3202-B - C. Difficile: Are You Reviewing Non-labid Cases?

Session Description: In 2021, our institution’s microbiology laboratory adjusted our system wide Clostridioides difficile testing algorithm to a two-step process: polymerase chain reaction (PCR) testing followed by a reflex enzyme immunoassay (EIA) toxin test for positive PCR results in all C. difficile testing orders. Following this two-step process, tests with positive PCR and EIA toxin results are considered laboratory-identified (LabID) C. difficile events and are reported to the National Healthcare Safety Network (NHSN). Tests with a positive PCR result but a negative EIA toxin result would be considered a non-LabID event and not reportable to NHSN. Prior to this implementation, our system offered two separate options for C. difficile testing, including a PCR-based multiplex gastrointestinal panel and a stand-alone EIA antigen/toxin test with a reflex PCR component for discordant results. The updated testing algorithm streamlined diagnostic components across both test options and resulted in a significant decrease in hospital-onset, LabID C. difficile events. Although we experienced a favorable trend in reportable LabID events, we continued to abstract clinical data and information for all C. difficile tests with positive PCR results, regardless of whether the test met the LabID criteria as defined by NHSN. Based on the information abstracted, the majority of the opportunities we identified for improving testing stewardship occurred in our non-reportable C. difficile events. Analysis of reportable as well as non-reportable testing results enabled our system to more accurately identify testing stewardship opportunities that would remain unknown if we abstracted information for reportable LabID events alone. The additional information we obtained was used to direct accurate and valuable information to clinicians in order to continue improving overall testing stewardship and C. difficile reduction efforts. This improvement, along with our existing environmental controls, will position our institution to make continuous improvements in reducing hospital-onset C. difficile infections for years to come.