尿路感染症におけるMelysinの臨床効果とdisk成績の関連性について

Abstract

The clinical effect of Melysin(R) on acute simple E. coli cystitis was evaluated in fifteen patients and compared with the result of the disk test. All of the patients showed a highly satisfactory response. In two, the result of the disk test with the 10[9]/ml inoculation was non-sensitive to Melysin(R) while the others were sensitive. When the inoculum size was reduced to 10[6]/ml the non-sensitive pathogen showed sensitivity. For evaluating the influence of inoculum size on the disk test, one hundred strains of clinically isolated E. coli were studied. Ninety-three strains were sensitive and only 4 strains were non-sensitive to Melysin(R) with inoculation of 10[6]/ml. When the inoculum size was increased to 10g/ml, 63 strains remained sensitive and the rest became non-sensitive, that is, the disk test was greatly influenced by inoculum size in thirty-three of the 100 strains. It has already been reported that the MIC of mecillinam to E. coli is influenced by the inoculums size. In the same way, the disk test of Melysin(R) against E. coli was also influenced by the inoculums size. This suggests that the clinical sensitivity test for Melysin(R) must be performed under the condition that an inoculum size of pathogen is 10[6]/ml.