Monitoring antibiotic resistance in urinary isolates from the community--a spotter practice model

Awareness of the rise in antimicrobial resistance has led to recommendations for better prescribing guidelines, based on accurate laboratory sensitivity data. However, concerns have been raised of possible biases in sampling leading to skewed resistance rates results, and so a range of different enhanced surveillance models have been proposed. This study compared the differences between routine results from unselected primary care urine samples with results from samples from spotter practices. Five hundred and eighty-eight out of 2,288 urine samples received from three spotter practices were culture positive. Of the 510 isolates tested against a panel of commonly prescribed antibiotics, levels of resistance to ampicillin were 32.5%, and to trimethoprim 18.0% (p < 0.05). By comparison, of 40,026 urine specimens submitted by other practices, 9,382 were culture positive and the percentage antibiotic resistant was higher--36.3% to ampicillin and 22.6% to trimethoprim. Routinely submitted laboratory samples may overestimate the true levels of antibiotic resistance in the community. A spotter practice-model is an effective and viable way of collecting unbiased data.