OBJECTIVE: To study the resistance mechanism of clinical isolates of Ureaplasma urealyticum resistant to fluoroquinolones. METHODS: Thirteen isolates of Ureaplasma urealyticum resistant to six fluoroquinolones were se...OBJECTIVE: To study the resistance mechanism of clinical isolates of Ureaplasma urealyticum resistant to fluoroquinolones. METHODS: Thirteen isolates of Ureaplasma urealyticum resistant to six fluoroquinolones were selected out of 184 clinical isolates and their QRDRs (quinolone resistance-determining region) gyrA, gyrB, parC and parE were amplified by PCR. Sequencing results were compared to those susceptible reference strains and a comparison of deduced amino acid sequences were performed. RESULTS: Sequence comparison revealed a C to A change at 87nt of gyrA QRDR leading to the substitution of Asp95 with glutamic acid and a C to T change at 50nt of parC QRDR leading to the substitution of Ser80 with leucine. CONCLUSION: These results suggest that a C to A change at 87nt of gyrA QRDR and a C to T change at 50nt of parC QRDR are associated with fluoroquinolone resistance of Ureaplasma urealyticum.展开更多
OBJECTIVE: To analyze the epidemiology of hospital and community-acquired infections caused by Klebsiella pneumoniae (K. pneumoniae) and risk factors for infections caused by resistant strains. METHODS: A retrospecti...OBJECTIVE: To analyze the epidemiology of hospital and community-acquired infections caused by Klebsiella pneumoniae (K. pneumoniae) and risk factors for infections caused by resistant strains. METHODS: A retrospective observational study was performed to analyze the relationship between antimicrobial use and bacterial resistance. RESULTS: A K. pneumoniae infection was diagnosed in 0.47% of patients (169 of 36 179) admitted to the hospital between 1 March 1999 and 31 August 2000. Of the 169 isolates, 166 (98.2%) were resistant to at least one antimicrobial and 91.1% (154/169) to two or more antibiotics. 98% were resistant to ampicillin, 77% to piperacillin, 64% to cephalothin, 60% to ampicillin/sulbactam, 59% to cefoperazone, 57% to cefazolin, 55% to cefuroxime, 51% to TMP-SMZ, 51% to tobramycin, 50% to gentamicin, 49% to aztreonam, cefetaxime and ceftriaxone respectively, 47% to ceftazidime, 47% to cefepime, 46% to ciprofloxacin, 46% to ticarcillin/clavulanate, 44% to amikacin, 38% to cefoxitin, 22% to piperacillin/tazobactam, while all strains were tested susceptible to imipenem. CONCLUSIONS: Prior receipt of amtimicrobial therapy was significantly associated with infection caused by a resistant organism and most strains were resistant to multiple antibiotics.展开更多
文摘OBJECTIVE: To study the resistance mechanism of clinical isolates of Ureaplasma urealyticum resistant to fluoroquinolones. METHODS: Thirteen isolates of Ureaplasma urealyticum resistant to six fluoroquinolones were selected out of 184 clinical isolates and their QRDRs (quinolone resistance-determining region) gyrA, gyrB, parC and parE were amplified by PCR. Sequencing results were compared to those susceptible reference strains and a comparison of deduced amino acid sequences were performed. RESULTS: Sequence comparison revealed a C to A change at 87nt of gyrA QRDR leading to the substitution of Asp95 with glutamic acid and a C to T change at 50nt of parC QRDR leading to the substitution of Ser80 with leucine. CONCLUSION: These results suggest that a C to A change at 87nt of gyrA QRDR and a C to T change at 50nt of parC QRDR are associated with fluoroquinolone resistance of Ureaplasma urealyticum.
基金ThisworkwassupportedbytheNaturalScienceFoundationofAnhuiEducationalBoard (No 2 0 0 1kj14 1)
文摘OBJECTIVE: To analyze the epidemiology of hospital and community-acquired infections caused by Klebsiella pneumoniae (K. pneumoniae) and risk factors for infections caused by resistant strains. METHODS: A retrospective observational study was performed to analyze the relationship between antimicrobial use and bacterial resistance. RESULTS: A K. pneumoniae infection was diagnosed in 0.47% of patients (169 of 36 179) admitted to the hospital between 1 March 1999 and 31 August 2000. Of the 169 isolates, 166 (98.2%) were resistant to at least one antimicrobial and 91.1% (154/169) to two or more antibiotics. 98% were resistant to ampicillin, 77% to piperacillin, 64% to cephalothin, 60% to ampicillin/sulbactam, 59% to cefoperazone, 57% to cefazolin, 55% to cefuroxime, 51% to TMP-SMZ, 51% to tobramycin, 50% to gentamicin, 49% to aztreonam, cefetaxime and ceftriaxone respectively, 47% to ceftazidime, 47% to cefepime, 46% to ciprofloxacin, 46% to ticarcillin/clavulanate, 44% to amikacin, 38% to cefoxitin, 22% to piperacillin/tazobactam, while all strains were tested susceptible to imipenem. CONCLUSIONS: Prior receipt of amtimicrobial therapy was significantly associated with infection caused by a resistant organism and most strains were resistant to multiple antibiotics.
