Chronic Hepatitis C:
Current Disease Management
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Introduction
The hepatitis C virus (HCV) is one of the
most important causes of chronic liver
disease in the United States. It accounts
for about 15 percent of acute viral
hepatitis, 60 to 70 percent of chronic
hepatitis, and up to 50 percent of
cirrhosis, end-stage liver disease, and
liver cancer. Almost 4 million Americans, or
1.8 percent of the U.S. population, have
antibody to HCV (anti-HCV), indicating
ongoing or previous infection with the
virus. Hepatitis C causes an estimated
10,000 to 12,000 deaths annually in the
United States.
A distinct and major characteristic of
hepatitis C is its tendency to cause chronic
liver disease. At least 75 percent of
patients with acute hepatitis C ultimately
develop chronic infection, and most of these
patients have accompanying chronic liver
disease.
Chronic hepatitis C varies greatly in its
course and outcome. At one end of the
spectrum are patients who have no signs or
symptoms of liver disease and completely
normal levels of serum liver enzymes. Liver
biopsy usually shows some degree of chronic
hepatitis, but the degree of injury is
usually mild, and the overall prognosis may
be good. At the other end of the spectrum
are patients with severe hepatitis C who
have symptoms, HCV RNA in serum, and
elevated serum liver enzymes, and who
ultimately develop cirrhosis and end-stage
liver disease. In the middle of the spectrum
are many patients who have few or no
symptoms, mild to moderate elevations in
liver enzymes, and an uncertain prognosis.
Chronic hepatitis C can cause cirrhosis,
liver failure, and liver cancer. Researchers
estimate that at least 20 percent of
patients with chronic hepatitis C develop
cirrhosis, a process that takes at least 10
to 20 years. After 20 to 40 years, a smaller
percentage of patients with chronic disease
develop liver cancer. Liver failure from
chronic hepatitis C is one of the most
common reasons for liver transplants in the
United States. Hepatitis C is the cause of
about half of cases of primary liver cancer
in the developed world. Men, alcoholics,
patients with cirrhosis, people over age 40,
and those infected for 20 to 40 years are
more likely to develop HCV-related liver
cancer.
Risk Factors and Transmission
HCV is spread primarily by contact with
blood and blood products. Blood transfusions
and the use of shared, unsterilized, or
poorly sterilized needles and syringes have
been the main causes of the spread of HCV in
the United States. With the introduction in
1991 of routine blood screening for HCV
antibody and improvements in the test in the
mid-1992, transfusion-related hepatitis C
has virtually disappeared. At present,
injection drug use is the most common risk
factor for contracting the disease. However,
many patients acquire hepatitis C without
any known exposure to blood or to drug use.
The major high-risk groups for hepatitis
C are
- Injection drug users, including
those who used drugs briefly many years
ago.
- People who had blood transfusions
before June 1992, when sensitive tests
for anti-HCV were introduced for blood
screening.
- People who have frequent exposure to
blood products. These include patients
with hemophilia, solid-organ
transplants, chronic renal failure, or
cancer requiring chemotherapy.
- Infants born to HCV-infected
mothers.
- Health care workers who suffer
needle-stick accidents.
Other groups who appear to be at slightly
increased risk for hepatitis C are
- people with high-risk sexual
behavior, multiple partners, and
sexually transmitted diseases
- people who use cocaine, particularly
with intranasal administration, using
shared equipment
Maternal-Infant Transmission
Maternal-infant transmission is not
common. In most studies, only 5 percent of
infants born to infected women become
infected. The disease in newborns is usually
mild and free of symptoms. The risk of
maternal-infant spread rises with the amount
of virus in the mother's blood and with
complications of delivery such as early
rupture of membranes and fetal monitoring.
Breast-feeding has not been linked to spread
of HCV.
Sexual Transmission
Sexual transmission of hepatitis C
between monogamous partners appears to be
uncommon. Surveys of spouses and monogamous
sexual partners of patients with hepatitis C
show that less than 5 percent are infected
with HCV, and many of these have other risk
factors for this infection. Spread of
hepatitis C to a spouse or partner in
stable, monogamous relationships occurs in
less than 1 percent of partners per year.
For these reasons, changes in sexual
practices are not recommended for monogamous
patients. Testing sexual partners for
anti-HCV can help with patient counseling.
People with multiple sex partners should be
advised to follow safe sex practices, which
should protect against hepatitis C as well
as hepatitis B and HIV.
Sporadic Transmission
Sporadic transmission, when the source of
infection is unknown, occurs in about 10
percent of acute hepatitis C cases and in 30
percent of chronic hepatitis C cases. These
cases are usually referred to as sporadic or
community-acquired infections. These
infections may have come from exposure to
the virus from cuts, wounds, or medical
injections or procedures.
Unsafe Injection Practices
In many areas of the world, unsafe
injection practices are an important and
common cause of hepatitis C (and hepatitis B
as well). Use of inadequately sterilized
equipment, lack of disposable needles and
syringes, and inadvertent contamination of
medical infusions are unfortunately
well-documented causes of transmission of
hepatitis C. Careful attention to universal
precautions and injection techniques should
prevent this type of spread. In the United
States, multiple-use vials are a frequent
culprit in leading to nosocomial spread of
hepatitis C.
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The Hepatitis C Virus
HCV is a small (40 to 60
nanometers in diameter),
enveloped, single-stranded
RNA virus of the family
Flaviviridae and genus
hepacivirus. Because the
virus mutates rapidly,
changes in the envelope
proteins may help it evade
the immune system. There are
at least 6 major genotypes
and more than 50 subtypes of
HCV. The different genotypes
have different geographic
distributions. Genotypes 1a
and 1b are the most common
in the United States (about
75 percent of cases).
Genotypes 2 and 3 are
present in only 10 to 20
percent of patients. There
is little difference in the
severity of disease or
outcome of patients infected
with different genotypes.
