Research ArticleElastography for the diagnosis of severity of fibrosis in chronic liver disease: A meta-analysis of diagnostic accuracy
Introduction
Liver fibrosis represents the final common outcome of chronic liver injury and is often progressive, eventually evolving into cirrhosis [1]. Cirrhosis is the severest form of fibrosis with the worst clinical outcomes.
Currently, histological examination of a liver biopsy specimen is the reference standard for the diagnosis, staging, and monitoring of liver fibrosis [2]. However, it is invasive and can lead to fatal bleeding [2].
Transient elastography is a non-invasive method of quantifying fibrosis developed as an alternative to liver biopsy. Ultrasound elastography analyses ultrasound frequency waves which are related to the elasticity (deforming capacity) of the liver. It is simple, highly reproducible, and can be completed in 10 min in an outpatient setting with no significant expertise [3]. Magnetic resonance elastography involves measuring the elasticity of liver tissues using complex algorithms [4]. An increasing number of studies have evaluated the accuracy of elastography in the staging of fibrosis and compared it to liver biopsy.
In the present study, we used meta-analysis to assess the performance of elastography in the diagnosis of severity of liver fibrosis using liver biopsy as the reference standard.
Section snippets
Criteria for the selection of studies
We included full papers and abstracts, without language restrictions that (1) evaluated elastography in the diagnosis of severity of liver fibrosis or monitoring thereof, using liver biopsy as the reference standard, and (2) reported on data necessary to calculate the true positive false positive, true negative and false negative diagnostic results of elastography for the diagnosis of a fibrosis stage based on a defined cut-off point for liver stiffness. If such data were unavailable, the
Description of studies
We identified 1289 references. The reference flow is shown in Fig. 1. The inclusion criteria were fulfilled in 43 studies (35 full papers, eight abstracts) [3], [4], [14], [15], [16], [17], [18], [19], [20], [21], [22], [23], [24], [25], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35], [36], [37], [38], [39], [40], [41], [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54]. From these, three studies were excluded, as they evaluated magnetic resonance
Discussion
In our meta-analysis, we evaluated the diagnostic accuracy of transient elastography in the staging of liver fibrosis, as reported in 40 studies. Although three meta-analyses have already been published on this subject [57], [58], [59], our meta-analysis evaluates 29 different studies compared to these, with an overlap of 25% or less. Moreover, none of these meta-analyses has used the optimal statistical methods of combining the studies, i.e. HSROC or bivariate model [8]. Furthermore, none has
Conflict of interest
The authors who have taken part in this study declare that they do not have anything to disclose regarding funding or conflict of interest with respect to this manuscript.
Acknowledgements
E.A. Tsochatzis has received an educational grant from the Hellenic Association for the Study of the Liver.
References (65)
- et al.
Magnetic resonance elastography for the noninvasive staging of liver fibrosis
Gastroenterology
(2008) - et al.
The diagnostic odds ratio: a single indicator of test performance
J Clin Epidemiol
(2003) - et al.
The performance of tests of publication bias and other sample size effects in systematic reviews of diagnostic test accuracy was assessed
J Clin Epidemiol
(2005) - et al.
Prospective comparison of transient elastography, fibrotest, APRI, and liver biopsy for the assessment of fibrosis in chronic hepatitis C
Gastroenterology
(2005) - et al.
Early detection in routine clinical practice of cirrhosis and oesophageal varices in chronic hepatitis C: comparison of transient elastography (FibroScan) with standard laboratory tests and non-invasive scores
J Hepatol
(2009) - et al.
Assessment of liver fibrosis in transplant recipients with recurrent HCV infection: usefulness of transient elastography
Digest Liver Dis
(2009) - et al.
J Hepatol
(2009) - et al.
Features associated with success rate and performance of fibroscan measurements for the diagnosis of cirrhosis in HCV patients: A prospective study of 935 patients
J Hepatol
(2007) - et al.
J Hepatol
(2009) - et al.
Assessment of liver fibrosis using transient elastography in patients with alcoholic liver disease
Journal of Hepatology
(2008)