Background: Activation of Kupffer cells may be involved in the pathogenesis of portal hypertension by release of vasoconstrictive substances and fibrosis due to co-activation of hepatic stellate cells.
Aim: To study soluble plasma (s) CD163, a specific marker of activated macrophages, as a biomarker for portal hypertension in patients with liver cirrhosis.
Methods: We measured sCD163 concentration and the hepatic venous pressure gradient (HVPG) by liver vein catheterisation in 81 cirrhosis patients (Child-Pugh CP-A: n = 26, CP-B: n = 29, CP-C: n = 26) and 22 healthy subjects. We also measured their cardiac output (CO), cardiac index and systemic vascular resistance (SVR). Liver status was examined by Child-Pugh and MELD-score.
Results: In cirrhosis, sCD163 concentration was nearly three times higher than in controls (4.7 ± 2.5 vs. 1.6 ± 0.5 mg/L, P < 0.001). sCD163 was also higher, as measured in steps by CP-score (P < 0.001). The HVPG rose steeply to an asymptote of 22 mmHg with sCD163 up to about 5 mg/L and not to higher values with higher sCD163. In a multivariate analysis, sCD163 was the only independent predictor of the HVPG but did not predict any of the systemic circulatory findings. sCD163 > 3.95 mg/L (upper normal limit) predicted HVPG ≥ 10 mmHg with a positive predictive value of 0.99.
Conclusions: Circulating sCD163 originating from activated Kupffer cells is increased in cirrhosis with increasing Child-Pugh score and with increasing HVPG, and it is an independent predictor for HVPG. These findings support a primary role of macrophage activation in portal hypertension, and may indicate a target for biological intervention.
© 2012 Blackwell Publishing Ltd.