1333. Prospective Comparative Effectiveness of Noninvasive Tests for Staging Hepatic Steatosis
Authors * Denotes Presenting Author
  1. Elliot Varney *; University of Mississippi Medical Center
  2. Elizabeth Kerby; University of Mississippi Medical Center
  3. Quinn Cottone; University of Mississippi Medical Center
  4. Merlin Manogaram; University of Mississippi Medical Center
  5. Seth Lirette; University of Mississippi Medical Center
  6. Candace Howard; University of Mississippi Medical Center
To prospectively compare the diagnostic performance of multiple noninvasive tests for staging hepatic steatosis in all patients with chronic liver disease using histology from biopsy as the reference standard.

Materials and Methods:
This is an IRB-approved, HIPAA-compliant, prospective, single-center pilot study including adults with various degrees of chronic liver disease and hepatic steatosis referred for liver biopsy. All patients underwent the reference standard random liver biopsy and noncontrast CT imaging of the upper abdomen was performed. Liver attenuation measurements of the liver parenchyma were obtained using a circular Region-of-Interest (ROI). Serum labs within 30 days of liver biopsy were obtained and used to calculate the nonalcoholic fatty liver disease (NAFLD), fibrosis score (NFS), and hepatic steatosis index (HSI). Magnetic Resonance Imaging (MRI) of the abdomen was performed using a 1.5T Siemens scanner using standard acquisition parameters with calculation of focal hepatic and full-liver percent density fat fraction (PDFF). The concordance of focal MR-PDFF (MR-PDFF ROI), full-liver MR-PDFF (MR-PDFF Segmentation), CT Liver attenuation, NFS, and HSI with histologic nonalcoholic steatohepatitis (NASH) Clinical Research Network (CRN) staging of hepatic steatosis were assessed using Harrell's C statistics.

All 29 patients (22 women; age range 21 - 72, mean 54 years) were included. Mean interval between liver biopsy, serum labs and MRI was 0 days. The histologic range of hepatic steatosis includes stages 0 (<5% of steatosis) to 3 (>67% steatosis). Mean (range) of MR-PDFF ROI was 16.0 (1.3 - 100.0). Mean (range) of MR-PDFF segmentation was 17.5 (2.1 - 99.9). Mean (range) of NFS and HSI score were -0.75 (-4.6 - 1.3) and 82.9 (5.5 - 224.3), respectively. The C-stat concordance for MR-PDFF ROI, MR-PDFF segmentation, CT liver attenuation, NFS, and HIS was 0.92, 0.98, 0.86, 0.47, and 0.61, respectively. Odds of moving up one steatosis stage per one-unit increase were 1.18 (p = 0.008), 1.8 (p = 0.001), 0.86 (p < 0.001), 1.22 (p = 0.398), and 1.0 (p = 0.492), respectively.

In this pilot study, MR-PDFF segmentation and MR-PDFF ROI were the superior methods for assessing the degree of hepatic steatosis in all comers with chronic liver disease, not limited by a previous NAFLD diagnosis. Additionally, liver attenuation measures proved concordant with biopsy, whereas previously validated serum markers for NAFLD showed overall poor performance in staging hepatic steatosis.