Clinical Review

Hepatitis C: the silent epidemic

Author and Disclosure Information

Though frequently asymptomatic in its initial stages, hepatitis C infection can have serious consequences, including cirrhosis, liver failure, cancer, and death. Early detection of the virus is beneficial, as it enables women to take advantage of increasingly effective treatments and alerts them to the need for preconception counseling.


 

References

Key points
  • The hepatitis C virus (HCV) is the leading cause of chronic liver disease and the leading indication for liver transplantation in the United States.
  • In the United States, 3.9 million people have been infected with HCV, with an overall prevalence of 1.8%. In females, prevalence is highest during the childbearing years, peaking at age 35.
  • Injection-drug use accounts for 60% of infections, while the transfusion of blood or blood products accounts for another 10%.
  • About 15% of people with acute HCV infection clear the virus; the rest develop chronic infection.
  • During chronic infection, most patients are asymptomatic or have mild, nonspecific symptoms such as fatigue.
  • Combination therapy with interferon alpha and ribavirin elicits a sustained virologic response rate of 40%, and newer therapy with pegylated interferon alpha and ribavirin improves the rate to 54%.
  • Perinatal transmission in women with chronic HCV infection occurs at an average rate of 5%.

The hepatitis C virus (HCV) was first identified in 1989 as the cause of non-A, non-B hepatitis infections. Since its discovery, HCV has become the most common chronic blood-borne infection in the United States: Approximately 2.7 to 3.5 million people have chronic HCV infection,1,2 as compared with 1.25 million people with chronic hepatitis B virus infection and 1 million with the human immunodeficiency virus (HIV). In addition, HCV infection is the leading cause of chronic liver disease and the leading indication for liver transplantation in the United States. Some call HCV infection “the silent epidemic,” since 75% of people infected are asymptomatic and chronic manifestations don’t appear for 1 to 2 decades.

In 1998, the Centers for Disease Control and Prevention (CDC) issued guidelines for screening for HCV infection ( Table 1).3 The American College of Obstetricians and Gynecologists (ACOG) advocates screening for HCV infection at the annual exam if the patient belongs to one of the CDC’s routine-screening categories.4 Although ACOG has not issued separate screening guidelines for obstetric patients, some practitioners have advocated screening based on risk factors, as listed in the CDC’s routine-screening categories.5

HCV accounts for about 20% of acute hepatitis cases in the U.S.

Because Ob/Gyns are increasingly likely to encounter patients with positive HCV blood-screening results, they should be prepared to answer the following inquiries: What is hepatitis C? How is it diagnosed and transmitted? What is the natural history of the infection? Is there a treatment for it? How will HCV infection affect pregnancy?

This review addresses those questions.

What is hepatitis C?

Hepatitis C is a liver disease caused by the HCV, an RNA virus of the Flavivirus family, which includes the dengue and yellow fever viruses. Worldwide, approximately 170 million people are infected with HCV, with a prevalence ranging from a low of 0.15% in Scandinavia to a high of 38% in northern Egypt.6,7 In the United States, 3.9 million people have been infected with HCV, with an overall prevalence of 1.8%.1 U.S. prevalence rates by gender and age reveal that more males are infected than females and that, in females, prevalence is highest during the childbearing years, peaking at age 35.

TABLE 1

Recommendations for hepatitis C virus screening

PEOPLE WHO SHOULD BE TESTED ROUTINELY
  • Persons who have ever injected illegal drugs
  • Persons with selected medical conditions, including: persons who have ever undergone chronic hemodialysis persons with evidence of liver disease, such as persistently abnormal ALT levels
  • Prior recipients of transfusions or organ transplants, including: recipients of clotting factor concentrates produced before 1987 persons who received a transfusion of blood or blood components before July 1992 persons who received an organ transplant before July 1992 persons who were notified that they received clotting factor concentrates, blood components, or organ transplants from a donor who later tested positive for HCV infection
  • Persons with a recognized exposure, including: health-care, emergency medical, and public safety workers after sticks with needles or sharps or mucosal exposure to HCV-positive blood children born to HCV-positive women
PEOPLE FOR WHOM ROUTINE TESTING IS OF UNCERTAIN NEED
  • Recipients of transplanted tissue, e.g., corneal or musculoskeletal tissue, skin, ova, or sperm
  • Users of intranasal cocaine or other noninjected illegal drugs
  • Persons with a history of tattooing or body piercing
  • Persons with a history of multiple sex partners or sexually transmitted diseases
  • Long-term sex partners of HCV-positive persons
PEOPLE FOR WHOM ROUTINE TESTING IS NOT RECOMMENDED*
  • Health-care, emergency medical, and public safety workers
  • Pregnant women
  • Nonsexual household contacts of HCV-positive persons
  • The general population
* Except in cases where risk factors are present ALT=alanine aminotransferase; HCV=hepatitis C virus
Source: Centers for Disease Control and Prevention

How is HCV infection diagnosed?

The initial screening test is an enzyme immunoassay (EIA) for the antibody to HCV. Currently, a third-generation EIA is used, with a sensitivity and specificity of 99% in immunocompetent people. If the EIA is positive, the practitioner may proceed to a confirmatory recombinant immunoblot assay (RIBA) in individuals with a low pretest probability, or to direct measurement of HCV RNA by reverse-transcription polymerase chain reaction (PCR) in individuals with a high pretest probability. Figure 1 depicts the HCV testing algorithm recommended by the CDC.

Pages

Next Article: