Hepatitis C Infection May Not Always Lead to Chronic Liver Disease
Jan. 19, 2000 (Baltimore) -- Hepatitis C, one type of virus known to infect the liver, may progress to chronic liver disease less frequently than has been thought, according to a study published in the Jan. 18 issue of the Annals of Internal Medicine.
"We have known for some time that not everyone who is infected with hepatitis C [HCV] will go on to develop more severe disease. This study supports findings from other studies we have done showing that HCV infection and chronic liver disease are related, but chronic liver disease does not necessarily follow HCV infection," says lead author Leonard Seeff, MD, senior scientist for hepatitis C at the National Institute for Diabetes and Digestive and Kidney Diseases at the National Institutes of Health, in an interview with WebMD.
Seeff and colleagues analyzed blood taken from military recruits between 1948 and 1954 and stored frozen until recently. The blood was tested for HCV, and the results were correlated with the presence of liver disease in the subjects. A very low rate of infection was found, and only one of those people who were infected developed liver disease.
"I think one of the important findings of this study is it shows that HCV has been around much longer than many of us suspected," says Seeff. "I think it also shows that if we look at HCV infection at its onset in a group of young, healthy people, a much different picture emerges than that found when we examine a group of people with HCV infection and chronic liver disease. This long-term perspective is essential if we're going to understand the natural history of the disease."
The investigators' findings are quite different from observations in other populations, especially in Japan, where high rates of HCV infection, chronic liver disease, and cancer are seen. "I think there must be another factor involved in the development of chronic disease besides simply HCV infection," Seeff says.
"While we may not be able to say that HCV infection inevitably leads to liver disease, we do know that the number of cases of chronic liver disease related to the infection in this country is expected to increase dramatically," says Alan Brownstein, president and CEO of the American Liver Foundation, in an interview with WebMD. "About [2%] of the U.S. population is HCV-positive, the majority of whom are 35-50 years of age. As this group ages, much more liver disease will become apparent. We'd like to see physicians encourage people to get tested for HCV since most people don't even know they have it. Then the physician and the patient can decide to do things like avoid alcohol and get immunized against hepatitis A and B, so chronic disease can be avoided if possible."