Vibration-controlled Transient Elastography for Assessment of Liver Fibrosis at a USA Academic Medical Center

Abstract

Background and aims: Vibration-controlled transient elastography (VCTE) is a noninvasive tool that uses liver stiffness measurement (LSM) to assess fibrosis. Since real-life data during everyday clinical practice in the USA are lacking, we describe the patterns of use and diagnostic performance of VCTE in patients at an academic medical center in New York City.

Methods: Patients who received VCTE scans were included if liver biopsy was performed within 1 year. Diagnostic performance of VCTE in differentiating dichotomized fibrosis stages was assessed via area under the receiver operating characteristics (AUROC). Fibrosis stage determined from VCTE LSM was compared to liver biopsy.

Results: Of 109 patients, 49 had nonalcoholic fatty liver disease, 16 chronic hepatitis C, 15 congestive hepatopathy, and 22 at least two etiologies. AUROC was 0.90 for differentiating cirrhosis (stage 4) with a positive predictive value (PPV) range of 0.28 to 0.45 and negative predictive value range of 0.96 to 0.98. For 31 (32%) patients, VCTE fibrosis stage was at least two stages higher than liver biopsy fibrosis stage. Thirteen of thirty-five patients considered to have cirrhosis by VCTE had stage 0 to 2 and 12 stage 3 fibrosis on liver biopsy.

Conclusions: VCTE has reasonable diagnostic accuracy and is reliable at ruling out cirrhosis. However, because of its low PPV, caution must be exercised when used to diagnose cirrhosis, as misdiagnosis can lead to unnecessary health care interventions. In routine practice, VTCE is also sometimes performed for disease etiologies for which it has not been robustly validated.

Keywords: Chronic liver disease; Cirrhosis; Hepatitis; Liver histopathology; Nonalcoholic fatty liver disease.

Fig. 1. Study entry flow chart.

Fig. 2. LSM distribution by each liver biopsy fibrosis stage represented by boxplot.

The ends of each box visualize first and third quartile of LSM, whereas the solid line in the middle represents median LSM. Diamonds illustrate outlier LSM values for each fibrosis stage. LSM, liver stiffness measurement.

Fig. 3. Representative cases in which fibrosis stage determined by VCTE LSM significantly overstated histopathological fibrosis on liver biopsy.

Representative photomicrographs are liver sections stained with Masson’s trichrome. LSM, liver stiffness measurement; NAFLD, nonalcoholic fatty liver disease; VCTE, vibration-controlled transient elastography.