EVALUATION OF A RAPID AND NEW ANTIBIOTIC SUSCEPTIBILITY TESTING METHOD FOR ENTEROBACTERIACEAE FROM URINARY-TRACT INFECTIONS

URIFAST(R)Es et Es Plus (International Microbio, Signes, France) are r apid antimicrobial susceptibility testing method in broth medium witho ut using an automatic reader. A screening assay (URIFAST(R) Quatro 1C ou URIFAST(R) Twin 1C) is performed with a 4 or 9 antimicrobial agents with a concentration c' below the low critical concentration (c) defi ned by the Comite de l'Antibiogramme de la Societe Francaise de Microb iologie (CA-SFM). When a bacterial strain is presumed resistant, an an timicrobial susceptibility test with the two critical concentrations ( CA-SFM) can be performed with 5 or 10 antimicrobial agents antibiotiqu es (URIFAST(R) Twin ABG ou URIFAST(R) ABG(R)). 140 strains of Enteroba cteriaceae from urinary tract infections; E. coli (n = 94), P. mirabil is (n = 13), K. pneumoniae (n = 4), K. oxytoca (n = 6), C. diversus (n = 3), P. vulgaris (n = 1), M. morganii (n = 3), C. freundii (n = 4), E. aerogenes (n = 2), E. cloacae (n = 5) and S. marcescens (n = 5); we re isolated with CPS ID2(R) (bioMerieux, Marcy l'Etoile, France). URIF AST results were compared to Rapid ATB(R) Ur et ATE Ur results obtaine d after reading with ATE expression (bioMerieux). For each discrepancy , the minimal inhibitory concentration !MIG) by agar dilution was used as the reference method. Agreement obtained were 98,57% with Quatro 1 C, 98,40% with Twin 1C, 98, 14% with Twin ABG(R) and 98,39% with ABG(R ). 94% of beta-lactams susceptible Enterobacteriaceae were detected by the screening tray with the antimicrobial agent concentration c'. URI FAST Es et Es Plus are standardized and easy-to-use methods. Because o f their good performances, the URIFAST methods can be used to test ant imicrobial susceptibility for Enterobacteriaceae from urinary tract in fections.