Source Department of Internal Medicine, Mayo Clinic, Rochester, MN.
BACKGROUND: Ultrasound-based transient elastography is a promising noninvasive alternative to liver biopsy for detecting hepatic fibrosis due to recurrent hepatitis C (HCV) after liver transplantation (LT). However, its overall test performance in various settings remains unknown.
AIMS: To perform a systematic review and diagnostic accuracy meta-analysis of studies comparing ultrasound-based transient elastography with liver biopsy for detecting hepatic fibrosis due to recurrent HCV infection after LT.
METHODS: Electronic and manual bibliographic searches including scientific abstracts to identify potential studies were performed. Meta-analysis was conducted to generate pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio of individual studies. Extent and reasons for heterogeneity were assessed.
RESULTS: Six studies in full publication were identified for analysis. Five studies were identified that evaluated significant fibrosis. Among these studies the pooled estimates for sensitivity were 83% (95% CI, 77%-88%), specificity 83% (95% CI, 77%-88%), positive likelihood ratio 4.9 (95% CI, 3.4-7.2), negative likelihood ratio 0.17 (95% CI, 0.09-0.35), and diagnostic odds ratio 30.5 (95% CI, 12.8-72.4). For the five studies that assessed, the pooled estimates for sensitivity were 98% (95% confidence interval [CI], 90%-100%), specificity 84% (95% CI, 80%-88%), positive likelihood ratio 7 (95% CI, 2.8-17.3), negative likelihood ratio 0.06 (95% CI, 0.02-0.19), and diagnostic odds ratio 130 (95% CI, 36.5-462.1). Diagnostic threshold (or cut-off value) bias was identified as an important cause of heterogeneity for pooled results in both patient groups.
CONCLUSIONS: 1) Ultrasound-based transient elastography has excellent diagnostic accuracy for identifying cirrhosis due to recurrent HCV infection after LT. 2) The detection of significant fibrosis is more accurate when compared to patients with chronic HCV infection of the native liver.