Theory · 38. Chronic hepatitis B and C

Covers the definition of chronic hepatitis B and C as long-lasting liver infections caused by HBV and HCV, and their possible progression to cirrhosis, liver failure or hepatocellular carcinoma. It then compares routes of transmission and risk factors for each virus, the liver damage seen in pathogenesis, the mostly silent or flu-like symptoms, and liver ultrasound for detecting cirrhosis and cancer.

Inside: 7 sections · 4 labelled pictures · 8 flashcards · 1 min

Topic 36 of 88 in the MU Sofia syllabus for Internal Diseases (Dental Medicine, Year 4). The free AceMed note covers it in 7 sections, about 174 words (1 min of reading), with 8 flashcards.

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)