Comparison and validation of simple noninvasive tests for prediction of fibrosis in chronic hepatitis C

Liver biopsy is recommended before antiviral treatment, particularly for patients with hepatitis C virus (HCV) genotype I infection, but it may cause complications and is limited by sampling error. Several non-invasive tests comprising routine laboratory parameters (simple fibrosis tests) have been proposed to predict fibrosis in chronic HCV. The aim of the current study was to validate and compare the diagnostic accuracies of the simple fibrosis tests, aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio (AAR), cirrhosis discriminant score (CDS), age-platelet (AP) index, Pohl score, AST-to-platelet ratio index (APRI), and platelet count per se. Staging was performed in liver biopsy specimens of 194 treatment-naive patients with chronic HCV according to Ishak et al. by two independent pathologists. Receiver operating characteristic curve analysis showed comparable diagnostic accuracies of CDS, AP index, APRI, and platelet count for prediction of significant fibrosis (F3-F6) (area under the ROC curve [AUROC], 0.71, 0.74, 0.80, and 0.71, respectively; pathologist A) and for prediction of cirrhosis (F5-F6) (AUROC, 0.91, 0.91, 0.90, and 0.89, respectively; pathologist A). Diagnostic accuracy of APRI for prediction of significant fibrosis was superior to that of AAR (P <.05). Significant fibrosis was reliably predicted by APRI 2: 1.5 and platelet count < 150 X 10(9)/L in 24% and 22% of the patients, respectively, whereas cirrhosis was reliably excluded by APRI < 2.0 and platelet count >= 150 X 10(9)/L in 85% and 78% of the patients, respectively. In conclusion, simple fibrosis tests may render liver biopsy unnecessary only in a minority of patients with chronic HCV. Improved serum fibrosis markers with greater sensitivity for severe fibrosis or cirrhosis are needed.