Predicting treatment outcome following 24 weeks peginterferon α-2a/ribavirin therapy in patients infected with HCV genotype 1: Utility of HCV-RNA at day 0, day 22, day 29, and week 6

✍ Scribed by Esther Lukasiewicz; Kristoffer Hellstrand; Johan Westin; Carlo Ferrari; Avidan U. Neumann; Jean-michel Pawlotsky; Solko W. Schalm; Stefan Zeuzem; Bart J. Veldt; Bettina E. Hansen; Elke Verhey-hart; Martin Lagging

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 68 KB
• Volume: 45
• Category: Article
• ISSN: 0270-9139
• DOI: 10.1002/hep.21505

✦ Synopsis

We sought to validate FIB-4 using data retrospectively collected from treatment-naive HIV/HCV patients. The original model was adapted in order to use AST and ALT levels expressed as times the upper limit of normality (ϫULN), as follows: (age [yr] ϫ AST [ϫULN]) ϫ 10/((PLT [10 9 /l]) ϫ (ALT [ϫULN]) 1/2 ). We evaluated 111 patients (males, 73%; mean age, 40.2 Ϯ 7.8 years). Mean CD4ϩ cell count was 431 Ϯ 225 cells/ml and 58% of patients had undetectable HIV viral load under antiretroviral therapy. All patients showed HCV viremia and underwent liver biopsy, irrespective of ALT levels. A single pathologist analyzed all liver biopsy slides using the METAVIR group scoring system.

Advanced liver fibrosis, defined by the presence of F3 or F4 META-VIR stages, was observed in 28 patients (25%). To discriminate these subjects, the area under the receiver operating characteristic curve (ROC) of FIB-4 was 0.846 Ϯ 0.046. Based on the ROC, 2 cutoffs were chosen: Ͻ2.6 and Ն5.0. Among patients with scores Ͻ2.6 or Ն5.0, concordant results were found in 88% (65/74). If biopsy indication was based only on FIB-4 results and restricted to scores in the intermediate range (Ն2.6 and Ͻ5.0), 67% of liver biopsies could have been avoided.

Overall, our results are similar to the data presented by Sterling et al. (Table 1). In fact, even higher sensitivities and positive and negative predictive values were achieved. The use of different histological scoring systems (i.e., METAVIR versus Ishak score) and the evaluation of our cohort by a single pathologist could be responsible for these differences. Nevertheless, in both studies the FIB-4 index could reliably predict the severity of liver fibrosis in about 70% of patients with HIV/HCV co-infection, possibly avoiding the requirement for a liver biopsy in those patients.

Finally, we would like to suggest the use of AST and ALT levels as times the upper limit of normality in the calculation of FIB-4, which can expand its applicability to populations with different reference ranges for aminotransferases.