LAUSR

Graphical abstract Figure. No Caption available. HighlightsAntibiotic susceptibility of bacterial cultures were rapidly analysed by TD‐GC–MS.Cultures were analysed in under 30 min vs. 24 h for traditional tests.Differences in volatile profiles found between resistant and sensitive bacteria.Differences in volatile profiles found between three UTI‐causing bacterial species. Abstract Antibiotic resistance is set to be an unprecedented threat to modern medicine. ‘Sniffing’ bacteria potentially offers a rapid way to determine susceptibility. A successful proof‐of‐principle study is described, using thermal desorption‐gas chromatography‐mass spectrometry (TD‐GC‐MS) to ‘smell’ cephalexin and ciprofloxacin resistant and sensitive Urinary Tract Infection (UTI)‐causing bacteria. 578 peaks at unique retention times were detected from 86 chromatograms of 18 bacterial isolates (E. coli, K. pneumoniae and P. aeruginosa). The isolates were grown with and without the presence of antibiotic. Chi‐square analysis found 9 compounds that differed significantly between cephalexin sensitive and resistant isolates, and 22 compounds that differed significantly between ciprofloxacin sensitive and resistant isolates, at p ≤ 0.05. When antibiotic was added to the media, more differences were found in the cephalexin group, attributed to lysis, but not in the ciprofloxacin group. Further work with large sample sizes will potentially enable the development of diagnostic algorithms using presence/absence of particular compounds of interest.