铜绿假单胞菌耐药性及其产超广谱β-内酰胺酶实验研究

发布时间：2018-01-04 15:23

本文关键词：铜绿假单胞菌耐药性及其产超广谱β-内酰胺酶实验研究　出处：《安徽理工大学》2007年硕士论文　论文类型：学位论文

【摘要】： 目的调查医院内感染铜绿假单胞菌的耐药现状,并确定耐药菌株产超广谱β-内酰胺酶种类。方法采集临床标本,常规分离培养,采用Phoenix-100系统进行菌种鉴定,根据NCCIS标准通过纸片琼脂扩散法进行药敏试验;疑似产超广谱β-内酰胺酶细菌采用纸片扩散法ESBLs检测试验初步确证铜绿假单胞菌产超广谱β-内酰胺酶,提取细菌质粒DNA和染色体DNA,PCR试验检测ESBLs基因种类。结果临床标本分离到64株铜绿假单胞菌,64株铜绿假单胞菌对临床常用抗生素药敏试验结果显示对青霉素类、第一、二代头孢菌素类抗生素、头霉素类抗生素头孢西丁及复方磺胺的耐药率均较高,达90%以上,对第三代头孢菌素耐药率在20%—50%之间;对碳青酶烯类抗生素亚胺培南耐药率为15.6%;对酶抑制剂复合制剂替卡西林/克拉维酸耐药率为20.3%;对氨基糖苷类抗生素阿米卡星及喹诺酮类抗生素环丙沙星的耐药率分别为32.8%和29.7%。纸片扩散法ESBLs检测试验确证有27株铜绿假单胞菌产超广谱β-内酰胺酶,比较产ESBLs和非产ESBLs菌株耐药性,产ESBLs菌株对哌拉西林、头孢哌酮、头孢曲松、头孢他啶及氨曲南的耐药率明显高于非产ESBLs菌株(P＜0.05)。PCR试验检测ESBLs基因类型,20株铜绿假单胞菌质粒DNA和染色体DNA中均有TEM型基因;有4株铜绿假单胞菌质粒DNA中检测到OXA-10型基因,有2株细菌染色体DNA存在OXA-10型基因;其中有1株细菌的质粒DNA中同时检测到了TEM型基因和OXA-10型基因。结论本院医院内感染铜绿假单胞菌对临床常用抗生素耐药性和全国其他地区有差别:本院医院内感染铜绿假单胞菌产ESBLs率较高,检测了TEM型酶和OXA-10型酶,以TEM型酶较多;铜绿假单胞菌编码ESBLs基因多位于质粒DNA上,同时也存在于染色体DNA上;铜绿假单胞菌耐药性复杂多样,对第三代头孢菌素抗生素耐药机制主要以产ESBLs为主。图[11]表[7]参[54]
[Abstract]:Objective to investigate the drug resistance of Pseudomonas aeruginosa in hospital and to identify the extended-spectrum 尾 -lactamases. Methods Clinical specimens were collected, isolated and cultured routinely, strain identification was carried out by Phoenix-100 system, and drug sensitivity test was carried out by paper Agar diffusion method according to NCCIS standard. Extended-spectrum 尾 -lactamase producing bacteria were identified by disk diffusion ESBLs assay. Extended-spectrum 尾 -lactamases were obtained from Pseudomonas aeruginosa to extract bacterial plasmid DNA and chromosome DNA. The type of ESBLs gene was detected by PCR test. Results Sixty-four strains of Pseudomonas aeruginosa were isolated from clinical specimens. The results of antibiotic sensitivity test showed that they were resistant to penicillin, first and second generation cephalosporins. The resistance rates of cephalomycin antibiotics cefoxitin and compound sulfanilamide were higher than 90%, and the resistance rate to the third generation cephalosporins ranged from 20% to 50%. The resistance rate to imipenem was 15.6; The resistance rate of ticacillin / clavulanic acid to the compound preparation of enzyme inhibitor was 20.3; The resistance rates of ciprofloxacin and ciprofloxacin to aminoglycoside antibiotics were 32.8% and 29.77.There were 27 strains of Pseudomonas aeruginosa confirmed by disk diffusion ESBLs assay. Extended-spectrum 尾 -lactamases were produced. The drug resistance of ESBLs producing and non ESBLs producing strains was compared. ESBLs producing strains were resistant to piperacillin, cefoperazone and ceftriaxone. The drug resistance rate of ceftazidime and aztreonam was significantly higher than that of non-producing ESBLs strains (P < 0.05). TEM type genes were found in plasmid DNA and chromosome DNA of 20 strains of Pseudomonas aeruginosa. OXA-10 type gene was detected in plasmid DNA of 4 strains of Pseudomonas aeruginosa and OXA-10 type gene was found in DNA of 2 strains of bacteria. TEM type gene and OXA-10 type gene were detected in plasmid DNA of one strain of bacteria. Conclusion the drug resistance of Pseudomonas aeruginosa to antibiotics in our hospital is different from that in other regions of China. The ESBLs production rate of Pseudomonas aeruginosa infection in our hospital is higher. TEM type enzyme and OXA-10 type enzyme were detected, and TEM type enzyme was more frequently. Pseudomonas aeruginosa encodes ESBLs gene on plasmid DNA and also on chromosome DNA. The resistance of Pseudomonas aeruginosa to the third generation of cephalosporins was complex and diverse, and the mechanism of resistance to the third generation cephalosporins was mainly ESBLs production. Diagram [11 / Table. [7] reference. [54]
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2007
【分类号】：R378.99

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