L1-TheElisa test may have false posiive and negatives. It is followed by the RIBA which is more accurate and a confirmation test. Elisa is usually used as a screening test because it is less expensive.
L1- ALT is the best way to track virus C.
L1-SGPT an enzyme present in high concentratin in the liver and goes up when liver cells are damaged. The normal range is 0=48 u/l
Well, of course the first test is for positive diagnosis. The basis for diagnosis upon symptoms cannot be relied upon, since many people have no symptoms at all.
The most commonly used laboratory test is an ELISA, This stands for enzyme linked immunosorbant assay.
In this assay recombinant viral proteins form the solid phase of the assay and to this is added the patients sera. If the patient has antibodies against the recombinant viral proteins, then these antibodies link up to the proteins and an indicator system using anti-human,lgG linked to an indicator enzyme reveals this positive finding. See liver biopsy.
Specific information regarding the history of hepatitis C is not yet available. In general, however, chronic hepatitis C appears
to be a slowly progressive disease that may gradually advance over 10-40 years. There is some evidence that the disease may progress faster when acquired in middle age or older.
WHAT IS THE CHANCE OF GIVING THE DISEASE TO OTHERS?
HCV can be transmitted through blood transfusions. However, all blood is now tested for the presence of this virus by the antibody test. Other individuals who may come in contact with infected blood, instruments, or needles, such as I.V. drug users, health care workers or laboratory technicians are also at risk of acquiring hepatitis c as are those who undergo tattooing or body piercing.
The risk for transmitting hepatitis C sexually is unknown. There have been occasional documented cases of people with chronic hepatitis C transmitting the virus to their only, long-term sexual partner. The U.S. Public Health Service says that because of the lack of sufficient informatin those with only one, long-term sexual partner need not change their sexual practices.
The Centers for Disease Control and Prevention(CDC) say there is a slight increased risk of becoming infected with hepatitis C if you have multiple sex partners.
WHAT IS A VIRAL LOAD?
The use of viral load testing in the
management of viral disease is not
unique to Hep C. It is also widely used
now in the management of HIV disease.
WHAT IS THE DIFFERENCE BETWEEN BEING UNDETECTABLE AND NEGATIVE?
That's a good question.
. Being negative means that
there is no virus present, and it's actually
a term rarely used because the truth is
that the virus in reality is undetectable.
we really cannot clearly say that there is
not virus somewhere else in the body,
that doesn't show up in the sample
tested.
A given test has only so
much capability to detect viral particles.
It may be quite good. but it is very
difficult, in fact impossible, to assure
that a test has definitely measured any
possible virus present.
Undetectable is often
used when a person is in remission or has
gone through treatment which was
successful and the virus has been
subdued and is not active.
WHAT IS THE RR ASSOCIATED WITH VIRAL LOAD READINGS?
The rror is actually quite
good. the percentages range in the high
80 and 90. It is a function of the strength
of the test being used and the rigor, or
standards of the lab using the test.
That's part of the
problem in comparing one's viral load to
someone else's. The fact is that if
different labs use different tests or "kits"
as they are sometimes called, then the
way the viral load is reported out may be
different.
Maybe this is a good
time to say that the main point the
microbiologist I spoke with from the lab
this morning stressed was that actually
viral load testing is not the best way to
monitor one's progression of disease
with hep c.
He, and the literature
confirms this, said that actually the best
way to monitor the activity of the virus
in your body is to tract your liver
function test, the ALT.
This is the transaminase
SGPT. it is an enzyme present in high
concentrations in your liver and goes up
when liver cells are damaged.
The normal adult range
of the ALT is from 0-48 U/L. what you
should do is keep a time long, and see
how it changes over time. If it goes up
there may be reason for concern. If it
drops, we celebrate. And if it stays the
same generally, you can be assured that
the virus is basically stable.
AT WHAT POINT OR NUMBER IS A DOCTOR LOOKING FOR IN THE TITER TO KNOW IF YOU RE A RESPONDER OR NONRESPNDER?
It may depend on which
test the doctor is using.
Generally, the B-DNA
test is used to determine whether a
person is a good candidate for
treatment, and if treatment is working. .
It picks up levels over 350,000 particles
per ml. and your doctor would be looking
for changes from your baseline.
The B-DNA test may be
negative, while your PCR (another viral
load test) is positive. that may still be an
indicator that you are a good candidate
for interferon treatment.
Let me say a word about
the PCR. It's the other main viral load test
used, and is the most sensitive test
available.
PCR stands for
polymerase chain reaction ..
A PCR test takes a sample
of the blood and amplifies the nucleic
acid associated with the virus many
millions of times. this is the chain
reaction which is actually a copying
process.
It brings the nucleic acid
up to detectable levels. the process is
consistent and thereby enables us to
assess how much of the original virus is
present.
One other thing to not is
that this test is more sensitive to some
strains or genotypes of HCV than others.
