Susceptibility testing interpretive criteria and drug stability for cefdinir, cefetamet, and cefpodoxime against Neisseria gonorrhoeae

Abstract

Cefdinir, cefetamet, and cefpodoxime, three orally administered cephalosporins, were tested against 100 strains of Neisseria gonorrhoeae having various antimicrobial susceptibility patterns. Triplicate testing of each organism strain was performed for all agar dilution and disk diffusion tests. Cefdinir was the most active compound (MIC90) micrograms/ml) especially against gonococci with chromosomal-mediated resistance to penicillin. The recommended susceptible interpretive criteria were as follows: for the 5-micrograms cefdinir disk, > or = 31 mm (MIC correlate, < or = 0.25 microgram/ml); for the 10-micrograms cefetament disk, > or = 29 mm (MIC correlate, < or = 0.5 microgram/ml; for the 30-micrograms cefetamet disk, > or = 31 mm (MIC correlate, < or = 0.5 microgram/ml); and for the 10-micrograms cefpodoxime disk, > or = 29 mm (MIC correlate, < or = 0.5 microgram/ml). No organisms resistant to these new cephalosporins were detected. Cefdinir, cefetamet, and defpodoxime were stable in GC agar medium for at least 21 days when stored at 2 degrees-5 degrees C.