However, patients with
genotypes 2 and 3 are more
likely to respond to
interferon treatment. |
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Clinical Symptoms and Signs
Many people with chronic hepatitis C have
no symptoms of liver disease. If symptoms
are present, they are usually mild,
nonspecific, and intermittent. They may
include
- fatigue
- mild right-upper-quadrant discomfort
or tenderness ("liver pain")
- nausea
- poor appetite
- muscle and joint pains
Similarly, the physical exam is likely to
be normal or show only mild enlargement of
the liver or tenderness. Some patients have
vascular spiders or palmar erythema.
Clinical Features of Cirrhosis
Once a patient develops cirrhosis or if
the patient has severe disease, symptoms and
signs are more prominent. In addition to
fatigue, the patient may complain of muscle
weakness, poor appetite, nausea, weight
loss, itching, dark urine, fluid retention,
and abdominal swelling.
Physical findings of cirrhosis may
include
- enlarged liver
- enlarged spleen
- jaundice
- muscle wasting
- excoriations
- ascites
- ankle swelling
Extrahepatic Manifestations
Complications that do not involve the
liver develop in 1 to 2 percent of people
with hepatitis C. The most common is
cryoglobulinemia, which is marked by
- skin rashes, such as purpura,
vasculitis, or urticaria
- joint and muscle aches
- kidney disease
- neuropathy
- cryoglobulins, rheumatoid factor,
and low complement levels in serum
Other complications of chronic hepatitis
C are
- glomerulonephritis
- porphyria cutanea tarda
Diseases that are less well documented to
be related to hepatitis C are
- seronegative arthritis
- keratoconjunctivitis sicca
(Sjφgren's syndrome)
- non-Hodgkin's type, B-cell lymphomas
- fibromyalgia
- lichen planus
Serologic Tests
Enzyme Immunoassay
Anti-HCV is detected by enzyme
immunoassay (EIA). The third-generation test
(EIA-3) used today is more sensitive and
specific than previous ones. However, as
with all enzyme immunoassays, false-positive
results are occasionally a problem with the
EIA-3. Additional or confirmatory testing is
often helpful.
The best approach to confirm the
diagnosis of hepatitis C is to test for HCV
RNA using a sensitive assay such as
polymerase chain reaction (PCR) or
transcription mediated amplification (TMA).
The presence of HCV RNA in serum indicates
an active infection.
Testing for HCV RNA is also helpful in
patients in whom EIA tests for anti-HCV are
unreliable. For instance, immunocompromised
patients may test negative for anti-HCV
despite having HCV infection because they
may not produce enough antibodies for
detection with EIA. Likewise, patients with
acute hepatitis may test negative for
anti-HCV when first tested. Antibody is
present in almost all patients by 1 month
after onset of acute illness; thus, patients
with acute hepatitis who initially test
negative may need followup testing. In these
situations, HCV RNA is usually present and
confirms the diagnosis.
Recombinant Immunoblot Assay
Immunoblot assays can be used to confirm
anti-HCV reactivity as well. These tests are
also called "Western blots"; serum is
incubated on nitrocellulose strips on which
four recombinant viral proteins are blotted.
Color changes indicate that antibodies are
adhering to the proteins. An immunoblot is
considered positive if two or more proteins
react and is considered indeterminate if
only one positive band is detected. In some
clinical situations, confirmatory testing by
immunoblotting is helpful, such as for the
person with anti-HCV detected by EIA who
tests negative for HCV RNA. The EIA anti-HCV
reactivity could represent a false-positive
reaction, recovery from hepatitis C, or
continued virus infection with levels of
virus too low to be detected (the last
occurs only rarely when sensitive PCR or TMA
assays are used). If the immunoblot test for
anti-HCV is positive, the patient has most
likely recovered from hepatitis C and has
persistent antibody. If the immunoblot test
is negative, the EIA result was probably a
false positive.
Immunoblot tests are routine in blood
banks when an anti-HCV-positive sample is
found by EIA. Immunoblot assays are highly
specific and valuable in verifying anti-HCV
reactivity. Indeterminate tests require
further followup testing, including attempts
to confirm the specificity by repeat testing
for HCV RNA.
Direct Assays for HCV RNA
PCR and TMA amplification can detect low
levels of HCV RNA in serum. Testing for HCV
RNA is a reliable way of demonstrating that
hepatitis C infection is present and is the
most specific test for infection. Testing
for HCV RNA is particularly useful when
aminotransferases are normal or only
slightly elevated, when anti-HCV is not
present, or when several causes of liver
disease are possible. This method also helps
diagnose hepatitis C in people who are
immunosuppressed, have recently had an organ
transplant, or have chronic renal failure. A
PCR assay has now been approved by the Food
and Drug Administration for general use.
This assay will detect HCV RNA in serum down
to a lower limit of 50 to 100 copies per
milliliter (mL) which is equivalent to 25 to
50 international units (IU). A slightly more
sensitive TMA test is currently under
evaluation and may soon become available.
Almost all patients with chronic hepatitis C
will test positive by these assays.
Quantification of HCV RNA in Serum
Several methods are available for
measuring the concentration or level of
virus in serum, which is an indirect
assessment of viral load. These methods
include a quantitative PCR and a branched
DNA (bDNA) test. Unfortunately, these assays
are not well standardized, and different
methods from different laboratories can
provide different results on the same
specimen. In addition, serum levels of HCV
RNA can vary spontaneously by 3- to 10-fold
over time. Nevertheless, when performed
carefully, quantitative assays provide
important insights into the nature of
hepatitis C. Most patients with chronic
hepatitis C have levels of HCV RNA (viral
load) between 100,000 (105) and 10,000,000
(107) copies per mL. Expressed as IU, these
averages are 50,000 to 5 million IU.
Viral levels as measured by HCV RNA do
not correlate with the severity of the
hepatitis or with a poor prognosis (as in
HIV infection); but viral load does
correlate with the likelihood of a response
to antiviral therapy. Rates of response to a
course of alpha interferon and ribavirin are
higher in patients with low levels of HCV
RNA. There are several definitions of a "low
level" of HCV RNA, but the usual definition
is below 1 million IU (2 million copies) per
mL.
In addition, monitoring HCV RNA levels
during the early phases of treatment may
provide early information on the likelihood
of a response. Yet because of the
shortcomings of the current assays for HCV
RNA level, these tests are not always
reliable guides to therapy.
Genotyping and Serotyping of HCV
There are 6 known genotypes and more than
50 subtypes of hepatitis C. The genotype of
infection is helpful in defining the
epidemiology of hepatitis C. More important,
knowing the genotype or serotype
(genotype-specific antibodies) of HCV is
helpful in making recommendations and
counseling regarding therapy. Patients with
genotypes 2 and 3 are two to three times
more likely to respond to interferon-based
therapy than patients with genotype 1.
Furthermore, when using combination therapy,
the recommended dose and duration of
treatment depend on the genotype. For
patients with genotypes 2 and 3, a 24-week
course of combination treatment using
interferon and 800 milligrams (mg) of
ribavirin daily is adequate, whereas for
patients with genotype 1, a 48-week course
and full dose of ribavirin (1,000 to 1,200
mg daily) is recommended. For these reasons,
testing for HCV genotype is often clinically
helpful. Once the genotype is identified, it
need not be tested again; genotypes do not
change during the course of infection.
Biochemical Indicators of
Hepatitis C Virus Infection
- In chronic hepatitis C,
increases in the alanine and
aspartate aminotransferases
range from 0 to 20 times (but
usually less than 5 times) the
upper limit of normal.
- Alanine aminotransferase
(ALT) levels are usually higher
than aspartate aminotransferase
(AST) levels, but that finding
may be reversed in patients who
have cirrhosis.
- Alkaline phosphatase and
gamma glutamyl transpeptidase
are usually normal. If elevated,
they may indicate cirrhosis.
- Rheumatoid factor and low
platelet and white blood cell
counts are frequent in patients
with severe fibrosis or
cirrhosis, providing clues to
the presence of advanced
disease.
- The enzymes lactate
dehydrogenase and creatine
kinase are usually normal.
- Albumin levels and
prothrombin time are normal
until late-stage disease.
- Iron and ferritin levels may
be slightly elevated.
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Normal Serum ALT Levels
Some patients with chronic hepatitis C
have normal serum alanine aminotransferase
(ALT) levels, even when tested on multiple
occasions. In this and other situations in
which the diagnosis of chronic hepatitis C
may be questioned, the diagnosis should be
confirmed by testing for HCV RNA. The
presence of HCV RNA indicates that the
patient has ongoing viral infection despite
normal ALT levels.
Liver Biopsy
Liver biopsy is not necessary for
diagnosis but is helpful for grading the
severity of disease and staging the degree
of fibrosis and permanent architectural
damage. Hematoxylin and eosin stains and
Masson's trichrome stain are used to grade
the amount of necrosis and inflammation and
to stage the degree of fibrosis. Specific
immunohistochemical stains for HCV have not
been developed for routine use. Liver biopsy
is also helpful in ruling out other causes
of liver disease, such as alcoholic liver
injury or iron overload.
HCV causes the following changes in liver
tissue:
- Necrosis and inflammation around the
portal areas, so-called "piecemeal
necrosis" or "interface hepatitis."
- Necrosis of hepatocytes and focal
inflammation in the liver parenchyma.
- Inflammatory cells in the portal
areas ("portal inflammation").
- Fibrosis, with early stages being
confined to the portal tracts,
intermediate stages being expansion of
the portal tracts and bridging between
portal areas or to the central area, and
late stages being frank cirrhosis
characterized by architectural
disruption of the liver with fibrosis
and regeneration. Several scales are
used to stage fibrosis, most commonly a
scale from 0 to 4 where 0 indicates none
and 4 indicates cirrhosis. Stage 1 and 2
fibrosis is limited to the portal and
periportal areas. Stage 3 fibrosis is
characterized by bridges of fibrosis
bands linking up portal and central
areas.
Grading and staging of hepatitis by
assigning scores for severity are helpful in
managing patients with chronic hepatitis.
The degree of inflammation and necrosis can
be assessed as none, minimal, mild,
moderate, or severe. The degree of fibrosis
can be similarly assessed. Scoring systems
are particularly helpful in clinical studies
on chronic hepatitis.
Serum Markers of Hepatic Fibrosis
Liver biopsy is an invasive procedure
that is expensive and not without
complications. At least 20 percent of
patients have pain requiring medications
after liver biopsy. More uncommon
complications include puncture of another
organ, infection, and bleeding. Significant
bleeding after liver biopsy occurs in 1/100
to 1/1,000 cases, and deaths are reported in
1/5,000 to 1/10,000 cases. Obviously,
noninvasive means of grading and staging
liver disease would be very helpful.
ALT levels, particularly if tested over
an extended period, are reasonably accurate
reflections of disease activity. Thus,
patients with repeatedly normal ALT levels
usually have mild necroinflammatory activity
on liver biopsy. Furthermore, patients who
maintain ALT levels above 5 times the upper
limit of normal usually have marked
necroinflammatory activity. But for the
majority of patients with mild-to-moderate
ALT elevations, the actual level is not very
predictive of liver biopsy findings.
More important is a means to stage liver
disease short of liver biopsy.
Unfortunately, serum tests are not reliable
in predicting fibrosis, particularly earlier
stages (0, 1, and 2). When patients develop
bridging (stage 3) fibrosis and cirrhosis
(stage 4), serum tests may be helpful. The
"danger signals" that suggest the presence
of advanced fibrosis include an aspartate
aminotransferase (AST) that is higher than
ALT (reversal of the ALT/AST ratio), a high
gamma glutamyl transpeptidase or alkaline
phosphatase, a low platelet count (which is
perhaps the earliest change), rheumatoid
factor, elevations in globulins, and, of
course, abnormal bilirubin, albumin or
prothrombin time. Physical findings of a
firm liver, or enlarged spleen or prominent
spider angionata or palmar erythema, are
also danger signals. While none of these
findings are perfect, their presence should
raise the suspicion of significant fibrosis
and lead to evaluation for treatment earlier
rather than later.
Diagnosis
Hepatitis C is most readily diagnosed
when serum aminotransferases are elevated
and anti-HCV is present in serum. The
diagnosis is confirmed by the finding of HCV
RNA in serum.
