ATP bioluminescence to validate the decontamination process of gastrointestinal endoscopes

Introduction Gastrointestinal endoscopes play an effective diagnostic role in modern medicine. The endoscopes become heavily contaminated with microorganisms during procedures and need careful reprocessing. Methods A prospective study was carried out at a gastroenterology hepatology unit to evaluate ATP bioluminescence, measured as relative light units (RLUs), to validate the decontamination processing of endoscopes. Flushes from endoscopes involved in 120 endoscopic procedures at four different stages: pre-patient (before the procedure), post-patient (after the procedure), post-cleaning (after manual cleaning) and post-disinfection were examined by ATP testing and microbiological culture. The hypothetical pass or fail limit of 100 RLUs was set according to previous studies in the literature. When the disinfection process failed, the above process was repeated. Results Average RLU readings were: pre-patient: 48; post-patient: 124052; post-cleaning: 1423; and post-disinfection: 144. The corresponding culture results were: pre-patient: all negative; post-patient: all positive except for four; post-cleaning: positive except for 26; and post-disinfection: all negative. Although 21 (17%) of post-disinfection specimens showed failed ATP levels of more than 100 RLUs, when the cleaning and disinfection process was repeated before they were used, all scopes then showed a pass level of less than 100 RLUs. Conclusions ATP bioluminescence has the potential to play an important role in the validation process. This process would allow a quick turnaround time following a simple check procedure to be classified as safe in a busy endoscopic unit.