Direct and rapid detection of extended-spectrum β-lactamase by chromogenic Cica-β test using culture fluid of positive blood culture bottles

Abstract

The rapid detection of extended-spectrum β-lactamase (ESBL) is important for appropriate antimicrobial selection and healthcare-associated infection control, because bloodstream infections caused by gram-negative bacilli are associated with a high mortality rate. In this study, a rapid method of detecting ESBL by the chromogenic Cica-β test using the culture fluid of positive blood culture bottles (Cica-β direct method) was compared with a conventional confirmation test. The tests were compared using 68 isolates with positive blood culture at Sapporo Medical University Hospital. As a result, the finding of 17/51 isolates judged to be ESBL-producing bacteria/nonproducing bacteria by the Cica-β direct method was completely consistent with that by the conventional confirmation test. Results suggest that the Cica-β direct method is useful as a rapid and simple test.