The liver is the body’s second largest organ; it performs many essential functions related to digestion, metabolism, immunity and the storage of nutrients within the body. These functions make the liver a vital organ without which the tissues of the body would quickly die from lack of energy and nutrients.
The liver provides storage of many essential nutrients, vitamins, and minerals obtained from blood passing through the hepatic portal system. Glucose is transported into hepatocytes under the influence of the hormone insulin and stored as the polysaccharide glycogen. Hepatocytes also absorb and store fatty acids from digested triglycerides allowing the liver to maintain the homeostasis of blood glucose. Our liver also stores vitamins and minerals in order to provide a constant supply of these essential substances to the tissues of the body.
The liver plays an active role in the process of digestion through the production of bile. Bile travels through the bile ducts and is released into the duodenum where it emulsifies large masses of fat. The emulsification of fats by bile turns the large clumps of fat into smaller pieces that have more surface area and are therefore easier for the body to digest.
Hepatitis is an inflammation of the liver. The condition can be self-limiting or can progress to fibrosis (scarring), cirrhosis or liver cancer. Hepatitis viruses are the most common cause of hepatitis in the world. There are 5 main hepatitis viruses, referred to as types A, B, C, D and E. In particular, types A, B and C are the most common viral hepatitis.
Prevention of viral hepatitis is possible through vaccination for children or adults, following good personal hygiene with regular handwashing, and avoiding the consumption of contaminated food and water. Extramarital affairs and the use of drugs should be avoided. You should never share personal items such as toothbrushes, razor blades, nail clippers, towels and soaps.
Good personal hygiene practices are keys to preventing infection
Hepatitis A is a viral liver disease that can cause mild to severe illness. The hepatitis A virus (HAV) is transmitted through ingestion of contaminated food and water or through direct contact with an infectious person. A safe and effective vaccine is available to prevent hepatitis A. The disease is closely associated with unsafe water or food, inadequate sanitation and poor personal hygiene. Unlike hepatitis B and C, hepatitis A infection does not cause chronic liver disease and is rarely fatal, but it can cause debilitating symptoms and fulminant hepatitis (acute liver failure), which is often fatal.
Almost everyone recovers fully from hepatitis A with a lifelong immunity. However, a very small proportion of people infected with hepatitis A could die from fulminant hepatitis. 15% of people affected by hepatitis A can have symptoms that last for weeks or months until they recover from the illness and return to work, school, or daily life.
Symptoms of hepatitis A range from mild to severe, and can include fever, malaise, loss of appetite, diarrhea, nausea, abdominal discomfort, dark-colored urine and jaundice (a yellowing of the skin and whites of the eyes). Not everyone who is infected will have all of the symptoms.
Hepatitis A signs and symptoms, which typically don’t appear until you’ve had the virus for a few weeks, may include:
- Yellowing of the skin and eyes (jaundice)
- Dark urine and clay-colored bowel movements
- Abdominal pain or discomfort, especially in the area of your liver on your right side beneath your lower ribs
- Itching and rash
Anyone who has not been vaccinated or previously infected can get infected with hepatitis A virus. In areas where the virus is widespread, most hepatitis A infections occur during early childhood.
Risk factors in intermediate and high endemicity areas include poor sanitation, lack of safe water, use of recreational drugs, living in a household with an infected person, being a sexual partner of someone with acute hepatitis A infection and travelling to areas of high endemicity without being immunized. There is no specific treatment for hepatitis A. Recovery from symptoms following infection may be slow and may take several weeks or months. Hospitalization is unnecessary in the absence of acute liver failure. Therapy is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhea. Several injectable inactivated hepatitis A vaccines are available internationally. All are similar in terms of how well they protect people from the virus and their side-effects. If you’re traveling in regions where hepatitis A outbreaks occur, peel and wash all fresh fruits and vegetables yourself and avoid raw or undercooked meat and fish. Drink bottled water and use it when brushing your teeth. Don’t drink beverages of unknown purity, with or without ice. If bottled water isn’t available, boil tap water before drinking it.
Hepatitis A vaccine provides protection against infection, and can be given to a person aged 2 years or older. This vaccine is not routinely given to children but is recommended for people at risk of infection or for people who are expected to have serious complications if they are infected. In general, this vaccine does not cause any side effects or serious complications but it may cause pain, swelling and redness at the injection site, you may also have fever, headache or abdominal pain and general weakness. Hepatitis A vaccine is an inactivated (killed) vaccine. You will need 2 doses for long-lasting protection. These doses should be given at least 6 months apart. Children are routinely vaccinated between their first and second birthdays (12 through 23 months of age). Older children and adolescents can get the vaccine after 23 months. Adults who have not been vaccinated previously and want to be protected against hepatitis A can also get the vaccine.
Vaccination is the most important preventive measure
Hepatitis B is a potentially life-threatening liver infection caused by the hepatitis B virus. It is a major global health problem and the most serious type of viral hepatitis. It can cause chronic liver disease, chronic infection and puts people at high risk of death from cirrhosis of the liver and liver cancer. It is not possible, on clinical grounds, to differentiate hepatitis B from hepatitis caused by other viral agents and, hence, laboratory confirmation of the diagnosis is essential. A number of blood tests are available to diagnose and monitor people with hepatitis B. They can be used to distinguish acute and chronic infections.
