How should I interpret positive Hepatitis C antibody test results in my patients?

A positive hepatitis C antibody test indicates that a patient has been exposed to the hepatitis C virus (HCV) at some point, but it does not confirm current active infection. To interpret a positive antibody result, it is essential to perform a confirmatory test for HCV RNA (viral load) to determine if the patient has an active infection or if the infection has resolved spontaneously or after treatment ¹.

If HCV RNA is detected (RNA positive), this confirms current active infection, and the patient should be referred urgently to specialist care for further assessment and management, including baseline investigations and consideration of antiviral treatment ¹. If HCV RNA is not detected (RNA negative), this suggests past exposure with resolved infection or false-positive antibody test, and no active infection is present; however, clinical context and risk factors should be considered ¹.

In cases where acute HCV infection is suspected (positive antibody with clinical features of acute hepatitis or recent exposure), immediate specialist advice or same-day assessment is recommended to monitor for spontaneous viral clearance over the initial 3 months ¹.

While awaiting specialist assessment, baseline blood tests including liver function tests, full blood count, clotting studies, and screening for co-infections (hepatitis A, B, HIV) should be arranged, alongside advice on reducing transmission risk and disease progression ¹.

Laboratories in the UK are expected to automatically perform HCV RNA testing on samples positive for hepatitis C antibody to facilitate timely diagnosis and management ².

Overall, a positive hepatitis C antibody test is a marker of exposure, not definitive of active infection, and must be followed by HCV RNA testing to guide clinical decisions ¹; (Contreras et al., 2012).