Diagnostic Accuracy of Transient Elastography for Detecting Liver Fibrosis After Liver Trannsplantation: A Specific Cut-Off Value Is Really Needed?

INTRODUCTION: Liver transplant recipients often perform liver biopsy (LB), specially in the context of potentially recurring diseases, such as hepatitis C infection. However, the LB has risks of complications, despite being the gold standard. Transient elastography (TE) is a noninvasive method comparable to the LB to evaluate liver fibrosis in various settings, but its accuracy among transplant recipients is not fully understood.

OBJECTIVE: To determine the accuracy of TE in liver transplant recipients compared with LB to successfully predict liver fibrosis.

PATIENTS AND METHODS: Patients who underwent liver transplantation at Hospital Israelita Albert Einstein from 2010 to 2012 and presented with LB indication were also subjected to TE at the time of LB. The medium value of ten successful measurements was kept as a representative of the liver stiffness. The definition of cut-off points was made to ensure specificity of ≥90 % for all fibrosis stages (F0-F4).

RESULTS: LB was performed in 267 patients. TE was not analyzed in only 8 (3 %) due to an elevated body mass index. The optimal liver stiffness cut-off value and diagnostic performance were 8.1 kPa for F ≥ 1, 12.3 kPa for F ≥ 2, 15.1 for F ≥ 3, and 16.7 for F = 4 for all patients and were 8.1 kPa for F ≥ 1, 12.3 kPa for F ≥ 2, 16.5 for F ≥ 3, and 17.6 for F = 4 for patients with hepatitis C.

CONCLUSIONS: TE demonstrated good performance in defining cut-off points for fibrosis on liver histology observed in transplant recipients. The TE can be considered an alternative to LB in post-liver transplantation.