Acute Hepatitis C
Acute hepatitis C is diagnosed on the
basis of symptoms such as jaundice, fatigue,
and nausea, along with marked increases in
serum ALT (usually greater than 10-fold
elevation), and presence of anti-HCV or de
novo development of anti-HCV.
Diagnosis of acute disease can be
problematic because anti-HCV is not always
present when the patient develops symptoms
and sees the physician. In 30 to 40 percent
of patients, anti-HCV is not detected until
2 to 8 weeks after onset of symptoms. In
this situation, testing for HCV RNA is
helpful, as this marker is present even
before the onset of symptoms and lasts
through the acute illness. Another approach
to diagnosis of acute hepatitis C is to
repeat the anti-HCV testing a month after
onset of illness. Of course, a history of an
acute exposure is also helpful in
establishing the diagnosis.
Chronic Hepatitis C
Chronic hepatitis C is diagnosed when
anti-HCV is present and serum
aminotransferase levels remain elevated for
more than 6 months. Testing for HCV RNA (by
PCR) confirms the diagnosis and documents
that viremia is present; almost all patients
with chronic infection will have the viral
genome detectable in serum by PCR.
Diagnosis is problematic in patients who
cannot produce anti-HCV because they are
immunosuppressed or immunoincompetent. Thus,
HCV RNA testing may be required for patients
who have a solid-organ transplant, are on
dialysis, are taking corticosteroids, or
have agammaglobulinemia. Diagnosis is also
difficult in patients with anti-HCV who have
another form of liver disease that might be
responsible for the liver injury, such as
alcoholism, iron overload, or autoimmunity.
In these situations, the anti-HCV may
represent a false-positive reaction,
previous HCV infection, or mild hepatitis C
occurring on top of another liver condition.
HCV RNA testing in these situations helps
confirm that hepatitis C is contributing to
the liver problem.
Differential Diagnosis
The major conditions that can be confused
clinically with chronic hepatitis C include
- autoimmune hepatitis
- chronic hepatitis B and D
- alcoholic hepatitis
- nonalcoholic steatohepatitis (fatty
liver)
- sclerosing cholangitis
- Wilson's disease
-
alpha-1-antitrypsin-deficiency-related
liver disease
- drug-induced liver disease
Treatment
The therapy for chronic hepatitis C has
evolved steadily since alpha interferon was
first approved for use in this disease more
than 10 years ago. At the present time, the
optimal regimen appears to be a 24- or
48-week course of the combination of
pegylated alpha interferon and ribavirin.
Alpha interferon is a host protein that
is made in response to viral infections and
has natural antiviral activity. Recombinant
forms of alpha interferon have been
produced, and several formulations (alfa-2a,
alfa-2b, consensus interferon) are available
as therapy for hepatitis C. These standard
forms of interferon, however, are now being
replaced by pegylated interferons
(peginterferons). Peginterferon is alpha
interferon that has been modified chemically
by the addition of a large inert molecule of
polyethylene glycol. Pegylation changes the
uptake, distribution, and excretion of
interferon, prolonging its half-life.
Peginterferon can be given once weekly and
provides a constant level of interferon in
the blood, whereas standard interferon must
be given several times weekly and provides
intermittent and fluctuating levels. In
addition, peginterferon is more active than
standard interferon in inhibiting HCV and
yields higher sustained response rates with
similar side effects. Because of its ease of
administration and better efficacy,
peginterferon has been replacing standard
interferon both as monotherapy and as
combination therapy for hepatitis C.
Ribavirin is an oral antiviral agent that
has activity against a broad range of
viruses. By itself, ribavirin has little
effect on HCV, but adding it to interferon
increases the sustained response rate by
two- to threefold. For these reasons,
combination therapy is now recommended for
hepatitis C, and interferon monotherapy is
applied only when there are specific reasons
not to use ribavirin.
Two forms of peginterferon have been
developed and studied in large clinical
trials: peginterferon alfa-2a (Pegasys:
Hoffman La Roche: Nutley, NJ) and
peginterferon alfa-2b (Pegintron:
Schering-Plough Corporation, Kenilworth,
NJ). These two products are roughly
equivalent in efficacy and safety, but have
different dosing regimens. Peginterferon
alfa-2a is given subcutaneously in a fixed
dose of 180 micrograms (mcg) per week.
Peginterferon alfa-2b is given
subcutaneously weekly in a weight-based dose
of 1.5 mcg per kilogram per week (thus in
the range of 75 to 150 mcg per week).
Ribavirin is an oral medication, given
twice a day in 200-mg capsules for a total
daily dose based upon body weight. The
standard dose of ribavirin is 1,000 mg for
patients who weigh less than 75 kilograms
(165 pounds) and 1,200 mg for those who
weigh more than 75 kilograms. In certain
situations, an 800-mg dose (400 mg twice
daily) is recommended (see below).
Combination therapy leads to rapid
improvements in serum ALT levels and
disappearance of detectable HCV RNA in up to
70 percent of patients. However, long-term
improvement in hepatitis C occurs only if
HCV RNA disappears during therapy and stays
undetectable once therapy is stopped. Among
patients who become HCV RNA negative during
treatment, a proportion relapse when therapy
is stopped. The relapse rate is lower in
patients treated with combination therapy
compared with monotherapy. Thus, a 48-week
course of combination therapy using
peginterferon and ribavirin yields a
sustained response rate of approximately 55
percent. A similar course of peginterferon
monotherapy yields a sustained response rate
of only 35 percent. A response is considered
"sustained" if HCV RNA remains undetectable
for 6 months or more after stopping therapy.
The optimal duration of treatment varies
depending on whether interferon monotherapy
or combination therapy is used, as well as
by HCV genotype. For patients treated with
peginterferon monotherapy, a 48-week course
is recommended, regardless of genotype. For
patients treated with combination therapy,
the optimal duration of treatment depends on
viral genotype. Patients with genotypes 2
and 3 have a high rate of response to
combination treatment (70 to 80 percent),
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 (40 to 45 percent), and
a 48-week course yields a significantly
better sustained response rate. Again,
because of the variable responses to
treatment, testing for HCV genotype is
clinically useful when using combination
therapy.
