pathophysiology of hepatitis B

1. Microbiology Presentation
TOPIC: HEPATITIS B
Prepared by: AMINA TARIQ

3. What is hepatitis B?
 Hepatitis B is a viral infection that
causes liver inflammation and damage.
 The hepatitis B virus (HBV)spreads through
contact with an infected person’s blood,
semen, or other body fluids.

4. The specificity of HBV for a liver cells is based
on two properties:
Virus specific receptors located on hepatocyte
cell membrane (facilitate entry)
And transcription factors found only in
hepatocyte that enhance viral mRNA syntesis

5. HEPATITIS B VIRUS

6. Properties
• HBV is a member of hepadnavirus family.
• It is a 42-nm enveloped viron,with an
icosahedral nucleocapsid core containing a
partialy double-stranded circular DNA
genome.
• The envelope contain a protien called the
surface antigen(HBsAg)

7. Conti….
• With in a core is a DNA Polymerase.
• The genome contains 4 genes, that encode 5
protiens;
• The S gene encodes the surface antigen,
• The C gene encodes the core and the e antigen,
• The P gene encodes the polymerase,
• And X gene encodes the X protien.

9. REPLICATIVE CYCLE

19. Acute hepatitis B is a short-term infection.
 Symptoms, they may last several weeks. In
some cases, symptoms last up to 6 months.
 Sometimes your body is able to fight off the
infection and the virus goes away.
 Most healthy adults and children older than 5
years old who have hepatitis B get better
without treatment.

20. Chronic hepatitis B is a long-lasting infection.
Chronic hepatitis B occurs when your body
isn’t able to fight off the virus and the virus
does not go away.
Chances of developing chronic hepatitis B are
greater if you are infected with the virus as a
young child.
 About 90 percent of infants infected with
hepatitis B develop a chronic infection.

21.  People are more likely to get hepatitis B if they are born to a
mother who has hepatitis B.
 People are also more likely to have hepatitis B if they
 are infected with HIV , because hepatitis B and HIV spread in
similar ways.
 have lived with or had sex with someone who has hepatitis B.
 work in a field, such as health care, in which they have contact
with blood, needles, or body fluids at work.
 have lived in or travel often to parts of the world where
hepatitis B is common .
 are taking medicines that weaken the immune system, such as
steroids or chemotherapy medicines.

22.  Chronic hepatitis B may lead to complications,
including cirrhosis, liver failure, and liver cancer.
 Early diagnosis and treatment of chronic hepatitis B
can lower your chances of developing these
complications

23. (Clinical finding)
 Some people have symptoms of acute hepatitis B within 2 to 5
months after they come in contact with the virus. These
symptoms may include:
 dark yellow urine
 feeling tired
 fever
 gray- or clay-colored stools
 joint pain
 loss of appetite
 nausea
 pain in your abdomen
 vomiting
 yellowish eyes and skin, called jaundice

25. • If you have chronic hepatitis B, you may not have
symptoms until complications develop, which
could be decades after you were infected.
• A high rate of hepatocellular carcinoma (HCC).

26.  The hepatitis B virus causes hepatitis B. The HBV spreads
through contact with an infected person’s blood, semen, or
other body fluids. Contact can occur by:
 being born to a mother with hepatitis B
 having unprotected sex with an infected person
 sharing drug needles or other drug materials with an infected
person
 getting an accidental stick with a needle that was used on an
infected person
 having contact with the blood or open sores of an infected
person
 using an infected person’s razor, toothbrush, or nail clippers

27. being coughed on or sneezed on by an infected
person
drinking water or eating food
hugging an infected person
shaking hands or holding hands with an infected
person
sharing spoons, forks, and other eating utensils
sitting next to an infected person
A baby can’t get hepatitis B from breast milk.

28. Lab diagnosis
• PCR
• ELISA TEST

29. Treatment
• No antiviral is typically used in acute hepatitis B.
• For chronic hepatitis B,Entecavir or Tenofovir
• Otheroral medicines include ,
• Lamivudine,adefovir and the combination of
tenofovir and emtricitabin is also used.
• Medicines that doctors can give as shots include
 interferon alfa-2b (Intron A)
 peginterferon alfa-2a (Pegasys)

30. Reduce your chance of infection
(Prevention)
 Vaccination : Recombinant vaccine , Vaccine can be
given to those who are at increased risk of HBV infection such
as health care workers. It is also given routinely to neonates as
universal vaccination in many countries.
 Hepatitis B Immunoglobulin - HBIG may be used to
protect persons who are exposed to hepatitis B. It is particular
efficacious within 48 hours of the incident.
 Other measures - screening of blood donors, blood and
body fluid precautions.
.

31. You can reduce your chance of hepatitis B
infection by:
not sharing drug needles or other drug materials
wearing gloves if you have to touch another
person’s blood or open sores.
making sure your tattoo artist or body piercer
uses sterile tools.
not sharing personal items such as toothbrushes,
razors, or nail clippers.

32. REFERENCES
o http://www.aafp.org/afp/2010/0415/p965.pdf
o http://www.aasld.org/publications/practice-
guidelines-0.
o https://www.niddk.nih.gov/health-information/liver-
disease/viral-hepatitis/hepatitis-b
o https://www.slideshare.net/huzaifahamed/hepatitis-
b-virus
o http://jvi.asm.org