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 he largest internal organ, the liver literally keeps you alive. It performs over 100 separate bodily functions; and its sheer complexity makes it susceptible to almost as many different diseases. Fortunately, most are rare. But there are a few that are all too common, including hepatitis, cirrhosis, liver disorders in children, alcohol-related disorders, and liver cancer. The American Liver Foundation reports that more than 25 million people are afflicted with liver and gallbladder disease each year. Over 27,000 Americans die from cirrhosis annually, making it the country's third leading cause of death for people between the ages of 25 and 59, and the seventh leading cause of death overall. Viruses, hereditary defects, and reactions to drugs and chemicals are among the known causes of liver breakdown. Though few treatments are effective for life-threatening liver disease, avoiding alcohol and other substances known to cause damage can do a lot to safeguard this important organ. A recently developed vaccine against the hepatitis B virus is now being recommended for children and for adults such as health-care workers who are in danger of exposure. (See section below on viral hepatitis.) The liver is located behind the lower ribs, right below the diaphragm on the right side of the abdomen. In an average-sized man, it is about the size of a football, weighing a little over three pounds. A miniature refinery, the liver processes many chemicals necessary for the body's overall functioning. For example, it converts carbohydrates, fats, and proteins into chemicals essential for life and growth. It manufactures and exports to other organs some of the substances they need to function properly, such as the bile used by the intestines during digestion. It modifies drugs taken to treat disease so that they can be used more easily by the body. And it cleanses the blood of toxic substances either ingested or produced by the body itself. But that's only part of the picture. Below are some of the liver's many other important functions: - Regulates the blood's ability to clot--governs the transport of fat stores
- Stores extra vitamins, minerals, and sugars to prevent shortages
- Produces quick energy as needed
- Controls the production and excretion of cholesterol
- Breaks down alcohol
- Monitors and maintains the right level of numerous chemicals and drugs in the blood
- Maintains and controls hormone balance
- Helps the body resist infection by producing immune factors and cleansing bacteria from the blood
- Stores iron
The Threat of Viral Hepatitis
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Viral hepatitis, a contagious infection of the liver, afflicts more than 70,000 Americans each year. It is usually caused by one of three different organisms. Hepatitis A, formerly known as infectious hepatitis, can be contracted by consuming contaminated water or food, most notably shellfish. Since the virus is eliminated in the stool, it also spreads through improper hand washing, especially by restaurant workers or anyone else who handles food. Although hepatitis A is seldom serious, in one percent of the cases it can cause severe liver failure and death. It does not cause chronic hepatitis and will not lead to cirrhosis or other long-term liver problems. Hepatitis B, formerly known as serum hepatitis, is found in blood and other body fluids such as urine, tears, semen, breast milk, and vaginal secretions. It is usually transmitted in blood, via transfusions, or through illicit injectable-drug use. But it also can be contracted through a minor cut or abrasion, or during such everyday acts as toothbrushing, kissing, or having sex. Infants can contract the disease from the mother at birth, or from the mother's breast milk. Dental work, ear piercing, and tattooing are other ways people can get hepatitis B. Type C hepatitis virus is the cause of a disease known as "non-A, non-B hepatitis," which is also contracted through contact with contaminated blood, or through household or sexual contact with an infected person. It affects approximately 170,000 Americans each year. Viral hepatitis may produce no symptoms at all. When they occur in type A, they usually begin suddenly and last for several weeks. This period is followed by a convalescent phase of anywhere from two to 12 weeks. Symptoms of viral hepatitis mimic the flu and include mild fever, fatigue, nausea, muscle and joint aches, loss of appetite, vomiting, occasional diarrhea, and vague abdominal pain. Some people also develop a yellow cast to the skin and whites of the eyes known as jaundice, along with dark-colored urine, clay-colored stools, and itching of the skin. The liver may be enlarged and tender. Patients usually recover completely from hepatitis A and develop a lifelong immunity to it. Immune globulin (IG) should be administered to anyone exposed to type A hepatitis as soon as possible or within two weeks after jaundice appears. This medication is 80 to 90 percent effective in preventing the disease. A vaccine for hepatitis