What are
the consequences of hepatitis C infection for the health of the liver? What are
the symptoms of liver disease in hepatitis C infection?
Stage 1 –
Acute hepatitis: The period
of the first six months after infection is called acute hepatitis C infection.
During this time the immune system battles intensively with the virus. In 20 to
50% of cases this can lead to a spontaneous clearance of the virus. Symptoms
(e.g. exhaustion, mild nausea, occasionally also a yellowing of the skin and
eyes) may become noticeable six to nine weeks after exposure – however, this is
not the case for everyone. Hepatitis C can also progress without any symptoms.
If the acute infection is detected promptly and treated the chances of cure are
very good, at around 90%.1Meanwhile, similar cure rates are
also achieved in chronic hepatitis C with new antiviral treatments. Studies are
ongoing to establish their role in the treatment of acute hepatitis C.
Stage 2 –
Chronic hepatitis: For 50 to
80% of people who are have hepatitis C infection, the immune system alone
cannot eliminate the virus within six months. The liver inflammation (hepatitis)
then becomes chronic.
Glossary
- acute infection
In
hepatitis, the first six months of infection. See also ‘chronic infection’.
- cirrhosis
Scarring of the liver – the structure of the liver is altered. See also
‘fibrosis’, which is moderate scarring. See also ‘compensated cirrhosis’ and
‘decompensated cirrhosis’.
- decompensated cirrhosis
The later stage of
cirrhosis, during which the liver cannot perform some vital functions and
complications occur. See also ‘cirrhosis’ and ‘compensated cirrhosis’.
- fibrosis
Scarring of the liver
– the development of hard, fibrous tissue. See also ‘cirrhosis’, which is more
severe scarring.
- genotype
A strain or subtype of a virus. For hepatitis C, genotypes are identified by a number (e.g. genotypes 1,2,3,4,5 and 6); some subtypes have also been identified (e.g. genotypes 1a and 1b). For hepatitis B, genotypes are identified by a letter (A to H). The genotype may influence the risk of disease progression for both viruses; some genotypes respond differently to some treatments.
- rate
The number of events that we would expect to occur during a specified period of follow-up (e.g. 100 person-years). Particularly useful when follow-up periods vary from person to person in a study, or where a person may experience more than one event.
- RNA
Ribonucleic acid, the
form in which a virus stores its genetic material.In hepatitis C, RNA (viral load) testing is used for diagnosis, to
help predict treatment outcome and to monitor response to treatment.
- spontaneous clearance
When, during acute viral hepatitis infection, the immune system responds effectively to the virus and eliminates it from the body, without medicines. This is a cure.
- stage
The stage of hepatitis infection refers to the amount of liver scarring
(fibrosis) detected by biopsy. Usually measured on scales of 0 to 4, or 0 to 6
(higher numbers indicated more severe inflammation).
Stage 3 –
Fibrosis: Untreated
chronic hepatitis can lead to a scarring of the liver over years or decades. At
first the destroyed liver cells can be replaced by new liver cells, but later
in the course of the disease the gaps created by the destruction of liver cells
are closed up by connective tissue cells, which have no function (scar tissue).
This increasing scarring of the liver is called fibrosis. Fibrosis is a
precursor of cirrhosis.
Stage 4 –
Cirrhosis of the liver: When the scarring is so far advanced that it causes structural changes
with nodular alterations, this is called cirrhosis of the liver. See Cirrhosis for further information.
If
hepatitis C remains untreated, up to 40% of people develop cirrhosis within 30
years.1 The rate of progression of liver
damage appears to be affected by a number of factors, including hepatitis C
genotype, alcohol intake, smoking, older age, body weight, co-morbidities and
gender. A large French study found that the average time to the development of
fibrosis among men infected after the age of 40 was 13 years, while women who
were infected before the age of 40 and did not drink alcohol took an average of
42 years to progress to fibrosis.2
Liver
disease progression is more likely, and occurs more rapidly, in people with
HIV/HCV-co-infection (see HIV and hepatitis C co-infection for further information).
Stage 5 –
Liver cancer: Liver
cancer is a possible consequence of chronic liver diseases and may also occur
in hepatitis C patients, mostly due to the development of cirrhosis. Liver
cancer is one of the most difficult types of cancer to treat and on the whole
it does not have a good prognosis. The likelihood of dying within the first
year of the diagnosis is 33%.3 A cure through surgery,
radiofrequency ablation or transplantation is possible in a minority of people.
Other procedures, such as chemoembolisation or using medication, such as
sorafenib, may prolong survival.