下呼吸道感染病原菌分布及耐药性分析

目的了解下呼吸道感染疾病常见致病菌的分布情况及抗菌药耐药情况,为临床合理使用抗菌药物提供依据。方法收集2009年5月至2011年5月下呼吸道感染患者合格痰标本进行细菌学培养、鉴定及药敏试验分析。结果下呼吸道感染住院患者痰液培养所分离409株非重复的致病菌株,革兰阴性杆菌是主要致病菌,革兰阴性杆菌216株(52.8%),其中铜绿假单胞菌78株(19.1%)位居第一,其次是肺炎克雷伯杆菌42株(10.3%),大肠埃希菌17株(4.2%)。肺炎克雷伯菌、大肠埃希菌超广谱β-内酰胺酶(ESBLs)阳性率分别为38.1%、64.7%。非发酵阴性杆菌106株(25.9%),铜绿假单胞菌78株,不动杆菌13株。革兰阳性球菌22株(5.4%),葡萄球菌属21株,金黄色葡萄球菌7株(1.7%),耐甲氧西林金黄色葡萄球菌(MRSA)4株,检出率为57.1%,凝固酶阴性的葡萄球菌14株,耐甲氧西林凝固酶阴性的葡萄球菌(MRCNS)10株,检出率为71.4%。真菌171株(41.8%),多数革兰阴性杆菌对阿米卡星、左氧氟沙星有很高敏感率;革兰阳性球菌尤其是耐甲氧西林金葡菌对青霉素、左氧氟沙星等耐药,但对万古霉素敏感。结论医院下呼吸道感染以革兰阴性杆菌为主,不同的细菌对同一抗菌药物的敏感差异较大,铜绿假单胞菌耐药情况呈上升趋势,应根据药敏结果选择抗菌药物。

Pathogens distribution in lower respiratory tract infections and analysis of drug resistance

Objective To investigate the pathogens distribution in lower respiratory tract infections and antimicrobial resistance status to provide reference for rational use of antimicrobials in clinic.Methods Bacterial culture of the qualified sputum samples from the patients admitted from May,2009 to May 2011 was performed.The bacteria identification and drug sensitivity tests were done by ATB system.Results Totally 409 strains of bacteria were isolated,the dominant was Gram-negative bacilli（52.8%）.Among them,Pseudomonas aeruginosa accounted for 19.1%,Klebsiella pneurnoniae for 10.3% and Escherichia coli for 4.2%.The ESBLs positive rate of Escherichia coli,Klebsiella pneumoniae were 38.1% and 64.7% respectively.106 strains were nonfermenters Gram-negative bacilli,78 strains were Pseudornonas aeruginoa and 13 strains were Acinetobacter.The Gram-positive bacteria were 22 strains.21 strains were staphylococcus and 7 strains were S.aureus and 14 strains were coagulase-negative Staphylococcus with the detection rate of 71.4%.Fungi were 171 strains（41.8%）.Most of Gram-negative bacilli were highly sensitive to amikacin and levofloxacin.Conclusion The dominant pathogenic bacteria in lower respiratory tract infection in our area are Gram-negative bacteria.Different bacteria have the different sensitivities to the same antimicrobial agent.The drug resistant rate of Pseudornonas aeruginoa keeps anupward tendency.We should select antibiotics according to the results of drug sensitivity test.