Hepatitis B pathophysiology

Hepatitis Main Page
Hepatitis B
Home
Patient Information
Overview
Historical Perspective
Pathophysiology
Causes
Differentiating Hepatitis B from other Diseases
Epidemiology and Demographics
Risk Factors
Screening
Natural History, Complications and Prognosis
Diagnosis
Diagnostic Criteria
History and Symptoms
Physical Examination
Laboratory Findings
CT
MRI
Ultrasound
Treatment
Medical Therapy
Surgery
Primary Prevention
Hepatitis B Vaccination
Hepatitis B Vertical transmission
Secondary Prevention
Cost-Effectiveness of Therapy
Future or Investigational Therapies
Case Studies
Case #1
Hepatitis B pathophysiology On the Web
Most recent articles
Most cited articles
Review articles
CME Programs
Powerpoint slides
Images
American Roentgen Ray Society Images of Hepatitis B pathophysiology All Images X-rays Echo & Ultrasound CT Images MRI
Ongoing Trials at Clinical Trials.gov
US National Guidelines Clearinghouse
NICE Guidance
FDA on Hepatitis B pathophysiology
CDC on Hepatitis B pathophysiology
Hepatitis B pathophysiology in the news
Blogs on Hepatitis B pathophysiology
Directions to Hospitals Treating Hepatitis B
Risk calculators and risk factors for Hepatitis B pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Pathophysiology

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.

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.