Viral Hepatitis: Pathogenesis and clinical findings Infection with a virus that targets the
Authors: Sean Spence Tyler Anker Yan Yu Reviewers: Dean Percy Crystal Liu Sam Lee* * MD at time of publication
liver, e.g. HAV, HBV, HCV, HDV, HEV
Hepatocytes are invaded & damaged
Foreign particles and tissue damage activate immune systemàliver inflammation
Lysis (bursting) of hepatocytes
Infection with chronic viruses (HBV and HCV) persist over time and additional symptoms may develop
RUQ pain/tenderness
If infection is prolonged or severe, inflammation becomes systemic
Release of hepatocyte’s cellular contents into the bloodstream
Infection with acute viruses (HAV and HEV) resolve over time, and the symptoms above normalize
Notes:
• HDV can only infect people with concomitant HBV infection
• HAV and HBV vaccines are the only ones that currently exist
• Not all patients with viral hepatitis will develop each of these symptoms. The presentations vary.
Fever, nausea, vomiting ↑ serum ALT, AST
↓ Hepatic metabolic activity (e.g. reduction of gluconeogenesis) ↓Serum Glucose
↓ Synthesis of plasma proteins (albumin, clotting factors, etc) ↓ Albumin, ↑ INR
Abbreviations:
• HAV – Hepatitis A Virus
• HBV – Hepatitis B Virus
• HCV – Hepatitis C Virus
• HEV – Hepatitis E Virus
• RUQ – Right Upper Quadrant
• ALT – Alanine Aminotransferase
• AST – Aspartate Aminotransferase
• INR – International Normalized Ratio
↓ Bilirubin clearance from blood, bilirubin ends up under the skin Jaundice Portal Hypertension
Encephalopathy, Splenomegaly, Esophageal Varices, Ascites, Caput Medusae, Edema
Encephalopathy, Muscle Wasting, Metabolic Bone Disease, Terry’s Nails, Ascites, Bruising, Clubbing, Edema
Spider Nevi, Altered Hair Patterns, Testicular Atrophy, Gynecomastia, Palmar Erythema
Progressive deterioration in liver function, possibly ending up in cirrhosis. (See slide on “Cirrhosis: pathogenesis and complications” for more details on mechanisms and full explanations.)
Hepatic Insufficiency Hyperestrogenism
Legend:
Pathophysiology
Mechanism
Sign/Symptom/Lab Finding
Complications
Re-Published January 12, 2020 on www.thecalgaryguide.com