The diagnosis and management of hepatitis C virus (HCV) disease has been well characterized, and specific groups have been identified as being at increased risk for infection. The Centers for Disease Control and Prevention (CDC) recommends that testing for hepatitis C be offered to persons in this increased risk group. Routine screening of the general population has not been recommended. In 2004, the U.S. Preventive Services Task Force recognized the health burden caused by HCV and advances in management but determined that there was insufficient evidence to recommend for or against routine screening for HCV infection in high-risk asymptomatic persons. Testing is recommended for persons with signs or symptoms of liver disease. Persons at high risk of infection include those who have ever injected illegal drugs; who received clotting factors made before 1987; who received blood or organs before July 1992; who ever received long-term hemodialysis; with unexplained abnormal alanine transaminase levels; and health care, emergency medical, and public safety workers with needlestick or mucosal exposures to HCV-positive women.
Alter and associates note that although there is no population-based evidence that treatment of HCV disease decreases morbidity or mortality from liver cirrhosis or primary liver cancer, the protracted course of this disease may mean that the benefits of treatment will only be noticeable after 20 to 30 years of follow-up evaluation. Depending on the viral genotype, current treatments result in sustained viral elimination in 40 to 85 percent of infected persons. This, with normalization of liver enzyme tests and improved liver histology, makes a strong case for identifying and treating asymptomatic infected persons. Other interventions include counseling, cessation of alcohol intake, and immunization against other forms of viral hepatitis. Access to health care services may slow down disease progression and reduce mortality. Waiting for symptoms may delay diagnosis and treatment until a time when therapy will not significantly impact survival.
The potential harms of testing asymptomatic high-risk persons include false-positive results, knowledge of HCV status, complications of invasive evaluation testing such as liver biopsy, and side effects of treatment. These potential harms can be minimized by confirmatory blood testing and reserving liver biopsies for situations in which the results will influence treatment recommendations. Limiting treatment to those most likely to benefit will improve the benefit-to-risk ratio of current treatment options. Appropriate counseling can help reduce personal upset and anxiety about the diagnosis.
The authors conclude that it is important to identify persons with chronic HCV infection early in the disease course. It seems inappropriate to delay testing until signs or symptoms are present because it is not certain that early intervention decreases HCV-related chronic disease. Testing should be offered to all persons at high risk for infection with appropriate counseling, medical evaluation, and treatment.