In vitro interactions of combinations of colistin with meropenem, rifampicin and tigecycline in colistin-resistant, biofilm-forming Klebsiella pneumoniae

• Published in: Diagnostic microbiology and infectious disease Vol. 110; no. 2; p. 116408
• Main Authors: Müderris, Tuba, Dursun Manyaslı, Gülden, Kaya, Selçuk, Gül Yurtsever, Süreyya
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2024
• Subjects: Antibiofilm effects; Antimicrobial synergy; Biofilm; Biofilm inhibitory concentration; Klebsiella pneumoniae; Antimicrobial synergy; Intensive care units; Minimal inhibitory concentration; Antibiofilm effects; Fractional inhibitory concentration index; Biofilm inhibitory concentration; Biofilm; Klebsiella pneumoniae; Optical density
• ISSN: 0732-8893; 1879-0070; 1879-0070
• DOI: 10.1016/j.diagmicrobio.2024.116408

In this study, it was aimed to reveal the in vitro interactions of combinations of colistin with meropenem, rifampicin and tigecycline in colistin-resistant, biofilm-forming Klebsiella pneumonia. A total of 30 isolates, 15 of which formed biofilms and 15 did not form biofilms, were randomly selected from K. pneumoniae isolates growing in blood samples. The synergy rates of colistin-meropenem, colistin-tigecycline, colistin-rifampicin combinations in planktonic/sessile bacteria are; It was determined as 83,3%/73,3%, 66,6%/33,3%, 100%/60% respectively. Biofilm inhibitory concentration (BIC) of colistin, meropenem, tigecycline, and rifampicin significantly increased after biofilm formation. The synergistic activity seen in the sessile form was independent of the planktonic form. Although a high synergistic effect was observed in the meropenem-colistin combination on sessile bacteria, colistin had very high BIC ​​in all combinations. Large-scale studies are needed in which the number of isolates studied is large, bacterial resistance profiles are evaluated genomically, and various antimicrobial groups are included.