Abstract
Purpose: Antibiotic resistance is widespread throughout the world and represents a serious health concern globally. There is therefore an urgent need for the development of novel tools for rapidly distinguishing antibiotic resistant bacteria from susceptible strains. Previous work has demonstrated that differences in antimicrobial susceptibility can be reflected in differences in the profile of volatile organic compounds (VOCs) produced by dissimilar strains. The aim of this study was to investigate the effect of the presence of cephalosporin antibiotics on the VOC profile of extended spectrum beta-lactamase (ESBL) and non-ESBL producing strains of Escherichia coli
Material and methods: In the study, VOCs from strains of Escherichia coli positive and negative for the most commonly encountered ESBL, CTX-M in the presence of cephalosporin antibiotics were assessed using solid-phase microextraction (SMPE) coupled with a combined gas chromatography-mass spectrometry/metal oxide sensor (GC-MS/MOS) system.
Results: Our proof-of-concept study allowed for distinguishing CTX-M positive and negative bacteria in 2 h after the addition of antibiotics. One MOS signal (RT: 22.6) showed a statistically significant three-way interaction (p = 0.033) in addition to significant two-way interactions for culture and additive (p = 0.046) plus time and additive (p = 0.020). There were also significant effects observed for time (p = 0.009), culture (p = 0.030) and additive (p = 0.028). No such effects were observed in the MS data. Conclusions: The results of our study showed the potential of VOC analysis using SPME combined with a GC-MS/MOS system for the early detection of CTX-M-producing, antibiotic-resistant E. coli, responsible for UTIs. This proof of concept work involves bacterial cultures with the addition of antibiotics and future work would see the approach extended to urine samples of patients.
Material and methods: In the study, VOCs from strains of Escherichia coli positive and negative for the most commonly encountered ESBL, CTX-M in the presence of cephalosporin antibiotics were assessed using solid-phase microextraction (SMPE) coupled with a combined gas chromatography-mass spectrometry/metal oxide sensor (GC-MS/MOS) system.
Results: Our proof-of-concept study allowed for distinguishing CTX-M positive and negative bacteria in 2 h after the addition of antibiotics. One MOS signal (RT: 22.6) showed a statistically significant three-way interaction (p = 0.033) in addition to significant two-way interactions for culture and additive (p = 0.046) plus time and additive (p = 0.020). There were also significant effects observed for time (p = 0.009), culture (p = 0.030) and additive (p = 0.028). No such effects were observed in the MS data. Conclusions: The results of our study showed the potential of VOC analysis using SPME combined with a GC-MS/MOS system for the early detection of CTX-M-producing, antibiotic-resistant E. coli, responsible for UTIs. This proof of concept work involves bacterial cultures with the addition of antibiotics and future work would see the approach extended to urine samples of patients.
| Original language | English |
|---|---|
| Journal | Advances in Medical Sciences |
| Early online date | 22 Sep 2021 |
| Publication status | E-pub ahead of print - 22 Sep 2021 |
Keywords
- Volatile organic compounds
- gas chromatography-mass spectrometry
- metal-oxide sensor
- antibiotic resistance
- urinary tract infection