title: Identification of pathogens from blood culture bottles in spiked and clinical samples using matrix-assisted laser desorption ionization time-of-flight mass-spectrometry analysis.
abstract: BACKGROUND
  Blood stream infections significantly contribute to mortality. An early most appropriate antimicrobial therapy is crucial for a favourable outcome of the patient. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) may speed up the diagnostic of causative micro organisms.
  
  
  RESULTS
  MALDI-TOF MS using the SARAMIS database was applied to 37 spiked blood culture samples. Identification rates of spiked samples were as follows: The species level was determined in 16 of 21 (76.2%) Gram negative bacteria and in 11 of 13 (84.6%) Gram positive bacteria. Genus level only was determined in additional 2 Gram negative and for the 2 Gram positive strains. Yeast species could not be identified.MALDI-TOF MS was also compared to cultured-based results in standard routine diagnostic. Identification rates of patient samples were as follows: The species level was determined in 41 of 47 (87.2%) Gram negative bacteria and in 63 of 123 (51.2%) Gram positive bacteria. Genus level only was determined in additional 2 Gram negative bacteria. Once again no yeasts were identified.A prolonged incubation of BC bottles for 16 hours after primary positive alert did not influence the concentration of bacteria and identification rates.
  
  
  CONCLUSIONS
  The SARAMIS database used in our experiments mainly confirms previous findings that were obtained with the MALDI-TOF MS BRUKER system by others.
authors: Simone
authors: S
authors: Konnerth
authors: Gisela
authors: G
authors: Rademacher
authors: Sebastian
authors: S
authors: Suerbaum
authors: Stefan
authors: S
authors: Ziesing
authors: Ludwig
authors: L
authors: Sedlacek
authors: Institute for Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Str, 1, D-30625 Hannover, Germany. Vonberg.Ralf@MH-Hannover.DE.
authors: Ralf-Peter
authors: RP
authors: Vonberg
mesh_terms: D016470:Bacteremia / Q000175:diagnosis* / Q000382:microbiology; D015373:Bacterial Typing Techniques / Q000379:methods*; D016208:Databases, Factual; D006090:Gram-Negative Bacteria / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000302:isolation & purification*; D006801:Humans; D018805:Sepsis / Q000175:diagnosis* / Q000382:microbiology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization