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Hepatitis
Disease
Hepatitis
A
Hepatitis
B
Hepatitis
C
Hepatitis
D
Clinical
Features
Geographic
Distribution of HDV
Infection
Prevention
Modes of
Transmission
Summary
All Hepatitis
HAV
/ HBV / HCV /
HDV
Hepatitis
E (HEV)
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ชมรมเรารักสุขภาพ
ไทยแล็ปออนไลน์
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เชื้อไวรัสตับอักเสบดี พบในผู้ป่วยกลุ่มที่มีการฉีดยาเสพติด รับเชื้อจากการใช้เข็มและกระบอกฉีดร่วมกัน
เชื้อชนิดนี้ไมาสามารถเพิ่มจำนวนในเซลล์ตับได้โดยลำพัง แต่จะติดเชื้อร่วมกับตับอักเสบบี
แล้วจึงเพิ่ม
จำนวนไวรัสทั้งตับอักเสบ ดี และ บี
การติดเชื้อ เช่นเดียวกับโรคตับอักเสบบี ตับอักเสบดีทำให้เกิดโรคตับอักเสบรุนแรงกว่าเชื้ออื่นๆ
และอาจ
ติดเชื้อเรื้อรัง จนกลายเป็นตับแข็งในอัตราค่อนข้างสูงๆ
การป้องกัน โดยการฉีดวัคซีนป้องกันไวรัสตับอักเสบบี จะป้องกันโรคนี้ได้ด้วย
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THIS REVIEW was written by Howard J. Worman, M.D.,
Departments of Medicine and of Anatomy and Cell Biology, College
of Physicians and Surgeons, Columbia
University, New York, NY 10032. Dr. Worman has more reviews
available at his Current
Papers in Liver Disease site.
"The Hepatitis D Virus"
Hepatitis D
By Howard J. Worman, M. D.
The hepatitis D virus (also called delta virus) is a small
circular RNA virus. The hepatitis D virus is replication defective
and therefore cannot propagate in the absence of another virus. In
humans, hepatitis D virus infection only occurs in the presence of
hepatitis B infection.
Hepatitis D virus infection is transmitted by blood and blood
products. The risk factors for infection are similar to those for
hepatitis B virus infection. The hepatitis D virus most often
infects intravenous drug users.
A patient can acquire hepatitis D virus infection at the same
time as he/she is infected with the hepatitis B virus. This is
called co-infection. A patient with hepatitis B can be infected
with hepatitis D virus at any time after acute hepatitis B virus
infection. This is called super-infection.
Hepatitis D virus super-infection should be suspected in a
patient with chronic hepatitis B whose condition suddenly worsens.
There is usually an obvious history of continued exposure to blood
or blood products (eg. an active intravenous drug user). A
particularly aggressive acute hepatitis B infection could suggest
hepatitis D co-infection. Co-infection or super-infection with
hepatitis D virus in a patient with hepatitis B is diagnosed by
the presence of antibodies against the hepatitis D virus. IgM
antibodies indicate acute infection.
Interferon-alpha is used to treat patients with chronic
hepatitis B and hepatitis D infection. Some studies have suggested
that a dose higher than that usually used for hepatitis B
infection may be beneficial.
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Hepatitis D Virus
Hepatitis D Virus (HDV) or
delta virus is a unique incomplete virus that requires hepatitis B
virus (HBV) for its replication. The RNA genome is covered by an outer
coat of hepatitis B surface antigen. HDV infection occurs worldwide
but is endemic in certain regions including the Mediterranean basin,
the Balkan peninsula, the former Soviet Union, parts of Africa and the
Middle East and the Amazon basin of South America. In these regions,
spread is typically intrafamilial and through sexual contact.
In non-endemic regions, such as
North America, HDV infection is uncommon in the general population but
does occur in intravenous drug users and persons with frequent
exposure to blood products (e.g. hemophiliacs) as well as their sexual
contacts.
