Impact of hepatic clearance of endotoxin using endotoxin activity assay

Background Endotoxin (Et) in the portal vein blood is processed by the hepatic reticuloendothelial system, and therefore, it is possible that the hepatic clearance of Et may become a biological index for liver function. In this study, Et levels of preoperative peripheral and portal vein blood at the time of liver transplantation (LT) were measured in order to study the meaning. Methods The study population comprised 19 patients in whom pediatric living donor LT was performed. In the preoperative peripheral and the portal vein blood at the time of LT, we measured Et activity (EA) by the Et activity assay (EAA) and the Limulus amebocyte lysate (LAL) method. Results The preoperative peripheral vein blood showed a low EA in all cases. In the EA of the peripheral and the portal vein blood, the latter showed a significantly high level ( p = 0.049). With the LAL method, 5.3% (2/38) of patients were positive for Et. Conclusions The EAA is considered to be superior to the LAL method for the detection of Et, even in low endotoxinemia, and is also capable of elucidating the Et kinetics by accurately reflecting hepatic clearance.