Comparison of diagnostic ability of new blood endotoxin measurement method using leukocyte-rich plasma sample and existing sepsis markers

Abstract

The plasma sample, which contains almost no leukocytes, is generally used to measure endotoxin levels in blood. However, it is known that the diagnostic ability is not high. We assumed that most endotoxins exist in a state trapped by leukocytes, and then we have devised a method (LRP37 method) to obtain leukocyte-rich plasma (LRP) for measuring blood endotoxins. In this study, we selected the following two methods for measuring endotoxins in the LRP; the conventional turbidimetric kinetic assay (TKA) and the semi-automated luminescent substrate method (SALS) using the leukocyte fraction obtained the LRP. The endotoxin levels obtained from these methods were compared with the diagnostic ability of existing sepsis markers. The target cases were 40 who were admitted to our institution. Comparing the non-infected group with the Gram-negative infected group, the area under the curve of TKA and SALS were 0.94 and 0.86, respectively, and these diagnostic capabilities were the best among all the markers tested.