The clinical course of HDV
infection depends largely on whether the virus was acquired as a
coinfection with hepatitis B or as a superinfection in an individual
with a previously established chronic HDV infection. When acquired as
a coinfection, HDV typically results in acute self-limited hepatitis
although fulminant hepatitis and death are well described. As a
superinfection the typical course is one of a rapidly progressive
chronic hepatitis.
Prevention of HDV infection is
based on HDV vaccination in susceptible individuals. Patients with
chronic HDV infection at risk of HDV infection are advised to avoid
parenteral and unprotected sexual exposures.
Hepatitis D - Clinical
Features
- Coinfection
- severe acute disease
- low risk of chronic
infection
- Superinfection
- usually develop chronic
HDV infection high
- risk of severe chronic
liver disease
Notes:
HDV infection can be acquired either as a co-infection with HBV or as
a superinfection of persons with chronic HBV infection. Persons with
HBV-HDV co-infection may have more severe acute disease and a higher
risk of fulminant hepatitis (2%-20%) compared with those infected with
HBV alone; however, chronic HBV infection appears to occur less
frequently in persons with HBV-HDV co-infection. Chronic HBV carriers
who acquire HDV superinfection usually develop chronic HDV infection.
In long-term studies of chronic HBV carriers with HDV superinfection,
70%-80% have developed evidence of chronic liver diseases with
cirrhosis compared with 15%-30% of patients with chronic HBV infection
alone.
Notes:
The serologic course of HDV infection varies depending on whether the
virus is acquired as a co-infection with HBV or as a superinfection of
a person with chronic HBV infection. In most persons with HBV-HDV
co-infection, both IgM antibody to HDV (anti-HDV) and IgG anti-HDV are
detectable during the course of infection. However, in about 15% of
patients the only evidence of HDV infection may be the detection of
either IgM anti-HDV alone during the early acute period of illness or
IgG anti-HDV alone during convalescence. Anti-HDV generally declines
to sub-detectable levels after the infection resolves and there is no
serologic marker that persists to indicate that the patient was ever
infected with HDV. Hepatitis Delta antigen (HDAg) can be detected in
serum in only about 25% of patients with HBV-HDV co-infection. When
HDAg is detectable it generally disappears as HBsAg disappears and
most patients do not develop chronic infection. Tests for IgG anti-HDV
are commercially available in the United States. Tests for IgM anti-HDV,
HDAg and HDV RNA by PCR are only available in research laboratories.
Notes:
In patients with chronic HBV infection who are super-infected with HDV
several characteristic serologic features generally occur, including:
1) the titer of HBsAg declines at the time HDAg appears in the serum,
2) HDAg and HDV RNA remain detectable in the serum because chronic HDV
infection generally occurs in most patients with HDV superinfection,
unlike the case with co-infection, 3) high titers of both IgM and IgG
anti-HDV are detectable, which persist indefinitely.
GEOGRAPHIC
DISTRIBUTION OF HDV INFECTION
Notes:
In general, the global pattern of HDV infection corresponds to the
prevalence of chronic HBV infection; however, several distinct
features of the distribution of HDV infection have been identified. In
countries with a low prevalence of chronic HBV infection, HDV
prevalence is generally low among both asymptomatic HBV carriers
(<10%) and among patients with chronic HBV-related liver disease
(<25%). HDV infection in these countries occurs most commonly among
injecting drug users and persons with hemophilia. In countries with
moderate and high levels of chronic HBV prevalence, the prevalence of
HDV infection is highly variable. In southern Italy and in parts of
Russia and Romania, the prevalence of HDV infection is very high among
both asymptomatic HBV carriers (>20%) and among patients with HBV-related
chronic liver disease HBV (>60%). Other countries, including
northern Italy, Spain, Turkey, and Egypt, have a moderate prevalence
of HDV infection among asymptomatic HBV carriers (10%-19%) and among
patients with chronic HBV-related liver disease (30%-50%). However, in
most of Southeast Asia and China, where the prevalence of chronic HBV
infection is very high, HDV infection is uncommon. In some South
American countries in the Amazon River Basin, periodic epidemics of
HDV infection have occurred among chronic HBV carriers in relatively
isolated regions. Disease related to HDV infection in these outbreaks
has been very severe, with rapid progression to fulminant hepatitis
and case-fatality rates of 10%-20%. The cause of the atypical course
of HDV infection in these populations is unknown.
