EVALUATION OF E-TEST FOR TESTING ANTIMICROBIAL SUSCEPTIBILITIES OF NEISSERIA-GONORRHOEAE ISOLATES WITH DIFFERENT GROWTH MEDIA

The MICs for 101 isolates of Neisseria gonorrhoeae obtained by Etest ( AB-Biodisk, Solna, Sweden) and the agar dilution method on GC medium b ase supplemented with 1% Kellogg's defined supplement (GCMB) were comp ared. The overall percent agreement (within 1 log, dilution) between m ethods was greater than 97.9. The Pearson's correlation coefficients f or penicillin, tetracycline, erythromycin, and ceftriaxone for the two methods were 0.98, 0.97, 0.93, and 0.93 (P = 0.001), respectively, fo r comparisons on GCMB. The overall percent agreement was lower when he moglobin-supplemented GCMB was used. Etest is an attractive alternativ e to the agar dilution method for gonococcal antimicrobial susceptibil ity testing and should be further analyzed in multicenter studies.