Detection of an emerging pathogen: A real time qualitative pcr assay targeting Haematospirillum jordaniae for EDTA whole blood and plasma clinical specimens

Diagn Microbiol Infect Dis. 2024 Aug;109(4):116310. doi: 10.1016/j.diagmicrobio.2024.116310. Epub 2024 Apr 24.

Abstract

Haematospirillum jordaniae is a gram-negative bacterium that has been identified in the blood of septic patients. The environmental source or potential zoonotic host of this bacterium, recently described as a human bacterial pathogen is unknown. An increasing number of H. jordaniae clinical infections identified by our laboratory suggested the need for an assay to detect this organism in order to aid clinical teams and practitioners with faster identification and treatment thus improving patient prognosis. Described here is a real-time qualitative PCR assay designed using gene targets identified from the analysis of 14 H. jordaniae genomes sequenced by the Center for Disease Control and Prevention's (CDC) Special Bacterial Reference Laboratory (SBRL) culture collection. The assay was validated on clinical EDTA whole blood samples as well as on plasma and determined to be effective at detecting as few as 10 copies per microliter (10,000 copies per mL, 4 log/mL) for whole blood samples and 1 copy per microliter (1,000 copies per mL, 3 log mL) for plasma samples.

Keywords: Bacteria; Blood; Clinical microbiology; GRAM-negative; Haematospirillum jordaniae; Molecular diagnostics; Pathogen; Real-time polymerase chain reaction.

MeSH terms

  • Blood / microbiology
  • DNA, Bacterial / blood
  • DNA, Bacterial / genetics
  • Edetic Acid
  • Gram-Negative Bacterial Infections* / blood
  • Gram-Negative Bacterial Infections* / diagnosis
  • Gram-Negative Bacterial Infections* / microbiology
  • Humans
  • Plasma / microbiology
  • Real-Time Polymerase Chain Reaction* / methods
  • Sensitivity and Specificity

Substances

  • Edetic Acid
  • DNA, Bacterial