Hepatitis A virus (HAV), hepatitis B virus (HBV) and hepatitis C virus (HCV) cause 95% of viral hepatitis cases in the U.S. 

Epidemiology

• Transmission - variable according to virus
  • HAV, HEV - fecal-oral
  • HBV, HCV, HDV - IV drug abuse, sexual transmission, blood transfusions

Organism

• Diverse group of viruses that share a common ability to cause inflammation and necrosis of the liver
• Virus may persist in a chronic state (HBV, HCV, HDV)
  • Patients may remain chronic carriers
  • May cause the development of cirrhosis

Etiologies

• Viral
  • Hepatitis D virus (HDV) and hepatitis E virus (HEV) are very rare causes in the U.S.
  • Other viruses - Cytomegalovirus, EBV
• Nonviral
  • Toxins (alcohol, drugs such as acetaminophen)
  • Obesity (steatohepatitis)
  • Granulomatous diseases (tuberculosis, sarcoid tumors)
  • Genetic disorders (Wilson disease, hemochromatosis)
• Autoimmune

Risk Factors

• Children in daycare settings (HAV)
• Sexual transmission from HBV- or HCV-positive partner
• HIV-positive patients (HBV, HCV)
• IV drug abusers (HBV, HCV)
• Hemophiliacs (HCV)

Clinical Presentation

• May be difficult to diagnose clinically
• Frequently asymptomatic
  • May only have mild rise in aminotransferases (ALT, AST)
• Mild symptoms (malaise, fever, chills, depressed appetite)
• Similar symptoms among viral hepatitis types
• Jaundice is not a predominant symptom in most patients

Diagnosis

• Indications for testing
  • New onset of jaundice, anorexia or dark urine
  • Known exposure to hepatitis
  • Suspicion of chronic hepatitis (elevated liver enzyme)
• Laboratory testing
  • Screen for hepatitis A, B and C infections
  • Panel testing includes hepatitis B core antibody IgM, hepatitis A IgM, hepatitis C antibody and hepatitis B surface antigen
    • HAV antibodies positive indicates acute hepatitis A
    • HBV antibodies positive indicates acute hepatitis B or chronic hepatitis
    • HCV antibodies positive indicates acute hepatitis C or chronic hepatitis
  • For further evaluation of hepatitis, refer to specific hepatitis algorithms in ARUP Consult®

Differential Diagnosis

• Viral hepatitis (Epstein-Barr virus [EBV], cytomegalovirus [CMV], enterovirus [EV])
• Nonalcoholic steatohepatitis
• Alcoholic liver disease
• Toxin-induced hepatitis
• Granulomatous disease (tuberculosis, sarcoidosis)
• Autoimmune hepatitis
• Hereditary liver disease (Wilson disease, hemochromatosis, alpha-1 antitrypsin)

Prevention

• Chronic hepatitis is a public health concern for transmission, as well as the development of cirrhosis and hepatocellular carcinoma
• Vaccines are available to immunize against HAV and HBV

Treatment

• Acute disease - supportive
• Chronic disease - reduce or eliminate viral loads