Pre- and Post-Processing Evaluations of Manual and Automated Endoscopes: A Microbiological Isolation

Abstract

Introduction. An endoscope is a flexible tube equipped with a camera and a light used for the diagnosis and treatment of digestive pathologies. Although healthcare-associated infections are uncommon, they represent a significant concern. Proper endoscope reprocessing is essential to prevent infections, requiring adherence to established guidelines for cleaning, disinfection, and storage. 

Objetive. To compare the effectiveness of manual and automated reprocessing of video gastroscopes and colonoscopes through microbiological monitoring of the following microorganisms: ESBL Escherichia coli, Shigella spp., Salmonella spp., Pseudomonas aeruginosa, Klebsiella pneumoniae carbapenemase (KPC)-producing, and vancomycin-resistant Enterococcus spp. 

Materials and Methods. A prospective, observational, descriptive study was conducted, in which 207 reprocessing procedures of video gastroscopes and colonoscopes were selected for evaluation. Of these, 103 were manual and 104 were automated. The procedures were evaluated in both the pre- and post-processing stages. Cultures were performed to isolate ESBL Escherichia coli, Shigella spp., Salmonella spp., Pseudomonas aeruginosa, Klebsiella pneumoniae carbapenemase (KPC)-producing, and vancomycin-resistant Enterococcus spp. 

Results. In the pre-reprocessing samples, ESBL Escherichia coli was isolated in 45% of cases, compared to 55% for manual and automated reprocessing, respectively. Similarly, Pseudomonas aeruginosa was isolated in 36% of cases for manual reprocessing and 18% for automated reprocessing. Salmonella spp. was isolated in 18% of cases for both manual and automated reprocessing. Finally, vancomycin-resistant Enterococcus spp. was isolated in 9% of automated reprocessing samples. The results of the manual post-processing demonstrated that 1% of the samples exhibited counts of 1,000–99,999 colony-forming units (CFU)/ml, while 6% exhibited counts exceeding 100,000 CFU/ml. The automated method demonstrated a 7% prevalence of samples with over 100,000 colony-forming units (CFU) per milliliter. A comparison of the two modalities revealed that pathogens were not identified in seven of the 103 manual samples and six of the 104 automated samples. The only growth observed in the automated samples was that of coagulase-negative Staphylococcus, which is a potential contaminant. However, one automated sample did yield Salmonella spp. 

Conclusion. The results obtained were comparable between the two methodologies. The automated reprocessing revealed the presence of an enteropathogen, which will allow for a reassessment of the reprocessing steps in order to enhance the efficacy of the procedures.