title: Comparison of bacteria isolated from emergency department patients versus hospitalized patients.
abstract: OBJECTIVE
  The frequencies and corresponding susceptibilities of bacteria isolated from patients in the emergency department (ED) were compared with those from hospitalized patients.
  
  
  METHODS
  A microbiology laboratory report of all positive bacterial cultures obtained in the ED, regardless of the source (e.g., blood, urine, sputum), was obtained. In the case of duplicate cultures, only the first isolate cultured from a single patient was included. Colonization-site cultures (e.g., nasal swabs) and culture reports identified by the laboratory as contaminant organisms were excluded from the evaluation. Antimicrobial susceptibility results were then compiled into a standardized ED-specific antibiogram. Antimicrobial susceptibilities for each pathogen in the ED antibiogram were compared with those in the hospitalwide antibiogram. If there was a difference of ≥5% between the susceptibility of a single antimicrobial agent, chi-square tests were conducted, and unadjusted odds ratios were calculated. Pathogens with fewer than 30 isolates were excluded from the susceptibility comparison.
  
  
  RESULTS
  A total of 3140 cultures were evaluated (1417 from the ED, 1723 from the hospital). The frequencies of pathogens isolated in the ED and hospitalwide were similar, with the exception of Escherichia coli, which were more commonly isolated in ED patients, and Enterococcus species and Pseudomonas aeruginosa, which were more common in hospitalized patients. Significant differences in susceptibility profiles were identified for Staphylococcus aureus, coagulase-negative Staphylococcus, Enterococcus faecalis, E. coli, Klebsiella pneumoniae, and P. aeruginosa.
  
  
  CONCLUSIONS
  Significant differences in the frequencies of bacteria isolated and corresponding susceptibilities were found in cultures obtained in ED patients compared with those obtained in hospitalized patients.
authors.affiliation: Heather M. Draper, Pharm.D., BCPS, is Associate Professor, Department of Clinical Pharmacy, University of Tennessee, Knoxville. Joseph B. Farland, Pharm.D., BCPS, is Pharmacist, Pharmacy Department, Blount Memorial Hospital, Maryville, TN. R. Eric Heidel, Ph.D., is Statistical and Research Design Consultant, University of Tennessee Graduate School of Medicine, Knoxville. Larissa S. May, M.D., M.S.P.H., is Associate Director of Clinical Research and Assistant Professor, Department of Emergency Medicine, George Washington University, Washington, DC. Katie J. Suda, Pharm.D., M.S., is Associate Professor, College of Pharmacy, University of Tennessee, Memphis.
authors.forename: Heather M
authors.initials: HM
authors.lastname: Draper
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Farland
authors.forename: R Eric
authors.initials: RE
authors.lastname: Heidel
authors.forename: Larissa S
authors.initials: LS
authors.lastname: May
authors.forename: Katie J
authors.initials: KJ
authors.lastname: Suda
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification*; D001424:Bacterial Infections / Q000188:drug therapy / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D004636:Emergency Service, Hospital; D006760:Hospitalization; D006801:Humans; D008826:Microbial Sensitivity Tests
chemical_list: D000900:Anti-Bacterial Agents