Akademik Veri Yönetim Sistemi
Mikrobiyoloji Bulteni, cilt.56, sa.3, ss.404-415, 2022 (SCI-Expanded)
© 2022 Ankara Microbiology Society. All rights reserved.In recent years, with the increase of carbapenem resistance in Acinetobacter, Pseudomonas, Enterobacterales species, the use of colistin in treatment has gradually increased. Since the broth microdilution method which is recommended as a reference method in colistin susceptibility tests, is laborious and expensive and other susceptibility tests do not give reliable results, all these cause laboratories to search for new methods for the determination of colistin susceptibility testing. In this study, it was aimed to compare the broth microdilution method which is the reference method with the colistin broth disc elution and rapid resapolymyxin NP tests for the determination of the susceptibility of colistin in Acinetobacter, Pseudomonas, Enterobacterales species which are common healthcare-associated infection agents.Colistin susceptibility of a total of 157 isolates isolated from patients hospitalized in Ankara City Hospital [Klebsiella pneumoniae (n= 74), Acinetobacter spp. (n= 33), Escherichia coli (n= 26), Pseudomonas aeruginosa (n= 24)] were tested by broth microdilution, colistin broth disc elution and rapid resapolymixin NP methods. The categorical and basic agreement was evaluated by comparing the broth microdilution results with the rapid resapolymyxin NP results and the colistin broth disc elution. When compared with broth microdilution, the categorical agreement of colistin broth disc elution test for Enterobacterales, Acinetobacter, Pseudomonas species was found to be 93%, 48%, 100%, respectively. When the essential agreement was evaluated the values of 95%, 45%, 100% were found, respectively. Very major error rates were found to be 10%, 70% and 0%, respectively. The categorical agreement of the rapid resapolymyxin test for Enterobacterales, Acinetobacter, Pseudomonas species was 85%, 36%, 100%, while very major error rates were found to be 10%, 88% and 0%, respectively. When compared with the reference method, both tests showed high categorical and essential agreements for P.aeruginosa. Accepted level of categorical and essential agreement was found in colistin broth disc elution method for Enterobacterales species, and low categorical agreement was found in rapid resapolymyxin NP test. For Acinetobacter species, both tests detected low categorical agreement and high rate of very major error. In addition, compared to the broth microdilution method, both colistin broth disc elution and rapid resapolymyxin NP tests were found to be cost-effective and easy to prepare. It was considered to be an additional advantage to have the results in rapid polymyxin NP test in four hours. In conclusion, in our study, it was shown that both colistin broth disc elution and rapid resapolymyxin NP test methods can be used in determining the susceptibility of colistin for P.aeruginosa and Enterobacterales species but both methods were found to be unsuccessful for Acinetobacter species.