We recommend patients who have repeated high-risk exposures but persistently normal transaminases are screened with anti-HCV and HCV-PCR, or HCV-PCR alone if previously successfully treated for or spontaneously have cleared infection and are HCV antibody positive, at 3–6-monthly intervals. Proportion of patients with acute HCV who had an HCV-PCR assay as the screening test Proportion of patients with repeated high-risk exposure who had HCV tests (antibody and PCR) at least twice a year
Proportion of all adults with HIV infection who had an HCV test within 3 months of HIV diagnosis Studies have shown that in HCV/HIV the first test to become positive is the HCV-PCR, often within 1 month [30–31]. It is difficult to be precise about time of exposure to infection but the HCV-PCR learn more is positive a median of 3 months (range 1–9 months) after the last negative PCR test. Transaminases are abnormal in 78% of patients at the time of first positive PCR, rising to 88% 3 months selleck chemical later. The combined HCV antigen/antibody test is more sensitive than the antibody
test alone in detecting acute infection and is being used in many centres for screening patients with risk factors for infection. It is not as sensitive as the PCR assay and is positive in 52% of patients at the time of the first PCR being positive [31]. HCV antibody tests
are the least sensitive for acute infection, being positive in 20–25% at the time of the first PCR positive test. On average, HCV Ab becomes positive 3–7 months after the first positive PCR test but at 9 months 10% of patients remain HCV Ab negative which reduces to 5% at 1 year. Individuals with HCV infection may thus have a negative antibody test. Individuals with unexplained abnormal transaminases, especially if they are in a risk group for HCV exposure, should have an HCV-PCR assay in order to exclude acute HCV infection. In MSM and IDUs who have cleared HCV infection either spontaneously or through treatment, the rate of HCV reinfection is up to 10-times higher than in previously uninfected patients [32–36]. In the EuroSIDA study of HIV-infected patients, 20% of ZD1839 MSM and IDUs who are cured of HCV will be re-infected subsequently [37–38]. Therefore it is important to monitor previously infected individuals frequently, with HCV-PCR being the only reliable assay [35–38]. In HIV-infected men who have sex with men, there is an appreciable rate of HCV infection (6/1000 patient-years in one study [8]), and given the benefits of HCV being diagnosed early, all HIV-infected patients should be tested annually and more frequently if transaminases are raised without obvious cause [30–31,34].