Kanazawa Y, Kuramata T, Matsumoto K
Jpn J Antibiot. 1983 Apr;36(4):709-16.
Susceptibilities of 227 strains of 34 bacterial species to cefatrizine (CFT) were determined by the 2-fold agar dilution method in parallel with the diameter of inhibition zones by the single-disc method, under the experimental condition established by Kanazawa. The experiments demonstrated significant correlation between MIC by the dilution method and diameter of inhibition zone in each of conventional assay of the over-night (about 16 hours) incubation, delayed assay (about 24 hours incubation), and rapid assay (after 3-4 or 5-6 hours incubation), thus confirming applicability of the single-disc assay for CFT. Analysis of the data obtained by using CFT disc containing 30 micrograms revealed the primary regression equation to be: D (diameter, mm) = 25.6--9.6 log MIC (micrograms/ml) in conventional assay, D = 33.2--13.2 log MIC (micrograms/ml) in delayed assay, D = 15.8--4.7 log MIC (micrograms/ml) in 3-4 hours rapid assay and D = 20.2--7.0 log MIC (micrograms/ml) in 5-6 hours rapid assay, respectively. The range of variations in MICs estimated from the diameter of inhibition zone by the disc test was then calculated in comparison with that in MIC determined by the 2-fold agar dilution assays, as reference for the experimental errors which may be involved in the estimation of MIC of CFT by the single-disc assay.
在金泽建立的实验条件下，采用2倍琼脂稀释法测定了34种227株细菌对头孢三嗪（CFT）的敏感性，并与单纸片法测定的抑菌圈直径进行了平行比较。实验表明，在常规过夜（约16小时）培养测定、延迟测定（约24小时培养）和快速测定（3 - 4或5 - 6小时培养后）中，稀释法测定的最低抑菌浓度（MIC）与抑菌圈直径之间均存在显著相关性，从而证实了单纸片法对CFT的适用性。对含30微克CFT纸片所得数据的分析显示，常规测定中的主要回归方程为：D（直径，mm）= 25.6 - 9.6 log MIC（微克/毫升），延迟测定中为D = 33.2 - 13.2 log MIC（微克/毫升），3 - 4小时快速测定中为D = 15.8 - 4.7 log MIC（微克/毫升），5 - 6小时快速测定中为D = 20.2 - 7.0 log MIC（微克/毫升）。然后，将通过纸片试验抑菌圈直径估算的MIC变化范围与通过2倍琼脂稀释法测定的MIC变化范围进行比较，作为单纸片法估算CFT MIC时可能涉及的实验误差参考。
