Correlation of cefpodoxime susceptibility with cephalothin and cefuroxime for urinary tract isolates

Eisenhower Army Medical Center.
Journal of Medical Microbiology (Impact Factor: 2.25). 11/2013; 63(Pt_2). DOI: 10.1099/jmm.0.063040-0
Source: PubMed


This study attempted to determine whether cefuroxime was superior to cephalothin as a surrogate marker for cefpodoxime among urinary tract isolates. The Microscan© system was used to determine susceptibility for cephalothin and cefuroxime on consecutive cultures with a colony count of > 50,000 organisms. Simultaneously, an E-test for cefpodoxime was conducted. The cefpodoxime interpretation was compared to that of the other 2 agents, and the categorical agreement was calculated, defined as the percentage of identical susceptibility interpretations. Cefuroxime (83%) had a significantly higher categorical agreement than cephalothin (63%) among 300 isolates (p < 0.01). The major error rate was 16% for cephalothin, and 3% for cefuroxime. The very major error rate was 7% for cephalothin and 14% for cefuroxime among the 14 cefpodoxime-resistant isolates. For E.coli. the major error rates were 15% and 1% for cephalothin and cefuroxime, respectively. Very major error rates were 9% for both agents. Cefuroxime was a better predictor of cefpodoxime susceptibility than cephalothin, and appears to be the preferred surrogate agent for the Microscan© system, particularly for E. coli.

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