The relation between sale of antimicrobial drugs and antibiotic resistance in uropathogens in general practice

Background - Overuse of antimicrobial drugs has resulted in an alarming increase in bacterial resistance in most countries. The relevance for general practice is unknown. Objective - To evaluate the impact of the sale of antimicrobial drugs on bacterial resistance as found in uropathogens from general practice. Setting - General practice in Belgium and Norway. Methods - Observational study. Results - The sale of antimicrobial drugs indicated for use in the treatment of urinary tract infection was four times higher in Belgium than in Norway (18.5 vs 4.4 DDD/1000 inhabitants/day). The antibiotic resistance reported by microbiological laboratories as valid for general practice was significant higher in Belgium than in Norway (ampicillins (44% vs 27%), co-trimoxazole (28% vs 17%), fluoroquinolones (12% vs 2%) and nitrofurantoin (16% vs 11%, p < 0.0001 for all). However, the antibiotic resistance found in urine samples from dysuric women in general practice was similar (trimethoprim 14% vs 12%, co-trimoxazole 14% vs 11%, nitrofurantoin 7% vs 3%), except in the case of ampicillins (30% vs 19%, p < 0.05). Conclusion - The impact of the antimicrobial sale on resistance in uropathogens seems less than expected at the general practice level, even though local microbiological reports mention fairly high antibiotic resistance data. Adapted methods for following-up bacterial resistance evolution in general practice are needed.