Endotoxin release and endotoxin neutralizing capacity during colonoscopy.

Area of Science:

• Gastroenterology
• Immunology
• Clinical Microbiology

Background:

• Endotoxins are potent inflammatory molecules originating from bacterial cell walls.
• Minimal invasive procedures like colonoscopy may pose a risk of endotoxin exposure.
• Assessing endotoxin levels and the body's response is crucial for understanding procedural risks.

Purpose of the Study:

• To investigate the occurrence of endotoxemia during elective colonoscopy.
• To evaluate changes in endotoxin levels and endotoxin neutralizing capacity (ENC) during the procedure.
• To determine the clinical significance of endotoxin detection during colonoscopy.

Main Methods:

• Plasma endotoxin levels and ENC were measured in 38 patients undergoing colonoscopy using the limulus amebocyte lysate test.
• A control group of 10 patients was also sampled.
• Measurements were taken before, during, and after the colonoscopy procedure.

Main Results:

• Elevated plasma endotoxin levels were observed during colonoscopy compared to pre-procedure levels.
• Timed endotoxin plasma levels did not significantly change with the conventional test.
• Endotoxin neutralizing capacity (ENC) significantly decreased during endoscopy, with maximal reduction at the end of the procedure.
• ENC levels returned to baseline 24 hours post-colonoscopy.
• These findings suggest a short endotoxin half-life in circulation, making direct detection challenging but revealing a reduction in ENC.

Conclusions:

• Colonoscopy can lead to significant endotoxemia, evidenced by decreased ENC.
• The body's capacity to neutralize endotoxins is impaired during this minimal invasive procedure.
• Modified limulus amebocyte lysate testing for ENC provides a sensitive method to detect endotoxemia during colonoscopy.