Rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) is essential for proper initial antibiotic therapy and timely set up of hygienic measures. Recently, detection of MRSA using MALDI-TOF mass spectrometer mediated by the peptide-phenol-soluble modulin (PSM-mec)-linked to the class A mec gene complex present in SCCmec cassettes types II, III, and VIII of MRSA strains, has been commercially available. We present here a multicentre study on MALDI-TOF MS detection of MRSA evincing a poor repeatability and reproducibility of the assay. The sensitivity of the assay varies between 50 and 90% in strains carrying psmMEC and psmδ genes encoding for PSM-mec and δ-toxin (a member of the PSM peptide family), respectively. No false positive results were found. The very major error calculation was 30% and the major error achieved 0%. Interlaboratory repeatability varies between 0 and 100%. No significant difference was observed with the use of different cultivation media. Our data showed a poor sensitivity of the method excluding it from the use in routine laboratory testing.

Biomedical Center Faculty of Medicine Charles University Pilsen Czech Republic

Department of Clinical Microbiology University Hospital and Faculty of Medicine in Hradec Kralove Charles University Hradec Kralove Czech Republic

Department of Microbiology Faculty of Medicine and University Hospital in Pilsen Charles University Pilsen Czech Republic

Department of Microbiology University Hospital of Larissa Larissa Greece

National Reference Laboratory for Antibiotics National Institute of Public Health Prague Czech Republic

Zobrazit více v PubMed

Ballhausen B, Kriegeskorte A, Schleimer N, Peters G, Becker K (2014) The mecA homolog mecC confers resistance against β-lactams in Staphylococcus aureus irrespective of the genetic strain background. Antimicrob Agents Chemother 58:3791–3798 DOI

Chatterjee SS, Chen L, Joo HS, Cheung GYC, Kreiswirth BN, Otto M (2011) Distribution and regulation of the mobile genetic element-encoded phenol-soluble modulin PSM-mec in methicillin-resistant Staphylococcus aureus. PLoS One 6:e28781 DOI

de Kraker MEA, Davey PG, Grundmann H (2011) Mortality and hospital stay associated with resistant Staphylococcus aureus and Escherichia coli bacteremia: estimating the burden of antibiotic resistance in Europe. PLoS Med 8:e1001104 DOI

Du Z, Yang R, Guo Z, Song Y, Wang J (2002) Identification of Staphylococcus aureus and determination of its methicillin resistance by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Anal Chem 74:5487–5491 DOI

Edwards-Jones V, Claydon MA, Evason DJ, Walker J, Fox AJ, Gordon DB (2000) Rapid discrimination between methicillin-sensitive and methicillin-resistant Staphylococcus aureus by intact cell mass spectrometry. J Med Microbiol 49:295–300 DOI

European Committee on Antimicrobial Susceptibility Testing (EUCAST) (2017) EUCAST guidelines for detection of resistance mechanisms and specific resistances of clinical and/or epidemiological importance, Version 2.0. Available at http://www.eucast.org/fileadmin/src/media/PDFs/EUCAST_files/Resistance_mechanisms/EUCAST_detection_of_resistance_mechanisms_170711.pdf

Fedorko DP, Stock F, Murray PR, Drake SK (2012) Identification of clinical isolates of anaerobic bacteria using matrix-assisted laser desorption ionization-time of flight mass spectrometry. Eur J Clin Microbiol Infect Dis 31:2257–2262 DOI

Gagnaire J, Dauwalder O, Boisset S, Khau D, Freydière AM, Ader F, Bes M, Lina G, Tristan A, Reverdy ME, Marchand A, Geissmann T, Benito Y, Durand G, Charrier JP, Etienne J, Welker M, Van Belkum A, Vandenesch F (2012) Detection of Staphylococcus aureus delta-toxin production by whole-cell MALDI-TOF mass spectrometry. PLoS One 7:e40660 DOI

