Evaluation of Colistin Susceptibility Results in Multidrug-Resistant Gram-Negative Bacilli by Colistin Broth Disk Elution Method Çok İlaca Dirençli Gram-Negatif Basillerde Kolistin Duyarlılık Sonuçlarının Kolistin Sıvı Disk Elüsyon Yöntemi ile Değerlendirilmesi

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Özkaçmaz A., Milletli-Sezgin F.

Klimik Dergisi, vol.35, no.3, pp.155-158, 2022 (ESCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 35 Issue: 3
  • Publication Date: 2022
  • Doi Number: 10.36519/kd.2022.4245
  • Journal Name: Klimik Dergisi
  • Journal Indexes: Emerging Sources Citation Index (ESCI), Scopus, Academic Search Premier, CAB Abstracts, CINAHL, EMBASE, Veterinary Science Database, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.155-158
  • Keywords: antibiotic resistance, broth microdilution, colistin, disc elution, Enterobacterales
  • Van Yüzüncü Yıl University Affiliated: Yes


© 2022, DOC Design and Informatics Co. Ltd.. All rights reserved.Objective: Determining colistin susceptibility according to the reference method is a significant problem for clinical microbiology laboratories. There is a need for a fast, easy-to-apply, and accurate method for laboratories with limit-ed opportunities. In our study, we aimed to evaluate the applicability of the colistin broth disk elution (CBDE) test. Methods: A total of 193 Gram-negative bacteria, which were isolated from various clinical specimens in our laborato-ry, were included in the study. Colistin susceptibility was determined by broth microdilution as the reference method. The CBDE test was performed as previously described. For each bacterial isolate, 0, ½, 1, 2, and 4 colistin discs (10 µg; BD) were added to 5 tubes containing cation-adjusted Mueller-Hinton broth (MHB). The final colistin concentrations in the tubes were 0 (growth control), 0.5, 1, 2, and 4 µg/ml, respectively. The minimum inhibitory concentration values were determined by visual evaluation 16-20 hours after the bacterial inoculation. Results: In the Enterobacterales group, the categorical agreement was 94%, the major error was 5%, and the very major error was 0%. In the non-fermentative bacteria group, the categorical agreement was found to be 94%, the major error 1%, and the very major error 33%, respectively. Conclusion: The CBDE test is a good alternative to broth microdilution in routine microbiology laboratories for the Enterobacterales group since it provides easy-to-apply, cost-effective testing for colistin susceptibility and has a high categorical agreement compared to the reference microdilution method.