Accurate evaluation of liver fibrosis is essential for predicting the prognosis and assessing treatment responses in chronic liver diseases. Liver biopsy is the reference method for evaluating fibrosis but is limited by its invasive nature. Various non-invasive methods to measure liver fibrosis have been developed and reliably used for most chronic liver diseases. Liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE) is a fast, simple, and widely accepted method to assess the degree of liver fibrosis. Its performance has been intensively verified for metabolic dysfunction-associated steatotic liver diseases and viral hepatitis [1].
Liver fibrosis is a critical pathologic finding to predict the prognosis and evaluate treatment response, also in autoimmune liver diseases (AILD), including primary biliary cholangitis (PBC), autoimmune hepatitis (AIH), and primary sclerosing cholangitis (PSC) [2-4]. LSM has been proposed as a clinically relevant surrogate marker in therapeutic trials and for guiding treatment decision-making in PBC [5]. Although several studies have examined the diagnostic accuracy of VCTE for AILD, their statistical power is often limited by small sample sizes. In this regard, a meta-analysis by An et al. [6] provides additional evidence on the performance of VCTE in AILD.
This study showed that VCTE has excellent diagnostic performance for PBC, as demonstrated by the summary area under the curve (sAUC) >0.87 and diagnostic odds ratio (DOR) >34. However, the range of cut-off values for different stages of fibrosis (F2, F3, F4) is too wide and sometimes overlaps, which makes it harder to pinpoint the exact stage of fibrosis. LSM by VCTE can be affected by several factors, including body mass index, cholestasis, inflammation, and treatment status [7]. A study by Koizumi et al. showed exceptionally higher cut-off values compared to other studies [8]. The reason for the higher cut-off values is unclear as this study did not provide detailed information on treatment duration or response.
For AIH, VCTE offers good diagnostic performance with AUROC >0.85 and DOR >20, but, as with PBC, there is significant variability in the cut-off values to discriminate different stages of liver fibrosis, ranging from 12.3–19 kPa for F4 fibrosis. LSM by VCTE was more accurate after six months of immune suppression, as liver inflammation significantly impacts liver stiffness in the first months of AIH treatment.9 Studies analyzed in this meta-analysis appear to include patients with different extents of liver inflammation. Therefore, subgroup analysis by aminotransferase levels can be helpful if feasible.
VCTE has shown good diagnostic performance in PSC, but the studies available are fewer with a smaller patient population, which makes it harder to draw definitive conclusions. Despite this, the data available suggest that VCTE can effectively assess liver fibrosis in PSC patients as well.
In conclusion, An et al. provided more robust evidence that VCTE performs well in discriminating the degree of liver fibrosis in AILD. However, factors such as treatment duration and response, which are likely to influence VCTE, were not thoroughly analyzed due to limited data. Further research is needed to determine the optimal timing for measuring liver stiffness and to understand the effects of treatment duration, treatment response, aminotransferase levels, and alkaline phosphatase levels on VCTE performance in AILD.
PDF Links
PubReader
ePub Link
XML Download
Full text via DOI
Download Citation
Print
