Testing duodenoscope after 60 ERCP procedures or once a month. This algorithm describes the process for testing a duodenoscope after 60 ERCP procedures or once a month. First, test the duodenoscope and consider holding the instrument until culture results available. Culture method options are: (A) Presence/ Absence by Enrichment or (B) Quantitative. If negative, reprocess again to remove PBST and return to circulation. If positive, with any high-concern organisms, examples include Staphylococcus aureus, Enterococcus spp., Streptococcus sp. viridians group, Pseudomonas aeruginosa, Klebsiella spp., Salmonella spp., Shigella spp. and other enteric gram-negative bacilli, then 1. reprocess and culture again, 2. do not return to circulation until cultures are negative or are below acceptable levels of low concern organisms†, and 3. consider notification of patients exposed to duodenoscope since last negative cultures. If positive, with any low-concern organisms, examples include coagulase-negative staphylococci, micrococci, diptheroids, Bacillus spp. and other gram-positive rods , then for culture method enrichment, 1. Reprocess and culture again, and 2. Do not return to circulation until cultures are negative or are below acceptable levels of low-concern organisms† OR for culture method quantitative, 1. Quantify colonies, if ˂10 CFU/duodenoscope†, reprocess to remove PBST and return to circulation, 2. If not <10CFU/duodenoscope, review facility-specific acceptable levels†, reprocess and culture again if not below acceptable levels, and 3. Do not return to circulation until cultures are negative or are below acceptable levels of low-concern organisms†. If cultures are repeatedly positive (3 times or more) for either any high- concern organism or >10 CFU/duodenoscope of low-concern organisms, facilities should consider re-evaluating their culture technique and/or sending the duodenoscope to the manufacturer for evaluation. †The levels of low-concern organisms on a duodenoscope may vary depending on the reprocessing, handling, and culturing practices in a facility. Therefore, the acceptable level of these organisms can vary. Facilities can monitor the levels of low-concern organisms during the first month of surveillance testing to develop an appropriate baseline for those organisms. Typically, fewer than 10 CFU of these microbes does not require intervention; interpretation of culture results with ≥ 10 CFU of non-pathogenic microbes should be considered in the context of expected culture results at the facility.