Hepatitis C: screening, positive serology and tests before treatment

Laboratory tests

• Hepatitis C serology (anti-HCV antibodies)
• Wording to put on the request: "perform HCV RNA as a matter of course if anti-HCV antibodies are positive".
• HCV RNA (as a reflex test if antibodies positive)if neededReflex test recommended when serology is newly positive (grade B) ^[2]; straight away, with the antibodies, if recent infection ^[2] or severe immunosuppression ^[3] is suspected.
• Hepatitis B serology (HBsAg, anti-HBc, anti-HBs)if neededTo be combined according to risk factors ^[3]; the AFEF (French Association for the Study of the Liver) recommends combined HBV, HCV and HIV screening ^[4].
• HIV serologyif neededTo be combined according to risk factors ^[3]; the AFEF (French Association for the Study of the Liver) recommends combined HBV, HCV and HIV screening ^[4].

Laboratory tests (if RNA was not done as a reflex test)

• HCV RNA (quantitative viral load)

12 to 24 weeks later, if RNA is negative

• HCV RNA (repeat)if neededAntibodies positive and RNA negative: a second RNA 12 to 24 weeks later confirms spontaneous clearance (grade A) ^[2].

Fasting laboratory tests

• FBC with platelets
• AST
• ALT
• GGT
• Bilirubin
• Fasting plasma glucose
• Serum creatinine with eGFR (CKD-EPI)
• Hepatitis B serology: HBsAg, anti-HBc, anti-HBs (if not done)
• HIV serology (if not done)
• Hepatitis A serology (IgG)
• FibroTest or FibroMeter (if elastography is not available)if neededFibrosis assessment is mandatory before treatment (grade A): elastometry, FibroTest or FibroMeter ^[2,3]. Reimbursed for this indication, the French laboratory fee schedule (NABM) places them “within specialist care” ^[12].
• Anti-HDV antibodies (if HBsAg positive)if neededHBV co-infection: look for HDV if HBsAg is positive (grade A) ^[2]; the patient then leaves the simplified pathway ^[3].
• Cryoglobulins (if extrahepatic manifestations)if neededCutaneous, neurological, muscular, joint, renal or haematological manifestation suggesting cryoglobulinaemic vasculitis (grade A) ^[2].
• Serum β-hCG (in a woman of childbearing potential)if needednon-French guidelineThe American AASLD-IDSA guide proposes a pregnancy test and information on the risks for women of childbearing potential before any antiviral ^[14]. The French recommendation rules out treatment during pregnancy without providing for this test ^[2,3].
• Liver elastography (FibroScan) and ECG before treatment (not a laboratory test).

Child, between 2 and 6 months

• Child's HCV RNA (if follow-up to 18 months is uncertain)if needednon-French guidelineIn the United States (CDC 2023, AASLD-IDSA), every exposed infant has an RNA test between 2 and 6 months, to limit the number of children never tested and to give families answers sooner; an undetectable result removes the need for follow-up ^[15,16]. The French recommendation and the EASL set screening from 18 months, without addressing early RNA ^[2,8]. The NABM provides for the procedure for diagnosis in a child born to an infected mother, when serology is positive ^[12].

Child, from 18 months

• Child's hepatitis C serology (HCV RNA if positive)