Table 2.
Outbreaks and pseudo-outbreaks reported in connection with biofilm or peracetic acid-based processing of flexible endoscopes
| Number/type of infection(s) | Pathogen(s) | Type of endoscopic procedure | Reason for outbreak / pseudo-outbreak | Peracetic acid-based formulations were used for | Ref. |
| None (pseudo-outbreak) | Pseudomonas aeruginosa | Gastroscopy, bronchoscopy | Suboptimal duration of glutaraldehyde application during disinfection; “resistance” to glutaraldehyde may have been enhanced by manual cleaning with peracetic acid-based disinfectant[214] | Cleaning step | [202] |
| 2: infection (not further specified)3: colonization | OXA-48 Klebsiella pneumoniae | Bronchoscopy | A problem with the washer disinfector or the cleaning procedure was assumed as the reason | Cleaning step and disinfection step (Gastmeier P, personal communication) | [203] |
| 4: pneumonia (3 cases); colonization (1 case) | MDR Pseudomonas aeruginosa | Gastroscopy | Insufficient initial cleaning, shortening of the immersion time and brushing time, insufficient channel flushing, and inadequate drying prior to storage | Disinfection step | [124] |
| 4: bacteraemia, biliary tract infection, respiratory tract infection9: colonisation | KPC-2 Klebsiella pneumoniae | Duodenoscopy | Contaminated duodenoscope; reason for outbreak: inadequate cleaning | Disinfection step | [204] |
| 8: bloodstream infection4: biliary tract infection4: colonization | ESBL Klebsiella pneumoniae (CTX-M-15) | ERCP | Insufficient manual cleaning, insufficient drying after processing | Disinfection step | [125] |
| 3: sepsis | Pseudomonas aeruginosa | ERCP | Presence of biofilm on undamaged channels | Disinfection step (Kovaleva J; personal communication) | [205] |
| 5: infection (not further specified) 9: colonization | OXA-48 Klebsiella pneumoniae | Duodenoscopy | One endoscope had probably a defect resulting in insufficient disinfection | Disinfection step (Gastmeier P, personal communication) | [203] |
| 18: pulmonary infection (4 cases, one of them died); colonization (14 cases) | Imipenem-resistant Pseudomonas aeruginosa | Bronchoscopy | Incorrect connectors joining the bronchoscope suction channel to the STERIS SYSTEM 1 processor | “Automatic processing” | [206] |
| 2: bacteremia and biliary tract infection 4: colonization | KPC-2 Klebsiella pneumoniae | Gastroscopy | Delayed pre-wash resulting in drying of the gastroscope; short drying period after the peracetic acid treatment resulting in incomplete drying | “Wash” | [207] |
ERCP: Endoscopic retrograde cholangiopancreatography.