Is it time to ditch trimethoprim as first-line UTI therapy?

Doctors say it is time to rethink the use of trimethoprim as empirical treatment for UTIs, with results from an Australian study showing high rates of resistance to the first-line antibiotic.
The UNSW Sydney–led researchers have found that trimethoprim resistance rates range from 20% to 30% of Escherichia coli samples taken from hospitals, aged care facilities and the community.
In contrast, they said resistance to second-line nitrofurantoin was deemed low, while resistance to third-line cefalexin was moderate.
“Although the current Australian Therapeutic Guidelines continue to recommend trimethoprim because of the low risk of adverse outcomes from treatment failure, our data suggest a necessary evaluation of trimethoprim as the first-line therapy for empirical treatment of cystitis,” they wrote.