*(Note: The map of
anti-HDV prevalence generalizes available data and patterns may vary
within countries.)
Hepatitis D - Prevention
- HBV-HDV Coinfection
Pre or postexposure prophylaxis to prevent
- HBV infection HBV-HDV
Superinfection
Education to reduce risk behaviors among persons with chronic HBV
infection
Notes:
Because HDV is dependent on HBV for replication, HBV-HDV co-infection
can be prevented with either pre- or postexposure prophylaxis for HBV.
However, no products exist to prevent HDV superinfection of persons
with chronic HBV infection. Thus, prevention of HDV superinfection
depends primarily on education to reduce risk behaviors.
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Hepatitis D Virus
Modes of Transmission
- Percutanous exposures
- Permucosal
Notes:
The modes of HDV transmission are similar to those for HBV, with
percutaneous exposures the most efficient. Sexual transmission
of HDV is less efficient than for HBV. Perinatal HDV
transmission is rare.
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Fact
Sheet
| SIGNS
& SYMPTOMS |
About
30% of persons have no signs or symptoms.
Signs and symptoms are less common in children than
adults. |
- jaundice
- fatigue
- abdominal
pain
|
- loss of
appetite
- nausea,
vomiting
- joint pain
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| CAUSE |
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| LONG-TERM
EFFECTS WITHOUT VACCINATION |
Chronic
infection occurs in:
- 90% of
infants infected at birth
- 30% of
children infected at age 1 - 5 years
- 6% of
persons infected after age 5 years
Death from
chronic liver disease occurs in:
- 15-25% of
chronically infected persons
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| TRANSMISSION |
- Occurs when
blood or body fluids from an infected person
enters the body of a person who is not immune.
- HBV is
spread through having sex with an infected person
without using a condom, sharing needles or
"works" when "shooting" drugs,
through needlesticks or sharps exposures on the
job, or from an infected mother to her baby during
birth.
Persons
at risk for HBV infection might also be at risk for
infection with hepatitis C virus (HCV) or HIV.
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| RISK
GROUPS
|
- Persons with
multiple sex partners or diagnosis of a sexually
transmitted disease
- Men who have
sex with men
- Sex contacts
of infected persons
- Injection
drug users
- Household
contacts of chronically infected persons
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- Infants born
to infected mothers
- Infants/children
of immigrants from areas with high rates of HBV
infection (view
map)
- Health care
and public safety workers
- Hemodialysis
patients
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| PREVENTION |
- Hepatitis B
vaccine is the best protection.
- If you are
having sex, but not with one steady partner, use
latex condoms correctly and every time you have
sex.
- If you are
pregnant, you should get a blood test for
hepatitis B; Infants born to HBV-infected mothers
should be given H-BIG (hepatitis B immune
globulin) and vaccine within 12 hours after birth.
- Do not shoot
drugs; if you shoot drugs, stop and get into a
treatment program; if you can't stop, never share
needles, syringes, water, or "works",
and get vaccinated against hepatitis A and B.
- Do not share
personal care items that might have blood on them
(razors, toothbrushes).
- Consider the
risks if you are thinking about getting a tattoo
or body piercing. You might get infected if the
tools have someone else's blood on them or if the
artist or piercer does not follow good health
practices.
- If you have
or had hepatitis B, do not donate blood, organs,
or tissue.
- If you are a
health care or public safety worker, get
vaccinated against hepatitis B, and always follow
routine barrier precautions and safely handle
needles and other sharps.
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| VACCINE
RECOMMENDATIONS |
- Hepatitis B
vaccine available since 1982
- Routine
vaccination of 0-18 year olds
- Vaccination
of risk groups of all ages (see section on
risk groups)
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| TREATMENT
& MEDICAL MANAGEMENT
National
Institutes of Health fact sheet on treatment
|
- HBV infected
persons should be evaluated by their doctor for
liver disease.
