Table 1.
Laboratory Tests Used in the Treatment Decision Process for Hepatitis C Virus Infection
| Test | Purpose |
|---|---|
| HCV viral load | Predicts treatment response; does not predict disease severity |
| HCV genotype/subtype | Predicts treatment response; critical to choose correct treatment regimen |
| Hepatitis B surface antigen | Positive result indicates HBV coinfection |
| Hepatitis B surface antibody | Demonstrates protection against HBV and indicates need for vaccination |
| Hepatitis A virus antibody | Demonstrates protection against hepatitis A and indicates need for vaccination |
| Hepatic profile | ALT and AST indicate degree of liver injury present; bilirubin and alkaline phosphatase suggest presence of cholestatic liver processes |
| Complete blood cell count with differential | Provides baseline data before treatment with marrow-suppressive agents |
| Renal profile | Creatinine and creatinine clearance needed to determine treatment candidacy and need for adjustment of dose of some medications |
| Thyrotropin | Marker of thyroid disease that may need to be addressed before or during HCV therapy |
| Autoimmune markers ANA, ASMA (anti-actin antibody), AMA | May indicate presence of underlying comorbid processes that can affect liver; titers >1:80 suggest need to evaluate liver biopsy before treatment initiation |
| α1-Antitrypsin | Protein made by liver; low levels may indicate presence of 1 or 2 alleles for gene polymorphism associated with chronic liver injury |
| Iron saturation | Iron/total iron–binding capacity; levels >50% may suggest presence of genetic hemochromatosis |
| Ceruloplasmin | Copper transport protein; low levels may indicate presence of Wilson's disease (rare) |
| IL28B genotype | Predicts response to HCV treatment |
Abbreviations: ALT, alanine aminotransferase; AMA, antimitochondrial antibody; ANA, antinuclear antibody; ASMA, anti-smooth muscle antibody; AST, aspartate aminotransferase; HBV, hepatitis B virus; HCV, hepatitis C virus.