Guide to HIV and hepatitis C coinfection
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Testing and monitoring Tests to diagnose HCV Annual HCV testing is routinely recommended in the UK as part of HIV monitoring. This is especially important for anyone who has had another STI and/ or is sexually active or injecting drugs. HCV testing is also recommended if liver enzymes become raised. HCV testing is a two-stage process. 1) The first test is usually an HCV antibody test. A positive result means that you either have had HCV and cleared it or that you still have HCV. A negative result can also mean that you have HCV. This test will not detect acute HCV because it can take 6-24
weeks after infection for HCV antibodies to develop. It is also less effective if your CD4 count is less than 200. 2) An HCV viral load test (RNA) will confirm or rule out chronic infection. The viral load test looks for genetic material of HCV in the same way as an HIV viral load test detects HIV. If you have detectable HCV viral load, it means that you are currently infected with HCV. If your HCV viral load is undetectable, a second test should be done six months later. If two successive test results are undetectable, you have spontaneously cleared HCV. See Table 1 for information about HCV tests.
Table 1: HCV tests and what the results mean for HCV infection Type of Test Diagnosis
Antibody test result
HCV RNA (Viral load test)
ALT: liver enzyme
Prior, cleared HCV Infection
Positive
Undetectable on two tests, performed at least 6 months apart
Acute HCV Infection
Negative; becomes posistive within 6-24 weeks
Detectable within 1-2 weeks, usually very high
May be up to 7 units/L, fluctuate, or be persistently raised May be up to 7-10 times above normal level
Chronic HCV Infection
Positive
Detectable
36
May be persistently normal, fluctuate, or persistently raised November 2013