Short sharp shock best for antibiotics
GPs should consider a 'short sharp shock' approach to antibiotic use as the most effective way of preventing resistant infections, researchers report.
Their study found antibiotic exposure was a 'strong risk factor' for resistant E. coli urinary tract infections – with use of trimethoprim raising risk by up to 14-fold. But use of short courses of high-dose antibiotics cut the likelihood of developing a resistant UTI.
The researchers, whose study was published online by the Journal of Antimicrobial Chemotherapy, took urine samples from 903 patients with UTI symptoms from 10 general practices in Wales. Those prescribed amoxicillin for seven days or more in the past month were at a four-fold raised risk of an ampicillin-resistant infection.
Trimethoprim-resistant infections were 8.5 times more likely in patients prescribed trimethoprim for seven or more days in the previous month. The risk rose to nearly 14-fold in those given scripts in the previous two to three months. But short courses of trimethoprim, of less than seven days, increased risk of resistance by only four times.
Study leader Dr Sharon Hillier, senior research fellow in epidemiology, statistics and public health at Cardiff University, said: 'Exposure to antibiotics is a strong risk factor for a resistant E. coli UTI. High-dose, shorter duration antibiotic regimens may reduce the pressure on the emergence of antibiotic resistance.'