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Hepatitis C, Acute

By

Sonal Kumar

, MD, MPH, Weill Cornell Medical College

Last full review/revision Dec 2020| Content last modified Dec 2020
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Hepatitis C is caused by an RNA virus that is often parenterally transmitted. It sometimes causes typical symptoms of viral hepatitis, including anorexia, malaise, and jaundice but may be asymptomatic. Fulminant hepatitis and death rarely occur. Chronic hepatitis develops in about 75% and can lead to cirrhosis and rarely hepatocellular carcinoma. Diagnosis is by serologic testing. Treatment is with antiviral drugs. No vaccine is available.

In the US, 3621 cases of acute hepatitis C infection were reported in 2018. However, because many cases are not recognized or not reported, the Centers for Disease Control and Prevention (CDC) estimates that the actual number of new infections was over 50,300 in 2018 (1 General reference Hepatitis C is caused by an RNA virus that is often parenterally transmitted. It sometimes causes typical symptoms of viral hepatitis, including anorexia, malaise, and jaundice but may be asymptomatic... read more ).

Hepatitis C virus (HCV) is a single-stranded RNA flavivirus that causes acute viral hepatitis Overview of Acute Viral Hepatitis Acute viral hepatitis is diffuse liver inflammation caused by specific hepatotropic viruses that have diverse modes of transmission and epidemiologies. A nonspecific viral prodrome is followed... read more and is a common cause of chronic viral hepatitis Overview of Chronic Hepatitis Chronic hepatitis is hepatitis that lasts > 6 months. Common causes include hepatitis B and C viruses, nonalcoholic steatohepatitis (NASH), alcohol-related liver disease, and autoimmune liver... read more . Six major HCV subtypes exist with varying amino acid sequences (genotypes); these subtypes vary geographically and in virulence and response to therapy. HCV can also alter its amino acid pattern over time in an infected person, producing quasispecies.

HCV infection sometimes occurs simultaneously with specific systemic disorders, including the following:

The mechanisms are uncertain.

Up to 20% of patients with alcoholic liver disease Alcohol-Related Liver Disease Alcohol consumption is high in most Western countries. According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), 8.5% of US adults are estimated to have... read more Alcohol-Related Liver Disease harbor HCV. The reasons for this high association are unclear because concomitant alcohol and drug use accounts for only a portion of cases. In these patients, HCV and alcohol act synergistically to worsen liver inflammation and fibrosis.

Transmission of hepatitis C

Infection is most commonly transmitted through blood, primarily when parenteral drug users share needles, but also through tattoos or body piercing with nonsterile equipment.

Sexual transmission and vertical transmission of hepatitis C from mother to infant are relatively rare.

Transmission of hepatitis C through blood transfusion has become very rare since the advent of screening tests for donated blood.

Some sporadic cases occur in patients without apparent risk factors.

HCV prevalence varies with geography and other risk factors.

General reference

  • 1. CDC: Hepatitis C questions and answers for health professionals. Accessed 11/29/20.

Symptoms and Signs of Acute Hepatitis C

Hepatitis C may be asymptomatic during the acute infection. Its severity often fluctuates, sometimes with recrudescent hepatitis and roller-coaster aminotransferase levels for many years or even decades. Fulminant hepatitis Fulminant Hepatitis Fulminant hepatitis is a rare syndrome of rapid (usually within days or weeks), massive necrosis of liver parenchyma and a decrease in liver size (acute yellow atrophy); it usually occurs after... read more is extremely rare.

Diagnosis of Acute Hepatitis C

  • Serologic testing

  • HCV RNA measurement

If acute viral hepatitis is suspected, the following tests are done to screen for hepatitis viruses A, B, and C:

  • IgM antibody to hepatitis A virus (IgM anti-HAV)

  • Hepatitis B surface antigen (HBsAg)

  • IgM antibody to hepatitis B core (IgM anti-HBc)

  • Antibody to HCV (anti-HCV) and HCV RNA

In hepatitis C, serum anti-HCV represents chronic, past, or acute infection; the antibody is not protective. When cases are unclear or when suspicion for hepatitis C is high, HCV RNA is measured. Anti-HCV usually appears within 2 weeks of acute infection but is sometimes delayed; however, HCV RNA is positive sooner.

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Other tests

Liver tests are needed if not previously done; they include serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase.

Other tests should be done to evaluate liver function and disease severity; they include serum albumin, bilirubin, platelet count, and prothrombin time/international normalized ratio (PT/INR).

Treatment of Acute Hepatitis C

  • Antiviral therapy

There are a number of highly effective direct-acting antiviral drugs Hepatitis C is a common cause of chronic hepatitis. It is often asymptomatic until manifestations of chronic liver disease occur. Diagnosis is confirmed by finding positive anti-HCV and positive... read more (DAAs) for hepatitis C that may decrease the likelihood of developing chronic infection. Current recommendations are to start treatment after the initial diagnosis of acute HCV, without waiting for spontaneous resolution.

Alcohol and hepatotoxic drugs (eg, acetaminophen) should be avoided because it can increase liver damage. Restrictions on diet or activity, including commonly prescribed bed rest, have no scientific basis.

Viral hepatitis should be reported to the local or state health department.

Treatment reference

Prevention of Acute Hepatitis C

Patients should be advised to avoid high-risk behavior (eg, sharing needles to inject drugs, getting tattoos and body piercings).

Blood and other body fluids (eg, saliva, semen) are considered infectious. Risk of infection after a single needlestick exposure is about 1.8%. Barrier protection is recommended, but isolation of patients is of no value in preventing acute hepatitis C.

Risk of transmission from HCV-infected medical personnel appears to be low, and there are no CDC recommendations to restrict health care workers with hepatitis C infection.

Posttransfusion infection is minimized by avoiding unnecessary transfusions and screening all donors for hepatitis B and C. Screening has decreased the incidence of posttransfusion hepatitis B and hepatitis C, which are now extremely rare in the US.

No product exists for immunoprophylaxis of HCV. The propensity of HCV for changing its genome hampers vaccine development.

Preexposure or postexposure prophylaxis with antiviral therapy is not recommended.

Key Points

  • Hepatitis C is usually transmitted by parenteral contact with contaminated blood; transmission from mucosal contact with other body fluids and perinatal transmission from infected mothers are rare.

  • About 75% of patients with acute hepatitis C develop chronic hepatitis C, which leads to cirrhosis in 20 to 30%; some patients with cirrhosis develop hepatocellular carcinoma.

  • Diagnose by testing for antibody to HCV and HCV RNA.

  • Treat with antiviral drugs after initial diagnosis of hepatitis C, without waiting for spontaneous resolution.

  • There is no vaccine for hepatitis C.

More Information

  • CDC: Hepatitis C questions and answers for health professionals: This web site provides an overview of hepatitis C (including definitions, statistics, risk factors, and complications) and information about transmission, symptoms, diagnosis, and treatment, as well as hepatitis C and pregnancy. Accessed 11/29/20.

Drugs Mentioned In This Article

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TYLENOL
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