Table 3.
Serum tests of hepatic fibrosis and potential confounding factors
| Serum tests | Components | Test performance | Potential confounding factors |
|---|---|---|---|
| AST/ALT ratio | AST, ALT | AUROC 0.66–0.74, Sn 40%, Sp 80% for F3 | Poor performance in patients aged ≤ 35 years |
| AST-to-platelet ratio index (APRI) | AST, platelet | AUROC 0.74, Sn 65%, Sp 72% for F3 |
Platelets may decrease in immune thrombocytopenia purpura and bone marrow diseases Platelets may increase in blood loss or myeloproliferative disease |
| Fibrosis-4 index | Age, AST, ALT, platelet | AUROC 0.80, Sn 65%, Sp 97% for F3 |
Poor performance in patients aged ≤ 35 years Low specificity in patients aged ≥ 65 years Platelets may decrease in immune thrombocytopenia purpura and bone marrow diseases Platelets may increase in blood loss or myeloproliferative disease |
| NAFLD fibrosis score | Age, BMI, impaired fasting glucose or diabetes, AST, ALT, platelet, albumin | AUROC 0.75–0.82, Sn 73–82%, Sp 96–98% for F3 |
Poor performance in patients aged ≤ 35 years Low specificity in patients aged ≥ 65 years Platelets may decrease in immune thrombocytopenia purpura and bone marrow diseases Platelets may increase in blood loss or myeloproliferative disease Albumin may decrease in chronic illnesses, malnutrition, nephrotic syndrome and protein-losing enteropathy Ethnicity |
| BARD score | AST, ALT, BMI, diabetes | AUROC 0.69–0.81, Sn 62%, Sp 66% for F3 | BARD score appears to be less accurate in Japanese and Chinese patients, possibly due to different fat distribution at the same BMI |
| FibroMeter NAFLD | Body weight, prothrombin index, ALT, AST, ferritin, fasting glucose | AUROC 0.76, Sn 22%, Sp 97% for F2; AUROC 0.77, Sn 27%, Sp 95% for F3 |
Prothrombin index affected by anti-coagulants Ferritin is an acute phase protein Glucose is affected by anti-diabetic treatment |
| Enhanced liver fibrosis panel | PIIINP, hyaluronic acid, TIMP1 | AUROC 0.92, Sn 88%, Sp 81% for F1; AUROC 0.98, Sn 94%, Sp 93% for F2; AUROC 0.99, Sn 100%, Sp 98% for F3 |
PIIINP is increased in other fibrotic diseases or bone fracture TIMP1 is increased in cancer and inflammation |
| FibroTest | GGT, total bilirubin, alpha-2-macroglobulin, apolipoprotein A1, haptoglobin | Non-binary AUROC for fibrosis 0.88 |
Haptoglobin affected by hemolysis Bilirubin affected by hemolysis, biliary pathology and Gilbert syndrome GGT affected by alcohol consumption |
ALT alanine aminotransferase, AST aspartate aminotransferase, AUROC area under the receiver-operating characteristics curve, BMI body mass index, GGT gamma-glutamyl transpeptidase, NAFLD nonalcoholic fatty liver disease, PIIINP procollagen III amino-terminal peptide, Sn sensitivity, Sp specificity, TIMP1 tissue inhibitor of metalloproteinases 1