1997 Volume 50 Issue 2 Pages 187-194
Between January, 1982 and December, 1994, 236 Pseudomonas aeruginosa strains were isolated from clinical specimens at our division, and were tested for serotypes and drug-susceptibilities to 15 antibiotics. Serotype G strains were isolated at the highest frequency (32.6%), and followed by strains of serotype B (15.7%), A (11.9%), E (9.3%), I (7.2%), F and M (5.5%), non-typable (5.1%), D (3.4%), H (2.1%), C and K (0.8%).
We examined the changes of isolation frequencies of different serotypes annually. Isolation frequencies of serotypes E and F showed tendency to decrease, whereas serotype I has been isolated increasingly year by year.
MIC90's of the 15 antibiotics were as follows, tosufloxacin: 0.78μg/ml, biapenem (BIPM) and ofloxacin (OFLX): 3.13 μg/ml, imipenem (IPM), ceftazidime, cefozopran, cefsulodin and gentamicin: 6.25 μg/ml, aztreonam and amikacin: 12.5μg/ml, piperacillin, cefoperazone and minocycline (MINO): 25μg/ml, fosfomycin: 100μg/ml and chloramphenicol:>200,μg/ml.
MIC90's of IPM, BIPM, MINO and OFLX increased 4-fold from stage I (1982-1987) through stage III (1992-1994) and the isolation frequency of drug-resistant strains increased year by year. In other words, antibiotic resistant strains appeared increasing with time.
No relationship between serotypes and drug-resistance were observ ed.
