Coinfection with HBV or HIV is more common in people with HCV infection than in the general population. Testing for HBV and HIV should be performed before starting treatment. However, waiting for the results of HBV and HIV testing should not preclude starting DAA therapy, especially in marginalised individuals who may become lost to follow-up. If testing for HBV and HIV cannot be performed before starting DAA therapy, especially in high-prevalence clinics where people are being screened for HCV using point-of-care tests, HBV and HIV testing should be performed within 4 weeks of starting DAAs. HBV serology should include HBsAg, anti-HBc and anti-HBs (all three tests for HBV may be requested if the clinical notes indicate acute or chronic hepatitis).
It is also important to consider whether another liver disease is present, as this increases the risk of cirrhosis and will need ongoing management after viral eradication. Common comorbidities include excessive alcohol consumption, diabetes, obesity and non-alcoholic fatty liver disease. It is therefore important to perform a targeted assessment in all patients, including calculation of body mass index and measurement of blood pressure, waist circumference, fasting glucose level and lipid levels, as well as HBV and HIV serology. All people with chronic HCV infection should be vaccinated against hepatitis A virus (HAV) and HBV if seronegative.
Testing for other causes of liver disease, including haemochromatosis, autoimmune hepatitis, primary biliary cholangitis, Wilson disease and alpha-1-antitrypsin deficiency, can be reserved for individuals whose liver function test results do not normalise once HCV infection has been cured, or in whom there is a high index of clinical suspicion.