 |
|
|
| |
Validation of the new 2021 EASL algorithm for the non-invasive diagnosis of advanced liver fibrosis in non-alcoholic fatty liver disease
EASL Algorithm Accurate for Advanced Fibrosis in NAFLD
|
| |
| |
EASL International Liver Congress 2022, London, June 22-26, 2022
Mark Mascolini
An EASL-proposed sequential algorithm for noninvasive diagnosis of advanced liver fibrosis in people with nonalcoholic fatty liver disease (NAFLD) had high accuracy in an analysis of 1051 NAFLD patients with liver biopsy [1]. Simulation indicated that the algorithm can be used in primary care and for people with diabetes.
In its 2021 guidelines EASL (the European Association for the Study of the Liver) proposed an algorithm for diagnosing advanced liver fibrosis in people with NAFLD. The algorithm sequentially considers FIB4, vibration-controlled transient elastography (VCTE), and-in an innovative step-a patented serum test.
The algorithm specifies that FIB4 below 1.30 indicates very low risk of advanced fibrosis and no need for referral. Higher FIB4 calls for VCTE to measure liver stiffness. VCTE below 8 kPa indicates very low risk of advanced fibrosis and no need for further testing. VCTE above 8 kPa indicates a need for referral to a liver specialist to confirm advanced fibrosis with a patented serum test-ELF, Fibrotest, or FibroMeter. Discordant results with VCTE and a serum test indicate liver biopsy should be considered.
Because the EASL algorithm remained unvalidated in clinical practice, French researchers undertook such an evaluation in 1051 patients with biopsy-confirmed NAFLD. The primary outcome was advanced fibrosis (F3-F4 NASH CRN). Study participants came from Angers, Bordeaux, and Grenoble. Everyone had blood test results to calculate FIB4, VCTE, FibroMeter, and Fibrotest; 396 people had ELF results.
Median age of the study group stood at 58.1 and median body mass index at 31.2 kg/m2 (in the obese range), While 59.5% of participants were men, 50% had diabetes, and 40% had advanced fibrosis.
Test accuracy proved high for each individual test and was similar in the entire cohort and the ELF subset, listed here: FIB4 area under the receiver operating characteristic curve (AUROC) 0.768, VCTE AUROC 0.855, Fibrotest AUROC 0.770, FibroMeter AUROC 0.837, and ELF AUROC 0.869. FibroMeter and ELF results were similar and better than results with FIB4 or Fibrotest.
In the entire cohort FIB4 had a sensitivity of 81%, which the researchers called acceptable. But positive predictive value with FIB4 reached only 58%, which means an additional test should be used on people with a positive FIB4. VCTE had an excellent sensitivity of 88% in this cohort, which allowed the researchers to exclude 33% of people without advanced fibrosis.
VCTE positive predictive value stood at a meager 62% but reached 73% with sequential use of FIB4 and VCTE. Positive predictive value inched up to 77% with a patented serum test added to VCTE. Discordant VCTE and serum test results identified a subgroup with a very low positive predictive value of 35% to 47% (depending on the serum test). That result validates use of liver biopsy in people with discordant VCTE-serum test results, as the EASL algorithm stipulates.
For the whole cohort, the sequence FIB4, VCTE, and FibroMeter had a diagnostic accuracy of 81.4%, sensitivity of 71.3%, specificity of 88.0%, and need for biopsy in only 6.8%. For the sequence FIB4, VCTE, and Fibrotest, diagnostic accuracy stood at 82.8%, sensitivity at 71.3%, and specificity at 90.2%, with 12.7% requiring biopsy. Results proved similar in the ELF subset. For example with the sequence FIB4, VCTE, and ELF, diagnostic accuracy was 87.4%, sensitivity 73.5%, specificity 94.3%, and need for biopsy 11.9%.
The researchers concluded that their findings validate EASL advice to use FIB4, VCTE, and a patented serum test to diagnose advanced liver fibrosis in people with NAFLD. Diagnostic accuracy is similar with the three serum tests analyzed-FibroMeter, Fibrotest, and ELF. Simulation showed that this algorithm is appropriate for primary care and for diabetes clinics.
Reference
1. Canivet CM, Lannes A, Costentin C, et al Validation of the new 2021 EASL algorithm for the non-invasive diagnosis of advanced liver fibrosis in non-alcoholic fatty liver disease. ASL International Liver Congress 2022, London, June 22-26, 2 022. Abstract OS099.
|
| |
|
|
|
|
|
