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Special to ABCNEWS.com
A simple blood test might have
prevented hundreds of thousands of
cases of hepatitis C, a blood-borne
viral infection that often leads to
chronic and fatal liver damage.
In the unfolding story of the
hepatitis C epidemic now affecting
some 4 million Americans, the
failure to use this test is a badly
neglected chapter. And you won’t
find much, if any, medical or media
reference these days to this
saga—namely how the test, available
since the late 1950s, could have
been used early on to screen the
blood supply and reject many donors
infected with hepatitis C.
The public focus on hepatitis
C also includes little mention of
the questionable way this disease
was tracked and managed by doctors,
blood bankers and government health
officials. Research Bedrock The
blood test at issue, known as ALT,
measures the liver enzyme alanine
aminotransferase.
A study back in 1959 showed that
blood donors with raised ALT levels
were three to five times more likely
to transmit hepatitis than those
with normal levels. In those days,
only hepatitis A and B had been
identified. By the mid-1970s,
researchers had developed specific
blood tests to detect each type.
Meanwhile, hepatitis continued to
crop up in about 10 to 15 percent of
blood transfusion recipients.
This form of hepatitis first became
known as non-A and non-B, then was
later dubbed hepatitis C. Once this
new type was identified, it begged
the question of whether blood banks
should routinely use ALT to test for
it, especially since there was no
specific blood test for hepatitis C
like there was for A and B.
Preliminary research evidence back
then supported the idea that ALT
could be of value. By 1981, studies
published in the New England Journal
of Medicine and the Journal of the
American Medical Association had
confirmed that the higher a blood
donor’s ALT score, the greater the
risk that a blood transfusion
recipient would become infected with
hepatitis C.
Some researchers suggested that
screening blood donors with the ALT
test could prevent as many as 40
percent of post-transfusion
hepatitis C infections; the net loss
in units of donated blood would have
been about 3 percent. Between 1981
and 1983, an intense debate raged in
medical journals.
Those opposed to ALT testing,
including blood bankers and
government officials, called for
more studies and planning. They
expressed concern about the
nonspecific nature of the test, the
added costs to the blood banking
system and the loss of donors who
might be falsely detected as
positive for hepatitis C. Some
critics of the test didn’t think
hepatitis C was a serious disease.
Ahead of the Pack
Despite the controversy, several
blood banks began routine ALT
testing in 1982. The New York Blood
Center, for one, figured testing
would add about $2.40 to the cost of
a unit of blood and considered it
worth the expense, given that up to
10,000 New Yorkers would likely be
protected against hepatitis C each
year. Also that year, and then again
in 1984, published cost- benefit
analyses of ALT testing showed
significant benefit from such a
program. By 1986, ALT testing of
donated blood finally became
routine, and another indirect blood
test was also used routinely.
A specific test for hepatitis C has
since been developed and all blood
banks now use it. One estimate is
that one in 10,000 to 100,000 pints
of donated blood may still be
contaminated by the virus, compared
to around one in 100 pints in the
late 1960s.
Exactly how much harm has been
caused by the delay in testing the
blood system for hepatitis C may
never be known. There’s still a lot
to be learned about how the virus
does its damage and how many among
the infected will actually develop
significant diseases such as
cirrhosis, liver cancer or liver
failure. It’s usually estimated that
about 10,000 Americans die each year
from the complications of hepatitis
C infection.
Many don’t even know they’re living
with the virus, however, because it
can be “silent” for decades before
symptoms become obvious. So far,
drug treatments are effective for
only a small number of patients, and
a vaccine is far off.
Federal Heads in the Sand
The federal government recently
launched a campaign to notify
hundreds of thousands of blood
transfusion recipients who may have
been infected. Should we be cynical
about such an effort? Is this a
typical example of what governments
do after they miss an opportunity to
prevent the spread of an illness,
and is the government liable in this
case?
Americans trusted a public health
system that ultimately failed them.
Rather than err on the side of
safety, health officials chose for
years to resist reasonable
scientific evidence in favor of
using the ALT test. They instead
involved themselves in controversies
surrounding the imperfect nature of
the test and its additional cost
when it was clearly the only weapon
available to fight hepatitis C.
