title: Impact of antimicrobial stewardship intervention on coagulase-negative Staphylococcus blood cultures in conjunction with rapid diagnostic testing.
abstract: Rapid diagnostic testing with matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) decreases the time to organism identification by 24 to 36 h compared to the amount of time required by conventional methods. However, there are limited data evaluating the impact of MALDI-TOF with real-time antimicrobial stewardship team (AST) review and intervention on antimicrobial prescribing and outcomes for patients with bacteremia and blood cultures contaminated with coagulase-negative Staphylococcus (CoNS). A quasiexperimental study was conducted to analyze the impact of rapid diagnostic testing with MALDI-TOF plus AST review and intervention for adult hospitalized patients with blood cultures positive for CoNS. Antibiotic prescribing patterns and clinical outcomes were compared before and after implementation of MALDI-TOF with AST intervention for patients with CoNS bacteremia and CoNS contamination. A total of 324 patients with a positive CoNS blood culture were included; 246 were deemed to have contaminated cultures (117 in the preintervention group and 129 in AST the intervention group), and 78 patients had bacteremia (46 in the preintervention group and 32 in the AST intervention group). No differences in demographics were seen between the groups, and similar rates of contamination occurred between the preintervention and AST intervention groups (64.3% versus 72.6%, P = 0.173). Patients with bacteremia were initiated on optimal therapy sooner in the AST intervention group (58.7 versus 34.4 h, P = 0.030), which was associated with a similarly decreased mortality (21.7% versus 3.1%, P = 0.023). Patients with CoNS-contaminated cultures had similar rates of mortality, lengths of hospitalization, recurrent bloodstream infections, and 30-day hospital readmissions, but the AST intervention group had a decreased duration of unnecessary antibiotic therapy (1.31 versus 3.89 days, P = 0.032) and a decreased number of vancomycin trough assays performed (0.88 versus 1.95, P < 0.001). In patients with CoNS bacteremia, rapid pathogen identification integrated with real-time stewardship interventions improved timely organism identification and initiation of antibiotic therapy. Patients in the AST group with blood cultures contaminated with CoNS had decreased inappropriate antimicrobial prescribing and decreased unnecessary serum vancomycin trough assays.
authors.affiliation: Department of Pharmacy Services and Clinical Sciences, University of Michigan Health System and College of Pharmacy, Ann Arbor, Michigan, USA nageljl@med.umich.edu.
authors.forename: Jerod L
authors.initials: JL
authors.lastname: Nagel
authors.affiliation: Department of Pharmacy Services and Clinical Sciences, University of Michigan Health System and College of Pharmacy, Ann Arbor, Michigan, USA Froedtert Hosptial and The Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
authors.forename: Angela M
authors.initials: AM
authors.lastname: Huang
authors.affiliation: Department of Pharmacy Services and Clinical Sciences, University of Michigan Health System and College of Pharmacy, Ann Arbor, Michigan, USA.
authors.forename: Anjly
authors.initials: A
authors.lastname: Kunapuli
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, University of Michigan Health System and Medical School, Ann Arbor, Michigan, USA.
authors.forename: Tejal N
authors.initials: TN
authors.lastname: Gandhi
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, University of Michigan Health System and Medical School, Ann Arbor, Michigan, USA Department of Infection Control and Epidemiology, University of Michigan Health System and Medical School, Ann Arbor, Michigan, USA.
authors.forename: Laraine L
authors.initials: LL
authors.lastname: Washer
authors.affiliation: Department of Pharmacy Services and Clinical Sciences, University of Michigan Health System and College of Pharmacy, Ann Arbor, Michigan, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Lassiter
authors.affiliation: Department of Pharmacy Services and Clinical Sciences, University of Michigan Health System and College of Pharmacy, Ann Arbor, Michigan, USA.
authors.forename: Twisha
authors.initials: T
authors.lastname: Patel
authors.affiliation: Clinical Microbiology Laboratories and Department of Pathology, University of Michigan Health System and Medical School, Ann Arbor, Michigan, USA.
authors.forename: Duane W
authors.initials: DW
authors.lastname: Newton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology*; D001431:Bacteriological Techniques / Q000379:methods*; D003030:Coagulase / Q000172:deficiency; D004363:Drug Utilization / Q000592:standards*; D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology*; D013210:Staphylococcus / Q000187:drug effects* / Q000302:isolation & purification; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D003030:Coagulase