Utility of Acridine Orange staining for detection of bacteria from positive blood cultures

J Microbiol Methods. 2017 Aug:139:215-217. doi: 10.1016/j.mimet.2017.06.014. Epub 2017 Jun 15.

Abstract

The diagnostic performance of AO stain was evaluated for the detection of bacteria and or fungi from positive blood cultures. The sensitivity of Gram stain (GS) was 98.26% while Acridine Orange (AO) stain proved to be more sensitive (100%) with a Positive and Negative Predictive Value of 100% each. The specificity of both the stains was 100%. Overall agreement between the two stains was 98.23% (688/700). The organisms that were missed by GS and positive by AO were Candida species (Sutton, 2006) and Gram negative bacilli (GNB) (Sutton, 2006). Sensitivity of GS was 82.35% and AO was 100% among mixed cultures. Immediate reporting of the results of AO stain would have a significant impact on clinical management of patients with serious blood stream infections.

Keywords: Gram negative bacilli; Gram stain; Sensitivity; Specificity; Yeast.

MeSH terms

  • Acridine Orange*
  • Bacteremia / diagnosis
  • Bacteremia / microbiology*
  • Bacteria / isolation & purification*
  • Blood Culture* / standards
  • Coloring Agents* / chemistry
  • Gentian Violet
  • Gram-Negative Bacteria / isolation & purification
  • Gram-Negative Bacteria / metabolism
  • Humans
  • Phenazines
  • Sensitivity and Specificity
  • Staining and Labeling / economics
  • Yeasts / isolation & purification
  • Yeasts / metabolism

Substances

  • Coloring Agents
  • Gram's stain
  • Phenazines
  • Acridine Orange
  • Gentian Violet