In addition, the optimal dose of
ribavirin appears to vary depending on
genotype. For patients with genotypes 2 or
3, a dose of 800 mg daily appears adequate.
For patients with genotype 1, the full dose
of ribavirin (1,000 or 1,200 mg daily
depending on body weight) appears to be
needed for an optimal response.
Who Should Be Treated?
Patients with anti-HCV, HCV RNA, elevated
serum aminotransferase levels, and evidence
of chronic hepatitis on liver biopsy, and
with no contraindications, should be offered
therapy with the combination of alpha
interferon and ribavirin. The National
Institutes of Health Consensus Development
Conference Panel recommended that therapy
for hepatitis C be limited to those patients
who have histological evidence of
progressive disease. Thus, the panel
recommended that all patients with fibrosis
or moderate to severe degrees of
inflammation and necrosis on liver biopsy
should be treated and that patients with
less severe histological disease be managed
on an individual basis. Patient selection
should not be based on the presence or
absence of symptoms, the mode of
acquisition, the genotype of HCV RNA, or
serum HCV RNA levels.
Patients with cirrhosis found through
liver biopsy can be offered therapy if they
do not have signs of decompensation, such as
ascites, persistent jaundice, wasting,
variceal hemorrhage, or hepatic
encephalopathy. However, interferon and
combination therapy have not been shown to
improve survival or the ultimate outcome in
patients with preexisting cirrhosis.
Patients older than 60 years also should
be managed on an individual basis, since the
benefit of treatment in these patients has
not been well documented and side effects
appear to be worse in older patients.
However, even patients in their late
seventies have been successfully treated for
hepatitis C.
The role of interferon therapy in
children with hepatitis C remains uncertain.
Ribavirin has yet to be evaluated adequately
in children, and pediatric doses and safety
have not been established. Thus, if children
with hepatitis C are treated, monotherapy is
recommended, and ribavirin should not be
used outside of controlled clinical trials.
People with both HCV and HIV infection
should be offered therapy for hepatitis C as
long as there are no contraindications.
Indeed, hepatitis C tends to be more rapidly
progressive in patients with HIV
co-infection, and end-stage liver disease
has become an increasingly common cause of
death in HIV-positive persons. For these
reasons, therapy for hepatitis C should be
recommended even in HIV-infected patients
with early and mild disease. Once HIV
infection becomes advanced, complications of
therapy are more difficult and response
rates are less. The decision to treat people
co-infected with HIV must take into
consideration the concurrent medications and
medical conditions. The efficacy of
peginterferon and ribavirin in HIV-infected
people has been tested in only a small
number of patients. Ribavirin may still have
significant interactions with other
antiretroviral drugs.
In many of these indefinite situations,
the indications for therapy should be
reassessed at regular intervals. In view of
the rapid developments in hepatitis C today,
better therapies may become available within
the next few years, at which point expanded
indications for therapy would be
appropriate.
Patients with acute hepatitis C are a
major challenge to management and therapy.
Because such a high proportion of patients
with acute infection develop chronic
hepatitis C, prevention of chronicity has
become a focus of attention. In small
studies, 83 to 100 percent of persons
treated within 1 to 4 months of onset have
had resolution of the infection. What is
unclear is what dose, duration, and regimen
of treatment to use. A practical regimen is
peginterferon monotherapy for 24 weeks. The
possible role for ribavirin, for short
courses of therapy, and for lower doses of
peginterferon are under evaluation.
In patients with clinically significant
extrahepatic manifestations, such as
cryoglobulinemia and glomerulonephritis,
therapy with alpha interferon can result in
remission of the clinical symptoms and
signs. However, relapse after stopping
therapy is common. In some patients,
long-term or maintenance alpha interferon
therapy can be used despite persistence of
HCV RNA in serum if clinical symptoms and
signs resolve on therapy.
Who Should Not Be Treated?
Therapy is inadvisable outside of
controlled trials for patients who have
- clinically decompensated cirrhosis
because of hepatitis C
- normal aminotransferase levels
- a kidney, liver, heart, or other
solid-organ transplant
- specific contraindications to either
monotherapy or combination therapy
Contraindications to alpha interferon
therapy include severe depression or other
neuropsychiatric syndromes, active substance
or alcohol abuse, autoimmune disease (such
as rheumatoid arthritis, lupus
erythematosus, or psoriasis) that is not
well controlled, bone marrow compromise, and
inability to practice birth control.
Contraindications to ribavirin and thus
combination therapy include marked anemia,
renal dysfunction, and coronary artery or
cerebrovascular disease, and, again,
inability to practice birth control.
Alpha interferon has multiple
neuropsychiatric effects. Prolonged therapy
can cause marked irritability, anxiety,
personality changes, depression, and even
suicide or acute psychosis. Patients
particularly susceptible to these side
effects are those with preexisting serious
psychiatric conditions and patients with
neurological disease.
Strict abstinence from alcohol is
recommended during therapy with interferon.
Interferon therapy can be associated with
relapse in people with a previous history of
drug or alcohol abuse. Therefore, alpha
interferon should be given with caution to a
patient who has only recently stopped
alcohol or substance abuse. Typically a
6-month abstinence is recommended before
starting therapy, but this should be applied
only to patients with a history of alcohol
abuse, not to social drinkers. Patients with
continuing alcohol or substance abuse
problems should only be treated in
collaboration with alcohol or substance
abuse specialists or counselors. Patients
can be successfully treated while on
methadone or in an active substance abuse
program. Indeed, the rigor and regular
monitoring that accompany methadone
treatment provide a structured format for
combination therapy. The dose of methadone
may need to be modified during
interferon-based therapy for hepatitis.
Alpha interferon therapy can induce
autoantibodies, and a 24- to 48-week course
triggers an autoimmune condition in about 2
percent of patients, particularly if they
have an underlying susceptibility to
autoimmunity (high titers of antinuclear or
antithyroid antibodies, for instance).
Exacerbation of a known autoimmune disease
(such as rheumatoid arthritis or psoriasis)
occurs commonly during interferon therapy.
