New reliability criteria for transient elastography increase the number of accurate measurements for screening of cirrhosis and portal hypertension

Background & aims: Transient elastography (TE) can non-invasively diagnose cirrhosis and portal hypertension (PHT). New TE reliability criteria suggest classifying measurements as very reliable (IQR/M < 0.1), reliable (IQR<0.3 or >0.3, if TE < 7.1 kPa) and poorly reliable (IQR/M > 0.3, if TE > 7.1 kPa). Compare traditional (reliable: success rate >60% + IQR/M ≤ 0.30) and new TE quality criteria (accurate: very reliable + reliable) regarding their diagnostic accuracy for cirrhosis and PHT and to identify potential confounders (age, aetiology, necroinflammatory activity, steatosis, siderosis, cholestasis, aminotransferases) of TE performance.

Methods: Patients undergoing simultaneous measurements of TE, portal pressure (hepatic venous pressure gradient, HVPG) and liver biopsy were analysed.

Results: Among 226 patients (48.7 ± 13.1 years, 74.7% male, 75.7% viral aetiology, 57% F3/F4), traditional TE quality criteria identified 71.6% reliable measurements, while new criteria yielded in 83.2% accurate results. Reliable TE values according to both criteria significantly correlated with fibrosis stage (r = 0.648 vs. r = 0.636) and HVPG (r = 0.836 vs. r = 0.846). Diagnostic accuracy for cirrhosis (cut-off >14.5 kPa) was 76.5% (AUC: 0.863) and 75.0% (AUC: 0.852) for traditional and new TE criteria, respectively, while for predicting HVPG ≥ 10 mmHg (>16.1 kPa), the accuracies were 88.9% (AUC: 0.957) and 89.8% (AUC: 0.962). New TE criteria allowed a better discrimination of reliable and non-reliable results for prediction of fibrosis and CSPH. Only aetiology and aminotransferases were independent confounders of the correlation of TE and fibrosis stage, while no confounder affected the correlation of TE and HVPG.

Conclusions: New reliability criteria for TE measurements increase the number of patients with accurate measurements without affecting diagnostic performance for detecting cirrhosis and portal hypertension. Aetiology of liver disease and aminotransferases should be considered when assessing liver fibrosis by TE.