Marijan Tatjana, Plecko Vanda, Vranes Jasmina, Dzepina Ana Mlinarić, Bedenić Branka, Kalenić Smilja
Zavod za javno zdravstvo "Dr. Andrija Stampar", Zagreb, Hrvatska.
Med Glas (Zenica). 2010 Feb;7(1):46-53.
To determine the prevalence of ESBL-producing Escherichia coli and Klebsiella pneumoniae strains isolated from urine of nonhospitalized patients during a three-year period, to determine their antibiotic susceptibility, investigate the transfer of ESBL genes with cotransfer of resistance and to characterize isolated beta-lactamases.
Antimicrobial susceptibility was determined by disk diffusion and broth microdilution methods. The double-disk test was used for ESBL detection. Transfer of resistance was performed by broth mating method and characterization of isolated beta-lactamases by polymerase chain reaction.
The prevalence of ESBL-producing E. coli was 1.5% and of K. pneumoniae 4.1% with its different distribution according to patients' age and gender. ESBL-producing K. pneumoniae showed high resistance rates to aminoglycosides, cotrimoxazole, nitrofurantoin and quinolones while ESBL-producing E. coli isolates, with exception of high aminoglycoside resistance, showed low resistance rates to other antibiotics. Successful conjugation of ESBL genes was obtained with 25% E. coli and 76.2% K. pneumoniae strains. Comparing to E. coli, K. pneumoniae strains showed higher rates of aminoglycoside and cotrimoxazole resistance cotransfer. Beta-lactamases of investigated strains belonged to TEM, SHV and CTX-M families.
The existence of multiple-resistant ESBL-producing E. coli and K. pneumoniae strains was confirmed in observed outpatient population. ESBL-producing K. pneumoniae isolates, in contrast to ESBL-producing E. coli, showed higher resistance rates to non-beta-lactam antibiotics, probably caused by cotransfer of resistance genes located on the same plasmid as ESBL genes. It is important to monitor the prevalence of such strains and their possible spreading in the outpatient population of the Zagreb region.
确定在三年期间从非住院患者尿液中分离出的产超广谱β-内酰胺酶（ESBL）的大肠杆菌和肺炎克雷伯菌菌株的流行率，确定其抗生素敏感性，研究ESBL基因与耐药性共转移情况，并对分离出的β-内酰胺酶进行特性分析。
采用纸片扩散法和肉汤微量稀释法测定抗菌药物敏感性。采用双纸片试验检测ESBL。通过肉汤交配法进行耐药性转移，并通过聚合酶链反应对分离出的β-内酰胺酶进行特性分析。
产ESBL的大肠杆菌流行率为1.5%，肺炎克雷伯菌为4.1%，且根据患者年龄和性别分布不同。产ESBL的肺炎克雷伯菌对氨基糖苷类、复方新诺明、呋喃妥因和喹诺酮类药物显示出高耐药率，而产ESBL的大肠杆菌分离株，除对氨基糖苷类药物耐药率高外，对其他抗生素耐药率较低。25%的大肠杆菌菌株和76.2%的肺炎克雷伯菌菌株成功实现了ESBL基因的接合。与大肠杆菌相比，肺炎克雷伯菌菌株显示出更高的氨基糖苷类和复方新诺明耐药性共转移率。所研究菌株的β-内酰胺酶属于TEM、SHV和CTX-M家族。
在所观察的门诊人群中证实存在多重耐药的产ESBL大肠杆菌和肺炎克雷伯菌菌株。与产ESBL的大肠杆菌相比，产ESBL的肺炎克雷伯菌分离株对非β-内酰胺类抗生素显示出更高的耐药率，这可能是由于与ESBL基因位于同一质粒上的耐药基因共转移所致。监测此类菌株在萨格勒布地区门诊人群中的流行率及其可能的传播情况非常重要。
