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The diagnosis of HCV is based
on clinical signs and symptoms, blood tests and a liver biopsy.
Acute HCV is diagnosed by clinical presenting symptoms such
as jaundice (yellow color of the eyes and skin), nausea, and
flu-like symptoms. Hepatitis C is also diagnosed by laboratory
or blood tests.
The blood tests for HCV are
based on AST, anti-HCV by enzyme-linked immunosorbent assay
(EIA) and HCV polymerase chain reaction (PCR) assay. A 10-fold
increase in serum ALT and the presence of anti-HCV is also
a sign of hepatitis. HCV is also detected by the presence
of serum (blood without red and white cells) anti-HCV antibodies
by a third-generation EIA test. As with all EIA there are
a small percentage of false-positive results. Additional testing
is useful for confirmatory diagnosis of the EIA. The gold
standard to confirm the diagnosis of HCV is to test for HCV
RNA (hepatitis C virus ribonucleic acid) using a sensitive
PCR assay. The detection of HCV RNA in the serum indicates
an active infection. This test is especially useful in patients
who are HIV positive. Testing for anti-HCV may be negative
despite having HCV infection because they may not produce
enough antibodies for detection by EIA. Also, diagnosis of
acute disease is difficult because anti-HCV is not always
present when the patient presents to the healthcare provider
with symptoms. Anti-HCV is not detected until 2 to 8 weeks
after onset of symptoms in approximately 30 to 40 percent
of patients. Although HCV RNA, a more expensive test, can
readily detect acute HCV, an alternate approach would be to
repeat the anti-HCV test one month after the onset of symptoms.
Chronic HCV is diagnosed when anti-HCV is present and serum
ALT levels remain high or elevated for more than 6 months.
There are several methods
for measuring the amount or “titer” of HCV in the serum. These
methods include a quantitative PCR and a branched DNA (bDNA)
test. The viral load of HCV may not correlate with the severity
of the hepatitis or with a poor prognosis (as it does with
HIV); but viral load does correlate with the likelihood of
a response to antiviral therapy. Low viral loads (less than
2 million) respond better to current antiviral therapy.
A genotype (the hereditary
information present in the virus) is helpful in making recommendations
and counseling regarding therapy. Once the genotype is tested
it does not need to be tested again since it will not change.
Patients with genoypes 2 and 3 are almost three times more
likely to respond to therapy. Furthermore, genotype 1 may
require a more lengthy treatment.
Liver biopsy is not necessary
for diagnosis, but is useful for grading the severity of disease
and staging the degree of fibrosis (scarring) and permanent
damage to the liver such as the Histologic Activity Index
(HAI). Most clinicians use a more qualitative approach to
classify by stage: 0 = no fibrosis, 1 = mild fibrosis, 2 =
moderate fibrosis, 3 = severe fibrosis, including bridging
fibrosis, and 4 = cirrhosis.
Before treatment of hepatitis
C with drug therapy can be started, the patient needs to have
a thorough examination in order to identify potential co-existing
health problems that may not be compatible with HCV therapy.
A few of the contraindicated illnesses are major depression,
heart problems, and kidney disease. Drug and alcohol use must
also be controlled before therapy starts. Other factors that
should be taken into consideration for treatment are viral
load, age, and results of the liver biopsy. The risks and/or
benefits of therapy must be assessed on an individual basis.
All patients with chronic
HCV infection are considered potential candidates for antiviral
therapy. However, after evaluation, treatment is clearly only
recommended for a select group of patients. The current treatment
of choice is a combination therapy including interferon and
ribavirin. Treatment is highly recommended in patients who
are at greatest risk for cirrhosis. Patients over 60 years
and children need to be evaluated and reassessed at regular
periods as benefits of treatment have not been well supported
in the research.
