CHROMagar™ orientation urine culture medium produces matrix-assisted laser desorption ionization-time-of-flight mass spectrometry spectra misidentified as Mycoplasma arginini and Mycoplasma alkalescens

Diagn Microbiol Infect Dis. 2019 Jun;94(2):113-115. doi: 10.1016/j.diagmicrobio.2018.12.014. Epub 2019 Jan 2.

Abstract

Matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry is commonly used to identify bacteria and yeasts. Studies indicate that MALDI-TOF is relatively indifferent to the medium used for culture. We report on an investigation into high- and low-confidence MALDI-TOF misidentifications of Mycoplasma arginini and Mycoplasma alkalescens from urine specimens plated to CHROMagar™ Orientation medium that appear to be due to the intrinsic mass spectrum of the medium.

Keywords: Chromogenic; Culture; Identification; MALDI-TOF; Mass spectrometry; Mycoplasma; Urine.

MeSH terms

  • Culture Media / chemistry*
  • Diagnostic Errors*
  • Humans
  • Mycoplasma / chemistry
  • Mycoplasma / isolation & purification*
  • Mycoplasma Infections / diagnosis*
  • Mycoplasma Infections / microbiology
  • Specimen Handling / methods*
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods*
  • Urinary Tract Infections / diagnosis
  • Urinary Tract Infections / microbiology
  • Urine / microbiology*

Substances

  • Culture Media