Comparing hepatic steatosis distribution patterns between non-alcoholic fatty liver disease and fatty liver disease with chronic hepatitis B by second-harmonic generation/two-photon excited fluorescence method.

Introduction And Objectives: Hepatitis B virus (HBV) might be an etiological factor modulating fat distribution in steatotic livers. We aim to compare hepatic steatosis distribution patterns between NAFLD and FL&CHB patients with second-harmonic generation (SHG)/two-photon excited fluorescence (TPEF) method.

Patients And Methods: 42 patients with NAFLD, 46 with FL&CHB and 55 without steatosis were enrolled in the study. Overall and regional steatosis in liver sections were quantified by SHG/TPEF method. The accuracy of which was validated by pathologist evaluation and magnetic resonance spectroscopy (MRS). Difference in degree of overall and regional steatosis between NAFLD and FL&CHB groups was analyzed by Mann-Whitney U test. Multivariable linear regression analysis was used to model factors contributing to steatosis distribution.

Results: The hepatic steatosis measured by SHG/TPEF method was highly correlated with pathologist grading (r=0.83, p<0.001) and MRS measurement (r=0.82, p<0.001). The level of overall steatosis in FL&CHB group is significantly lower than that in NAFLD group (p<0.001). In NAFLD group, periportal region has significantly lower steatosis percentage than lobule region and overall region (p<0.001); while in FL&CHB group there is no difference among regions. The ratio of steatosis at periportal region to lobule region is significantly higher in FL&CHB group than that in NAFLD group (p<0.05). Multivariable linear regression analysis shows that HBV infection is the major contributing factor (β=0.322, p<0.01).

Conclusions: SHG/TPEF method is an accurate and objective method in hepatic steatosis quantification. By quantifying steatosis in different histological regions, we found steatosis distribution patterns are different between FL&CHB and NAFLD patients.