Antiviral therapy for HCV
includes interferon (IFN) or pegylated interferon (PEG-IFN)
or more commonly a combination therapy with IFN or PEG-IFN
and ribavirin. Although interferon is produced naturally in
the body to fight viruses, a synthetic or made-in-the-laboratory
alpha interferon is used for medical treatments. Alpha interferon
(alfa-2a, alfa-2b) is usually given at a dose of 3 million
units (MU) subcutaneous (in the fat) injection three times
a week or interferon alacon-1 is given 9 micrograms (mcg)
3 times a week for 24 weeks. Oral ribavirin is given twice
daily in the form of a 200 mg capsule. The new pegylated interferon
(PEG-IFN) was developed to avoid the peaks and troughs (low
dips) of interferon levels by remaining in the blood for a
longer period of time, having the advantage of lasting longer
and only administered once per week. PEG-INF alpha is given
based on the weight of the patient. PEG-IFN alfa combined
with ribavirin is now replacing the old IFN-alpha combined
with ribavirin as the standard or “gold standard” treatment
for chronic HCV infection.
Treatment with interferon
alone or combination therapy with interferon and ribavirin
leads to rapid improvements in serum ALT levels in 50–75%
of patients and the disappearance of detectable HCV RNA from
the serum in 30–50%. A response is considered “sustained”
if HCV RNA remains undetectable for 6 months or more after
therapy stops. Combination therapy with interferon and ribavirin
leads to loss of HCV RNA on treatment in 50–55% of patients
and a sustained loss in 35–45%. Optimal duration of therapy
varies depending on whether interferon monotherapy or combination
therapy is used, as well as by HCV genotype. Patients with
genotypes 2 and 3 have a high rate of response to combination
treatment (60–70%), and a 24-week course of combination therapy
yields results equivalent to those of a 48-week course. In
contrast, patients with genotype 1 have a lower rate of response
to combination therapy (25–35%), and a 48-week course yields
a significantly better sustained response rate.
In HIV/HCV co-infection,
benefits of therapy for HCV must take into consideration the
concurrent use of anti-HIV medications and medical conditions.
If CD4+ counts are normal or minimally abnormal (greater than
400), responses are similar to those in patients who are not
infected with HIV. Ribavirin may still have significant drug
interactions with other antiretroviral drugs.
Treatment of HCV infection
with the current gold standard is not always effective and
treatments regimens can be difficult for a patient to tolerate.
Before starting on antiviral therapy you should receive counseling
on the potential side effects and how they will affect your
ability to function at work and in the activities of daily
living.
The major potential side
effects of interferon include depression, irritability, anxiety,
impaired concentration, insomnia, autoimmune disease and bone
marrow compromise. Also, in addition to these symptoms, the
most common side effects of interferon include flu-like symptoms:
fatigue, muscle aches, headaches, nausea, vomiting, rigors
(shakes), and a low-grade fever. The loss of hair (alopecia)
can occur in women.
The major side effect of
ribavirin is hemolytic (breakdown of red blood cells) anemia.
In some cases, anemia is so severe that therapy must be discontinued.
Ribavirin has also caused birth defects during animal studies.
Both ribavirin and combination therapy should not be used
on women who are pregnant or who may become pregnant, or on
their male partners, during therapy or six months after therapy
is completed. Women of childbearing potential must use two
forms of effective contraception (birth control) due to the
possibility of serious birth defects.
If there is no response to
current therapies, some patients may be considered for controlled
clinical trials. When the liver decompensates and fails, liver
transplantation remains the only other option for treatment
of hepatitis C at this time. However, the donor liver often
becomes reinfected with the virus. Liver transplantation is
still rather controversial among patients co-infected with
HIV and HCV.
Since the liver is already
being damaged from HCV, steps must be taken to protect it
from further harm. Consultation with the healthcare provider
about the use of any medication, including over-the-counter
and herbal supplements, must be included. Alcoholic beverages
should be stopped. Every effort should be made to stop smoking.
Diet control and avoidance of obesity appear to be helpful
in the care of the liver. All patients with HCV, if not previously
exposed to hepatitis A and B, should be vaccinated. Amble
rest and a healthy lifestyle will help strengthen the immune
system. Regular medical attention is important and new problems
should be identified immediately. Hepatitis C support groups
are available to provide encouragement to those experiencing
problems and challenges living with this disease.
Bethsheba Johnson is an
APRN. She is affilated with BC Luck Care Center and Midwest
AIDS Training and Education Center (MATEC) of Chicago.
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