- Alpha
interferon and lamivudine are two drugs licensed
for the treatment of persons with chronic
hepatitis B. These drugs are effective in up
to 40% of patients.
- These drugs
should not be used by pregnant women.
- Drinking
alcohol can make your liver disease worse.
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| TRENDS
& STATISTICS
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- Number of
new infections per year has declined from an
average of 450,000 in the 1980s to about 80,000 in
1999.
- Highest rate
of disease occurs in 20-49-year-olds.
- Greatest
decline has happened among children and
adolescents due to routine hepatitis B
vaccination.
- Estimated
1.25 million chronically infected Americans, of
whom 20-30% acquired their infection in childhood.
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Hepatitis
A
(HAV)
|
Hepatitis
B
(HBV)
|
Hepatitis
C
(HCV)
|
Hepatitis
D
(HDV)
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What is
it?
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HAV
is a virus
that causes inflammation of
the liver. It does not lead to chronic disease.
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HBV
is a virus
That causes inflammation of
the liver. It can cause liver cell damage, leading to
cirrhosis and cancer.
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HCV
is a virus
that causes inflammation of
the liver. It can cause liver cell damage, leading to
cirrhosis and cancer.
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HDV
is a virus
that causes inflammation of
the liver. It only infects those persons with HBV.
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|
Incubation
Period
|
2
to 7 weeks.
Average 4 weeks.
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6
to 23 weeks.
Average 17 weeks.
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2
to 25 weeks.
Average 7 to 9 wks.
|
2
to 8 weeks. |
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How is it
Spread?
|
Transmitted
by fecal/oral route, through close person to person
contact or ingestion of contaminated food and water. |
Contact
with infected blood, seminal fluid, vaginal secretions,
contaminated needles, including tattoo and body-piercing
tools. Infected mother to newborn. Human bite. Sexual
contact. |
Contact
with infected blood, contaminated IV needles, razors, and
tattoo or body- piercing tools. Infected mother to
newborn. NOT easily spread through sex. |
Contact
with infected blood, contaminated needles. Sexual contact
with HDV infected person. |
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Symptoms
|
May
have none. Others may have light stools, dark urine,
fatigue, fever, nausea, vomiting, abdominal pain, and
jaundice. |
May
have none. Some persons have mild flu-like symptoms, dark
urine, light stools, jaundice, fatigue and fever. |
Same
as HBV |
Same
as HBV |
|
Treatment
of Chronic Disease
|
Not
applicable. |
Interferon
and Lamivudine with varying success. |
Interferon
and combination therapies with varying success. |
Interferon
with varying success. |
|
Vaccine
|
Two
doses of vaccine to anyone over 2 yrs of age or older. |
Three
doses may be given to persons of any age. |
None |
HBV
vaccine prevents HDV infection. |
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Who is at
Risk?
|
Household
or sexual contact with an infected person or living in an
area with HAV outbreak. Travelers to developing countries,
persons engaging in anal/oral sex and injection drug
users. |
Infants
born to infected mother, having sex with an infected
person or multiple partners, injection drug users,
emergency responders, healthcare workers, persons engaging
in anal/oral sex, and hemodialysis patients. |
Blood
transfusion recipients before 1992, healthcare workers,
injection drug users, hemodialysis patients, infants born
to infected mother, multiple sex partners. |
Injection
drug users, persons engaging in anal/oral sex and those
having sex with an HDV infected person. |
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Prevention
|
Immune
Globulin within 2 wks of exposure. Vaccination. Washing
hands with soap and water after going to the toilet. Use
household bleach (10 parts water to 1 part bleach)
to clean surfaces contaminated with feces, such as
changing tables. Safe sex. |
Immune
Globulin within 2 wks of exposure. Vaccination provides
protection for 18 years. Clean up infected blood with
household bleach and wear protective gloves. Do not share
razors, toothbrushes, or needles. Safe sex. |
Clean
up spilled blood with household bleach. Wear gloves when
touching blood. Do not share razors, toothbrushes, or
needles with anyone. Safe sex. |
Hepatitis
B vaccine to prevent HBV infection. Safe sex. |
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