Intended use
This rapid method is based on the identification of the hydrolysis of the beta-lactam ring of a cephalosporin in the presence of an indicator.
Utilizing this principle ROSCO has developed two new Diatabs; Cefotaxime + Indicator (ESBL) and Cefotaxime + Tazobactam + Indicator (ESBL). The test is performed quickly and the reading of the results is ready within 15 minutes to one hour, from the time the reaction is started.
Thus, applying this kit, in the routine screening of ESBLs, saves time and effort in the laboratory. This test kit can be used to determine the presence of an ESBL in culture, positive blood culture and urine specimen.
Interpretation
A change of colour from red to yellow indicates a positive reaction. If the reaction is positive after 15 minutes or 30 min, the test is finished (it is not necessary to incubate further), because positive reactions may fade out.
In a few cases an orange yellowish colour or light yellow is obtained after incubation, this is a positive result if the Cefotaxime+Tazobactam+Indicator remains red.
If Cefotaxime+Indicator (ESBL) tube turns yellow and the Cefotaxime+Tazobactam+Indicator remains red the test is positive for ESBL.
If Cefotaxime + Indicator (ESBL) turns yellow and Cefotaxime+Tazobactam+Indicator also turns yellow, the test is negative for ESBL, but probably positive for a different beta-lactamase.
If both tubes maintain the red colour: the test is negative for ESBL.
If the Cefotaxime + indicator is red, but the Cefotaxime+tazobactam+Indicator turns yellow, the test is uninterpretable.
