A Selective Culture Medium for Screening Ceftazidime-Avibactam Resistance in Enterobacterales and Pseudomonas aeruginosa

摘要

The SuperCAZ/AVI medium was developed for screening ceftazidime-avibactam (CZA) resistance among Gram-negative bacteria (Enterobacterales and Pseudomonas aeruginosa). It was evaluated using 50 CZA-susceptible and 42 CZA-resistant Gram-negative isolates. Its sensitivity and specificity of detection were 100. Excellent performance of the medium was also observed by testing spiked stools, with the lower limit of detection ranging from 10(1) to 10(2) CFU/ml. This screening medium provides the opportunity to detect CZA-resistant isolates regardless of their resistance mechanisms.