Hepatitis b

pathophysiology of hepatitis B

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

2. 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.

3. 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

4. HEPATITIS B VIRUS

5. 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 )

6. 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 .

7. REPLICATIVE CYCLE

8. Acute hepatitis B 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.

9. Chronic hepatitis B 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.

10. Who is more likely to get hepatitis B? 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.

11. What are the complications of hepatitis B? 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

12. What are the symptoms of hepatitis B? (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

13. 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).

14. What causes hepatitis B? 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

15. You can’t get hepatitis B from 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.

16. Lab diagnosis PCR ELISA TEST

17. Treatment No antiviral is typically used in acute hepatitis B. For c hronic 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 )

18. 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. .

19. 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.

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