[Treatment of bacterial pneumonias with cefuroxime-axetil. Predictive value of measurement of the in vitro susceptibility].

Cefuroxime axetil is an oral cephalosporin with proven efficacy in adult lower respiratory tract infections. Indeed, it has a broad spectrum of activity in vitro, covering most pathogens isolated in this setting and showing good stability in the presence of betalactamases. In vitro susceptibility data are a major element in the choice of antimicrobial agent. The aim of this study was to determine the predictive value of the cefuroxime minimal inhibitory concentration (MIC) on the clinical outcome of infections treated with cefuroxime axetil. One hundred-and-seventeen (117) patients with radiologically confirmed community-acquired pneumonia of presumed bacterial origin were enrolled in a prospective multicenter trial of cefuroxime axetil therapy (500 mg twice daily). The pathogen was identified in 44 patients who were treated for a mean of 8.8 days. Most isolates were S. pneumoniae (65.9%) and H. influenzae (15.9%). The MIC was known for 35 isolates and was < or = 4 micrograms/ml in 30 cases (85.7%). The MIC value was a good predictor of clinical efficacy with a sensitivity of 100%, a specificity of 83% and a positive predictive value of 97%; the latter value indicates that therapeutic success is virtually certain when the bacterium causing pneumonia is susceptible to cefuroxime.