Co-infection of hepatitis C virus (HCV) and the human immunodeficiency virus (HIV) occurs commonly because both viruses are transmitted in similar fashion, via exchange of blood.1
Intravenous (injection) drug use, where needles and other paraphernalia are shared, is the most common mode of transmission for HCV. An estimated 50% to 90% of injection drug users acquire HCV by sharing needles or other drug paraphernalia.2 Injection drug use is also a common mode of transmitting HIV. In the US, about 30% of people who are infected with HIV are also infected with HCV and about three quarters of HIV-positive injection drug users are also positive for HCV.3,4
HIV is much more easily transmitted via sexual intercourse than HCV. The risk of getting HCV via intercourse in a monogamous relationship is very low, but increases with multiple sex partners. The prevalence of HCV is about the same in homosexual men with HIV as it is in homosexual men without HIV, ranging from 4% to 8% (with regional differences).3,4
Perinatal transmission is another way in which both HIV and HCV can be transmitted. In fact, the risk of acquiring HCV during the period surrounding birth is increased if the mother is co-infected with HCV and HIV. Among mothers who test positive for the HCV virus, the rate of transmission to their infant is about 8%. Among mothers who are co-infected with both HCV and HIV, this rate increases to about 22%.5
HCV/HIV co-infection and fibrosis progression
HCV/HIV co-infection appears to speed up the development and progression of fibrosis and cirrhosis compared with HCV infection alone. The rapid development of fibrosis with HCV/HIV co-infection may be due to weakened immunity on a cellular level, resulting from the effect of HIV on immune function, leaving liver cells more susceptible HCV invasion.1A quarter to a half of co-infected people will experience progression of fibrosis in as little as three years.67
Risk for hepatocellular carcinoma
HCV/HIV co-infection also increases risk for development of hepatocellular carcinoma (HCC) (liver cancer). HIV itself is associated with an 8-fold increase in risk for HCC. People who are co-infected with HCV/HIV tend to develop HCC at an earlier age. In one study, average time to development of HCC from HCV infection was 26 years for people who had HCV/HIV co-infection compared with 34 years for those with HCV alone.8
Risk factors for progression of liver disease
As with people who are infected with HCV alone, certain factors increase risk of progression of liver disease in those who are co-infected with HCV/HIV. These include1 :
- Older age
- Alcohol use
- Elevations in liver enzymes called transaminases (alanine transaminase [ALT] and aspartate transaminase [AST])
- Fatty liver disease (steatosis)
Treatment of HCV in the HCV/HIV co-infected person
Because HCV/HIV co-infection can speed up the progression of liver disease, especially in individuals who have advanced immunodeficiency, treatment to eradicate HCV is important. The goal of HCV antiviral therapy is to cure the HCV infection. A cure can provide important benefits, including9:
- Delayed progression or improvement of fibrosis
- Reduced risk for complications from liver disease
- Reduced risk for HCC
Does HIV affect response to HCV antiviral therapy?
People with HIV/HCV co-infection tend to have lower response rates to treatment with peginterferon + ribavirin. However, with newer treatment regimens including direct-acting antiviral agents (DAAs), treatment responses appear to be comparable for co-infected and mono-infected individuals.1
Who is a candidate for treatment?
All people who are co-infected with HCV and HIV should be considered for HCV antiviral treatment because of the risks associated with co-infection and the benefits associated with HCV cure. However, there may be contraindications that preclude an individual from receiving a specific treatment regimen, including HCV genotype, treatment history (previous treatment failure), and cirrhosis. The most common contraindication to treatment has been an inability to use interferon. However, there are now effective interferon-free treatment regimens that are safe and well tolerated and available to some HCV/HIV co-infected individuals. In the coming years, more interferon-free treatment options will become available for this group.
Selection of HCV antiviral treatment regimen for HCV/HIV co-infected individuals is generally the same as for mono-infected individuals. Selection of treatment regimen depends primarily on genotype, prior treatment history, stage of fibrosis, eligibility for interferon, and potential drug interactions between antiretroviral (HIV) therapy and HCV antiviral medications.
Learn more about recommended treatment options for individuals with HIV/HCV co-infection.