Perhaps Congress should investigate
why ALT testing was not implemented
until 1986. A congressional
committee could probe the medical
literature on the subject and read
the well-researched volumes of the
recent Canadian commission on
tainted blood. Committee members
might want to inquire why the Food
and Drug Administration never issued
a formal regulation requiring ALT
testing of donated blood, and how
blood industry representatives who
sat on government health committees
may have influenced decisions about
testing. Better late than
never.
end
Nicholas Regush produces medical
features for ABCNEWS. In the weeks
ahead, he’ll take an inside look at
other trouble spots in medicine,
herald some innovative achievements
and analyze medical trends that will
likely have great impacts on our
lives.
Ann Intern Med 1977 Jul;87(1):14-20
Transmission of non-A, non-B
hepatitis. (Jul 1977) Hoofnagle
JH, Gerety RJ, Tabor E, Feinstone
SM, Barker LF, Purcell RH
In studies conducted in the early
1950s, sera from six asymptomatic
blood donors, implicated in the
transmission of viral hepatitis,
were inoculated into 10 to 20
volunteers each. Five of these
"implicated" donor sera transmitted
clinically apparent hepatitis to the
recipients. The stored serum samples
from these studies have been
reanalyzed using serologic markers
for hepatitis B virus and hepatitis
A virus infection. Two of the donor
sera were hepatitis B surface
antigen (HBsAg)-positive, and both
transmitted hepatitis B virus
infection to all susceptible
recipients, half of whom showing
clinical symptoms. The remaining
three infectious donors were HBs-Ag-negative,
yet were icterogenic to 10% to 47%
of recipients. Testing of serum
samples from these recipients with
hepatitis showed no evidence of
hepatitis B virus or hepatitis A
virus infection. This study and
other recent evidence suggest that
there is a third type of human viral
hepatitis--non-A, non-B
hepatitis--which is due to a
transmissible agent and may well be
associated with a chronic carrier
state.
PMID: 195505, UI: 77220027
------------------
Serum alanine aminotransferase of
donors in relation to the risk of
non-A,non-B hepatitis in recipients:
the transfusion-transmitted viruses
study.
(Apr 1981) AUTHORS: Aach RD;
Szmuness W; Mosley JW; Hollinger FB;
Kahn RA; Stevens CE; Edwards VM;
Werch J SOURCE: N Engl J Med 1981
Apr 23;304(17):989-94
ABSTRACT: To evaluate the incidence
of post-transfusion hepatitis and
factors influencing its occurrence,
the Transfusion-Transmitted Viruses
Study prospectively followed 1513
transfusion recipients from 1974
through 1979. The attack rate for
non-A,non-B hepatitis was 10 per
cent. The incidence of hepatitis was
directly related to the alanine
aminotransferase (ALT) level in
blood donors. In recipients of
multiple transfusions of blood that
had no donor-ALT level above 29 IU
per liter the attack rate was 6 per
cent or less; at higher donor-ALT
levels the attack rate increased
progressively, reaching 45 per cent
in recipients of units with an ALT
of 60 IU or greater. A similar
relation was observed among
recipients of single units of blood.
Moreover, hepatitis developed in 10
of 11 recipients of two units with
an ALT level of 45 IU or greater.
These data indicate that screening
blood for ALT levels would reduce
the incidence of non-A,non-B
post-transfusion hepatitis.
CITATION IDS: PMID: 6782484 UI:
81148757
------------------------
Should donor blood be screened
for elevated alanine
aminotransferase levels? A
cost-effectiveness analysis. (Nov
1984)
JAMA 1984 Nov 23-30;252(20):2839-45
Silverstein MD, Mulley AG, Dienstag
JL
We examined the cost-effectiveness
of alanine aminotransferase (ALT)
screening of donor blood to prevent
non-A, non-B posttransfusion
hepatitis. Based on estimated costs
of ALT screening, blood replacement,
and medical evaluation of donors
with high ALT levels, we concluded
that screening at an ALT level of 45
IU would cost $3.82 per unit. In a
population requiring an average of
3.7 units per transfusion, one case
of hepatitis would be prevented for
every 115 units screened, resulting
in a cost of $439 per case
prevented. With an estimated direct
medical cost of $1,181 per case of
non-A, non-B hepatitis, expected net
savings for each case prevented
would be $742. Screening at other
ALT thresholds would be less
cost-saving. Sensitivity analyses
indicate that screening would be
cost-saving for a wide range of cost
estimates and number of units per
transfusion. Alanine
aminotransferase screening is
warranted until more sensitive and
specific screening tests for
transmissibility of non-A, non-B
hepatitis become available.
