[A consideration on the results of nationwide surveillance of antimicrobial susceptibilities--gram-negative bacilli].

The results of the semi-annual nationwide surveillance of antimicrobial susceptibilities, conducted by the Japanese Ministry of Health and Welfare during the period of January 1993 to July 1995, were analyzed for typical Gram-negative bacilli in the purpose of provision of an index for antimicrobial selection. During these 3 years, Escherichia coli, Citrobacter freundii, Enterobacter aerogenes and Proteus mirabilis showed slightly increasing tendency in susceptibility to fosfomycin (FOM) and Citrobacter freundii. Klebsiella pneumoniae and Enterobacter aerogenes showed slightly increasing tendency to minocycline (MINO). While Haemophilus influenzae and Haemophilus parainfluenzae showed slightly decreasing tendency to cefmetazole (CMZ). However, these annual changes were almost negligible. Generally, these microorganisms showed relatively good susceptibilities, every year, to the principal antimicrobial agents being approved for use against Gram-negative bacilli. However, Enterobacter cloacae, Enterobacter aerogenes, Serratia marcescens and Pseudomonas aeruginosa showed tendencies of decreased susceptibility to some of the antimicrobial agents. On the other hand, sulfamethoxazole-trimethoprim (ST), CMZ, latamoxef (LMOX), gentamicin (GM) and amikacin (AMK) showed good activities against some of the Gram-negative bacilli to which no indications are approved. In conclusion, bedside the identification of the causative microorganisms and the performance of antimicrobial susceptibility testing, such analyses (graphics of susceptibility tendency of clinical isolates to variety of antimicrobial agents) could be used as an index for selection of antimicrobial agents, when emergent and urgent selection of antimicrobial agents is necessary.