Multiple heteroresistance to tigecycline and colistin in Acinetobacter baumannii isolates and its implications for combined antibiotic treatment.

ABSTRACT:

Background

We investigated the presence of heteroresistance against both tigecycline and colistin in Acinetobacter baumannii and then evaluated the effectiveness of combined antibiotic treatment given the existence of discrete tigecycline- and colistin-resistant subpopulations.

Methods

We performed population analysis profiling (PAP) to evaluate the degree of composite heteroresistance in A. baumannii isolates, with the extent of this resistance quantified using subsequent antibiotic susceptibility testing. We then evaluated the amino acid sequence of PmrBAC and the relative mRNA expression levels of pmrB. Finally, we investigated the combined antibiotic efficacy of tigecycline and colistin in multiple-heteroresistant isolates using dual PAP and in vitro time-killing assays.

SUBMITTER: Jo J 

PROVIDER: S-EPMC10245395 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature