The prevalence of resistant Gram-negative bacteraemia among hospitalized patients in Tucson, Arizona over a 12-month period; A retrospective single center study

J Int Med Res. 2020 Jan;48(1):300060519829987. doi: 10.1177/0300060519829987. Epub 2019 Feb 20.

Abstract

Introduction: The objectives of this retrospective review were to: (a) determine the prevalence of resistant Gram-negative bacteraemia among hospitalized patients; (b) evaluate antibiotic use; (c) determine the time taken for Gram staining to final species identification.

Methods: For this retrospective study, information was extracted from patients’ electronic medical records. Eligible patients had been admitted to a 300-bed tertiary care hospital in Tucson, Arizona from October 2015 to October 2016, were over 18 years of age and had a positive blood culture for Gram-negative bacteraemia.

Results: In total, 84 patients with Gram-negative bacteraemia were identified; urinary tract infection was the most common source of infection (71%). ESBL-producing microorganisms were isolated from five (6%) patients and no MDR pathogens were identified. The, median time to Gram stain was 20.5 hours and the median time to final identification was 54.5 hours. Delayed de-escalation of broad-spectrum antibiotics (i.e., >24 hours after final culture) occurred in 25% patients with a median length of hospital stay of 118 hours (range: 56–552 hours) compared with a median length of hospital stay of 89 hours (range: 5–334 hours) in the early de-escalation group.

Conclusion: The prevalence of bacteraemia due to resistant Gram-negative microorganisms is low (6%) in this institution. However, there may be room for improvement in the antimicrobial stewardship program with regard to rapid diagnostic testing.

Keywords: Bacteraemia; Gram-negative; bloodstream infections; extended-spectrum beta-lactamases; multidrug resistance.

MeSH terms

  • Aged
  • Arizona / epidemiology
  • Bacteremia / epidemiology*
  • Bacteremia / microbiology*
  • Female
  • Gram-Negative Bacteria / isolation & purification
  • Gram-Negative Bacteria / physiology*
  • Gram-Negative Bacterial Infections / epidemiology*
  • Hospitalization*
  • Humans
  • Male
  • Prevalence
  • Retrospective Studies
  • beta-Lactamases / metabolism

Substances

  • beta-Lactamases