Hepatitis B pathophysiology: Difference between revisions
No edit summary |
Joao Silva (talk | contribs) No edit summary |
||
| Line 2: | Line 2: | ||
{{Hepatitis B}} | {{Hepatitis B}} | ||
{{CMG}} | {{CMG}} | ||
== | |||
==Pathogenesis== | |||
Intracellular HBV is non-cytopathic and causes little or no damage to the cell.<ref name=WHO>{{cite web | title = Hepatitis B | url = http://www.who.int/csr/disease/hepatitis/HepatitisB_whocdscsrlyo2002_2.pdf }}</ref> | |||
===Transmission=== | ===Transmission=== | ||
Transmission results from exposure to infectious blood or body fluids containing blood. Possible forms of transmission include (but are not limited to) [[unprotected sex|unprotected sexual contact]], [[blood transfusion]]s, [[needle sharing|re-use of contaminated needles]] and syringes, and [[vertical transmission]] from mother to child during childbirth. Without intervention, a mother who is positive for the hepatitis B surface antigen confers a 20% risk of passing the infection to her offspring at the time of birth. This risk is as high as 90% if the mother is also positive for the hepatitis B e <!-- sic! see Replication, above --> antigen. HBV can also be transmitted between family members within households, possibly by contact of nonintact skin or mucous membrane with secretions or saliva containing HBV.<ref> name="pmid791124">{{cite journal |author=Petersen NJ, Barrett DH, Bond WW, Berquist KR, Favero MS, Bender TR, Maynard JE |title=Hepatitis B surface antigen in saliva, impetiginous lesions, and the environment in two remote Alaskan villages |journal=Appl. Environ. Microbiol. |volume=32 |issue=4 |pages=572-574 |year=1976 |pmid=791124}}</ref> | Transmission results from exposure to infectious blood or body fluids containing blood. Possible forms of transmission include (but are not limited to) [[unprotected sex|unprotected sexual contact]], [[blood transfusion]]s, [[needle sharing|re-use of contaminated needles]] and syringes, and [[vertical transmission]] from mother to child during childbirth. Without intervention, a mother who is positive for the hepatitis B surface antigen confers a 20% risk of passing the infection to her offspring at the time of birth. This risk is as high as 90% if the mother is also positive for the hepatitis B e <!-- sic! see Replication, above --> antigen. HBV can also be transmitted between family members within households, possibly by contact of nonintact skin or mucous membrane with secretions or saliva containing HBV.<ref> name="pmid791124">{{cite journal |author=Petersen NJ, Barrett DH, Bond WW, Berquist KR, Favero MS, Bender TR, Maynard JE |title=Hepatitis B surface antigen in saliva, impetiginous lesions, and the environment in two remote Alaskan villages |journal=Appl. Environ. Microbiol. |volume=32 |issue=4 |pages=572-574 |year=1976 |pmid=791124}}</ref> | ||
Revision as of 14:29, 29 July 2014
|
Hepatitis B |
|
Diagnosis |
|
Treatment |
|
Case Studies |
|
Hepatitis B pathophysiology On the Web |
|
American Roentgen Ray Society Images of Hepatitis B pathophysiology |
|
Risk calculators and risk factors for Hepatitis B pathophysiology |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Pathogenesis
Intracellular HBV is non-cytopathic and causes little or no damage to the cell.[1]
Transmission
Transmission results from exposure to infectious blood or body fluids containing blood. Possible forms of transmission include (but are not limited to) unprotected sexual contact, blood transfusions, re-use of contaminated needles and syringes, and vertical transmission from mother to child during childbirth. Without intervention, a mother who is positive for the hepatitis B surface antigen confers a 20% risk of passing the infection to her offspring at the time of birth. This risk is as high as 90% if the mother is also positive for the hepatitis B e antigen. HBV can also be transmitted between family members within households, possibly by contact of nonintact skin or mucous membrane with secretions or saliva containing HBV.[2]
Immunopathogenesis
During HBV infection, the host immune response causes both hepatocellular damage and viral clearance. While the innate immune response does not play a significant role in these processes, the adaptive immune response, particularly virus-specific cytotoxic T lymphocytes (CTLs), contributes to nearly all of the liver injury associated with HBV infection. By killing infected cells and by producing antiviral cytokines capable of purging HBV from viable hepatocytes, CTLs also eliminate the virus.[3]
References
- ↑ "Hepatitis B" (PDF).
- ↑ name="pmid791124">Petersen NJ, Barrett DH, Bond WW, Berquist KR, Favero MS, Bender TR, Maynard JE (1976). "Hepatitis B surface antigen in saliva, impetiginous lesions, and the environment in two remote Alaskan villages". Appl. Environ. Microbiol. 32 (4): 572–574. PMID 791124.
- ↑ {{cite journal | author=Iannacone M. et al | title=Pathogenetic and antiviral immune responses against hepatitis B virus | journal=Future Virology | year=2006 | pages=189-196 | volume=1 | issue=2