Microbiological surveillance of flexible bronchoscopes after a high-level disinfection with peracetic acid: preliminary results from an Italian teaching hospital

Background. Flexible bronchoscopes are heat labile, complex and difficult to clean, and some nosocomial outbreaks related to bronchoscopy have been reported in literature. The aim of our study was to determine, through a systematic monitoring, whether bronchoscopes' cleaning and disinfection procedures have been correctly adopted by health operators. Methods. We conducted a 19 months-long prospective study in the Unit of Pulmonology at Careggi Teaching Hospital (Florence, Italy), analyzing endoscopes that were reprocessed through a high-level disinfection procedure. Samples collection was performed weekly by two trained operators. Results were organized in a database and then exported for descriptive and inferential statistical analysis. Results. From February 2016 to September 2017 we collected 218 samples from bronchoscopes' valves (N=109) and from their inner channels (N=109). Staphylococci were found in 34 samples (15.69% of all samples). Pseudomonas was found in 11 samples (5.04% of all samples). Pseudomonas aeruginosa wasn't found in any sample. Conclusions. Our results came out to be better than similar studies in literature and demonstrated that a correct endoscopes' hygiene should be part of a more complex strategy of surveillance and control of healthcare-associated infections. However, a continuous monitoring of endoscopes could provide a wider view about this problem, and more reliable results.