Alpha interferon has bone marrow
suppressive effects. Therefore, patients
with bone marrow compromise or cytopenias,
such as low platelet count (< 75,000
cells/mm3) or neutropenia (<
1,000 cells/mm3) should be
treated cautiously and with frequent
monitoring of cell counts. These side
effects appear to be more common with
peginterferon than standard interferon.
Ribavirin causes red cell hemolysis to a
variable degree in almost all patients.
Therefore, patients with a preexisting
hemolysis or anemia (hemoglobin < 11 grams
[g] or hematocrit < 33 percent) should not
receive ribavirin. similarly, patients who
have significant coronary or cerebral
vascular disease should not receive
ribavirin, as the anemia caused by treatment
can trigger significant ischemia. fatal
myocardial infarctions and strokes have been
reported during combination therapy with
alpha interferon and ribavirin.
Growth factors such as erythropoietin to
raise red blood cell counts or granulocyte
stimulating factor to raise neutrophil
counts have been used successfully to treat
patients with cytopenias during combination
therapy. The proper role, dose, and side
effects of these adjunctive therapies have
yet to be defined.
Ribavirin is excreted largely by the
kidneys. Patients with renal disease can
develop hemolysis that is severe and even
life-threatening. Patients who have
elevations in serum creatinine above 2.0 mg
per deciliter (dL) should not be treated
with ribavirin.
Finally, ribavirin causes birth defects
in animal studies and should not be used in
women or men who are not practicing adequate
means of birth control. Alpha interferon
also should not be used in pregnant women,
as it has direct antigrowth and
antiproliferative effects.
Combination therapy should therefore be
used with caution. Patients should be fully
informed of the potential side effects
before starting therapy.
Side Effects of Treatment
Common side effects of alpha interferon
and peginterferon (occurring in more than 10
percent of patients) include
- fatigue
- muscle aches
- headaches
- nausea and vomiting
- skin irritation at the injection
site
- low-grade fever
- weight loss
- irritability
- depression
- mild bone marrow suppression
- hair loss (reversible)
Most of these side effects are mild to
moderate in severity and can be managed.
They are worse during the first few weeks of
treatment, especially with the first
injection. Thereafter, side effects
diminish. Acetaminophen may be helpful for
the muscle aches and low-grade fever.
Fatigue and depression are occasionally so
troublesome that the dose of interferon
should be decreased or therapy stopped
early. Depression and personality changes
can occur on interferon therapy and be quite
subtle and not readily admitted by the
patient. These side effects need careful
monitoring. Patients with depression may
benefit from antidepressant therapy using
selective serotonin reuptake inhibitors.
Generally, the psychiatric side effects
resolve within 2 to 4 weeks of stopping
combination therapy.
Ribavirin also causes side effects, and
the combination is generally less well
tolerated than interferon monotherapy. The
most common side effects of ribavirin are
- anemia
- fatigue and irritability
- itching
- skin rash
- nasal stuffiness, sinusitis, and
cough
Ribavirin causes a dose-related hemolysis
of red cells; with combination therapy,
hemoglobin usually decreases by 2 to 3 g/dL
and the hematocrit by 5 to 10 percent. The
amount of decrease in hemoglobin is highly
variable. The decrease starts between weeks
1 and 4 of therapy and can be precipitous.
Some patients develop symptoms of anemia,
including fatigue, shortness of breath,
palpitations, and headache.
The sudden drop in hemoglobin can
precipitate angina pectoris in susceptible
people, and fatalities from acute myocardial
infarction and stroke have been reported in
patients receiving combination therapy for
hepatitis C. For these important reasons,
ribavirin should not be used in patients
with preexisting anemia or with significant
coronary or cerebral vascular disease. If
such patients require therapy for hepatitis
C, they should receive alpha interferon
monotherapy.
Ribavirin has also been found to cause
itching and nasal stuffiness. These are
histamine-like side effects; they occur in
10 to 20 percent of patients and are usually
mild to moderate in severity. In some
patients, however, sinusitis, recurrent
bronchitis, or asthma-like symptoms become
prominent. It is important that these
symptoms be recognized as attributable to
ribavirin, because dose modification (by 200
mg per day) or early discontinuation of
treatment may be necessary.
Uncommon side effects of alpha
interferon, peginterferon, and combination
therapy (occurring in less than 2 percent of
patients) include
- autoimmune disease (especially
thyroid disease)
- severe bacterial infections
- marked thrombocytopenia
- marked neutropenia
- seizures
- depression and suicidal ideation or
attempts
- retinopathy (microhemorrhages)
- hearing loss and tinnitus
Rare side effects include acute
congestive heart failure, renal failure,
vision loss, pulmonary fibrosis or
pneumonitis, and sepsis. Deaths have been
reported from acute myocardial infarction,
stroke, suicide, and sepsis.
A unique but rare side effect is
paradoxical worsening of the disease. This
is assumed to be caused by induction of
autoimmune hepatitis, but its cause is
really unknown. Because of this possibility,
aminotransferases should be monitored. If
ALT levels rise to greater than twice the
baseline values, therapy should be stopped
and the patient monitored. Some patients
with this complication have required
corticosteroid therapy to control the
hepatitis.
| Algorithm for Treatment |
| Make the
diagnosis based on
aminotransferase
elevations, anti-HCV
and HCV RNA in
serum, and chronic
hepatitis shown by
liver biopsy. |
|
 |
| Assess for
suitability of
therapy and
contraindications.
Discuss side effects
and possible
treatment outcomes. |
|
 |
|
|
 |
| Genotype 1:
Test for HCV RNA
level immediately
before starting
therapy (baseline
level). |
|
 |
| Genotype 1:
Start therapy with
peginterferon
alfa-2a in a dose of
180 mg weekly or
peginterferon
alfa-2b in a dose of
1.5 mg/kg weekly in
combination with
oral ribavirin in
two divided doses of
1,000 mg daily if
body weight is < 75
kilograms (165 lbs.)
or 1,200 mg daily if
body weight is > 75
kilograms. |
|
 |
| Genotype 2 or
3: Start therapy
with peginterferon
alfa-2a in a dose of
180 mcg weekly or
with alfa-2b in a
dose of 1.5 mcg per
kilogram weekly and
oral ribavirin 800
mg daily in two
divided doses. |
|
 |
| All patients:
At weeks 1, 2, and 4
and then at
intervals of every 4
to 8 weeks
thereafter, assess
side effects,
symptoms, blood
counts, and
aminotransferases. |
|
 |
| Genotype 1:
At week 12, retest
for HCV RNA level.
