title: Real-time PCR testing for mecA reduces vancomycin usage and length of hospitalization for patients infected with methicillin-sensitive staphylococci.
abstract: Nucleic acid amplification tests (NAATs) have revolutionized infectious disease diagnosis, allowing for the rapid and sensitive identification of pathogens in clinical specimens. Real-time PCR testing for the mecA gene (mecA PCR), which confers methicillin resistance in staphylococci, has the added potential to reduce antibiotic usage, improve clinical outcomes, lower health care costs, and avoid emergence of drug resistance. A retrospective study was performed to identify patients infected with methicillin-sensitive staphylococcal isolates who were receiving vancomycin treatment when susceptibility results became available. Vancomycin treatment and length of hospitalization were compared in these patients for a 6-month period before and after implementation of mecA PCR. Among 65 and 94 patients identified before and after mecA PCR, respectively, vancomycin usage (measured in days on therapy) declined from a median of 3 days (range, 1 to 44 days) in the pre-PCR period to 1 day (range, 0 to 18 days) in the post-PCR period (P < 0.0001). In total, 38.5% (25/65) of patients were switched to beta-lactam therapy in the pre-PCR period, compared to 61.7% (58/94) in the post-PCR period (P = 0.004). Patient hospitalization days also declined from a median of 8 days (range, 1 to 47 days) in the pre-PCR period to 5 days (range, 0 to 42 days) in the post-PCR period (P = 0.03). Real-time PCR testing for mecA is an effective tool for reducing vancomycin usage and length of stay of hospitalized patients infected with methicillin-sensitive staphylococci. In the face of ever-rising health care expenditures in the United States, these findings have important implications for improving outcomes and decreasing costs.
authors.affiliation: Department of Pathology, Stanford University School of Medicine, Stanford, California 94305, USA.
authors.forename: David T
authors.initials: DT
authors.lastname: Nguyen
authors.forename: Ellen
authors.initials: E
authors.lastname: Yeh
authors.forename: Sharon
authors.initials: S
authors.lastname: Perry
authors.forename: Robert F
authors.initials: RF
authors.lastname: Luo
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Pinsky
authors.forename: Betty P
authors.initials: BP
authors.lastname: Lee
authors.forename: Deepak
authors.initials: D
authors.lastname: Sisodiya
authors.forename: Ellen Jo
authors.initials: EJ
authors.lastname: Baron
authors.forename: Niaz
authors.initials: N
authors.lastname: Banaei
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001426:Bacterial Proteins / Q000235:genetics; D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests / Q000379:methods; D008875:Middle Aged; D046915:Penicillin-Binding Proteins; D016133:Polymerase Chain Reaction / Q000379:methods*; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics; D014481:United States; D014640:Vancomycin / Q000627:therapeutic use*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D046915:Penicillin-Binding Proteins; C487789:mecA protein, Staphylococcus aureus; D014640:Vancomycin