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Updated: Jun 6, 2026
Development of a More Sensitive and Specific Chromogenic Agar Medium for the Detection of Vibrio parahaemolyticus and Other Vibrio Species
Published on: November 8, 2016
Evaluation of a chromogenic agar medium for the detection of extended-spectrum ß-lactamase-producing
1Department of Infection Control and Prevention, The University of Tokyo Hospital, Tokyo, Japan. saito-lab@umin.ac.jp
Aim:
To compare the performance of a new chromogenic agar medium CHROMagar ESBL (KC-ESBL) to chromID ESBL (SB-ESBL) for the detection and presumptive identification of extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae directly from clinical specimens.
Methods And Results:
A total of 256 specimens were screened for ESBL producers. Also, the genotypes of the ESBLs and plasmid-mediated AmpC ß-lactamases (pAmpCBLs) were characterized by PCR and sequencing. Among the 256 specimens, 17 (6.6%) ESBL producers were isolated on both media. The sensitivity, specificity, positive predictive value and negative predictive value were higher for KC-ESBL (100, 93.3, 51.5 and 100%, respectively) than for SB-ESBL (88.2, 92.9, 46.9 and 99.1%, respectively) (P = 0.72). Enterobacteriaceae harbouring pAmpCBL genes as well as chromosomal cephalosporinase- and penicillinase-hyperproducing Enterobacteriaceae and Pseudomonas aeruginosa accounted for the false-positive results.
Conclusion:
KC-ESBL can detect ESBL producers from clinical specimens with good selectivity and rapid presumptive identification by means of colony colour at 24 h.
Significance And Impact Of The Study:
This is the first study that has evaluated the performance of KC-ESBL that enables the detection and presumptive identification of ESBL producers from clinical specimens.
