title: PCR-electrospray ionization mass spectrometry for direct detection of pathogens and antimicrobial resistance from heart valves in patients with infective endocarditis.
abstract: Microbiological diagnosis is pivotal to the appropriate management and treatment of infective endocarditis. We evaluated PCR-electrospray ionization mass spectrometry (PCR/ESI-MS) for bacterial and candidal detection using 83 formalin-fixed paraffin-embedded heart valves from subjects with endocarditis who had positive valve and/or blood cultures, 63 of whom had positive valvular Gram stains. PCR/ESI-MS yielded 55% positivity with concordant microbiology at the genus/species or organism group level (e.g., viridans group streptococci), 11% positivity with discordant microbiology, and 34% with no detection. PCR/ESI-MS detected all antimicrobial resistance encoded by mecA or vanA/B and identified a case of Tropheryma whipplei endocarditis not previously recognized.
authors.affiliation: Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Cassandra L
authors.initials: CL
authors.lastname: Brinkman
authors.forename: Paschalis
authors.initials: P
authors.lastname: Vergidis
authors.forename: James R
authors.initials: JR
authors.lastname: Uhl
authors.forename: Bobbi S
authors.initials: BS
authors.lastname: Pritt
authors.forename: Franklin R
authors.initials: FR
authors.lastname: Cockerill
authors.forename: James M
authors.initials: JM
authors.lastname: Steckelberg
authors.forename: Larry M
authors.initials: LM
authors.lastname: Baddour
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Maleszewski
authors.forename: William D
authors.initials: WD
authors.lastname: Edwards
authors.forename: Rangarajan
authors.initials: R
authors.lastname: Sampath
authors.forename: Robin
authors.initials: R
authors.lastname: Patel
mesh_terms: D001419:Bacteria / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D002175:Candida / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D024881:Drug Resistance, Bacterial; D025141:Drug Resistance, Fungal; D004696:Endocarditis / Q000175:diagnosis* / Q000382:microbiology; D005260:Female; D006351:Heart Valves / Q000382:microbiology*; D006801:Humans; D008297:Male; D008828:Microbiological Techniques / Q000379:methods*; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques / Q000379:methods; D016133:Polymerase Chain Reaction / Q000379:methods*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*