LabCorp's National Genetics
Institute Receives FDA Approval for
Nucleic Acid Tests for HCV and HIV-1
BURLINGTON, N.C., Sept. 21 /PRNewswire/
-- Laboratory Corporation of
America(R) Holdings (NYSE: LH) (LabCorp(R))
today announced that its National
Genetics Institute Inc. (NGI) had
its Biologics License Applications
for the UltraQual(TM) HCV RT-PCR and
UltraQual(TM) HIV-1 RT-PCR assays
approved by the U. S. Food and Drug
Administration (FDA). NGI's
UltraQual(TM) assays for HCV and
HIV-1 are the first nucleic acid
amplification tests (NAT) to be
approved by the FDA for donor
screening and will result in earlier
detection of HCV or HIV-1 infection
in plasma donors as well as increase
the overall safety of plasma derived
products. The FDA has also approved
the use of the NGI UltraQual(TM)
HIV-1 RT-PCR assay in combination
with approved pooling algorithms as
an alternative to currently licensed
HIV-1 p24 antigen tests for the
screening of Source Plasma.
When used in combination with FDA
approved pooling and resolution
algorithms, NGI's UltraQual(TM) HCV
RT-PCR and UltraQual(TM) HIV-1
RT-PCR assays are indicated for the
qualitative detection of Hepatitis C
Virus (HCV) and Human
Immunodeficiency Virus, type 1
(HIV-1) nucleic acids in pools of
human Source Plasma comprised of
equal aliquots of not more than 512
individual plasma samples
respectively.
"Our NGI laboratory team has once
again demonstrated outstanding
scientific leadership by becoming
the first clinical laboratory to
have these important assays approved
by the FDA," said Myla P.
Lai-Goldman, M.D., executive vice
president, chief scientific officer
and medical director. "These tests
represent a totally new and
innovative approach to screening
plasma donations. In addition to
enhanced product safety, these
extremely sensitive assays allow us
to test large numbers of donations
in a very efficient manner when used
in combination with complex pooling
algorithms. We look forward to
employing these assays with Alpha
Therapeutic Corporation, which has
simultaneously
received approval by the FDA to
combine its pooling and resolution
algorithms
with LabCorp/NGI's newly approved
assays."
The first national clinical
laboratory to fully embrace genomic
testing, Laboratory Corporation of
America(R) Holdings (LabCorp(R)) has
been a pioneer in commercializing
new diagnostic technologies. As a
national laboratory with annual
revenues of $1.9 billion in 2000 and
over 18,000 employees, the company
offers more than 4,000 clinical
tests ranging from simple blood
analyses to sophisticated molecular
diagnostics. Serving over 200,000
clients nationwide, LabCorp
leverages its expertise in
innovative
clinical testing technology with its
Centers of Excellence. The Center
for Molecular Biology and Pathology,
in Research Triangle Park, North
Carolina, offers state-of-the-art
molecular gene-based testing in
infectious disease, oncology and
genetics. Its National Genetics
Institute in Los Angeles is an
industry leader in developing novel,
highly sensitive polymerase chain
reaction (PCR) methods for testing
hepatitis C and other blood borne
infectious agents. LabCorp's
Minneapolis-based Viro- Med offers
molecular microbial testing using
real time PCR platforms, while its
Center for Esoteric Testing in
Burlington, North Carolina, performs
the largest volume of specialty
testing in the network. LabCorp's
clients include physicians, state
and federal government, managed care
organizations, hospitals, clinics,
pharmaceutical and Fortune 1000
companies, and other clinical
laboratories.
Each of the above forward-looking
statements is subject to change
based on various important factors,
including without limitation,
competitive actions in the
marketplace and adverse actions of
governmental and other third-party
payors. Further information on
potential factors that could affect
LabCorp's financial results is
included in the Company's Form 10-K
for the year ended December 31, 2000
and subsequent SEC filings.
SOURCE Laboratory Corporation of
America Holdings
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