• Clinical science

Hepatitis C

Summary

Hepatitis C is an infection caused by the hepatitis C virus (HCV), which attacks liver cells and causes liver inflammation. The virus is mainly transmitted parenterally, especially through IV drug use or needlestick injuries in healthcare settings. Most patients are asymptomatic in the acute phase, but may develop fever, malaise, fatigue, or jaundice. Transition to chronic infections occurs in up to 85% of cases since asymptomatic patients are rarely diagnosed and treated. Chronic infection is associated with increased mortality due to cirrhosis and hepatocellular carcinoma. Suspicion of HCV infection due to exposure, clinical presentation, or elevated aminotransferase levels should be followed up with HCV antibody and HCV RNA testing to confirm the diagnosis. Acute HCV infection is treated with interferon-α, while a combination of two direct-acting antivirals (e.g., ledipasvir, sofosbuvir) is recommended in cases of chronic infection. More than 90% of patients are cured with adequate treatment.

Definition

Acute HCV infection

Chronic HCV infection

References:[1]

Epidemiology

References:[2][3]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

Pathogen

  • Hepatitis C virus (HCV: RNA virus, flavivirus)
  • Chronic infectious risk is multifactorial and ultimately derives from the host's inability to achieve true immunity despite the production of neutralizing antibodies against the viral envelope
    • Flawed proofreading capability of RNA dependent RNA polymerase introduces mutations into genes encoding viral glycoprotein envelope, allowing for continuous novel antigen production
    • Rapid replication rate produces many antigenically unique viral envelopes
    • Consequently, the production of host antibodies is delayed relative to the production of new mutant virions so infection continues
  • There are six genotypes: In the US, the main ones are genotype 1 (65–80%) and genotype 2 (10–15%).
  • Reinfection with another HCV genotype is possible even after previous infection.

Transmission

  1. Parenteral
  2. Sexual: rare (in contrast to HBV and HIV)
  3. Perinatal (vertical)

High-risk groups for HCV infection

Patients with a medical history indicating a high risk for HCV infection should be tested!
References:[4][3][5]

Clinical features

  • Incubation period: 2 weeks to 6 months

Acute course

Symptoms are nonspecific and may be similar to those of other acute viral infections!

Chronic course

References:[6][1][3][7][8]

Diagnostics

References:[7][9][10][11]

Pathology

Differential diagnoses

The differential diagnoses listed here are not exhaustive.

Treatment

Acute hepatitis C

  • Goal: prevent transition to chronic infection!
  • Treatment: interferon-α or peginterferon-α (PEG-INF) for 6 months

There is no post-exposure prophylaxis available!

Chronic hepatitis C

Interferon and ribavirin are associated with severe side effects and teratogenicity!
References:[3][5][10][12][13]

Complications

References:[14][15]

We list the most important complications. The selection is not exhaustive.

Special patient groups

Considerations in pregnancy

References:[16][17]