Prospective comparison of transient elastography, MRI and serum scores for grading steatosis and detecting non-alcoholic steatohepatitis in bariatric surgery candidates

Philippe Garteiser; Laurent Castera; Muriel Coupaye; Sabrina Doblas; Daniela Calabrese; Marco Dioguardi Burgio; Séverine Ledoux; Pierre Bedossa; Marina Esposito-Farèse; Simon Msika; Bernard E Van Beers; Pauline Jouët

doi:10.1016/j.jhepr.2021.100381

Prospective comparison of transient elastography, MRI and serum scores for grading steatosis and detecting non-alcoholic steatohepatitis in bariatric surgery candidates

JHEP Rep. 2021 Sep 30;3(6):100381. doi: 10.1016/j.jhepr.2021.100381. eCollection 2021 Dec.

Authors

Philippe Garteiser¹, Laurent Castera^{1

2}, Muriel Coupaye^{1

3}, Sabrina Doblas¹, Daniela Calabrese^{1

4}, Marco Dioguardi Burgio^{1

5}, Séverine Ledoux^{1

3}, Pierre Bedossa^{1

6}, Marina Esposito-Farèse^{7

8}, Simon Msika^{1

4}, Bernard E Van Beers^{1

5}, Pauline Jouët⁹

Affiliations

¹ Centre de recherche sur l'Inflammation, Inserm U1149, Université de Paris, F-75018 Paris, France.
² Service d'Hépatologie, Hôpital Beaujon, Assistance Publique-Hôpitaux de Paris, F-92110 Clichy, France.
³ Service des Explorations Fonctionnelles, Centre Intégré Nord Francilien de l'Obésité (CINFO), Hôpital Louis Mourier, Assistance Publique-Hôpitaux de Paris, F-92700 Colombes, France.
⁴ Service de chirurgie digestive, Centre Intégré Nord Francilien de l'Obésité (CINFO), Hôpital Bichat-Claude Bernard, Assistance Publique-Hôpitaux de Paris, F-75018 Paris, France.
⁵ Service de Radiologie, Hôpital Beaujon, Assistance Publique-Hôpitaux de Paris, F-92110 Clichy, France.
⁶ Service de Pathologie, Hôpital Beaujon, Assistance Publique-Hôpitaux de Paris, F-92110 Clichy, France.
⁷ Unité de Recherche Clinique, Hôpital Bichat, AP-HP.Nord - Université de Paris, Assistance Publique-Hôpitaux de Paris, Paris, F-75018, France.
⁸ INSERM CIC-EC 1425, Centre d'Investigation Clinique, Hôpital Bichat, Assistance Publique-Hôpitaux de Paris, Paris, F-75018, France.
⁹ Service de Gastroentérologie, Hôpital Avicenne, Assistance Publique-Hôpitaux de Paris, F-93000 Bobigny, France.

Abstract

Background & aims: Tools for the non-invasive diagnosis of non-alcoholic steatohepatitis (NASH) in morbidly obese patients with suspected non-alcoholic fatty liver disease (NAFLD) are an unmet clinical need. We prospectively compared the performance of transient elastography, MRI, and 3 serum scores for the diagnosis of NAFLD, grading of steatosis and detection of NASH in bariatric surgery candidates.

Methods: Of 186 patients screened, 152 underwent liver biopsy, which was used as a reference for NAFLD (steatosis [S]>5%), steatosis grading and NASH diagnosis. Biopsies were read by a single expert pathologist. MRI-based proton density fat fraction (MRI-PDFF) was measured in an open-bore, vertical field 1.0T scanner and controlled attenuation parameter (CAP) was measured by transient elastography, using the XL probe. Serum scores (SteatoTest, hepatic steatosis index and fatty liver index) were also calculated.

Results: The applicability of MRI was better than that of FibroScan (98% vs. 79%; p <0.0001). CAP had AUROCs of 0.83, 0.79, 0.73 and 0.69 for S>5%, S>33%, S>66% and NASH, respectively. Transient elastography had an AUROC of 0.80 for significant fibrosis (F0-F1 vs. F2-F3). MRI-PDFF had AUROCs of 0.97, 0.95, 0.92 and 0.84 for S>5%, S>33%, S>66% and NASH, respectively. When compared head-to-head in the 97 patients with all valid tests available, MRI-PDFF outperformed CAP for grading steatosis (S>33%, AUROC 0.97 vs. 0.78; p <0.0003 and S>66%, AUROC 0.93 vs. 0.75; p = 0.0015) and diagnosing NASH (AUROC 0.82 vs. 0.68; p = 0.0056). When compared in "intention to diagnose" analysis, MRI-PDFF outperformed CAP, hepatic steatosis index and fatty liver index for grading steatosis (S>5%, S>33% and S>66%).

Conclusion: MRI-PDFF outperforms CAP for diagnosing NAFLD, grading steatosis and excluding NASH in morbidly obese patients undergoing bariatric surgery.

Lay summary: Non-invasive tests for detecting fatty liver and steatohepatitis, the active form of the disease, have not been well studied in obese patients who are candidates for bariatric surgery. The most popular tests for this purpose are Fibroscan, which can be used to measure the controlled attenuation parameter (CAP), and magnetic resonance imaging, which can be used to measure the proton density fat fraction (MRI-PDFF). We found that, when taking liver biopsy as a reference, MRI-PDFF performed better than CAP for detecting and grading fatty liver as well as excluding steatohepatitis in morbidly obese patients undergoing bariatric surgery.

Keywords: AUROC, area under the receiver operating characteristic curve; CAP; CAP, controlled attenuation parameter; FLI, fatty liver index; FLIP, fatty liver inhibition of progression; HSI, hepatic steatosis index; LSM, liver stiffness measurement; MRI-PDFF; MRI-PDFF, MRI-proton density fat fraction; NAFLD; NAFLD, non-alcoholic fatty liver disease; NAS, NAFLD activity score; NASH; NASH, non-alcoholic steatohepatitis; NPV, negative predictive value; Non-invasive diagnosis; PPV, positive predictive value; ST, SteatoTest; Se, sensitivity; Sp, specificity; TE, transient elastography; bariatric surgery; steatosis; transient elastography.