PCR-reverse blot hybridization assay for screening and identification of pathogens in sepsis

J Clin Microbiol. 2013 May;51(5):1451-7. doi: 10.1128/JCM.01665-12. Epub 2013 Feb 27.

Abstract

Rapid and accurate identification of the pathogens involved in bloodstream infections is crucial for the prompt initiation of appropriate therapy, as this can decrease morbidity and mortality rates. A PCR-reverse blot hybridization assay for sepsis, the reverse blot hybridization assay (REBA) Sepsis-ID test, was developed; it uses pan-probes to distinguish Gram-positive and -negative bacteria and fungi. In addition, the assay was designed to identify bacteria and fungi using six genus-specific and 13 species-specific probes; it uses additional probes for antibiotic resistance genes, i.e., the mecA gene of methicillin-resistant Staphylococcus aureus (MRSA) and the vanA and vanB genes of vancomycin-resistant enterococci (VRE). The REBA Sepsis-ID test successfully identified clinical isolates and blood culture samples as containing Gram-positive bacteria, Gram-negative bacteria, or fungi. The results matched those obtained with conventional microbiological methods. For the REBA Sepsis-ID test, of the 115 blood culture samples tested, 47 (40.8%) and 49 (42.6%) samples were identified to the species and genus levels, respectively, and the remaining 19 samples (16.5%), which included five Gram-positive rods, were identified as Gram-positive bacteria, Gram-negative bacteria, or fungi. The antibiotic resistances of the MRSA and VRE strains were identified using both conventional microbiological methods and the REBA Sepsis-ID test. In conclusion, the REBA Sepsis-ID test developed for this study is a fast and reliable test for the identification of Gram-positive bacteria, Gram-negative bacteria, fungi, and antibiotic resistance genes (including mecA for MRSA and the vanA and vanB genes for VRE) in bloodstream infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria* / classification
  • Bacteria* / genetics
  • Bacteria* / isolation & purification
  • Bacterial Infections / diagnosis*
  • Bacterial Proteins / genetics
  • Carbon-Oxygen Ligases / genetics
  • Drug Resistance, Multiple, Bacterial / genetics
  • Fungi* / classification
  • Fungi* / genetics
  • Fungi* / isolation & purification
  • Humans
  • Microbial Sensitivity Tests
  • Mycoses / diagnosis*
  • Penicillin-Binding Proteins
  • Polymerase Chain Reaction
  • Reagent Kits, Diagnostic
  • Sepsis / diagnosis
  • Sepsis / microbiology*

Substances

  • Bacterial Proteins
  • Penicillin-Binding Proteins
  • Reagent Kits, Diagnostic
  • VanA ligase, Bacteria
  • VanB protein, Enterococcus
  • mecA protein, Staphylococcus aureus
  • Carbon-Oxygen Ligases