a special program of the National Emergency Medicine Association (NEMA)
Transcripts: 539-3 and 539-4
Week: 539.3 Guest: Dr. Bruce Bacon, Prof. Internal Medicine, St. Louis Univ. School of Medicine Topic: Hepatitis C, Part One of Two Producer/Host: Steve Girard
NEMA: The fight against viral infections can be likened to a heavyweight title bout....researchers and physicians land some big blows, but it's very hard to figure out how to score a knockout...because the virus seems to change every round, and the tactics have to change in order to keep the virus reeling. We're talking about Hepatitis C today with Dr. Bruce Bacon, a Professor of Internal Medicine at St. Louis University Medical School and head of its Gastroenterology and Hematology Department...
BACON: The key thing to know about Hepatitis C is, first that it is a virus that is relatively new...We have only had testing available for hepatitis C virus since 1990. Prior to that time we knew that there was a virus that caused liver disease and it was called non-A, non-B hepatitis and that's because we had tests available for hepatitis A and for hepatitis B, and they would be negative in these individuals and so we called it non-A, non-B...and then when we found out that, we had testing available what was subsequently called the C virus, we gave it that new name. The other thing that's very important relative to hepatitis C is, also in 1990, a treatment became available for viral hepatitis, and that was the use of alpha-interferon. And so there's been an explosion of information about hepatitis C and its treatment over these last five to six years.
NEMA: Give me a range of problems that hepatitis causes, in general, and in particular, the effects of hepatitis C produces....
BACON: I think that's an important question...you've heard of hepatitis A and hepatitis B before. Hepatitis A is always an acute infection, and it never causes a chronic, long term problem. And, everybody gets over the acute infection...they may have just some flu symptoms, but in general, it's an acute illness that lasts several weeks to several months. Hepatitis B and hepatitis C can both cause chronic hepatitis. What we as liver specialists mean by chronic hepatitis is that liver enzymes are still abnormal, blood tests of liver function are still abnormal six months after the acute infection. And there are characteristic changes on a liver biopsy sample. Now, the main difference between hepatitis B and hepatitis C, relative to chronic hepatitis is that only about five percent of patients with hepatitis B develop chronic hepatitis, whereas about 90% of patients who are exposed to hepatitis C will develop chronic hepatitis. Then, within that group of people, anywhere from 30 to 50% of those people can go on and develop cirrhosis of the liver...that's where there's scar tissue that forms in the liver and a variety of complications that can occur from cirrhosis.
NEMA: Dr. Bacon says one step down the line, some of the patients with hepatitis C can develop liver cancer after a long term infection. We'll investigate where the virus comes from, how we transmit it, and what makes it different, and more dangerous than other hepatitis strains. I'm Steve Girard.
Week: 539.4 Guest: Dr. Bruce Bacon, Prof. Internal Medicine, St. Louis Univ. School of Medicine Topic: Hepatitis C, Part Two of Two Producer/Host: Steve Girard
NEMA: We've been talking with Dr. Bruce Bacon, a professor and liver specialist at St. Louis University Medical School about hepatitis C...a persistent and more dangerous form of hepatitis...in which about 90% of those exposed get chronic hepatitis...with possible long term effects on the liver. How do we get hepatitis C...where does it come from and how do we transmit it from one person to another?
BACON: If you look at studies of patients who have hepatitis C, and find out where they think they got it from, about ten percent have evidence of a prior blood transfusion, and we know that prior to 1990, when testing became available for hepatitis C, that about 7% of people who received blood transfusions got hepatitis C from that blood. Then, about 40% of people have a history of having shared needles with previous IV drug abuse. There's about five percent of people who are health care workers...doctors, nurses, lab technicians...who've had needle sticks or exposure to blood products that way. That leaves you with about 35 or 40 % of people where we don't know exactly where they got it from.
NEMA: What's different about the hepatitis C virus that doesn't allow our bodies to eliminate it?
BACON: We do develop antibodies to hepatitis C and that allows us to detect whether or not someone has been exposed to hepatitis C, but they're not the same kind of anti-bodies like you get in hepatitis A and hepatitis B, which are anti-bodies that can actually clear the virus. There's something about the hepatitis C virus that prevents that from happening. It escapes the wrath of the immune system, to eliminate the virus, and part of that because it will change.
NEMA: What about prognosis and treatment for those who contract hepatitis C?
BACON: If exposed to hepatitis C, about 90% of people can develop chronic hepatitis...of those, anywhere from 30 to 50% will develop cirrhosis. You have to remember, when you hear that statistic, you have to do the flip side of it, that means 50 to 70% won't develop cirrhosis, and they go on their entire life with this mild, smoldering, chronic hepatitis that never really causes any long term problems. The problem is, we as physicians don't know, you know, if you come in with chronic hepatitis and you're young or middle-aged, we don't know if you're someone who's going to develop cirrhosis over the next 20 years, or if you're someone who just has this mild, smoldering infection. I usually take the approach of trying to treat patients, because there is a treatment available, and it does work to eradicate the virus, in about 10 % of patients.
NEMA: Are there limitations a person has when affected by hepatitis?
BACON: Hepatitis C is the single most common indication for liver transplantation in the United States. Hepatitis C is a really common problem...it's estimated in the United States that about one point four to one point five percent of the population is infected with hepatitis C....that translates into about three and a half million people.
NEMA: Dr. Bruce Bacon says the many people find out they have hepatitis C after they complain of fatigue and a blood work up finds their liver enzyme count is abnormal...and many find out when they donate blood, and are told by the Red Cross they are infected. For more information, contact the American Liver Foundation at 800-223-0179. I'm Steve Girard.