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Volume 18 Supplement 2

Sepsis 2014

  • Poster presentation
  • Open Access

Endotoxin Activity Assay levels correlate with the microbiological results of Gram-negative organisms in septic patients

  • M Tsunoda1,
  • M Kang1,
  • M Saito1,
  • N Saito1,
  • M Namiki1,
  • T Harada1,
  • M Takeda1 and
  • A Yaguchi1
Critical Care201418(Suppl 2):P73

Published: 3 December 2014


White Blood CellSeptic PatientProcalcitoninMicrobiological CultureSofa Score


The Endotoxin Activity Assay (EAA™; Spectral Diagnostics Inc., Toronto, Canada) is a useful diagnostic test for sepsis due to Gram-negative infection and is based on the reaction of neutrophils to endotoxin complexed with an anti-endotoxin antibody. However, the relations between values of EAA and microbiological data have not been elucidated. Our hypothesis is that EAA values correlate to the results of microbiological cultures and also severity.


From July 2008 to July 2013, all adult patients with suspected sepsis admitted to our medico-surgical ICU in whom EAA was measured were included in this study. Data collected included age, gender, ICU mortality, white blood cell (WBC) count, C-reactive protein (CRP), procalcitonin (PCT), EAA levels, SOFA score and results of microbiological culture. Patients with no microbiological data were excluded. Data were analyzed by Kruskal-Wallis test, Mann-Whitney U test and multivariate logistic regression. P < 0.05 was considered significant.


Of 569 patients (353 men and 216 women; mean age 66.0 ± 17.4 years), 283 patients had Gram-negative infection and 286 patients had no Gram-negative infection. Of 283 patients with Gram-negative infection, 65 patients had Gram-negative organisms in blood. EAA levels were significantly different between patients with Gram-negative blood, in other infectious sites and no Gram-negative infection (0.45 ± 0.21 vs. 0.39 ± 0.17 vs. 0.36 ± 0.15, P = 0.03). The odds ratio (95% confidence interval (CI)) of EAA levels for Gram-negative infection and Gram-negative bacteremia were 3.89 (1.44 to 10.4) (P = 0.007) and 3.36 (2.16 to 40.6) (P = 0.003), respectively. The odds ratio and CI of age and SOFA score for ICU mortality were 1.03 (1.01 to 1.04) (P = 0.0003) and 1.33 (1.26 to 1.41) (P < 0.0001), respectively, while gender, WBC, CRP, PCT and EAA levels had no relations with ICU mortality. SOFA score was significantly higher in patients with Gram-negative infection than in patients with no Gram-negative infection (8.0 ± 4.6 vs. 6.7 ± 4.2, P = 0.0003).


EAA levels related to the detections of Gram-negative organisms in cultures. Thus, a high EAA level may show the existence of Gram-negative organisms in patients' sites. EAA levels had relations with SOFA score but no relations with ICU mortality.

Authors’ Affiliations

Department of Critical Care and Emergency Medicine, Tokyo Women's Medical University, Tokyo, Japan


© Tsunoda et al.; licensee BioMed Central Ltd. 2014

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated.