COMMENTARY

HIV and Hepatitis C Co-infection: Guideline and Commentary

Douglas G. Fish, MD

Disclosures

January 05, 2011

In This Article

Screening for and Diagnosis of Hepatitis C

Screening for HCV Infection

Recommendations. Clinicians should screen all HIV-infected patients for anti-HCV antibodies at baseline. (AII)

HIV-infected patients who are seronegative for HCV but have continued high-risk behaviors should be screened at least annually for HCV. Individuals at high risk include injection drug users (AII), MSM who don't use barrier protection (AII), or anyone with multiple sexual partners (AIII).

The high rate of HIV/HCV co-infection and the similar routes of transmission of both viruses underscore the importance of screening all HIV-infected patients for anti-HCV antibodies at baseline. HIV-infected patients with continued high-risk behaviors who are seronegative for HCV at baseline should receive annual testing thereafter.

A number of tests are available for HCV screening. The most readily available is the ELISA for anti-HCV antibodies. These antibodies are not protective, serving instead as a marker of present or past disease. Seroconversion with the ELISA antibody test occurs in 50% of patients within 9 weeks of exposure, in 80% within 15 weeks of exposure, and in at least 97% within 6 months of exposure. In addition to currently available ELISAs, the US Food and Drug Administration (FDA) has recently approved a rapid HCV test, the OraQuick® HCV Rapid Antibody Test, for patients at risk for HCV exposure. The ELISA tests are highly sensitive but relatively nonspecific, resulting in a low positive predictive value in low-prevalence populations.

Diagnosis of HCV Infection

Recommendations. Clinicians should confirm a reactive HCV ELISA antibody test with a quantitative HCV RNA assay. (AI) Negative HCV RNA test results should be repeated after 3 to 6 months to confirm a negative result.

Clinicians should obtain a quantitative HCV RNA viral load assay in HIV-infected patients with risk factors for HCV exposure who have a negative HCV ELISA antibody test but unexplained liver disease, including increased serum liver enzymes. (AII)

Positive HCV ELISA screening results require confirmation by viral gene amplification techniques that are used to definitively diagnose HCV infection. HCV RNA is usually detectable within 1 to 2 weeks after exposure to the virus.

In chronically infected patients, HCV RNA may be detectable only intermittently; therefore, a single negative HCV RNA assay does not exclude chronic HCV infection. A follow-up HCV RNA test should be performed after 3 to 6 months to confirm a negative HCV RNA result. A positive result for HCV RNA is confirmation of active infection.

Key Points

  • Delayed or absent HCV seroconversion has been reported in HIV-infected patients[27]; therefore, measurement of HCV RNA may be indicated in individuals with risk factors for HCV exposure who have a negative HCV antibody test but unexplained liver disease or elevated liver enzymes.

  • The level of HCV RNA does not correlate with the severity of liver injury or fibrosis.


Although qualitative tests were previously more sensitive, the limit of detection for most quantitative HCV RNA assay is now sufficiently low to make the quantitative HCV RNA assay the preferred RNA test. Knowledge of the lower limits of detection of available diagnostic tests can enhance assessment of HCV RNA. A transcription-mediated assay is a newer isothermic amplification technology that is similar to a qualitative RNA. Table 1 lists the tests for measuring HCV RNA. Figure 1 provides an algorithm for screening and diagnosis of HCV infection.

Table 1. Available Tests for Measuring HCV RNA

Type of Test a Method (Manufacturer) Dynamic Range b FDA Approval Status
VERSANT HCV RNA 3.0 bDNA (Siemens) 615 to 7.7 × 106 IU/mL c Approved
COBAS AmpliPrep/
COBAS TaqMan HCV Test
Real-time RT-PCR (Roche) 43 to 6.90 × 107 Approved
RealTime HCV Real-time RT-PCR (Abbott) 12 to 1 × 108 IU/mL Submitted
COBAS Amplicor HCV Monitor RT-PCR (Roche) 600 to 5 × 105 IU/mL d Approved
Amplicor HCV Monitor Test, v2.0 RT-PCR (Roche) 600 to 8.5 × 105 IU/mL d Approved
ASR, analyte-specific reagent; bDNA, branched chain DNA; PCR, polymerase chain reaction; qPCR, quantitative PCR; RT, reverse transcription.
a Only quantitative tests are shown because qualitative tests are no longer indicated for clinical use.
b Results may vary at the lower limit of detection depending on the laboratory performing the test.
c Siemens reports results in both IUs and copies/mL.
d According to Conformité Européenne (CE) marking.

Figure 1.

Hepatitis C Virus Testing Algorithm for HIV-Infected Patients * HCV genotypic testing may not be necessary for patients in whom HCV treatment is contraindicated due to nonmodifiable contraindications, such as hypersensitivity to either interferon or ribavirin, hemoglobinopathies (eg, thalassemia major and sickle cell anemia), unstable angina or unstable cardiac arrhythmias, and hepatic decompensation. † Some contraindications would not prevent anti-HCV therapy after they are appropriately addressed (see Table 2). ‡ The medical evaluation for treatment should be performed in consultation with a clinician experienced in the treatment of HCV or a hepatologist (also see Figure 2).

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