Purpose: To evaluate the performance of the Uro4 HB&L™ system in screening ESBL/AmpC-producing Enterobacteriaceae as compared with the resistant test by VITEK 2. The resistance profile of the ESBL-producing bacteria was also evaluated.
Methodology: Blood culture samples were collected at bedside, inoculated directly into BD BACTEC™ culture bottles, and incubated. When microbial growth was found, samples were prepared for identification using MALDI-ToF. The Uro4 HB&L™ system was used for direct detection of ESBL/AmpC-producing bacteria compared with conventional methods.
Results: A total of 103 positive blood cultures containing Gram-negative bacteria were tested. Uro4™ HB&L screening results were obtained in up to 6.5 h, with 91.3% concordance with the VITEK2 system, with 85% sensitivity, 95.2% specificity, and 91.1% positive and 90.9% negative predictive values. The resistance profile of ESBL-producing bacteria tested in the present study showed increased resistance ratio to ciprofloxacin, gentamicin, and trimethoprim/sulfamethoxazole. In parallel, susceptibility to amikacin and meropenem was not affected.
Conclusions: The performance of the Uro4 HB&L™ system is acceptable for rapid screening ESBL/AmpC-producing Enterobacteriaceae. The data related to detecting ESBL-producing bacteria are crucial for managing antimicrobial therapy.
Keywords: Blood culture; Enterobacteriacea; Extended-spectrum beta-lactamase (ESBL); Uro4 HB&L™ system.