Prediction of bacterial susceptibility to cefpodoxime by using the ceftriaxone minimum inhibitory concentration result.

The cross-resistance or cross-susceptibility of cefpodoxime and ceftriaxone for 3700 strains of Enterobacteriaceae, oxacillin-susceptible staphylococci, Streptococcus spp., Haemophilus influenzae, Moraxella catarrhalis, and Neisseria gonorrhoeae was evaluated. With the exception of tests with Enterobacter spp. and Morganella morganii, the ceftriaxone minimum inhibitory concentration (MIC) result interpretive criteria predicted bacterial susceptibility (or resistance) to cefpodoxime with an acceptable rate of serious interpretive errors (1.5%) and an absolute categorical agreement > 92%. By using cefpodoxime interpretive criteria for ceftriaxone MICs, the interpretive errors for testing enteric bacilli were reduced from 2.1% to 1.5%.