In highly endemic areas, hepatitis B is most commonly spread from mother to child at birth, or through horizontal transmission (exposure to infected blood), especially from an infected child to an uninfected child during the first 5 years of life. The development of chronic infection is very common in infants infected from their mothers or before the age of 5 years. It is also spread by percutaneous or mucosal exposure to infected blood and various body fluids, as well as through saliva, menstrual, vaginal, and seminal fluids. Sexual transmission of hepatitis B may occur, particularly in unvaccinated men who have sex with men and heterosexual persons with multiple sex partners or contact with sex workers. Infection in adulthood leads to chronic hepatitis in less than 5% of cases. Transmission of the virus may also occur through the reuse of needles and syringes either in health-care settings or among persons who inject drugs. In addition, infection can occur during medical, surgical and dental procedures, through tattooing, or through the use of razors and similar objects that are contaminated with infected blood. Most people do not experience any symptoms during the acute infection phase. However, some people have acute illness with symptoms that last several weeks, including yellowing of the skin and eyes (jaundice), dark urine, extreme fatigue, nausea, vomiting and abdominal pain. A small subset of persons with acute hepatitis can develop acute liver failure, which can lead to death. In some people, the hepatitis B virus can also cause a chronic liver infection that can later develop into cirrhosis (a scarring of the liver) or liver cancer.
There is no specific treatment for acute hepatitis B. Therefore, care is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids lost from vomiting and diarrhea. Chronic hepatitis B infection can be treated with medicines, including oral antiviral agents. Treatment can slow the progression of cirrhosis, reduce incidence of liver cancer and improve long term survival. WHO recommends the use of oral treatments – tenofovir or entecavir, because these are the most potent drugs to suppress hepatitis B virus. They rarely lead to drug resistance as compared with other drugs, are simple to take (1 pill a day), and have few side effects so require only limited monitoring. The hepatitis B vaccine is the mainstay of hepatitis B prevention. WHO recommends that all infants receive the hepatitis B vaccine as soon as possible after birth, preferably within 24 hours. A 3-dose schedule of hepatitis B vaccine, with the first dose being given at birth and the second and third given at the same time as the first and third doses of diphtheria, pertussis (whooping cough), and tetanus – (DTP) vaccine; or a 4-dose schedule, where a monovalent birth dose is followed by three monovalent or combined vaccine doses, usually given with other routine infant vaccines.
Hepatitis C is a liver disease caused by the hepatitis C virus; the virus can cause both acute and chronic hepatitis, ranging in severity from a mild illness lasting a few weeks to a serious, lifelong illness. The hepatitis C virus is a bloodborne virus and the most common modes of infection are through exposure to small quantities of blood. This may happen through injection drug use, unsafe injection practices, unsafe healthcare, and the transfusion of unscreened blood and blood products. Hepatitis C virus (HCV) causes both acute and chronic infection. About 15–45% of infected persons spontaneously clear the virus within 6 months of infection without any treatment. The hepatitis C virus is a bloodborne virus. It is most commonly transmitted through injecting drug use through the sharing of injection equipment, the reuse or inadequate sterilization of medical equipment, especially syringes and needles in healthcare settings and the transfusion of unscreened blood and blood products. HCV can also be transmitted sexually and can be passed from an infected mother to her baby; however these modes of transmission are much less common.
The incubation period for hepatitis C is 2 weeks to 6 months. Following initial infection, approximately 80% of people do not exhibit any symptoms. Those who are acutely symptomatic may exhibit fever, fatigue, decreased appetite, nausea, vomiting, abdominal pain, dark urine, grey-coloured faeces, joint pain and jaundice (yellowing of skin and the whites of the eyes).
Due to the fact that acute HCV infection is usually asymptomatic, few people are diagnosed during the acute phase. In those people who go on to develop chronic HCV infection, the infection is also often undiagnosed because the infection remains asymptomatic until decades after infection when symptoms develop secondary to serious liver damage.
As the pressure increases in the blood vessels of the liver, it may lead to fluid buildup in the abdominal cavity, and the esophageal varices are prone to rupture easily and can suddenly bleed. Also, hypertension can cause renal failure or enlarged spleen, thus causing lower blood cells and anemia, or a decrease in the number of platelets which may lead to easy bleeding anywhere in the body.
Hepatitis C virus can make the body produce antibodies that may cause vasculitis, which in turn can damage the skin, joints and kidneys. It can also lead to joint pain, arthritis and a purple rash around the legs, and the Raynaud’s phenomenon in the fingers and toes that become painful in cold temperatures.
The most common symptoms are:
- Exhaustion and tiredness
- Nausea or vomiting
- Loss of appetite
- Dark urine
- Joint or muscle pain
- Unspecified pain or complaints in the abdomen or liver area
- Pale stools
- Jaundice at an advanced stage of hepatitis, and in most cases, jaundice is the result of liver cirrhosis.
The treatment of hepatitis C virus is primarily through antiviral medications to clear the virus from the body at least 12 weeks after completion of treatment. Researchers have reached some therapeutic developments in the past years and found new antiviral drugs that target viruses directly.
In some cases, hepatitis C causes liver cancer or severe damage to the liver, resulting in end-stage liver disease and ultimately liver failure. The only effective treatment for end-stage liver disease is a liver transplant. Liver transplantation is not a cure for HCV. The virus is still in the blood, so HCV returns after the surgery, requiring treatment with antiviral drugs to prevent damage to the implanted liver. Many studies have shown that new antiviral drugs are effective in treating hepatitis after transplantation. This process has seen tangible developments that gave hope to patients. It is now possible to donate liver tissue from a living relative and split the liver into two parts so it can be implanted in two persons instead of one, thus more patients will be able to benefit from it.