Measurement of endotoxin activity in critically ill patients using whole blood neutrophil dependent chemiluminescence.

Abstract

BACKGROUND:

Lipopolysaccharide (endotoxin) from the cell wall of Gram-negative bacteria is a potent trigger for the release of host-derived inflammatory mediators. The relationship between endotoxaemia, Gram-negative infection and the clinical syndrome of sepsis has been difficult to establish, in part because of the limitations of available endotoxin assays.

METHODS:

We performed an observational cohort study in critically ill patients in the medical/surgical intensive care unit (ICU) of a tertiary care hospital. Whole blood endotoxin levels on the day of ICU admission were measured using a novel chemiluminescent assay--the endotoxin activity assay (EAA)--and the chromogenic modification of the limulus amoebocyte lysate (LAL) assay.

RESULTS:

We studied 74 consecutive admissions. Endotoxin levels were higher in patients with a diagnosis of sepsis (470 +/- 57 pg/ml) than in patients admitted with a diagnosis other than sepsis (157 +/- 140 pg/ml; P < 0.001). Endotoxaemia was significantly associated with Gram-negative infection (P < 0.05); no patient with a Gram-negative infection had an endotoxin level below 50 pg/ml. White blood cell counts of patients with EAA-detected endotoxaemia were significantly higher (15.7 +/- 9.1 x 10(9) cells/l for endotoxaemic patients versus 10.8 +/- 6.2 x 10(9) cells/l for patients without endotoxaemia; P < 0.05).

CONCLUSION:

Endotoxaemia is associated with Gram-negative infection from any source, and with a diagnosis of sepsis and leukocytosis. These correlations were not apparent using the LAL method. The EAA may be a useful diagnostic tool for the investigation of invasive Gram-negative infection and incipient sepsis.

• Authors: John C Marshall, Paul M Walker, Debra M Foster, David Harris, Melanie Ribeiro, Jeff Paice, Alexander D Romaschin, Anastasia N Derzko
• Journal: Critical care (London, England) (Crit Care) Vol. 6 Issue 4 Pg. 342-8 (Aug 2002) ISSN: 1364-8535 [Print] England
• PMID: 12225611 (Publication Type: Journal Article)

Chemical References

• Endotoxins

Topics

• APACHE
• Adult
• Aged
• Aged, 80 and over
• Cohort Studies
• Endotoxemia (classification, metabolism, mortality)
• Endotoxins (blood)
• Female
• Humans
• Intensive Care Units
• Length of Stay
• Luminescent Measurements
• Male
• Middle Aged
• Pneumonia (microbiology)