Definition:
Chronic hepatitis B and C are long-lasting viral infections of the liver, caused by Hepatitis B virus (HBV) and Hepatitis C virus (HCV), respectively. They persist for more than 6 months and can lead to cirrhosis, liver failure, or hepatocellular carcinoma.
Etiology:
Hepatitis B (HBV):
- DNA virus, transmitted via:
- Blood
- Sexual contact
- Vertical transmission (mother to child)
- Risk factors:
- Healthcare work
- Blood transfusions
- Dental/surgical procedures
- Tattooing/piercing
- Immunosuppression (e.g. chemotherapy may reactivate latent HBV)
Hepatitis C (HCV):
- RNA virus, transmitted mainly via blood
- High-risk scenarios:
- IV drug use
- Unsafe medical practices
- Blood transfusions before 1992
- Organ transplants
Pathogenesis:
- Chronic inflammation of the liver leads to:
- Portal tract infiltration with lymphocytes, plasma cells, sometimes lymphoid follicles
- Lobular necrosis, apoptosis
- Progressive fibrosis → cirrhosis
- Chronic infection persists when immune clearance is insufficient
- Hepatitis B: May integrate into host genome (oncogenic risk)
- Hepatitis C: Immune-mediated injury with fluctuating liver enzyme levels
Symptoms:
Often Asymptomatic, but may include:
- Fatigue
- Low-grade fever (HBV)
- Flu-like symptoms, jaundice (HCV)
- Arthralgia or arthritis
- Glomerulonephritis (especially in HBV and HCV)