This year the emphasis is on viral hepatitis. About 400 million people are infected with hepatitis B and another 200 million with hepatitis C. Together these diseases are responsible for the third leading cause of cancer deaths worldwide. Douglas LaBrecque, MD, director of Liver Service at University of Iowa Hospitals and Clinics and co-chair of World Digestive Health Day 2007, talks about viral hepatitis.
What is viral hepatitis?
Hepatitis is an infection that causes damage to liver cells. It can be a short course of disease with minimal symptoms, or it can cause the patient to become jaundiced or turn yellow. In severe cases it can be fulminant and lead to liver failure and death. In certain cases of viral hepatitis, it also may become chronic in a more gradual way and, over the course of many months or years, lead to liver failure or death. There are five primary viruses that we refer to as viral hepatitis and they’re just labeled A, B, C, D, and E.
What is the current state of hepatitis in the United States?
In the United States, the two major problems are hepatitis B and C. There are four to five million chronic carriers of the hepatitis C virus and about half as many for hepatitis B. Hepatitis A is more sporadic and tends to occur in small epidemics related to contaminated food or contaminated water.
How does someone become infected with hepatitis?
As I just mentioned, hepatitis A is primarily transmitted by contaminated food or contaminated water. In contrast, hepatitis B and C are transmitted by exposure to bodily fluid, particularly blood, so that those who are using IV needles, or those who are having unprotected sex, can have hepatitis B or C transmitted in those fashions.
What is hepatitis B? Symptoms?
Hepatitis B, in about half of the cases, will produce very few symptoms and will resolve on its own. However, about five percent of the cases will become chronic carriers and those are the ones that go on to develop liver cirrhosis, liver failure, etc. The symptoms, when they occur, are very general: weakness; fatigue; loss of appetite; often the loss of the taste for cigarettes, if the patient is a smoker; and then the patient may develop very dark urine, cola or tea-colored urine. They may become jaundiced, in which case their skin or their eyes turn yellow.
And what then is the difference with hepatitis C? Symptoms?
Hepatitis C is more of a stealth virus in that the vast majority of patients never develop symptoms. If they do, they are so mild that people don’t pay too much attention to them. In contrast to hepatitis B, however, as many as 80 to 85 percent of those that become infected with hepatitis C go on to become chronic carriers and 20 to 30 percent of them will eventually develop cirrhosis and liver failure.
How does hepatitis lead to cancer?
It does it in several ways. The hepatitis B virus actually becomes incorporated into the genome or the DNA of the liver cell and we believe that that’s part of the way in which it leads to cancer. Both of them produce cirrhosis. Particularly with hepatitis C, liver cancer does not develop until the liver already is so bad scarred (cirrhosis means very severe scarring of the liver). At that point, as the liver keeps trying to repair and regenerate itself, ultimately some abnormal cells develop. With this constant stimulation of damage and repair, damage and repair, those cells begin to take over and form the cancer.
How is hepatitis treated?
One of the exciting things about viral hepatitis for a physician is that in the last 10 to 15 years we’ve developed a wide array of treatment options for both hepatitis B and C. The most common drug use in both is a drug called interferon, which is a natural body substance that fights viral infections, something that we ordinarily produce but inadequately in these infections. That is combined with other drugs like ribavirin, an oral medication. There are a number of additional medications available for the treatment of hepatitis B, which in some cases, are similar to medications used to treat HIV.
Is either hepatitis B or C curable?
Hepatitis C is now considered a curable disease in a little over 50 to 60 percent of patients. Unfortunately, not all patients respond to the treatment. In the case of hepatitis B, we are able to cure only a very small percentage of the patients. However, a very high percentage, well over 70 to 80 percent, can have the disease controlled by oral medications so that it does not progress and cause the complications referred to.
What is it that people can do to prevent hepatitis? Is there a vaccine out there, or what are some of the other things they can look for?
The most important thing with hepatitis B is prevention. The vaccine has been available now for 20-some years. In the United States, since the early to mid-90s, it’s been a required vaccination, beginning at the time of birth. With that, more than 95 percent of all infections can be prevented.
An example, at the head of the Amazon where the indigenous tribes live, is an area where almost 30 percent of the people were chronic carriers of the hepatitis B virus. In 10 years of an intense vaccination program, even in this very difficult region, the carrier rate has been reduced to about three percent. So the vaccine is extremely effective in preventing hepatitis B.
Unfortunately, we don’t have one for hepatitis C and we don’t foresee one in the near future. Prevention of both requires great care in avoiding potential exposure to blood or blood products, since that’s how it’s transmitted. Protected sex as opposed to unprotected sex is very important and the use of sterile needles, the use of sterile syringes, and good infectious disease prevention techniques when everyone is going to be exposed to a needle, even something that sounds simple like a tattoo, is a potential way to transmit the disease if the materials used are not sterile.
If someone wanted to lean more about viral hepatitis, is there a Web site or phone number where they can get more information?
They can call UI Hospitals and Clinics at 319-356-1616 and ask for the Liver Clinic. A second source is the World Gastroenterology Organization www.worldgastroenterology.org which is focusing on viral hepatitis.
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