If HCV RNA is
negative or has
decreased by at
least two log10
units (such as from
2 million IU to
20,000 IU or from
500,000 IU to 5,000
IU or less),
continue therapy for
a full 48 weeks,
monitoring symptoms,
blood counts, and
ALT at 4- to 8-week
intervals. If HCV
RNA has not fallen
by two log10
units, stop therapy. |
|
 |
| Genotype 2 or
3: At 24 weeks,
assess
aminotransferase
levels and HCV RNA
and stop therapy. |
|
 |
| All patients:
After therapy,
assess
aminotransferases at
2- to 6-month
intervals. In
responders, repeat
HCV RNA testing 6
months after
stopping. |
|
|
| Before Starting Therapy |
- Do a liver
biopsy to
confirm the
diagnosis of
HCV, assess the
grade and stage
of disease, and
rule out other
diagnoses. In
situations where
a liver biopsy
is
contraindicated,
such as clotting
disorders,
combination
therapy can be
given without a
pretreatment
liver biopsy.
- Test for
serum HCV RNA to
document that
viremia is
present.
- Test for HCV
genotype (or
serotype) to
help determine
the duration of
therapy and dose
of ribavirin.
- Measure
blood counts and
aminotransferases
to establish a
baseline for
these values.
- Counsel the
patient about
the relative
risks and
benefits of
treatment. Side
effects should
be thoroughly
discussed.
|
|
 |
| During Therapy |
- Measure
blood counts and
aminotransferases
at weeks 1, 2,
and 4 and at 4-
to 8-week
intervals
thereafter.
- Adjust the
dose of
ribavirin
downward (by 200
mg at a time) if
significant
anemia occurs
(hemoglobin less
than 10 g/dL or
hematocrit < 30
percent) and
stop ribavirin
if severe anemia
occurs
(hemoglobin <
8.5 g/dl or
hematocrit < 26
percent).
- Adjust the
dose of
peginterferon
downward if
there are
intolerable side
effects such as
severe fatigue,
depression, or
irritability or
marked decreases
in white blood
cell counts
(absolute
neutrophil count
below 500
cells/mm3)
or platelet
counts (decrease
below 30,000
cells/mm3).
When using
peginterferon
alfa-2a, the
dose can be
reduced from 180
to 135 and then
to 90 mcg per
week. When using
peginterferon
alfa-2b, the
dose can be
reduced from 1.5
to 1.0 and then
to 0.5 mcg per
kilogram per
week.
- In patients
with genotype 1,
measure HCV RNA
level
immediately
before therapy
and again (by
the same method)
at week 12.
Therapy can be
stopped early if
HCV RNA levels
have not
decreased by at
least two log10
units, as
studies have
shown that
genotype 1
patients without
this amount of
decrease in HCV
RNA are unlikely
to have a
sustained
response
(likelihood is <
1 percent). in
situations where
hcv rna levels
are not
obtainable,
repeat testing
for hcv rna by
pcr (or tma)
should be done
at 24 weeks and
therapy stopped
if hcv rna is
still present,
as a sustained
response is
unlikely.
- Reinforce
the need to
practice strict
birth control
during therapy
and for 6 months
thereafter.
- Measure
thyroid-stimulating
hormone levels
every 3 to 6
months during
therapy.
Patients with
genotypes 2 or 3
can stop therapy
at 24 weeks.
Patients with
genotype 1 and a
drop in HCV RNA
by 12 weeks
should continue
therapy for 48
weeks.
- At the end
of therapy, test
HCV RNA by PCR
to assess
whether there is
an
end-of-treatment
response.
|
|
 |
| After Therapy |
- Measure
aminotransferases
every 2 months
for 6 months.
- Six months
after stopping
therapy, test
for HCV RNA by
PCR. If HCV RNA
is still
negative, the
chance for a
long-term "cure"
is excellent;
relapses have
rarely been
reported after
this point.
|
|
|
Options for Patients Who Do Not Respond
to Treatment
Few options exist for patients who either
do not respond to therapy or who respond and
later relapse. Patients who relapse after a
course of interferon monotherapy may respond
to a course of combination therapy,
particularly if they became and remained HCV
RNA negative during the period of
monotherapy. The response rates and optimal
dose (800 vs. 1,000 mg to 1,200 mg of
ribavirin) and duration (24 or 48 weeks) of
peginterferon and ribavirin for relapse or
previous nonresponder patients have not been
defined. The algorithm for treatment given
above is for treatment of naive patients.
An experimental approach to treatment of
non-responders is the use of long-term or
maintenance interferon, which is feasible
only if the peginterferon is well tolerated
and has a clear-cut effect on serum
aminotransferases or liver histology,
despite lack of clearance of HCV RNA. This
approach is now under evaluation in
long-term clinical trials in the United
States. New medications and approaches to
treatment are needed. Most promising for the
future are the use of other cytokines and
the development of newer antivirals, such as
RNA polymerase, helicase, or protease
inhibitors.
Hope Through Research
Basic Research
A major focus of hepatitis C research is
developing a tissue culture system that will
enable researchers to study HCV outside the
human body. Animal models and molecular
approaches to the study of HCV are also
important. Understanding how the virus
replicates and how it injures cells would be
helpful in developing a means of controlling
it and in screening for new drugs that would
block it.
Diagnostic Tests
More sensitive and less expensive assays
for measuring HCV RNA and antigens in the
blood and liver are needed. Although current
tests for anti-HCV are quite sensitive, a
small percentage of patients with hepatitis
C test negative for anti-HCV (false-negative
reaction), and a percentage of patients who
test positive are not infected
(false-positive reaction). Also, there are
patients who have resolved the infection but
still test positive for anti-HCV. Convenient
tests to measure HCV in serum and to detect
HCV antigens in liver tissue would be
helpful. Clinically, noninvasive tests that
would reliably predict liver fibrosis would
be a very valuable advance.
