they can take safely because acetaminophen is metabolized by the liver. Sometimes anti-inflammatory medications need to be avoided.
Treatment is mainly focused on complications and may include salt restriction to combat fluid retention, diuretic medications ("water pills" that help get rid of excess water in the body), at times a low-protein diet, and vitamin supplements such as vitamins K, A, and D. Itching may be controlled with special medications. Laxatives may be prescribed to speed up removal of toxins from the system. In some cases, a liver transplant may be necessary.