Robicsek A, Sahm D F, Strahilevitz J, Jacoby G A, Hooper D C
Division of Infectious Diseases, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114-2696, USA.
Antimicrob Agents Chemother. 2005 Jul;49(7):3001-3. doi: 10.1128/AAC.49.7.3001-3003.2005.
The plasmid-encoded quinolone resistance gene qnrA confers low-level quinolone resistance, facilitating selection of higher-level resistance. Epidemiologic surveys for qnrA were extended to isolates of Enterobacter spp. and to quinolone-susceptible Enterobacteriaceae. Two (10%) of 20 ceftazidime-resistant quinolone-susceptible Klebsiella pneumoniae strains carried the gene, as did 12 (17%) of 71 ceftazidime-resistant Enterobacter strains from across the United States. One of these Enterobacter isolates was quinolone susceptible. Thus, qnrA is present in quinolone-resistant and quinolone-susceptible Enterobacter and Klebsiella strains in the United States.
质粒编码的喹诺酮耐药基因qnrA可导致低水平喹诺酮耐药,有利于更高水平耐药性的选择。对qnrA的流行病学调查已扩展到肠杆菌属分离株和喹诺酮敏感的肠杆菌科细菌。20株对头孢他啶耐药但对喹诺酮敏感的肺炎克雷伯菌菌株中有2株(10%)携带该基因,来自美国各地的71株对头孢他啶耐药的肠杆菌菌株中有12株(17%)携带该基因。这些肠杆菌分离株中有一株对喹诺酮敏感。因此,在美国,qnrA存在于对喹诺酮耐药和敏感的肠杆菌及克雷伯菌菌株中。