García-Álvarez L, Holden MTG, Lindsay H, Webb CR, Brown DFJ, Curran MD, Walpole E, Brooks K, Pickard DJ, Teale C, Parkhill J, Bentley SD, Edwards GF, Girvan EK, Kearns AM, Pichon B, Hill RLR, Larsen AR, Skov RL, Peacock SJ, Maskell DJ, Holmes MA (2011) Meticillin-resistant Staphylococcus aureus with a novel mecA homologue in human and bovine populations in the UK and Denmark: a descriptive study. Lancet Infect Dis 11:595–603 DOI

Hanssen AM, Ericson Sollid JU (2006) SCCmec in staphylococci: genes on the move. FEMS Immunol Med Microbiol 46:8–20 DOI

Hrabák J, Chudacková E, Walková R (2013) Matrix-assisted laser desorption ionization-time of flight (MALDITOF) mass spectrometry for detection of antibiotic resistance mechanisms: from research to routine diagnosis. Clin Microbiol Rev 26:103–114 DOI

Jackson KA, Edwards-Jones V, Sutton CW, Fox AJ (2005) Optimisation of intact cell MALDI method for fingerprinting of methicillin-resistant Staphylococcus aureus. J Microbiol Methods 62:273–284 DOI

Jang KS, Park M, Lee JY, Kim JS (2017) Mass spectrometric identification of phenol-soluble modulins in the ATCC® 43300 standard strain of methicillin-resistant Staphylococcus aureus harboring two distinct phenotypes. Eur J Clin Microbiol Infect Dis 36:1151–1157 DOI

Josten M, Dischinger J, Szekat C, Reif M, Al-Sabti N, Sahl HG, Parcina M, Bekeredjian-Ding I, Bierbaum G (2014) Identification of agr-positive methicillin-resistant Staphylococcus aureus harbouring the class a mec complex by MALDI-TOF mass spectrometry. Int J Med Microbiol 304:1018–1023 DOI

Kretschmer D, Gleske AK, Rautenberg M, Wang R, Köberle M, Bohn E, Schöneberg T, Rabiet MJ, Boulay F, Klebanoff SJ, Van Kessel KA, Van Strijp JA, Otto M, Peschel A (2010) Human formyl peptide receptor 2 senses highly pathogenic Staphylococcus aureus. Cell Host Microbe 7:463–473 DOI

Lagacé-Wiens PRS, Adam HJ, Karlowsky JA, Nichol KA, Pang PF, Guenther J, Webb AA, Miller C, Alfa MJ (2012) Identification of blood culture isolates directly from positive blood cultures by use of matrix-assisted laser desorption ionization-time of flight mass spectrometry and a commercial extraction system: analysis of performance, cost, and turnaround time. J Clin Microbiol 50:3324–3328 DOI

Lakhundi S, Zhang K (2018) Methicillin-resistant Staphylococcus aureus: molecular characterization, evolution, and epidemiology. Clin Microbiol Rev 12:e00020–e00018

Liu J, Chen D, Peters BM, Li L, Li B, Xu Z, Shirliff ME (2016) Staphylococcal chromosomal cassettes mec (SCCmec): a mobile genetic element in methicillin-resistant Staphylococcus aureus. Microb Pathog 101:56–67 DOI

Majcherczyk PA, McKenna T, Moreillon P, Vaudaux P (2006) The discriminatory power of MALDI-TOF mass spectrometry to differentiate between isogenic teicoplanin-susceptible and teicoplanin-resistant strains of methicillin-resistant Staphylococcus aureus. FEMS Microbiol Lett 255:233–239 DOI

Marshall C, Kossmann T, Wesselingh S, Spelman D (2004) Methicillin-resistant Staphylococcus aureus and beyond: What's new in the world of the 'golden staph'? ANZ J Surg 74:465–469 DOI

Novick RP, Schlievert P, Ruzin A (2001) Pathogenicity and resistance islands of staphylococci. Microbes Infect 3:585–594 DOI

