Extended-spectrum beta-lactamase producers: Detection for the diagnostic laboratory

Conclusions: Phenotypic screening disk diffusion test versus the confirmatory agar dilution MIC tests with cefotaxime and ceftazidime correlated well with the final ESBL status (kappa 0.852 and 0.905 P < 0.001) and (kappa 0.911 and 0.822 P < 0.001). The tests show 99-100% sensitivity, 75-83.3% specificity, and positive likelihood ratios between 4.0 -5.9. E-test confirmed 6 of 12 discordant results as ESBLs. Of the 96 nosocomial isolates screened as possible ESBL producers by the Kirby-Bauer disk diffusion test, 86.5% were confirmed ESBL producers. Genotyping on the ICU isolates by PFGE revealed a genetically diverse population suggesting no transmission of phenotypically similar ESBL strains within the ICUs.
Source: Journal of Global Infectious Diseases - Category: Infectious Diseases Authors: Source Type: research