尿路感染的病原菌分布与耐药性分析

Distribution and drug resistance of pathogens causing urinary tract infections

目的分析2006-2010年医院尿路感染病原菌的构成及耐药谱的动态变化,以指导临床医师合理应用抗菌药物。方法收集2006年1月-2010年12月临床分离的尿液标本,细菌鉴定及药敏试验采用全自动细菌生化分析仪(VITEK-2Compact);根据CLSI 2010年标准,利用WHONET5.6软件分析病原菌的分布及耐药情况。结果共分离出病原菌1945株,其中革兰阴性菌1179株,占60.6%,革兰阳性菌483株,占24.8%,真菌283株,占14.6%;检出的前几位病原菌依次为大肠埃希菌、屎肠球菌、铜绿假单胞菌、肺炎克雷伯菌、白色假丝酵母菌、粪肠球菌和凝固酶阴性葡萄球菌;主要分布于肾内科(16.9%)、干部科(14.5%)、内分泌科(12.2%)、重症监护病房(6.3%)、呼吸科(6.1%)和泌尿外科病房(6.1%);屎肠球菌对多数抗菌药物的耐药率均高于粪肠球菌;屎肠球菌对万古霉素耐药率为16.3%;金黄色葡萄球菌和凝固酶阴性葡萄球菌中耐甲氧西林菌株检出率分别为65.6%和77.4%,未发现葡萄球菌属对万古霉素、替考拉宁和利奈唑胺的耐药菌株;大肠埃希菌和肺炎克雷伯菌产ESBLs的检出率分别为58.8%和38.6%;发现1株大肠埃希菌和2株肺炎克雷伯菌对亚胺培南耐药菌株;多药耐药(MDR)的铜绿假单胞菌和鲍氏不动杆菌分别占13.8%和43.2%。结论大肠埃希菌为泌尿系感染的主要病原菌;女性患者明显高于男性;真菌引起的尿路感染有明显上升的趋势;过去常用于治疗泌尿系感染的喹诺酮类抗菌药物,耐药性较高,临床应根据药敏试验结果,合理选择抗菌药物。

OBJECTIVE To analyze the pathogenic bacteria distribution and their susceptibility to antimicrobial drugs in clinical cases with urinary tract infection conformed by urine culture,and to guide clinically the selection of the reasonable antibiotics.METHODS The clinical samples from urine were collected from Jan 2006 to Dec 2010 in the First Affiliated Hospital of Chinese People′s Liberation Army General Hospital.Antimicrobial susceptibility test was performed by VITEK2 COMPACT.The susceptibility,resistance and intermediate were analyzed according to standards of CLSI（2010）.WHONET5.6 software was used to analyze the data.RESULTS A total of 1945 non-repetitive bacterial isolates were collected.The proportion of gram-negative bacillus was 60.6%（Escherichia coli accounted for 35.5%）;the proportion of gram-positive cocci bacterium was 24.8%（Enterococcus facium accounted for 14.6%）,and fungus was 14.6%.The top seven isolated bacteria were E.coli,E.facium,Pseudomonas aeruginosa,Klebsiella pneumonia,Candies albicans,E.faecalis and coagulase negative Staphylococcus.Of the admitted patients,most patients were from nephrology wards（16.9%）,followed by Medical department for senior cadres wards（9%）,endocrinology wards（12.2%）,ICU patients（123,6.3%）,respiratory wards（6.1%） and urology wards（118,6.1%）.Test results showed drug resistance rate of E.facium was higher than E.faecalis to common antibiotics.16% isolates of E.facium in this surveillance were resistant to vancomycin,2% resistant to linezolid and 1.2% intermediate to teicoplanin.The detection rates of methicillin-resistant Staphylococcus aureus（MRSA） and coagulase negative Staphylococcus（MRCNS） were 65.6% and 77.4%.No isolates of Staphylococci were found to be resistant to vancomycin.ESBLs-producing strains accounted for 58.8% and 38.6% in E.coli and Klebsiella spp.,respectively.Two isolates of K.pneumonia and one isolate of E.coli were resistant to imipenem.13.8% of P.aeruginosa isolates and 43.2% of-Acinetobacter baumannii isolates showed multi-drug resistance. CONCLUSION E.coli is still the main pathogenic bacteria causing urinary tract infection.There are more females than males.The fungi with drug resistance are increasing by year.There is increasing resistance to fluorquinolones in bacteria isolated from urine,pointing out clinicians should select the antibiotics to use rationally according to the drug susceptibility test.