Organ dysfunction in cirrhosis: a mechanism involving the microcirculation.

Abstract

Microcirculation is essential for adequate tissue perfusion and organ function. Microcirculatory changes may occur in cirrhosis, inducing loss of multiorgan function. The aim was to evaluate preliver transplantation and postliver transplantation aspects of multiorgan function, microcirculation, inflammatory, and endothelial biomarkers and survival in a controlled study including cirrhotic outpatients. We accessed functional capillary density (FCD) and red blood cell acceleration (RBCA) by nailfold videocapillaroscopy. Inflammatory and endothelial biomarkers [interleukin-6 (IL-6), soluble intercellular adhesion molecule-1, endothelin-1, and tumor necrosis factor-α] were analyzed. Cerebral and renal functions were assessed to represent organ dysfunction and regression analyses were carried out. Receiver operating characteristic curves were constructed and survival Kaplan-Meier analysis was carried out. Fifty-four patients and 18 controls were included. Inflammatory and endothelial markers increased in advanced disease. FCD was reduced and RBCA was progressively lower according to disease severity. RBCA correlated inversely with inflammatory and endothelial biomarkers, and directly with renal function. The presence of hepatic encephalopathy correlated inversely with RBCA and directly with IL-6 and endothelin-1. In multivariate analysis, RBCA was an independent factor for organ dysfunction. The area under the receiver operating chartacteristic curve for IL-6 for survival was 0.74 (0.59-0.89), P=0.05. Transplant-free survival was 97.5% for values under 5.78 ng/ml (IL-6 best cutoff) and 83.9% above 5.78 ng/ml, log-rank=0.018. Eleven patients underwent transplantation, with an overall improvement in microcirculatory function. Our results suggest a mechanism of organ damage in cirrhosis, where microcirculatory dysfunction could be correlated to inflammatory and endothelial biomarkers, and loss of multiorgan function. IL-6 seems to be an important survival marker of inflammation. Liver transplantation improved microcirculatory dysfunction, corroborating this hypothesis.