Impact of rapid diagnostic tests on the management of patients presenting with Enterobacteriaceae bacteremia

Med Mal Infect. 2019 May;49(3):202-207. doi: 10.1016/j.medmal.2018.11.015. Epub 2018 Dec 27.

Abstract

Objective: Pathogens are usually identified from blood cultures using a two-step procedure: Gram staining on the day of bacterial growth (D0), followed by identification and susceptibility testing the following day (D1). We aimed to evaluate the use of rapid tests performed on D0 in patients presenting with Enterobacteriaceae bacteremia.

Patients and methods: Patients with≥1 positive monomicrobial blood culture with Gram staining suggestive of an Enterobacteriaceae were prospectively included. Two successive strategies were evaluated: i) conventional strategy (CS), ii) combination of a rapid identification test and third-generation cephalosporin susceptibility testing (rapid strategy, e.g. RS).

Results: Eighty-three patients were included (CS=42; RS=41). Compared with CS, the median delay of identification was significantly shorter with RS (22 hours [20-27] vs. 47 hours [42-53]; P<0.001). Patients in the RS group more frequently received an effective (82.9% vs. 73.8%, P=0.43) and appropriate (70.7% vs. 54.7%, P=0.17) antibiotic therapy on D1. Moreover, all five RS patients infected with a non-susceptible strain received an effective therapy on D1 versus only three of eight CS patients.

Conclusions: Use of rapid testing was associated with a reduced time to result availability. This strategy should be useful to initiate an early effective and appropriate therapy and to improve the care of patients.

Keywords: Agents antibactériens; Antibacterial agents; Bacteremia; Bactériémie; Blood culture; Cephalosporins; Céphalosporines; Enterobacteriaceae; Entérobactérie; Hémoculture.

Publication types

  • Observational Study

MeSH terms

  • Aged
  • Aged, 80 and over
  • Bacteremia / diagnosis*
  • Bacteremia / epidemiology
  • Bacteremia / microbiology
  • Bacteremia / therapy*
  • Diagnostic Tests, Routine / methods*
  • Diagnostic Tests, Routine / statistics & numerical data
  • Early Medical Intervention / methods
  • Enterobacteriaceae / isolation & purification
  • Enterobacteriaceae Infections / diagnosis*
  • Enterobacteriaceae Infections / epidemiology
  • Enterobacteriaceae Infections / microbiology
  • Enterobacteriaceae Infections / therapy*
  • Female
  • Gentian Violet
  • Humans
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Phenazines
  • Sepsis / drug therapy
  • Sepsis / epidemiology
  • Sepsis / microbiology
  • Time Factors
  • Time-to-Treatment / statistics & numerical data

Substances

  • Gram's stain
  • Phenazines
  • Gentian Violet