临床分离的革兰阴性细菌的耐药谱及耐药机制的研究

目的 了解前临床上分离G^－细菌的药敏状况和耐药机制及提供合理使用抗生素的依据。方法 主要使用MICROSCAN WALKAWAY／－40全自动微生物分析仪对1999年3月－2000年3月全院住院病人的尿、痰、腹水、脓液、创面、前列腺液、血液等培养呈阳性的标本进行细菌鉴定和药敏试验，结果共检出G^-菌1152株包括27个菌属80个菌种，觉细菌是大肠埃希菌（16.1％）、铜绿假单胞菌（6.5％）、肺炎克雷伯菌（5.3％）等。G^-杆菌（除不动杆菌外）对第三代头孢霉素敏感率已降到（3.0%-76.1%)、对亚胺培南（80.7%-92%)、头孢哌酮／舒巴坦（58.8％－100％）、阿米卡星（41.4%-93.2%)、环丙沙星（30.5％－67.3％）较敏感；对第三代头孢霉素产生超广谱β－内酰胺酶（ESBLs），肺炎克雷伯菌高达35.0%-36.9%，大肠5埃希菌达21.8％－23％。对常用β-内酰胺类抗生素产诱导酶（IB），铜绿假单胸菌高达51％－60.9％，弗劳地枸橼酸菌达4.5％－63.6％，阴沟肠杆菌达8.7%-35.3％。结论 目前G^－杆菌对β-内酰胺类抗生素药的主要机制是产生ESBLs和IB0G^-杆菌引起的感染首选亚胺培南单用或第三代浆孢霉素复合制剂（头孢哌酮／舒巴坦）联合阿米卡星或氟喹酮类，第三代头孢霉素除非药敏提示否则不宜选用。

THE STUDY ON DRUG SUSCEPTIBILITY AND RESISTANT MECHANISMS OF GRAM NEGATIVE CLINICAL ISOLATES

Objective In order to use antibiotics reansonably in cilnic,drug susceptibilitys of clinical isolates were analysed Methods The gram negative clinical isolates from specimens of urine,sputum,peritoneal fluid,wound,abscess/pus,prostatic fluid,blood etc of the whole hospital patients form March 1999 to March 2000 were identified and tested the drug resistance to antimicrobial agents by MICROSCAN WALKAWAY-40 Results 1152 gram negative clinical strains were identified to be of 80 species of 27 genuses The common pathogenic bacteria were E coli(16 1%),p aeruginosa(6 5%),K pneumoniae(5 3%) Susceprtivity rate of gram negative bacilli(besides acinetobacter)to the third generation cephalosporins had decreased to 3 0%~76 1%,but to imipenem was (80 7%~92%),cefoperazone/sulbactam(58 8%~100%),amikacin(41 4%~93 2%),ciprofloxacin(30 5%~67 3%) In productivity rate of extended spectrum beta-lactamases(ESBLs) by gram negative bacilli to the third generation cephalosporins,K pneumoniae was 35 0%~36 9%,E coli 21 8%~23% In productivity rate of inducible beta-lactamases(IB)by gram negative bacilli to common beta-lactam antibacterials,P aeruginosa was 51%~60 9%,C freundii 4 5%~63 6%,E cloacae8 7%~35 3% Conclusion The production of ESBLs and IB was the main mechanism of gram negative bacilli resistance to beta-lactam antibacterials Imipenem alone or cefoperazone/sulbactam with amikacin or fluoroquinolones should be regard as the first line antibiotics,and the third generation cephalosporins should not be applied unless susceptibility test was proved