Abstract: Objective To explore the relationship between various antimicrobial consumption and bacterial resistance. Methods The defined daily doses(DDDs) every 100 patient days of various antimicrobial drugs and the rate of drug resistance of staphylococcus aureus, enterococcus, escherichia coli, klebsiella pneumoniae, pseudomonas aeruginosa, acinetobacter baumannii were calculated every six months from 2006 to 2009,then the data were analyzed by the method of multiple linear regressio. Results The rate of resistance of Staphylococcus aureus to erythromycin was significantly negatively associated with the usage of first generation cephalosporins. The rate of resistance of staphylococcus aureus to clindamycin was significantly positively associated with the usage of tetracyclines. The rate of resistance of enterococcus to ampicillin was significantly negatively associated with the usage of broad-spectrum penicillin. A positive correlation was found between the consumption of carbapenems and the resistance of Escherichia coli to ceftazidime, the resistance to aztreonam positively associated with the usage of quinolones, the resistance to amikacin positively associated with the usage of broad-spectrum penicillin. A negative correlation was found between the consumption of fourth-generation cephalosporins and the resistance of klebsiella pneumoniae to amikacin, the resistance to ceftazidime and cefepime negatively associated with the usage of broad-spectrum penicillin. A negative correlation was found between the consumption of β-lactamase inhibitors and the resistance of pseudomonas aeruginosa to piperacillin-tazobactam ceftazidime, cefepime and amikacin. The rate of resistance of acinetobacter baumannii to imipenem had a positive correlation with the usage of carbapenems. Conclusion There exists correlation between antimicrobial consumption and rates of bacterial resistance.

Key words: drug resistance, antimicrobial, defined daily doses(DDDs), correlation