Non-invasive assessment of liver graft fibrosis by transient elastography after liver transplantation.

BACKGROUND: Liver stiffness measurement (LSM) by transient elastography (TE) (FibroScan) is a validated method of quantifying liver fibrosis in non-transplanted patients with hepatitis C virus (HCV). It could be useful in follow-up after liver transplantation (LT). The aim of this study was to assess the diagnostic accuracy of LSM in evaluating liver fibrosis after LT in patients with and without recurrent HCV. PATIENTS AND METHODS: Forty-three patients (mean age 57.6 ± 9.9 years), 28 (65.1%) HCV-positive patients and 15 (34.9%) HCV-negative patients underwent gold standard liver biopsy and TE 55.8 ± 4.9 months after transplantation. Liver fibrosis was scored on biopsy specimens according to METAVIR (F0-F4). Accuracy of TE and optimal stiffness cut-off values for fibrosis staging were determined by a receiver-operating characteristics (ROC) curve analysis.
RESULTS: Median stiffness values were significantly different for METAVIR score less than 2 (5.8 kPa) vs. METAVIR score greater to equal to 2 (9.6 kPa) (P<0.001). The area under the ROC curve was 0.83 for METAVIR score greater to equal to 2 (95%CI: 0.71-0.95). The optimal stiffness cut-off value was 7 kPa for METAVIR scores greater to equal to 2. The results were similar whether the patients had recurrent HCV infection or not.
CONCLUSIONS: These results indicate that transient elastography accurately identifies LT recipients with significant fibrosis, irrespective of HCV status. It is a promising non-invasive tool to assess graft fibrosis progression after LT in patients with HCV recurrence, as well as for screening of late graft fibrosis of other etiologies. Transient elastography could reduce the use of invasive protocol biopsies.