Antimicrobial susceptibility testing by broth microdilution method: widely available modification

Clinical Microbiology and Antimicrobial Chemotherapy. 2018; 20(1):62-67

​ Tapalskiy D.V., Bilskiy I.A.
10.36488/cmac.2018.1.62-67
minimal inhibitory concentration disks with antibiotics antimicrobial resistance
Section
Personal Experience
Type
Journal article
Publication
Clinical Microbiology and Antimicrobial Chemotherapy. 2018; 20(1):62-67

Objective.

To assess the possibility of standard disk application as an antibiotic source for determination of the minimal inhibitory concentrations (MICs) by serial microdilution method.

Materials and Methods.

A simple method of working solutions preparation using standard paper discs as an antibiotics source available in most microbiological laboratories is proposed. A multiple determination of antibiotic MICs for E. coli ATCC 25922 and P. aeruginosa ATCC 27853 strains was conducted.

Results.

Of the 576 MIC values determined by the modified method, 78.5% of the results corresponded to the control strains reference values, and 20.8% of the results were categorized as acceptable values.

Conclusions.

Use of standard disks as an antibiotics source for the working solutions preparation greatly simplifies a testing by serial microdilution method and makes it available to most microbiological laboratories.

Dmitry V. Tapalskiy

Gomel State Medical University, Gomel, Belarus

Bilskiy I.A.

Gomel State Medical University, Gomel, Belarus

  • 1. ISO 20776-1:2006 «Clinical laboratory testing and in vitro diagnostic test systems – Susceptibility testing of infectious agents and evaluation of performance of antimicrobial susceptibility test devices». Part 1: Reference method for testing the in vitro activity of antimicrobial agents against rapidly growing aerobic bacteria involved in infectious diseases.
  • 2. National Standard GOST R ISO 20776-1-2010 Clinical laboratory testing and in vitro diagnostic test systems – Susceptibility testing of infectious agents and evaluation of performance of antimicrobial susceptibility test devices. Part 1. Reference method for testing the in vitro activity of antimicrobial agents against rapidly growing aerobic bacteria involved in infectious diseases. Russian.
  • 3. European Centre for Disease Prevention and Control. Antimicrobial resistance surveillance in Europe 2015. Annual Report of the European Antimicrobial Resistance Surveillance Network (EARS-Net). Stockholm: ECDC; 2017. Available at: ecdc.europa.eu/sites/portal/files/media/en/publications/Publications/antimicrobial-resistanceeurope-2015.pdf.
  • 4. Central Asian and Eastern European surveillance of antimicrobial resistance. Annual report 2016. Available at: www.euro.who.int/__data/assets/pdf_file/0009/323568/CAESAR-­Annualreport-2016.pdf?ua=1.
  • 5. Diene S.M., Rolain J.M. Carbapenemase genes and genetic platforms in Gram-negative bacilli: Enterobacteriaceae, Pseudomonas and Acinetobacter species. Clin Microbiol Infect. 2014;20(9):831-838.
  • 6. Falagas M.E., Kasiakou S.K., Kofteridis D.P., Roditakis G., Samonis G. Effectiveness and nephrotoxicity of intravenous colistin for treatment of patients with infections due to polymyxin-only-susceptible (POS) gramnegative bacteria. Eur J Clin Microbiol Infect Dis. 2006;25(9):596-599.
  • 7. EUCAST warnings concerning antimicrobial susceptibility testing products or procedures. Available at: http://www.eucast.org/ast_of_bacteria/warnings/.
  • 8. Vasoo S. Susceptibility testing for the polymyxins: two steps back, three steps forward? J Clin Microbiol. 2017;55(9):2573-2582.
  • 9. Chew K.L., La M.V., Lin R.T.P., Teo J.W.P. Colistin and polymyxin B susceptibility testing for carbapenem-resistant and mcr-positive Enterobacteriaceae: comparison of Sensititre, MicroScan, Vitek 2, and Etest with broth microdilution. J Clin Microbiol. 2017;55(9):26092616.
  • 10. European Committee on Antimicrobial Susceptibility testing (EUCAST). Breakpoint tables for interpretation of MICs and zone diameters. Ver. 8.0 2018. Available at: www.eucast.org/clinical_breakpoints/.
  • 11. Kuti J.L. Optimizing antimicrobial pharmacodynamics: a guide for your stewardship program. Revista Médica Clínica Las Condes. 2016;27(5):615-624.
  • 12. Daikos G.L., Markogiannakis A. Carbapenemase-producing K. pneumoniae: (when) might we still consider treating with carbapenems? Clin Microbiol Infect. 2011;17:1135-1141.
  • 13. Grupper M., Kuti J.L., Nicolau D.P. Continuous and prolonged intravenous β-lactam dosing: implications for the clinical laboratory. Clin Microbiol Rev. 2016;29(4):759-772.
  • 14. Drusano G.L., Louie A. Optimization of aminoglycoside therapy. Antimicrob Agents Chemother. 2011;55(6):2528-2531.
  • 15. Flowers D.J. Use of sensitivity discs as primary antibiotic standards in MIC determination. J Clin Pathol. 1978;31(9):855-858.
Views
0 Abstract
0 PDF
0 Crossref citations
Shared