A RAPID METHOD FOR MEASURING ANTIBIOTIC SENSITIVITY OF BACTERIA

Abstract

A rapid antibiotic sensitivity test is described in which the criterion of sensitivity was the inhibition of microcolony formation on the surface of agar plates containing antibiotic. Results of the tests were available 4 hours after inoculation of the plates. Comparison between 4-hour microcolony readings and confirmatory observations after 20 hours incubation showed a discrepancy rate of 2.72%. The results obtained by the microcolony method showed a good correlation with those given by the paper disc method. Correlation with the tube dilution method was not so good, but there may be valid reasons for this. The merits and demerits of the microcolony method are discussed.