老年下呼吸道感染患者的病原菌分布与耐药性分析

目的分析60岁以上老年下呼吸道感染者分离病原菌的分布规律及其耐药性特点,以指导临床合理用药。方法采用API系统进行菌种鉴定,采用K-B法进行药敏实验,采用纸片扩散表型确证法进行超广谱β-内酰胺酶(ES-BLs)测定。结果 826株病原菌中G-杆菌最多,为506株(61.26%),主要是鲍曼不动杆菌(115株),肺炎克雷伯菌(104株)和铜绿假单胞菌(99株);真菌237株,占28.69%,主要是白色假丝酵母菌(153株);G+球菌83株(10.05%),主要是金黄葡萄球菌(51株)。G-杆菌对碳青霉烯类(美罗培南)及氟喹诺酮类(环丙沙星/左氧氟沙星)抗生素较敏感,而对头孢类耐药率较高;白色假丝酵母菌对两性霉素B的耐药率最低;金黄葡萄球菌对强力霉素和氯霉素耐药率较低,未发现万古霉素耐药株。结论老年下呼吸道感染患者的主要病原菌仍以G-杆菌为主,真菌感染明显增多;分离菌多重耐药现象严重,耐药性监测重要性凸显。

Analysis of pathogen distribution and drug resistance in elderly patients with a lower respiratory tract infection

Objective To investigate the distribution and drug resistance of pathogenic bacteria from elderly patients with a lower respiratory tract infection to provide a basis for the rational use of antibiotics.Methods Clinical isolates were identified with the API system and their drug resistance was tested using the K-B method.Detected ESBL-producing strains were confirmed by the disc diffusion method.Results A total of 826 strains,including Gram-negative bacteria(506 strains,61.26%),fungi(237 strains,28.69%),and Gram-positive bacteria(83 strains,10.05%),were collected.The 5 pathogens with the highest rates of isolation were Candida albicans(153 strains),Acinetobacter baumannii(115 strains),Klebsiella pneumoniae(104 strains),Pseudomonas aeruginosa(99 strains),and Staphylococcus aureus(51 strains).Gram-negative bacteria were relatively sensitive to carbapenems and fluoroquinolones but relatively resistant to cephalosporins.C.albicans was more sensitive to amphotericin B.Staphylococcus aureus was sensitive to vancomycin,doxycycline,and chloramphenicol.None of the isolates were resistant to vancomycin.Conclusion Gram-negative bacilli are still the predominant pathogens in elderly patients with a lower respiratory tract infection.Fungal infections have increased markedly.Monitoring drug resistance is clearly crucial.