title: Factors influencing the development of antibiotic associated diarrhea in ED patients discharged home: risk of administering IV antibiotics.
abstract: OBJECTIVE
  Antibiotic-associated diarrhea (AAD) and Clostridium difficile infection (CDI) are well-known outcomes from antibiotic administration. Because emergency department (ED) visits frequently result in antibiotic use, we evaluated the frequency of AAD/CDI in adults treated and discharged home with new prescriptions for antibiotics to identify risk factors for acquiring AAD/CDI.
  
  
  METHODS
  This prospective multicenter cohort study enrolled adult patients who received antibiotics in the ED and were discharged with a new prescription for antibiotics. Antibiotic-associated diarrhea was defined as 3 or more loose stools for 2 days or more within 30 days of starting the antibiotic. C difficile infection was defined by the detection of toxin A or B within this same period. We used multivariate logistic regression to assess predictors of developing AAD.
  
  
  RESULTS
  We enrolled and followed 247 patients; 45 (18%) developed AAD, and 2 (1%) developed CDI. Patients who received intravenous (IV) antibiotics in the ED were more likely to develop AAD/CDI than patients who did not: 25.7% (95% confidence interval [CI], 17.4-34.0) vs 12.3% (95% CI, 6.8-17.9). Intravenous antibiotics had adjusted odds ratio of 2.73 (95% CI, 1.38-5.43), and Hispanic ethnicity had adjusted odds ratio of 3.04 (95% CI, 1.40-6.58). Both patients with CDI had received IV doses of broad-spectrum antibiotics.
  
  
  CONCLUSIONS
  Intravenous antibiotic therapy administered to ED patients before discharge was associated with higher rates of AAD and with 2 cases of CDI. Care should be taken when deciding to use broad-spectrum IV antibiotics to treat ED patients before discharge home.
authors.affiliation: Department of Emergency Medicine, University of Massachusetts Medical School, Worcester, MA. Electronic address: johnpharan@gmail.com.
authors.forename: John Patrick
authors.initials: JP
authors.lastname: Haran
authors.affiliation: Department of Emergency Medicine, Alpert Medical School of Brown University, Providence, RI.
authors.forename: Gregory
authors.initials: G
authors.lastname: Hayward
authors.affiliation: Department of Emergency Medicine, University of Massachusetts Medical School, Worcester, MA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Skinner
authors.affiliation: Department of Emergency Medicine, Alpert Medical School of Brown University, Providence, RI.
authors.forename: Chris
authors.initials: C
authors.lastname: Merritt
authors.affiliation: Division of Biostatistics and Health Services Research, Department of Quantitative Health Sciences, University of Massachusetts Medical School, Worcester, MA.
authors.forename: David C
authors.initials: DC
authors.lastname: Hoaglin
authors.affiliation: Department of Pediatrics and Division of Global Health, Harvard Medical School, Boston, MA.
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Hibberd
authors.affiliation: Laboratory of Nucleic Acid Vaccines, Department of Medicine, University of Massachusetts Medical School, Worcester, MA.
authors.forename: Shan
authors.initials: S
authors.lastname: Lu
authors.affiliation: Department of Emergency Medicine, University of Massachusetts Medical School, Worcester, MA.
authors.forename: Edward W
authors.initials: EW
authors.lastname: Boyer
mesh_terms: D061605:Administration, Intravenous / Q000706:statistics & numerical data*; D000284:Administration, Oral; D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D015331:Cohort Studies; D003967:Diarrhea / Q000139:chemically induced / Q000453:epidemiology* / Q000208:ethnology; D004636:Emergency Service, Hospital; D004761:Enterocolitis, Pseudomembranous / Q000453:epidemiology* / Q000208:ethnology / Q000209:etiology; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011446:Prospective Studies; D012307:Risk Factors; D044465:White People / Q000706:statistics & numerical data
chemical_list: D000900:Anti-Bacterial Agents