MALDI-TOF Technique Availability for Identification of Septic Agents in Pediatric Practice
The aim of the investigation was to assess MALDI-TOF mass spectrometry efficiency to identify microorganisms in small blood volumes (1–4 ml) in children with suspected septic conditions by comparing MALDI-TOF mass spectrometry findings with those of a classical microbiological study.
Materials and Methods. The subject of the research was blood of children with suspected septic conditions. For analysis we used blood cultures with microorganism growth recorded by BACTEC 9050. Pathogens isolated from blood culture were identified in two ways — by a classical microbiological study and MALDI-TOF mass spectrometry using α-cyano-4-hydroxycinnamic acid as a matrix. To compare the efficiency of two methods for blood infectious agent identification we applied a standard statistical method determining a concordance coefficient — Cohen's kappa.
Results. The findings of MALDI-TOF mass spectrometry used to identify microorganisms in blood cultures of children with bloodstream infections with one agent were compliant with those of a classical microbial study (Cohen's kappa is 0.96; p<0.001). MALDI-TOF mass spectrometry and classical microbial study findings in the analysis of polymicrobial cultures had low concordance (Cohen's kappa is 0.58; p>0.05).
Conclusion. MAlDI-TOF mass spectroscopy identification of bloodstream infection agents can be recommended as a complimentary diagnostic technique aimed at analysis time reduction.
- Silva E., Passos R.H.D., Ferri M.B., de Figueiredo L.F.P. Sepsis: from bench to bedside. Clinics 2008; 63(1): 109–120, http://dx.doi.org/10.1590/s1807-59322008000100019.
- Mayr F.B., Yende S., Angus D.C. Epidemiology of severe sepsis. Virulence 2014; 5(1): 4–11, http://dx.doi.org/10.4161/viru.27372.
- Angus D.C., Linde-Zwirble W.T., Lidicker J., Clermont G., Carcillo J., Pinsky M.R. Epidemiology of severe sepsis in the United States: analysis of incidence, outcome, and associated costs of care. Crit Care Med 2001; 29(7): 1303–1310, http://dx.doi.org/10.1097/00003246-200107000-00002.
- Bagirova N.S. Current state of bacteriemia diagnostics. Soprovoditel’naya terapiya v onkologii 2006; 3: 23–38.
- Chebotkevich V.N., Kaytandzhan E.I., Burylev V.V., Shchetinkina E.E. Modern laboratory diagnostic techniques of sepsis. Klinicheskaya mikrobiologiya i antimikrobnaya khimioteriya 2013; 15(4): 295–300.
- Jordana-Lluch E., Giménez M., Quesada MD, Ausina V., Martró E. Improving the diagnosis of bloodstream infections: PCR coupled with mass spectrometry. Biomed Res Int 2014; 2014: ID 501214, http://dx.doi.org/10.1155/2014/501214.
- Mayanskiy N.A., Kalakutskaya A.N., Motuzova O.V., Lominadze G.G., Kryzhanovskaya O.A., Katosova L.K. MALDI-TOF mass spectrometry in the clinical microbiology laboratory everyday work. Voprosy diagnostiki v pediatrii 2011; 3(5): 20–25.
- Tadros M., Petrich A. Evaluation of MALDI-TOF mass spectrometry and Sepsityper Kit™ for the direct identification of organisms from sterile body fluids in a Canadian Pediatric Hospital. Can J Infect Dis Med Microbiol 2013; 24(4): 191–194.
- Tsai M.H., Chu S.M., Hsu J.F., Lien R., Huang H.R., Chiang M.C., Fu R.H., Lee C.W., Huang Y.C. Polymicrobial bloodstream infection in neonates: microbiology, clinical characteristics, and risk factors. PLoS One 2014; 9(1): e83082, http://dx.doi.org/10.1371/journal.pone.0083082.
- Gray T.J., Thomas L., Olma T., Iredell J.R., Chen S.C. Rapid identification of Gram-negative organisms from blood culture bottles using a modified extraction method and MALDI-TOF mass spectrometry. Diagn Microbiol Infect Dis 2013; 77(2): 110–112, http://dx.doi.org/10.1016/j.diagmicrobio.2013.06.016.
- Kryzhanovskaya O.A., Lazareva A.V., Ponomarenko O.A., Katosova L.K., Tepaev R.F., Karaseva O.V., Chebotar I.V. Mass spectrometric identification of causative pathogens of bloodstream infections: experience in pediatric practice. Rossiyskiy pediatricheskiy zhurnal 2014; 17(5): 4–9.
- Fleiss J.L., Levin B., Paik M.C. Statistical methods for rates and proportions. New York: John Wiley & Sons, Inc.; 2003, http://dx.doi.org/10.1002/0471445428.
- Priputnevich T.V., Melkumyan A.R., Burmenskaya O.V., Nepsha O.S., Nikitina I.V., Lyubasovskaya L.A., Ionov O.V., Ilyina E.N., Trofimov D.Yu., Mitrokhin S.D. Use of MALDI-TOF mass spectrometry and quantitative PCR for rapid diagnosis of sepsis. Klinicheskaya mikrobiologiya i antimikrobnaya khimioterapiya 2014; 16(1): 4–9.
- La Scola B. Intact cell MALDI-TOF mass spectrometry-based approaches for the diagnosis of bloodstream infections. Expert Rev Mol Diagn 2011; 11(3): 287–298.