The comparison of scoring scales for liver biopsy assessment in morbidly obese patients undergoing bariatric surgery

Background: Many scoring systems have been applied for the grading and staging of non-alcoholic fatty liver disease (NAFLD). There is no consensus according to semiquantitative scales for the assessment of steatosis, inflammatory grading, and fibrosis staging in NAFLD. Methods: We analysed 24 consecutive patients who underwent bariatric surgery. The grading for steatosis was estimated according to the systems proposed by Brunt and by Dixon. Brunt's scale and Scheuer's scale modified by Gabriel were used for inflammatory activity and fibrosis staging. Additionally, types of NAFLD disease were diagnosed according to Matteoni's classification. Results: Steatosis was observed in 88% and steatohepatitis in 54% of patients. We observed portal, periportal and pericellular fibrosis. Neither bridging fibrosis nor cirrhosis were found. Extent of steatosis estimated according to Dixon and Brunt's scales was positively associated with appearance of steatohepatitis. The comparison of Dixon's and Brunt's scales according to grade of steatosis demonstrated a statistically significant difference. Inflammatory activity grades and fibrosis stages assessed according to Scheuer and Brunt scales differ significantly. Inflammatory activity evaluated with the Brunt scale was associated with the extent of steatosis and occurrence of steatohepatitis. Conclusions: Non-advanced forms of liver fibrosis do not appear to be dependent on steatosis and inflammatory grade in NAFLD. It is necessary to find the precise estimation of extent of steatosis especially occupying less than 1/3 or 1/4 of the lobule area. Brunt's scale seems to be more useful for the estimation of liver biopsy in NAFLD. It is essential to create a consensus for evaluation of steatosis and necroinflammatory grading and fibrosis staging in NAFLD.