Improved diagnostic accuracy of blood tests for severe fibrosis and cirrhosis in chronic hepatitis C.
OBJECTIVE
Blood tests are usually designed to identify significant fibrosis. We evaluated their diagnostic accuracy, and how to increase it, for the clinically important targets of severe fibrosis and cirrhosis.


METHODS
The accuracy for severe fibrosis or cirrhosis of four blood tests was evaluated based on Metavir staging in 1056 patients with chronic hepatitis C recruited in five independent hospitals.


RESULTS
Using original scores, an original diagnostic target (significant fibrosis) and best diagnostic cutoff, the correct classification rates in severe fibrosis and cirrhosis stages were, respectively: FibroMeter: 90.1, 100%, Fibrotest: 78.2, 95.1%, Hepascore: 73.8, 94.9%, aspartate aminotransferase to platelet ratio index (APRI): 71.4, 88.0% (P<0.003, P=0.004, respectively, between tests). The corresponding area under the receiver operating characteristics were FibroMeter: 0.885, 0.907, Fibrotest: 0.837, 0.882, Hepascore: 0.834, 0.896, APRI: 0.822, 0.841 (P<0.003, respectively). Observed 100% negative predictive values for severe fibrosis and cirrhosis were, respectively, FibroMeter: 15.4, 47.5%, Fibrotest: 3.6, 31.9%, Hepascore: 0.3, 24.6%, APRI: 1.4, 5.3% of patients (P<0.003, respectively, between tests). By calculating a specific test for cirrhosis, including the FibroMeter markers, the correct classification (93.0%) was significantly higher for the cirrhosis diagnosis compared with the original FibroMeter (90.9%, P=0.005). This specific test provided a 100% positive predictive value for cirrhosis diagnosis versus 88% for original FibroMeter.


CONCLUSIONS
Using the most accurate original test, cirrhosis can be excluded in 47.5% of patients and is correctly diagnosed, as significant fibrosis, in 100% of patients. A specific test for cirrhosis provides a significant gain in diagnostic accuracy to 93% and in positive predictive value to 100% compared with the original test.
Boursier
Jérôme
J
Hepatogastroenterology Department, CHU, Angers, France.
Bacq
Yannick
Y
Halfon
Philippe
P
Leroy
Vincent
V
de Ledinghen
Victor
V
de Muret
Anne
A
Bourlière
Marc
M
Sturm
Nathalie
N
Foucher
Juliette
J
Oberti
Frédéric
F
Rousselet
Marie Christine
MC
Calès
Paul
P
D000328:Adult; D015415:Biomarkers / Q000097:blood*; D001707:Biopsy, Needle; D005260:Female; D019698:Hepatitis C, Chronic / Q000150:complications*; D006801:Humans; D008099:Liver / Q000473:pathology*; D008103:Liver Cirrhosis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012680:Sensitivity and Specificity
D015415:Biomarkers