Use of boronic acid disk methods to detect the combined expression of plasmid-mediated AmpC β-lactamases and extended-spectrum β-lactamases in clinical isolates of Klebsiella spp., Salmonella spp., and Proteus mirabilis

摘要: A study using boronic acid (BA), an AmpC enzyme inhibitor, was designed to detect the combined expression of plasmid-mediated beta-lactamases (pAmpCs) and extended-spectrum (ESBLs) in bacterial isolates naturally lacking chromosomal ampC genes. total 122 Klebsiella spp., Salmonella Proteus mirabilis producing or nonproducing pAmpCs and/or ESBLs were analyzed. Detection genes encoding AmpCs confirmed by polymerase chain reaction (PCR) followed sequencing PCR products. > = 5-mm increase zone diameter for i) cefoxitin (FOX) cefotetan (CTT) containing BA versus FOX CTT alone considered positive AmpC; ii) ceftazidime (CAZ)-clavulanate (CA) cefotaxime (CTX)-CA tested combination with CAZ CTX ESBL. The disk tests detected 98.4% organisms pAmpCs. All 21 pAmpC ESBL coproducers accurately CTX-CA CAZ-CA BA. In conclusion, test Clinical Laboratory Standards Institute methodology is simple very efficient method enzymes. particular, detects that harbor both ESBLs.