Su1325 COMPARISON OF ENDOSCOPIC ULTRASOUND IMAGING WITH LIVER BIOPSY FOR DIAGNOSIS AND STAGING OF FATTY LIVER

Abstract

The accuracy of endoscopic ultrasound (EUS) imaging for the diagnosis of fatty liver disease is not known. By imaging the liver directly though the stomach wall, EUS may provide better assessment of the liver parenchyma than transabdominal ultrasound, especially in obese patients. Our goal was to compare the diagnostic accuracy of EUS with liver biopsy for diagnosis and staging of fatty liver. We identified all patients who underwent EUS guided liver biopsy at our institution from 2014-19. Patients with liver cancer were excluded. Liver images obtained during EUS were reviewed by an expert abdominal radiologist who graded the liver images using standard radiology criteria for fatty liver as the following: i) absent, ii) mild, ii) moderate, iii) severe. The radiologist was blinded to clinical information and final histology. The radiologist’s confidence level for grading was recorded as low or high certainty. Histology for each liver biopsy served as criteria standard. Information on patient demographics and comorbid conditions were also collected. A total of 76 patients underwent EUS guided liver biopsy and met study criteria. The mean age was 56.5 years and 50% were males. The average body mass index (BMI) was 30.1 kg/m2. Histological evidence of fatty liver was present in 47 (61%) patients, while moderate to severe fatty liver was present in 22 (28.9%) patients. Using histology as criteria standard, the overall accuracy for EUS for diagnosis of fatty liver was 68%, sensitivity was 92% and specificity was 31%. The agreement between radiologist determination and histologic determination of mild, moderate and severe steatosis was poor (kappa = 0.1). When only moderate to severe fatty liver was considered, the accuracy was 75%, sensitivity was 63% and specificity was 93%. Accuracy of EUS diagnosis in predicting fatty liver histology did not decrease with increasing BMI [OR 1.07, (95% CI: 0.98-1.17), p-value: 0.12). No difference between accuracy and radiologist’s level of diagnostic confidence was noted. Coarse liver texture noted on EUS had accuracy of 78%, sensitivity of 71%, and specificity of 78% for diagnosis of histologic stage 4 fibrosis or cirrhosis. EUS imaging is overall only modestly accurate for diagnosis and staging of fatty liver disease, but may serve as a useful screening tool as high sensitivity was achieved. These results are superior to those reported in the literature for transabdominal ultrasound, and are not affected by obesity.