Author: John C. Martin
Author Date: 1/17/2003
Of the 170 million people around the world with chronic hepatitis C
(HCV) infection(1), medical science has determined through years of
research that a certain percentage has no symptoms, even though the
virus is present in their system. But relatively little is known
about how common liver damage may be in asymptomatic HCV patients.

Before it became possible to test donated blood for the presence of
HCV, many people became infected through blood transfusions. Other
ways to spread hepatitis C include sharing infected syringes among
illicit drug users, exposure to blood in the workplace (healthcare
workers, firefighters and police officers), and procedures like
tattooing, body piercing, or the use of dentistry tools that have
not been sterilized.

Mysteries of HCV

Yet, the source of infection is unknown in many people. Although
some people with HCV infection become severely ill to the point in
which they may need a liver transplant, many remain healthy and have
no symptoms. In people who are infected and asymptomatic, it is not
clear how many of those also have liver damage. Knowing the extent
of this so-called "silent" liver damage will help physicians
determine how aggressive they should be in testing asymptomatic
patients for the possibility of hepatitis C.

So, a group of Italian researchers set out to help clarify the
little information that does exist, publishing the results of their
study late last year.(2)

Doctors at the University of Padova in Italy examined 4,820
apparently healthy Telecom employees, or their relatives, in
northeastern Italy who had been screened for certain cardiovascular
risk factors. The scientists conducted a range of tests in each
individual, including checking for alanine aminotransferase (ALT)
levels, and conducting a test known as an enzyme-linked
immunosorbent assay (EIA).

Effective HCV Testing

EIA tests can detect specific HCV antibodies in infected
individuals. The tests can detect more than 95 percent of
chronically infected patients, but only 50 percent to 70 percent of
acute infections.(2) Tests to determine alanine aminotransferase
levels are also effective in determining whether a person has liver
damage, and in most cases, are less expensive. Alanine
aminotransferase is an enzyme that is normally present in liver and
heart cells. Elevated levels of ALT in the blood can indicate liver
or heart damage, such as in heart attack patients.

In the study, the researchers found that 116 people were positive
for the anti-HCV antibody and an additional 85 individuals showed
presence of the hepatitis C virus, according to the Italian
scientists. They also reported that enzyme levels were elevated in
more than half of the patients. But, 46 percent of those who showed
presence of HCV had normal levels of ALT.

Additionally, liver damage was spotted in 61 percent of those who
had elevated levels of ALT and showed presence of the virus, which
would be expected. But, underscoring the incidence of "silent" liver
damage, the Italian scientists discovered "significant" liver tissue
abnormalities in 19 percent of the patients who showed "persistently
normal" ALT levels.

Based on those results, the researchers concluded that "hepatitis C
is histologically [relating to liver tissue] active and progressive
in up to 40 percent of asymptomatic persons with HCV infection. The
severity of liver disease correlates with abnormal ALT and increases
with age."