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Hepatitis
C infection and liver disease
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Hepatitis
C infection is a common cause of chronic liver disease in the
community and is a serious public health problem because it is a
major cause of chronic hepatitis, cirrhosis and liver cancer,
and a major indication for liver transplantation worldwide. The
most striking feature of this virus is its ability to induce
persistent infection in at least 855 of infected persons.
The
worldwide prevalence of HCV infection is estimated to be three
percent. The prevalence is higher in persons between the ages of
30 and 50 years than in older or younger age groups, higher in
males than females.
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In
certain countries, health care-related procedures, particularly unsafe
injection practices with reuse of contaminated glass syringes and folk
medicine practices may have played a major role in viral spread.
The
modes of transmission of HCV infection can be divided into
percutaneous like blood transfusion and needlestick inoculation and
nonproteinaceous like sexual contact and perinatal exposure. The risk
posed to the infant from breast-feeding is believed to be negligible.
Acute
infection rare
Acute
infection is rarely seen in clinical practice, because the vast
majority of patients experience no clinical symptoms. Jaundice may
develop in one-fourth of these patients, whereas 10% to 20% may notice
with nonspecific symptoms such as fatigue, nausea, and vomiting
indistinguishable from symptoms of other types of acute viral
hepatitis. Approximately 85% of infected patients do not clear the
virus by six months, and chronic liver disease develops. The most
common complaint of patients with chronic hepatitis C infection is
fatigue.
Other
nonspecific symptoms include depression, nausea, anorexia, abdominal
discomfort, and difficulty with concentration. Once cirrhosis of the
liver develops patients may develop ascites, gastrointestinal
bleeding, alteration in level of consciousness, etc. Jaundice is
rarely seen in chronic HCV infection. Once complications of portal
hypertension or evidence of hepatic synthetic failure develops patient
is referred for liver transplantation.
Serologic
assays are typically used for screening and first-line diagnosis;
virologic assays are needed to confirm active infection or to monitor
the effects of treatment. Detection of viral RNA in serum is used as a
marker of the virus itself. Viral detection is accomplished by
amplification methods such a Polymerase Chain Reaction (PCR), which is
very sensitive and may detect as few as 100 viral copies, usually
within one week of exposure. A pretreatment liver biopsy is mandatory
in patients with chronic Hepatitis C and elevated serum
aminotransferase levels so that correct grading and staging can be
performed. These include:
Persons
who have been treated for clotting problems with a blood product,
persons who were notified that they received blood from a donor who
later tested positive for Hepatitis C, persons who received a blood
transfusion or solid organ transplant,long-term hemodialysis patients,
persons who have signs or symptoms of liver disease (e.g. abnormal
liver enzyme tests), healthcare workers after exposures (e.g. needle
sticks or splashes to the eye) to Hepatitis C positive blood on the
job, children born to Hepatitis C positive women.
The
mean interval between transfusion and chronic hepatitis is nearly 15
years, cirrhosis 20 years, and liver cancer 30 years. Complications
may develop once a patient has cirrhosis. Of every 100 persons
infected with HCV about:
75
to 85 persons may develop long-term infection, 70 persons may develop
chronic liver disease), 15 persons may develop cirrhosis over a period
of 20 to 30 years. Less than three percent of persons may die from the
consequences of long term infection (liver cancer or cirrhosis). The
risk of liver cancer is one percent to four percent per year. Once
cirrhosis is established HIV/HCV-coinfected patients have more severe
liver injury and a worse prognosis than do patients with HCV infection
alone.
How
can Hepatitis C infection be prevented?
There
is no effective vaccine available commercially at present. Therefore a
major effort should be placed on counselling both HCV-infected
patients and those at risk of infection. Adequate sterilisation of
medical and surgical equipment is mandatory. HCV-infected patients
should be instructed to avoid sharing razors and toothbrushes and to
cover any open wounds. In addition, safe sexual practices, such as the
use of latex condoms, should be encouraged in patients with multiple
sexual partners. Because of the low rate of transmission from mother
to child, pregnancy is not contraindicated in HCV-infected women.
Breast-feeding is also not contraindicated.
The
primary goal of therapy for HCV infection is to eradicate the
infection early in the course of the disease to prevent progression to
advanced liver disease and eventually to liver cancer. A lesser goal
of therapy is to reduce the secondary spread of infection by
eradicating viremia. Loss of hepatitis C by molecular tests and
normalisation of liver enzyme levels have been used as treatment end
points. New formulations of interferon, pegylated interferon's, have
been developed recently allowing once-weekly dosing. These new
interferon's are able to sustain more uniform levels as opposed to the
fluctuations observed with every-other-day dosing and consequently
enhance viral suppression. Current standard treatment is either
standard or pegylated interferon given subcutaneously combined with
ribavirin orally. Usual treatment duration is 24-48 weeks.
Important
facts to know
1.
The risk of spreading Hepatitis C through normal household contact is
very low, Oral transmission of HCV has not been proven, so you can hug
and kiss your family and friends. Breast milk, semen, urine, saliva,
and tears may contain the Hepatitis C virus. Do not share razors,
toothbrushes or any other personal hygiene instrument that could
contain blood particles and infect another. You can share bathroom
facilities. There is a two- three percent chance that HCV can be
transmitted through sexual intercourse. The presence of sexually
transmitted diseases (STD's) increase the risk of transmitting
hepatitis C. Inform your partner of your infection and if you are
sexually active with multiple partners, you should always use a
condom. Menstrual blood is known to carry HCV - women should avoid sex
during this time, You must not give blood or donate organs.
-
Senior Consultant Gastroenterologist, Apollo Hospital, Dr. Sanjay
Kumar Domani
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