Are Noninvasive Methods Comparable to Liver Biopsy in Postoperative Patients After Roux-en-Y Gastric Bypass?

Abstract

Introduction: Transient tissue elastography (TTE) may estimate the degree of hepatic fibrosis in patients with obesity, but the method has restrictions that are mainly related to patients' BMI.

Purpose: To compare the results of the evaluation of hepatic fibrosis by biochemical methods and TTE with those determined by liver biopsy in patients after RYGB.

Methods: This was a cross-sectional study involving patient data, TTE, and liver biopsy 1 year after RYGB.

Results: Of the 94 selected patients, 33 underwent TTE and liver biopsy. The average weight of patients was 84.4 ± 15.4 kg. The mean APRI was 0.2 ± 0.1, and 36 patients (97.3%) were classified as F0-F1. The average NFS was - 2.0 ± 1.0, with 25 patients (67%) classified as F0-F1 and 12 patients (32.4%) classified as F2. The agreement rate between Fibroscan and liver biopsy was 80.0%. Histological analysis revealed regression of inflammatory changes in all patients: 26 patients (72.2%) had some degree of non-alcoholic steatohepatitis (NAS ≥ 5), and after surgery, no patient presented inflammation upon biopsy. Nine patients (24.3%) had fibrosis at surgery, and only two (5.4%) still had fibrosis 1 year later (p < 0.008).

Conclusions: The use of APRI and Fibroscan is promising, but more studies are needed to evaluate patients with an advanced degree of NAFLD and confirm the entire spectrum of the disease.

Keywords: APRI; Fibroscan; Gastric bypass; Liver biopsy; NAFLD.