Borescope examination and microbial culture results of endoscopes in a tertiary care hospital led to changes in storage protocols to improve patient safety

Published:September 16, 2022DOI:


      • Routine borescope examination is capable of identifying and internal damage.
      • Routine microbial cultures should be coupled with borescope examination to assure endoscopic safety.
      • Endoscopic dryness is rarely achieved after high level disinfection.


      Flexible endoscopes are highly versatile and useful medical instruments, and their proper reprocessing is critical to patient health and safety. The value of routine visual inspections and surveillance of endoscopes in a tertiary care hospital was assessed by performing borescope examinations and microbial sampling on respiratory, gastro-intestinal (GI), and urological endoscopes.


      A total of 42 endoscopes were cultured, and 36 endoscopes were examined with a borescope. The flush-brush-flush method was used to culture the endoscopes. Collected water was suctioned through a membrane filter device which was plated on a blood agar plate and incubated. A borescope was used to perform endoscope inspection in an antegrade and retrograde approach.


      Positive microbial cultures were seen in 28% of respiratory, 22% of GI, and 30% of urological endoscopes. Borescope examinations revealed multiple abnormalities and damage including channel shredding, filamentous debris, water retention, discoloration, dents, and red particles.


      Borescope examination and microbial culturing should be used routinely to assure endoscopic safety. Borescope examination enabled us to visualize structural damage, foreign material and moisture within endoscopes. The structural damages and the particles found in endoscopes resulted in timely repair and discontinuation of this type of distal end protectors in our facility.

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