Impact of wet storage and other factors on biofilm formation and contamination of patient-ready endoscopes: a narrative review

Published:September 12, 2019DOI:
      The 2019 U.S. Food and Drug Administration report indicates that the clinical studies undertaken by the 3 main GI endoscope manufacturers demonstrate 5.4% of patient-ready duodenoscopes remain culture positive for high-concern organisms. The root causes of this persistent contamination are poorly understood. The objectives of this review include summarizing (1) the impact of inadequate manual cleaning and inadequate drying during storage on the formation of build-up biofilm in endoscope channels, (2) the impact of defoaming agents used during patient procedures on drying efficacy, (3) the data showing the importance of build-up biofilm on persistent microbial survival, and (4) the potential impact of implementation of a quality systems approach in GI endoscopy reprocessing.


      AER (automated endoscope reprocessor), BBF (build-up biofilm), CDC-HICPAC (Centers for Disease Control-Healthcare Infection Control Practices Advisory Committee), CFU (colony-forming unit), CRE (carbapenem-resistant Enterobacteriaceae), FDA (U.S. Food and Drug Administration), HEPA (high-efficiency particulate air), HLD (high-level disinfection), MDRO (multi-drug resistant organism), MIFU (manufacturer's instructions for use), PAA (peracetic acid), QS (quality system), SEM (scanning electron microscopy), TB (traditional biofilm), VBNC (viable but nonculturable)
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