(And we know there are 6 genotypes and
more than 30 subtypes of HCV RNA.)
That's why it's not a good
idea for patients with different
genotypes to compare viral load test
results.
A low viral load means
that the virus is probably not very active,
and therefore there are fewer particles in
your blood for the test to pick up.
numbers are hard to quote because it
really depends on the kind of test the lab
did and what their standards are. you can
get this information from your doctor.
If you are told your viral
load test is high, that's reason for
concern. It means that the virus is active.
Your doctor would probably also do a
series of evaluations of your liver, such as
the ALT, to determine if there was
actually an impact on liver function.
WHAT IS THE SIGNIFICANCE OF QUAL AND QUANT PCR?
Everyone should also
remember that this is a moving target.
Viral loads tend to fluctuate from time to
time.
Qual, or "qualitative"
evaluation is actually usually the first
measure that is done. It is highly sensitive
to the virus, however may have false
positives. A quant, or "quantitative" test
is then done to be more specific and
either confirm a qual positive, or identify
that it may be a false positive.
When a determination is
first being made as to whether someone
is HCV positive, labs take many
precautions and do multiple tests to rule
out any errors that are a function of the
test themselves and not the true status
of the person being tested. One test is
not done.
The ELISA is the test that
is sensitive but may have false positives
and negatives. It is followed by the RIBA
which is more accurate and a
confirmation test.
The ELISA is usually used
as a screening test because it is less
expensive.
And expense is an issue
with these tests. For instance, a viral load
test usually costs about $200. In
consideration of how much information
it yields, compared to say multiple ALT's
over time, it is not generally
recommended for use multiple times.
Unless of course someone is being
evaluated as a candidate for interferon
treatment.
IS THERE ANY SIGNIFCANCE TO RISES AND FALLS IN VIRAL LEVELS.?
Yes, there is significance
to changes in viral levels, however always
remember that there are many factors
involved in assessing these levels.
Obviously one wants their viral load /
level to go down because it means the
virus is under control or in remission. But
also remember that your body is
influenced by many things that may also
influence the virus and cause it to
fluctuate.
Your natural immune
system is your first line of defense and
when it is strong you have the potential
to have an impact on your viral load.
when you first line of defense goes
down,(such as fighting off other seasonal
viruses) then the HCV has a window of
opportunity and may take advantage of
it and replicate faster. That's why it is so
crucial for people with HCV and other
virus to commit to maintaining a strong
natural immune system.
IS IT POSSIBLE TO HAVE A HIGH VIRAL LOAD WITHOUT THE VIRUS BEING ACTIVE?
You may have a high viral
load from previous activity of the virus.
Also, if you have had it for a long time.
That's why some
clinicians don't really use the viral load
test as an indicator of your disease
status. It may be high and stable, or it
may be low and active. what we are
interested in is the health of your liver
ultimately, so other less complex and
expensive test may be better ways to
closely monitor any changes in your
liver's health.
And don't forget, what
genotype of HCV you have may make a
difference.
Let me share an analogy I
saw with people living with HIV disease.
They also use a viral load test to track
their disease status.
The target of the HIV is
the T-Cell, like the HCV invades the liver.
Just as we monitor viral load, we also
keep a careful watch on a person's T-Cell
count. that's really where the damage is
done. a person may have a low viral load,
and still have dropping T-Cells, in which
case there is concern. Likewise there may
be a higher viral load, however no
indication of T-Cell demise.
When some pcr's are done,
the results are back in a week to 10 days
but many take 4-6 weeks. why the
differences?
Here you see local
laboratory differences. It could also be a
function of how many tests are run in
your lab. In smaller communities, the test
may not be done everyday, and
therefore it would take longer. It's really
about the kind of 'Kit" a lab uses and also
the volume of tests they may be running.
Another factor is that
these tests just aren't done in all labs and
sometimes are sent away for processing,
which can add a lot of time to getting
your results.
Regardless of viral load i.e.:
400,000 vs 2 mil, does the viral load
really give any indication on how
aggressive the virus is in your liver?
I wanted to be sure to
mention that one of the limitations of
viral load tests is that they only test for
viral particles found in the blood. and
even if none are detected there
(undetectable) they may still be in other
parts of the body, such as in white blood
cells.
Remember this is only a measure of the
amount of particles in the sample that
was drawn on a specific day and time.
the aggressiveness of the virus in your
liver is not a function of number only. it
involves the genotype of you HCV and
also the strength of your liver, your
general state of health.
WHAT IS THE HISTORY OF HEPC?
Those in close contact with others
should consider being
vaccinated. There is a risk of
contracting hepatitis A through
anal/oral contact. Good hygiene,
washing hands with soap and
water after using the toilet and
good common sense are
essential.
MY DOCTOR SAYS I HAVE A VIRAL LOAD BUT NOT HOW MUCH, WHAT'S A LOW RANGE? WHAT'T A HIGH RANGE?
WHAT IS THE ELISA TEST?
