"Emerging resistance in common pathogens is a world-wide phenomenon, and this is a significant issue for healthcare practitioners and their patients," said the lead author of the report, Professor John Turnidge, Affiliate Professor of Molecular and Biomedical Science at the University of Adelaide.
"Worrying" stats
"Compared with many other countries in our region, antibiotic resistance rates in Australia are still relatively low. However, there are some worrying trends in the latest data which, for example, show a doubling of resistance among E. coli against some important reserve antibiotics," he said.
"Importantly, this study looked at samples from patients who were not hospitalised, so these are rates of antibiotic resistance out there in the general Australian population."
Samples were collected at 29 health centres around Australia in 2012, from non-hospitalised patients with urinary infections. The study tested 2025 species of Escherichia coli (E. coli), 538 of Klebsiella and 239 of Enterobacter, and the results compared with the previous community study in 2008.
Overall, antibiotic multi-resistance (resistant to three classes of antibiotics) was found in 7.6 per cent of E. coli samples compared with 4.5 per cent four years earlier, 5.1 per cent of Klebsiella (compared with 4.4 per cent) and 5.4 per cent of Enterobacter (4.2 per cent in 2008).
While common strains of E. coli can cause urinary tract and other localised infections, some strains of E. coli can invade the blood stream and cause septicaemia (blood poisoning), which can result in up to 20 per cent mortality.
Resistance rising steadily
"E. coli is the species of most concern to us because it's showing a noticeable increase in resistance to one of the most commonly used antibiotics – its resistance to amoxycillin is now at 44 per cent," Professor Turnidge said.
"E. coli's resistance is also increasing to one of our last-line oral antibiotics, ciprofloxacin, which has risen from 4.2 per cent to 6.9 per cent between 2008 and 2012.
"This is despite the antibiotic being restricted to needy cases in the community.
"We're now seeing some E. coli resistance to reserve intravenous antibiotics, which practitioners would normally only use once the patient is sick enough to admit to hospital, with blood poisoning for example."
The results of the study, conducted for the Australian Group on Antimicrobial Resistance, are published on the website of the Department of Health, which funded the research.
