[Detection of extended-spectrum ß-lactamase-producing Enterobacteriaceae in rectal swabs with the Mastdiscs™ ID AmpC ßLSE detection set]. / Dépistage du portage digestif des entérobactéries productrices de ß-lactamase à spectre étendu par ensemencement direct des écouvillons rectaux à l'aide de la méthode Mastdiscs™ ID AmpC ßLSE.

OBJECTIVES: The double-disk synergy test was compared to the Mastdiscs™ ID AmpC and ESßL method for detection of ESßL production in rectal swab. METHODS: Two hundred and forty-nine rectal swabs were directly inoculated onto Mueller-Hinton plates and analyzed according to both methods. RESULTS: A total of 41 (16%) and 208 (84%) were positive and negative for ESßL, respectively. Twelve (29%) and 20 (49%) of the 41 rectal swabs positive for ESßL were detected after 24h of incubation with the double-disk synergy test and the Mastdiscs™ method, respectively (P=0.013). One hundred fifty-eight (76%) et 183 (88%) of the 208 rectal swabs were detected negative for ESßL after 24h of incubation with the double-disk synergy test and the Mastdiscs™ method, respectively (P<0.001). Finally, 79 (32%) and 46 (18%) rectal swabs respectively inoculated according to the double-disk synergy test and the Mastdiscs™ method were inconclusive after 24h of incubation. The better performance of the Mastdiscs™ method was due to an easier detection of cephalosporinase producing bacteria. CONCLUSIONS: The Mastdiscs™ method is a simple phenotypic method that detects more easily ESßL and non-ESßL producing bacteria in rectal swab.