Elastography for the diagnosis of severity of fibrosis in chronic liver disease: A meta-analysis of diagnostic accuracy

• Published in: Journal of hepatology 2011-04, Vol.54 (4), p.650-659
• Main Authors: Tsochatzis, E.A, Gurusamy, K.S, Ntaoula, S, Cholongitas, E, Davidson, B.R, Burroughs, A.K
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biopsy; Chronic Disease; Elasticity Imaging Techniques; Gastroenterology and Hepatology; Gastroenterology. Liver. Pancreas. Abdomen; Liver - pathology; Liver Cirrhosis - diagnosis; Liver Cirrhosis - pathology; Liver Diseases - diagnosis; Liver Diseases - pathology; Medical sciences; Severity of Illness Index
• ISSN: 0168-8278; 1600-0641
• DOI: 10.1016/j.jhep.2010.07.033

Background & Aims Transient elastography is a non-invasive method, for the assessment of hepatic fibrosis, developed as an alternative to liver biopsy. We studied the performance of elastography for diagnosis of fibrosis using meta-analysis. Methods MEDLINE, EMBASE, SCI, Cochrane Library, conference abstracts books, and article references were searched. We included studies using biopsy as a reference standard, with the data necessary to calculate the true and false positive, true and false negative diagnostic results of elastography for a fibrosis stage, and with a 3-month maximum interval between tests. The quality of the studies was rated with the QUADAS tool. Results We identified 40 eligible studies. Summary sensitivity and specificity was 0.79 (95% CI 0.74–0.82) and 0.78 (95% CI 0.72–0.83) for F2 stage and 0.83 (95% CI 0.79–0.86) and 0.89 (95% CI 0.87–0.91) for cirrhosis. After an elastography result at/over the threshold value for F2 or cirrhosis (“positive” result), the corresponding post-test probability for their presence (if pre-test probability was 50%) was 78%, and 88% respectively, while, if values were below these thresholds (“negative” result), the post-test probability was 21% and 16%, respectively. No optimal stiffness cut-offs for individual fibrosis stages were validated in independent cohorts and cut-offs had a wide range and overlap within and between stages. Conclusions Elastography theoretically has good sensitivity and specificity for cirrhosis (and less for lesser degrees of fibrosis); however, it should be cautiously applied to everyday clinical practice because there is no validation of the stiffness cut-offs for the various stages. Such validation is required before elastography is considered sufficiently accurate for non-invasive staging of fibrosis.