title: Peptide nucleic acid fluorescent in situ hybridization for hospital-acquired enterococcal bacteremia: delivering earlier effective antimicrobial therapy.
abstract: Hospital-acquired vancomycin-resistant enterococcal bacteremia has been associated with increased hospital costs, length of stay, and mortality. The peptide nucleic acid fluorescent in situ hybridization (PNA FISH) test for Enterococcus faecalis and other enterococci (EFOE) is a multicolor probe that differentiates E. faecalis from other enterococcal species within 3 h directly from blood cultures demonstrating gram-positive cocci in pairs and chains (GPCPC). A quasiexperimental study was performed over two consecutive years beginning in 2005 that identified GPCPC by conventional microbiological methods, and in 2006 PNA FISH was added with a treatment algorithm developed by the antimicrobial team (AMT). The primary outcome assessed was the time from blood culture draw to the implementation of effective antimicrobial therapy before and after PNA FISH. The severity of illness, patient location, and empirical antimicrobial therapy were measured. A total of 224 patients with hospital-acquired enterococcal bacteremia were evaluated, with 129 in the preintervention period and 95 in the PNA FISH period. PNA FISH identified E. faecalis 3 days earlier than conventional cultures (1.1 versus 4.1 days; P < 0.001). PNA FISH identified Enterococcus faecium a median 2.3 days earlier (1.1 versus 3.4 days; P < 0.001) and was associated with statistically significant reductions in the time to initiating effective therapy (1.3 versus 3.1 days; P < 0.001) and decreased 30-day mortality (26% versus 45%; P = 0.04). The EFOE PNA FISH test in conjunction with an AMT treatment algorithm resulted in earlier initiation of appropriate empirical antimicrobial therapy for patients with hospital-acquired E. faecium bacteremia.
authors.affiliation: Division of Infectious Diseases, University of Maryland School of Medicine, Baltimore, Maryland, USA. forrestg@ohsu.edu
authors.forename: Graeme N
authors.initials: GN
authors.lastname: Forrest
authors.forename: Mary-Claire
authors.initials: MC
authors.lastname: Roghmann
authors.forename: Latoya S
authors.initials: LS
authors.lastname: Toombs
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Johnson
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Weekes
authors.forename: Durry P
authors.initials: DP
authors.lastname: Lincalis
authors.forename: Richard A
authors.initials: RA
authors.lastname: Venezia
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D016470:Bacteremia / Q000188:drug therapy* / Q000382:microbiology*; D003428:Cross Infection / Q000188:drug therapy* / Q000382:microbiology*; D013293:Enterococcus faecalis / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D016984:Enterococcus faecium / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015335:Molecular Probes / Q000235:genetics; D020135:Peptide Nucleic Acids / Q000235:genetics*; D013997:Time Factors; D020713:Vancomycin Resistance / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D015335:Molecular Probes; D020135:Peptide Nucleic Acids