1887

Abstract

Vancomycin has become the first-line therapy for most infections caused by methicillin-resistant staphylococci.

To evaluate the vancomycin MIC, staphylococcal cassette chromosome (SCC) types and clonality of coagulase-negative staphylococci (CoNS) isolates recovered from neonates with true primary bloodstream infections (BSI).

CoNS isolates were prospectively recovered from blood cultures of non-repetitive patients admitted to a neonatal intensive care unit (NICU) in a tertiary-care hospital during a 3-year period. BSI was defined based on established criteria. Micro-organisms were identified phenotypically and by PCR. MIC-values for vancomycin and oxacillin were determined by broth dilution method and E-test. The SCC type conferring methicillin resistance was determined by multiplex PCR. The heterogeneous vancomycin (hV) resistance phenotype was screened on brain heart infusion agar containing 4 µg ml of vancomycin. The clonality was investigated by PFGE.

Seventy-four CoNS isolates were recovered from blood cultures of neonates during the study period but only 40 (54 %) were associated with true primary BSI. Nine (22.5%) babies died. was the most prevalent species (95 %; 38/40). All isolates were methicillin-resistant (MR). SCC type IV was predominant (55.3 %; 21/38). Most (80.0 %; 32/38) isolates exhibited vancomycin MIC-values of 2–4 µg ml not associated with the SCC type or clonality. Sixteen (42.1%) isolates displayed hV resistance. All babies who died were harbouring MR- exhibiting vancomycin MICs of 2–4 µg ml.

The findings of this study demonstrated that blood invasive MR- isolates recovered at NICU tend to show decreased vancomycin susceptibility making therapy of those fragile patients difficult.

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2020-01-01
2024-05-13
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References

  1. Becker K, Heilmann C, Peters G. Coagulase-negative staphylococci. Clin Microbiol Rev 2014; 27:870–926 [View Article]
    [Google Scholar]
  2. International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements (IWG-SCC) Classification of staphylococcal cassette chromosome mec (SCCmec): guidelines for reporting novel SCCmec elements. Antimicrob Agents Chemother 2009; 53:4961–4967 [View Article]
    [Google Scholar]
  3. Zong Z, Peng C, X. Diversity of SCCmec elements in methicillin-resistant coagulase-negative staphylococci clinical isolates. PLoS One 2011; 6:e20191 [View Article]
    [Google Scholar]
  4. Shore AC, Coleman DC. Staphylococcal cassette chromosome mec: recent advances and new insights. Int J Med Microbiol 2013; 303:350–359 [View Article]
    [Google Scholar]
  5. John JF, Harvin AM. History and evolution of antibiotic resistance in coagulase-negative staphylococci: susceptibility profiles of new anti-staphylococcal agents. Ther Clin Risk Manag 2007; 3:1143–1152
    [Google Scholar]
  6. Horan TC, Andrus M, Dudeck MA. CDC/NHSN surveillance definition of health care-associated infection and criteria for specific types of infections in the acute care setting. Am J Infect Control 2008; 36:309–332 [View Article]
    [Google Scholar]
  7. Iorio NLP, Ferreira RBR, Schuenck RP, Malvar KL, Brilhante AP et al. Simplified and reliable scheme for species-level identification of Staphylococcus clinical isolates. J Clin Microbiol 2007; 45:2564–2569 [View Article]
    [Google Scholar]
  8. Pereira EM, Schuenck RP, Malvar KL, Iorio NLP, Matos PDM et al. Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus haemolyticus: methicillin-resistant isolates are detected directly in blood cultures by multiplex PCR. Microbiol Res 2010; 165:243–249 [View Article]
    [Google Scholar]
  9. Clinical and Laboratory Standards Institute Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically; Approved Standard, 10th ed. Wayne, PA, USA: CLSI document M07–A10; 2015
    [Google Scholar]
  10. Clinical and Laboratory Standards Institute Performance Standards for Antimicrobial Susceptibility Testing; 25th Informational Supplement.M100-S25 Wayne, PA, USA: CLSI; 2015
    [Google Scholar]
  11. Nunes APF, Teixeira LM, Iorio NLP, Bastos CCR, de Sousa Fonseca L et al. Heterogeneous resistance to vancomycin in Staphylococcus epidermidis, Staphylococcus haemolyticus and Staphylococcus warneri clinical strains: characterisation of glycopeptide susceptibility profiles and cell wall thickening. Int J Antimicrob Agents 2006; 27:307–315 [View Article]
    [Google Scholar]
  12. Boye K, Bartels MD, Andersen IS, Møller JA, Westh H. A new multiplex PCR for easy screening of methicillin-resistant Staphylococcus aureus SCCmec types I-V. Clin Microbiol Infect 2007; 13:725–727 [View Article]
    [Google Scholar]
  13. Salgueiro VC, Iorio NLP, Ferreira MC, Chamon RC, Dos Santos KRN. Methicillin resistance and virulence genes in invasive and nasal Staphylococcus epidermidis isolates from neonates. BMC Microbiol 2017; 17:15–24 [View Article]
    [Google Scholar]
  14. Pereira CAP, Marra AR, Camargo LFA, Pignatari ACC, Sukiennik T et al. Nosocomial bloodstream infections in Brazilian pediatric patients: microbiology, epidemiology, and clinical features. PLoS One 2013; 8:e68144 [View Article]
    [Google Scholar]
  15. Jean-Baptiste N, Benjamin DK, Cohen-Wolkowiez M, Fowler VG, Laughon M et al. Coagulase-negative staphylococcal infections in the neonatal intensive care unit. Infect Control Hosp Epidemiol 2011; 32:679–686 [View Article]
    [Google Scholar]
  16. Miragaia M, Couto I, de Lencastre H. Genetic diversity among methicillin-resistant Staphylococcus epidermidis (MRSE). Microb Drug Resist 2005; 11:83–93 [View Article]
    [Google Scholar]
  17. Klingenberg C, Rønnestad A, Anderson AS, Abrahamsen TG, Zorman J et al. Persistent strains of coagulase-negative staphylococci in a neonatal intensive care unit: virulence factors and invasiveness. Clin Microbiol Infect 2007; 13:1100–1111 [View Article]
    [Google Scholar]
  18. Howden BP, Davies JK, Johnson PDR, Stinear TP, Grayson ML. Reduced vancomycin susceptibility in Staphylococcus aureus, including vancomycin-intermediate and heterogeneous vancomycin-intermediate strains: resistance mechanisms, laboratory detection, and clinical implications. Clin Microbiol Rev 2010; 23:99–139 [View Article]
    [Google Scholar]
  19. Chong J, Caya C, Lévesque S, Quach C. Heteroresistant vancomycin intermediate coagulase negative Staphylococcus in the NICU: a systematic review. PLoS One 2016; 11:e0164132 [View Article]
    [Google Scholar]
  20. Sinkeler FS, de Haan TR, Hodiamont CJ, Bijleveld YA, Pajkrt D et al. Inadequate vancomycin therapy in term and preterm neonates: a retrospective analysis of Trough serum concentrations in relation to minimal inhibitory concentrations. BMC Pediatr 2014; 14:193–198 [View Article]
    [Google Scholar]
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