[Trends and changes in antimicrobial resistance of clinical isolates from 11 hospitals in Beijing area].

OBJECTIVE

To study the antimicrobial resistance and its changes of clinical isolates in Beijing area.

METHODS

The diameters of the inhibition zones of clinical isolates around antibiotic susceptibility test discs at 12 hospitals in Beijing area were computerfiled and analysed by the software of 'WHONET' according to NCCLS published in 1994.

RESULTS

A total of 10,305 isolates were collected in 1995. The percentages of resistance were as follows: (1) in E. coli: amikacin, 8%, ceftazidime, 15%, the other third generation cephalosporins, about 30%, (2) in Klebsiella spp: ofloxacin, 0%, ceftazidime, 15%, ciprofloxacin, 17%, norfloxacin, 15%, ofloxacin, 5%, (4) in Staph. aureus: norvancomycin, 0%, (5) in Strep. pneumoniae: penicillin G, 9%, (6) in Enterococcus spp: norvancomycin, 7%. The antimicrobial resistant changes over a six year period from 1990 to 1995 were surveyed and it was found that resistant percentage of the most isolates to quinolones, for example norfloxacin, increased significantly year by year and no remarkable differences of resistance to antimicrobial agents but quinolones were observed in Ps. aeruginosa.

CONCLUSION

Antimicrobial resistance should be emphasised during clinical therapy with antimicrobial agents, and trends in antimicrobial resistance of isolates should be followed.