Otto M (2014) Phenol-soluble modulins. Int J Med Microbiol 304:164–169 DOI

Purrello SM, Garau J, Giamarellos E, Mazzei T, Pea F, Soriano A, Stefani S (2016) Methicillin-resistant Staphylococcus aureus infections: a review of the currently available treatment options. J Glob Antimicrob Resist 7:178–186 DOI

Rhoads DD, Wang H, Karichu J, Richter SS (2016) The presence of a single MALDI-TOF mass spectral peak predicts methicillin resistance in staphylococci. Diagn Microbiol Infect Dis 86:257–261 DOI

Rozgonyi F, Kocsis E, Kristóf K, Nagy K (2007) Is MRSA more virulent than MSSA? Clin Microbiol Infect 13:843–845 DOI

Schuster D, Josten M, Janssen K, Bodenstein I, Albert C, Schallenberg A, Gajdiss M, Sib E, Szekat C, Kehl K, Parčina M, Hischebeth GTR, Bierbaum G (2018) Detection of methicillin-resistant coagulase-negative staphylococci harboring the class A mec complex by MALDI-TOF mass spectrometry. Int J Med Microbiol 308:522–526 DOI

Shah HN, Rajakaruna L, Ball G, Misra R, Al-Shahib A, Fang M, Gharbia SE (2011) Tracing the transition of methicillin resistance in sub-populations of Staphylococcus aureus, using SELDI-TOF mass spectrometry and artificial neural network analysis. Syst Appl Microbiol 34:81–86 DOI

Shore AC, Deasy EC, Slickers P, Brennan G, O'Connell B, Monecke S, Ehricht R, Coleman DC (2011) Detection of staphylococcal cassette chromosome mec type XI carrying highly divergent mecA, mecI, mecR1, blaZ, and ccr genes in human clinical isolates of clonal complex 130 methicillin-resistant Staphylococcus aureus. Antimicrob Agents Chemother 55:3765–3773 DOI

Stevenson LG, Drake SK, Shea YR, Zelazny AM, Murray PR (2010) Evaluation of matrix-assisted laser desorption ionization - time of flight mass spectrometry for identification of clinically important yeast species. J Clin Microbiol 48:3482–3486 DOI

Sunagar R, Hegde NR, Archana GJ, Sinha AY, Nagamani K, Isloor S (2016) Prevalence and genotype distribution of methicillin-resistant Staphylococcus aureus (MRSA) in India. J Glob Antimicrob Resist 7:46–52 DOI

Walker J, Fox AJ, Edwards-Jones V, Gordon DB (2002) Intact cell mass spectrometry (ICMS) used to type methicillin-resistant Staphylococcus aureus: media effects and inter-laboratory reproducibility. J Microbiol Methods 48:117–126 DOI

Wang R, Braughton KR, Kretschmer D, Bach THL, Queck SY, Li M, Kennedy AD, Dorward DW, Klebanoff SJ, Peschel A, DeLeo FR, Otto M (2007) Identification of novel cytolytic peptides as key virulence determinants for community-associated MRSA. Nat Med 13:1510–1514 DOI

Watson PF, Petrie A (2010) Method agreement analysis: a review of correct methodology. Theriogenology 73:1167–1179 DOI

Wolters M, Rohde H, Maier T, Belmar-Campos C, Franke G, Scherpe S, Aepfelbacher M, Christner M (2011) MALDI-TOF MS fingerprinting allows for discrimination of major methicillin-resistant Staphylococcus aureus lineages. Int J Med Microbiol 301:64–68 DOI

Xie X, Bao Y, Ouyang N, Dai X, Pan K, Chen B, Deng Y, Wu X, Xu F, Li H, Huang S (2016) Molecular epidemiology and characteristic of virulence gene of community-acquired and hospital-acquired methicillin-resistant Staphylococcus aureus isolates in Sun Yat-sen Memorial hospital, Guangzhou, Southern China. BMC Infect Dis 16:339 DOI