Bi-lobar liver biopsy via EUS enhances the assessment of disease severity in patients with non-alcoholic steatohepatitis

Background: In patients with non-alcoholic fatty liver disease (NAFLD), all-cause mortality increases with fibrosis stage. Liver biopsy (LB), performed predominantly in the right lobe, assesses fibrosis, however, right lobe LB may not be sufficient due to histological variation in different lobes. Endoscopic ultrasound (EUS) allows for biopsy of right and left liver lobes in the same setting.

Methods: This retrospective study assessed for histologic variability amongst left and right liver lobe (L:R) specimens obtained via EUS at a tertiary care center. Between January 2012 and December 2015, 38 NAFLD patients underwent LB, in whom both lobes were sampled.

Results: L:R agreement was near-perfect for steatosis (κ = 0.816, 95% CI 0.674, 0.958), good for ballooning (κ = 0.740, 95% CI 0.565, 0.916) and moderate for lobular inflammation (κ = 0.401 95% CI 0.110, 0.692) and fibrosis (κ = 0.473, 95% CI 0.275, 0.672). Intra-observer variability assessed by blinded repeat slide readings was almost perfect for fibrosis and steatosis (κ = 1, 95% CI 1, 1 and κ = 0.939, 95% CI 0.881, 0.997 respectively) and substantial for lobular inflammation (κ = 0.725, 95% CI 0.584, 0.866). Only right lobe assessment underestimated fibrosis in 21%, inflammation in 13%, and steatosis and ballooning in 8% cases.

Conclusions: These data indicate that in NAFLD, due to regional variation, EUS-guided bi-lobar LB improves assessment of disease activity and fibrosis.