title: Detection and clinical relevance of human endotoxemia.
abstract: An optimized chromogenic assay for the detection of endotoxins in human blood is described. The assay comprises the removal of the inhibitory activity of plasma components by a dilution plus heating procedure, endotoxin-dependent activation of Limulus amebocyte lysate, and chromogenic measurement of the activated lysate. The assay has a detection limit of 3 ng endotoxin/L plasma. At the 10 ng/L level within-assay CV and between-assay CV of 14 and 21% were obtained respectively. In a prospective clinical trial including 473 consecutive febrile patients the assay has previously been demonstrated to have positive and negative predictive values of 48% and 99% for impending Gram-negative sepsis, respectively. In a similar study in 76 consecutive patients with Gram-negative infection of the urinary tract, these values were 73% and 95%, respectively. We conclude that this assay may provide the means to select those patients who are most likely to benefit from anti-endotoxin treatment. To facilitate endotoxin testing in other laboratories, a preliminary evaluation of a commercial endotoxin assay versus our own method was performed with 108 duplicate blood samples obtained from septic patients. With this assay detection limits of 2-3 ng endotoxin/L plasma could be obtained, as well as a good correlation (r = 0.94) and level of consensus to establish endotoxemia (93%) as compared to the house method. The commercial assay may therefore facilitate the introduction of endotoxin testing in other laboratories.
authors.affiliation: Department of Clinical Chemistry, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Sturk
authors.forename: S J
authors.initials: SJ
authors.lastname: van Deventer
authors.forename: C H
authors.initials: CH
authors.lastname: Wortel
authors.forename: J H
authors.initials: JH
authors.lastname: Levels
authors.forename: J W
authors.initials: JW
authors.lastname: ten Cate
authors.forename: H R
authors.initials: HR
authors.lastname: Büller
authors.forename: G T
authors.initials: GT
authors.lastname: Sanders
mesh_terms: D001424:Bacterial Infections / Q000175:diagnosis*; D002863:Chromogenic Compounds; D004731:Endotoxins / Q000097:blood*; D006090:Gram-Negative Bacteria; D006801:Humans; D008070:Lipopolysaccharides / Q000097:blood*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D014115:Toxemia / Q000175:diagnosis*; D014552:Urinary Tract Infections / Q000175:diagnosis*
chemical_list: D002863:Chromogenic Compounds; D004731:Endotoxins; D008070:Lipopolysaccharides