203. When rapid molecular blood culture testing fails to identify the organism: microbiology and patient outcomes


 
 
 Verigene™ is a rapid nucleic acid test used to optimize antibiotic selection on positive blood cultures but it does not detect all pathogens. The purpose of this project was to describe the organisms Verigene™ could not identify as well as the clinical outcomes of the patients.
 
 
 
 This was a single-center, retrospective cohort study of patients who received a Verigene™ non-detected result from 5/19/20-6/30/21. The primary objective of this study was to identify the organisms and secondary objectives included any changes in antimicrobial therapy after the test result, appropriateness of change in therapy, discharge disposition, and 30-day readmission rate.
 
 
 
 A total of 85 of 958 (8.9%) Verigene results were non-detected during the time period. Among the 85 results included for the primary objective, six were determined to be contaminants by the clinicians. Among the remaining 79 results, 44 were anaerobic bacteria, 11 Serratia species, and 24 were other miscellaneous bacteria. Therapy was changed in 62 (78.5%) after the Verigene result. Overall antibiotic regimens were deemed appropriate after antibiotic changes were made from the final culture result in 70 of 79 (88.6%) cases. Twenty five of 79 (31.6%) patients died in the hospital. Among the 54 patients discharged, 11 (20.3%) were readmitted within 30 days including five (9.2%) due to infection. No cases of infectious readmission were due to the prior episode of bacteremia.
 
 
 
 The majority of Verigene results that were not able to be identified were later identified to be anaerobic bacteria and Serratia species which are known limitations of the test. While most patients received appropriate therapy, there was a high mortality and readmission rate. Further studies should be performed to confirm this observation.
 
 
 
 All Authors: No reported disclosures.
