Comparative assessment of liver fibrosis by computerized morphometry in naïve patients with chronic hepatitis B and C.

Background: Liver fibrosis, now assessed by liver biopsy or using non-invasive methods, might be different in chronic hepatitis B (CHB) and chronic hepatitis C (CHC).
Aim: To compare histological amount and pattern of fibrosis in CHB and CHC.
Methods: Sixty CHB and sixty CHC biopsies from naïve patients, standardized for the spectrum of Metavir fibrosis stages, were analysed for (1) semi-quantitative Metavir activity, steatosis, perisinusoidal fibrosis, alpha-smooth muscle actin immunoreactivity, (2) quantitative morphometry of total and perisinusoidal fibrosis ratio (FR and PFR).
Results: Biopsy quality, activity, steatosis, Fibrotest(®) values were not different between the two groups. Correlation between FR and fibrosis stage was stronger in CHB (r = 0.90) than CHC (r = 0.81). Mean FR was 1.5-fold higher in CHC than CHB for early fibrosis stages (F ≤ 2, P = 0.001), with higher PFR in CHC for F0 (P = 0.001), F1 (P = 0.08) and F2 (P = 0.004). Hepatic stellate cell activation index was also higher in CHC than in CHB (P = 0.007). Diagnosis performance of FR for significant fibrosis was not statistically different in CHB than CHC (AUROC 0.92 and 0.87 respectively), but cut-offs optimizing sensitivity and specificity were higher in CHC and their extrapolation to CHB led to 10% decrease in sensitivity. In F ≤ 2 patients, correlation between FR and Fibrotest(®) was only significant in CHC.
Conclusions: As compared to CHB, amount of fibrosis is greater in CHC for F ≤ 2 patients, mainly because of higher perisinusoidal fibrosis. These data illustrate difficulty to assess early fibrosis stages by non-invasive methods, and support the need for specific cut-offs in CHB.
(© 2012 John Wiley & Sons A/S.)