Study on bacterial infection by the investigation with antimicrobial susceptibility against various clinical isolates. I. The results of susceptibility and the amounts of drug used during seven years

Abstract

Drug susceptibility/resistance of 42, 940 strains was investigated, of clinical isolates including 28bacterial species isolated from 1979 to 1986 at Tokyo Metropolitan Komagome Hospital. Using a triplet-disk method, the following results were obtained.1) Less than 50% of isolates in Staphylococcus aureus, Proteus vulgaris, Proteus rettgeri, Pseudomonas aeruginosa, Pseudomonas putida, Xanthomonas maltopilia and Flavobacterium species appeared to be sensitive to the most frequently used drugs (major drugs) such as penems, cephems, chloramphenicol and tetracyclines.2) Bacterial species that turned to be resistant against the major drugs during this survey wereS. aureus, Enterococcus species, Salmonella species, Enterobacter species and P. aeruginosa.3) Total amounts of the major drugs used were nearly steady during the survey period. Among the orally administered drugs, cephems were the largest in quantity and followed by quinolone derivatives, penems, macrolides, tetracyclines. While the amount of use of parenterally administered drugs were in order of cephems, penems and aminoglycosides.4) Increasing number of drug resistant isolates against the particular drug (s) seems to be related to the amount of the drug (s) used, that might be due to acquired resistance factors. On the other hand, multi-drug-resistance of a part so called glucose non-fermentative gram-negative bacilli might be due to the other factor (s) such as low outer membrane diffusion etc.Thus, we would suggest that investigators should keep their attentions to the frequently isolated multi-drug-resistant pathogens such as S. aureus, Enterobacter species and P. aeruginos