A is now available. Hepatitis B also frequently has no symptoms; but if they do occur, they are similar to those of hepatitis A. The disease follows an unpredictable course, sometimes incapacitating a person for weeks or months and leading to complications, but usually ending in full recovery. Hepatitis C is similar to hepatitis B, but milder. However, like hepatitis B, it may develop into a chronic form in approximately 30 to 50 percent of those who contract it. The problem with hepatitis B is that five to 10 percent of those who become infected with this disease become chronic carriers who can spread it to others for an indefinite period of time. At present there are more than a million of these silent carriers in this country, and their number is growing by two to three percent annually. Consequently, authorities recommend that all children and anyone with a high risk of exposure be vaccinated against this dangerous virus. Chronic carriers usually do not develop chronic hepatitis. If it does develop, however, cirrhosis and primary cancer of the liver can be long-term consequences. An estimated 4,000 people in the United States die from hepatitis B-related cirrhosis annually. Carriers are many times more likely to get liver cancer than are non-carriers. Treatment for acute hepatitis consists of rest and small, nourishing meals; fluids; and sometimes anti-nausea drugs such as trimethobenzamide (Tigan). Chronic cases of hepatitis B and C are now being treated with interferon, a biotech medicine derived from the human immune system. | THE GALLBLADDER | | The gallbladder stores bile, a substance the liver produces to aid digestion. The most common disorder of the gallbladder is the formation of gallstones. These stones often get stuck in the bile ducts that lead from the gallbladder to the first part of the small intestine, causing the gallbladder to become inflamed. Gallbladder surgery, in which the entire organ is removed, is one of the most common operations in this country. Laparoscopic cholecystectomy, a new procedure that requires only a small incision, has cut down stress and recovery time dramatically. Chenodiol, a recently available drug that dissolves gallstones, is an alternative to surgery. However, due to limited success and troublesome side effects, it is not widely used. |
Other Diseases of the Liver
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In cirrhosis, liver cells are damaged and replaced by scar tissue which, as it accumulates, hardens the liver, diminishes blood flow, and causes even more cells to die. The loss of liver function that accompanies this degenerative condition results in gastrointestinal disturbances, jaundice, enlargement of the liver and spleen, emaciation, and accumulation of fluid in the abdomen and other tissues. Over half of the deaths related to cirrhosis are due to alcohol abuse, hepatitis, and other viruses. Chemicals, poisons, too much iron or copper, and blockages of the bile duct also may cause the disease. Treatment of cirrhosis usually consists of eliminating the underlying cause, if possible, to avoid further damage, and preventing or treating complications. Care is mostly supportive, often including a specialized diet, diuretics (water pills), vitamins, and abstinence from alcohol. For some patients, a liver transplant is now a feasible option. Liver abscesses are caused by bacteria, such as Escherichia coli (E. coli) or staphylococcus (staph), or by Entamoeba histolytica, the parasite that causes amebic dysentery. In either case, the offending organisms destroy liver tissue, leaving a cavity that fills with other infectious organisms, white blood cells, and liquefied liver cells. Common symptoms include shoulder and abdominal pain, fever, weight loss, chills, nausea, vomiting, anemia, and, if there is severe liver damage, jaundice. If the offending organism can't be determined, liver abscesses are treated with long-term antibiotics such as aminoglycosides, cephalosporins, clindamycin, or chloramphenicol. If E. coli is causing the infection, treatment includes ampicillin; for Entamoeba histolytica, chloroquine (Aralen), or metronidazole (Flagyl) are included. Pediatric liver diseases afflict tens of thousands of children in this country annually, and kill hundreds each year. More than 100 different liver diseases are found in infants and children. Most of these disorders are genetic. Among the more common are: - Biliary atresia, an inadequate bile duct, often fatal but sometimes relieved by surgery;
- Chronic active hepatitis, in which scar tissue forms and destroys the liver;
- Wilson's disease, in which an abnormally large buildup of copper in the liver is treated with vitamin B6 and d-penicillamine, or, in some cases, corticosteroids such as prednisone;
- Reye's syndrome, an acute, often fatal disease secondary to flu or other infections in which fat accumulates in the liver and the patient lapses into coma.
Other serious diseases of the liver, fortunately seen less frequently than these discussed above, include fatty liver, hepatic coma, and liver cancer. |
