Skip to main content

Table 4 Review of high risk FibroTest using charts in the reference center (P4)

From: Applicability and precautions of use of liver injury biomarker FibroTest. A reappraisal at 7 years of age

Components of FibroTest with
high risk profile
Number of Tests
Identified
Reviewed
(Traceability)1
Correctly classified Indeterminate Incorrectly classified
    True Positive True Negative   False positive False negative
Haptoglobin        
< = 0.08 g/L 324 214 (66%) 58 (27%) 0 (0%) 42 (20%) 114 (53%)2 0 (0%)
> = 3.20 g/L 0 0 (100%) 0 0 0 0 0
Apolipoprotein A1        
< = 0.56 g/L 25 17 (68%) 15 (88%) 0 0 (0%) 2 (12%)3 0 (0%)
> = 2.50 g/L 57 38 (67%) 1 (3%) 30 (79%) 4 (10%) 0 (0%) 3 (8%)4
Alpha-2 macroglobulin        
< = 0.80 g/L 54 32 (59%) 3 (10%) 24 (75%) 0 (0%) 0 (0%) 5 (15%)5
> = 5.90 g/L 24 24 (100%) 22 (92%) 0 2 (8%) 0 (0%) 0 (0%)
GGT IU/L > = 1140 IU/L 8 6 (75%) 1 (16%) 1 (16%) 2 (33%) 2 (33%)6 0 (0%)
Total Bilirubin, μmol/L > = 50 0 0 (100%) 0 0 0 0 0
Total 491 331 (67%) 100 (30%) 55 (17%) 50 (14%) 118 (36%) 8 (2%)
  1. 1 Inpatients with detailed charts reviewed by 3 experts. (Supplement file S3)
  2. When biopsy was performed (5 years apart) it was taken as a reference; when no biopsy had been performed but an LSM was interpretable it was taken as a reference (advanced fibrosis if greater than 7.1 kPa); when oesophageal varices or ascites were present it was taken as advanced fibrosis; for low hapto, if no reference and a cause of hemolysis was identified FT > = 0.48 was considered false positive. When no reference was present without a clear cause of component error (such as hemolysis for hapto or severe undernutrition for A2M and apoA1, the case was stated to be indeterminate.
  3. 2 Low haptoglobin, already known causes: hemolysis with patent cause: cardiac prosthesis (n = 25), drepanocytosis (n = 13), ribavirin (n = 8), thalassemia (n = 2), autoimmune (n = 2); anahaptoglobinemia (n = 1). Two new possible causes were HIV co-infection (n = 14) and splenectomy (n = 4)
  4. 3 Low ApoA1 already known cause: severe undernutrition (n = 2 total serum proteins < = 50 g/L)
  5. 4 High ApoA1 suspected analytical error or an unknown transient factor as in 2 cases, 2 repeated ApoA1 assays were in normal range
  6. 5 Low A2M already known causes: large ascites (n = 3), severe undernutrition (n = 1 total serum proteins < = 50 g/L); a new possible cause was macrophage activation syndrome (n = 1)
  7. 6 High GGT already known cause: chronic pancreatitis (n = 2)