Liver collagen in cirrhosis correlates with portal hypertension and liver dysfunction

Liver collagen proportionate area (CPA) assessed by computer-assisted digital image analysis has been proposed as an accurate and objective histological variable for subclassifying cirrhosis. The study aimed to examine the relationship between CPA and relevant clinical parameters in cirrhotic patients and to evaluate the sampling variability for CPA. The study included 48 consecutive liver transplantation patients with established cirrhosis. Hepatic venous pressure gradient (HVPG) and serum markers of liver failure were determined prior to transplantation. CPA was assessed in the explanted livers. In 20 of the livers, CPA was measured in more than one tissue sample. CPA showed significant correlations with HVPG and with various surrogate markers of hepatic dysfunction including albumin, bilirubin, INR, MELD score and Child-Pugh score. CPA reliably discriminated HVPG ≥10 mmHg, termed 'clinically significant portal hypertension' (area under receiver operator curve: 0.923, p < 0.001; odds ratio: 1.209, p = 0.003). CPA measured on tissue blocks showed no significant sampling variability (p > 0.5). In conclusion, the study correlated portal hypertension and hepatic dysfunction with the amount of collagen in cirrhotic livers. The findings support the presumption of CPA as a useful histological marker for subclassifying cirrhosis and as a helpful supplement to the qualitative description of hepatic architectural changes in routine pathology.