Antimicrobial resistance and genomic screening of clinical isolates of thermophilic Campylobacter spp. from south-east Queensland, Australia.
OBJECTIVE
To screen 90 clinical isolates of thermophilic Campylobacter species for putative resistance to ampicillin, erythromycin and tetracycline and perform numerical analysis to determine isolate relatedness.


RESULTS
Disc diffusion, E-test MIC and agar dilution methods were performed. Disc diffusion testing showed 87 (97%) isolates appeared resistant to ampicillin at 10 microg; 14 (16%) resistant to tetracycline at 30 microg; and three (3.4%) resistant to erythromycin at 15 microg. E-test MICs showed a range of 0.5 to >256 mg l(-1) for ampicillin; 16 to >256 mg l(-1) for tetracycline; and >256 mg l(-1) for erythromycin. E-test showed 68% correlation (+/-1 log2 dilution) with agar dilution for ampicillin, 100% for erythromycin and 64% for tetracycline. Disc diffusion testing showed 100% correlation with agar dilution for erythromycin and tetracycline, and 77% for ampicillin. Numerical analyses of restriction endonuclease (RE) fragment profiles suggested a high level of isolate variation.


CONCLUSIONS
The incidence of resistance of thermophilic Campylobacter spp. to erythromycin and tetracycline is low in south-east Queensland.


CONCLUSIONS
Disc diffusion susceptibility testing may be used to screen thermophilic Campylobacter spp. for putative resistance to erythromycin and tetracycline. Agar dilution should be used to determine ampicillin susceptibility.
Alfredson
D A
DA
School of Health Sciences, Griffith University, Gold Coast Campus, Southport, Queensland, Australia. david_alfredson@health.qld.gov.au
Akhurst
R J
RJ
Korolik
V
V
D000668:Ampicillin Resistance / Q000235:genetics; D002167:Campylobacter / Q000187:drug effects* / Q000235:genetics; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000032:analysis; D024881:Drug Resistance, Bacterial; D004917:Erythromycin / Q000494:pharmacology; D008826:Microbial Sensitivity Tests / Q000379:methods; D015183:Restriction Mapping / Q000379:methods; D013753:Tetracycline Resistance / Q000235:genetics
D004269:DNA, Bacterial; D004917:Erythromycin