Compare the Combined Diagnostic Accuracy of Transient Elastography and Visual Liver Score in Assessing Non-Alcoholic Fatty Liver Disease (NAFLD) and Compare it with Liver Biopsy in Morbidly Obese Patients Undergoing Bariatric Surgery: An Observational Study

Introduction

A liver biopsy is the gold standard for the diagnosis of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). Here, we combine preoperative transient elastography (TE) and intraoperative standardized visual liver score (VLS) which is compared with intraoperative liver biopsy for prediction of NAFLD and NASH in patients undergoing bariatric surgery.

Aim

Evaluate the combined diagnostic accuracy of TE and VLS in assessing NAFLD or NASH and compare it with liver biopsy in patients undergoing bariatric surgery.

Methods

In a prospective cohort of 70 morbidly obese undergoing bariatric surgery, preoperative TE and intraoperative VLS were calculated. Findings of TE and VLS were compared with histology from intraoperative liver biopsy.

Results

Histologically, 44 (62.85%) had NAFLD (≥ S1). Significant steatosis was seen in 20 (28.57%) while significant fibrosis was visible in 18 (25.71%). Area Under the Receiver Operating Characteristics (AUROC) TE for diagnosis of NAFLD was excellent (0.844, p = 0.001). At the optimal cutoff of 8.1, the positive predictive value (PPV) was 92.9%, and diagnostic accuracy was 90.6%. VLS had a sensitivity of 90.9% for NAFLD. The combined sensitivity of TE + VLS was 95.5% for ruling out NAFLD. Fourteen (20%) had NASH. VLS had a diagnostic accuracy of 97% in identifying NASH in comparison to TE. AUROC-VLS was 0.987, p ≤ 0.001, and a sensitivity of 100%. The overall sensitivity of combined TE and VLS was 100% with a negative predictive value (NPV) of 100%.

Conclusion

TE when combined with intraoperative VLS is comparable to liver biopsy and can be used for the diagnosis of NAFLD and NASH in patients undergoing bariatric surgery.

Graphical Abstract