New Treatments
Most critical for the future is the
development of new antiviral agents for
hepatitis C. Most interesting will be
specific inhibitors of HCV-derived enzymes
such as protease, helicase, and polymerase
inhibitors. Drugs that inhibit other steps
in HCV replication may also be helpful in
treating this disease, by blocking
production of HCV antigens from the RNA
(IRES inhibitors), preventing the normal
processing of HCV proteins (inhibitors of
glycosylation), or blocking entry of HCV
into cells (by blocking its receptor). In
addition, nonspecific cytoprotective agents
might be helpful for hepatitis C by blocking
the cell injury caused by the virus
infection. Further, molecular approaches to
treating hepatitis C are worthy of
investigation; these consist of using
ribozymes, which are enzymes that break down
specific viral RNA molecules, and antisense
oligonucleotides, which are small
complementary segments of DNA that bind to
viral RNA and inhibit viral replication. All
of these approaches remain experimental and
few have been applied to humans. The serious
nature and the frequency of hepatitis C in
the population make the search for new
therapies of prime importance.
Prevention
At present, the only means of preventing
new cases of hepatitis C are to screen the
blood supply, encourage health professionals
to take precautions when handling blood and
body fluids, and inform people about
high-risk behaviors. Programs to promote
needle exchange offer some hope of
decreasing the spread of hepatitis C among
injection drug users. Furthermore, all drug
users should receive instruction in safer
injection techniques, simple interventions
that can be life-saving. Vaccines and
immunoglobulin products do not exist for
hepatitis C, and development seems unlikely
in the near future because these products
would require antibodies to all the
genotypes and variants of hepatitis C.
Nevertheless, advances in immunology and
innovative approaches to immunization make
it likely that some form of vaccine for
hepatitis C will eventually be developed.
Selected Review Articles and References
Alter HJ, Seeff LB. Recovery,
persistence, and sequelae in hepatitis C
virus infection: a perspective on long-term
outcome. Seminars in Liver Disease.
2000;20(1):1735.
Centers for Disease Control and
Prevention. Hepatitis A to E. Available at:
www.cdc.gov/ncidod/diseases/hepatitis/slideset/httoc.htm
(accessed Nov. 25, 1996).
Centers for Disease Control and
Prevention. Recommendations for prevention
and control of hepatitis C virus (HVC)
infection and HVC-related chronic disease.
Morbidity and Mortality Weekly Report.
1998;47:139.
Fried MW, Shiffman ML, Reddy KR, et al.
Peginterferon alfa-2a plus ribavirin for
chronic hepatitis C infection. New
England Journal of Medicine.
2002;347:972982.
Lauer GM, Walker BD. Hepatitis C virus
infection. New England Journal of
Medicine. 2001;345:4152.
Liang TJ, Reherman B, Seeff LB, Hoofnagle
JH. Pathogenesis, natural history,
treatment, and prevention of hepatitis C.
Annals of Internal Medicine.
2000;132:296305.
Manns MP, McHutchison JG, Gordon SC,
Rustgi VK, Shiffman M, Reindollar R, Goodman
ZD, Koury K, Ling M, Albrecht JK.
Peginterferon alfa-2b plus ribavirin
compared with interferon alfa-2b plus
ribavirin for initial treatment of chronic
hepatitis C: a randomised trial. Lancet.
2001;358:958965.
McHutchison JG, Gordon SC, Schiff ER,
Shiffman ML, Lee WM, Rustgi VK, Goodman ZD,
Ling M-H, Cort S, Albrecht JK. Interferon
alfa-2b alone or in combination with
ribavirin as initial treatment for chronic
hepatitis C. New England Journal of
Medicine. 1998;339(21):14851492.
Proceedings of the June 1012 "Management
of Hepatitis C: 2002. National Institutes of
Health Consensus Development Conference
Update." Hepatology. 2002;36(5, part
2).
Zeuzem S, Feinman SV, Rasenack J,
Heathcote EJ, Lai M-Y, Gane E, O'Grady J,
Reichen J, Diago M, Lin A, Hoffman J, Brunda
MJ. Peginterferon alfa-2a in patients with
chronic hepatitis C. New England Journal
of Medicine. 2000;343:16661672.
Patient Education Materials
The National Digestive Diseases
Information Clearinghouse (NDDIC) has
patient education materials on hepatitis C.
To obtain free copies, contact the
clearinghouse at
NDDIC
2 Information Way
Bethesda, MD 208923570
Phone: 18008915389
Fax: 7037384929
Email:
nddic@info.niddk.nih.gov
Internet:
http://digestive.niddk.nih.gov
Patient education materials are also
available from
The U.S. Government does not endorse or
favor any specific commercial product or
company. Trade, proprietary, or company
names appearing in this document are used
only because they are considered necessary
in the context of the information provided.
If a product is not mentioned, this does not
mean or imply that the product is
unsatisfactory.
National Digestive Diseases Information
Clearinghouse
2 Information Way
Bethesda, MD 208923570
Email:
nddic@info.niddk.nih.gov
The National Digestive Diseases
Information Clearinghouse (NDDIC) is a
service of the National Institute of
Diabetes and Digestive and Kidney Diseases (NIDDK).
The NIDDK is part of the National Institutes
of Health under the U.S. Department of
Health and Human Services. Established in
1980, the Clearinghouse provides information
about digestive diseases to people with
digestive disorders and to their families,
health care professionals, and the public.
The NDDIC answers inquiries, develops and
distributes publications, and works closely
with professional and patient organizations
and Government agencies to coordinate
resources about digestive diseases.
Publications produced by the
Clearinghouse are carefully reviewed by both
NIDDK scientists and outside experts. This
publication was reviewed by Jay Hoofnagle,
M.D., NIDDK.
This publication is not copyrighted. The
Clearinghouse encourages users of this
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NIH Publication No. 034230
February 2003
|