肿瘤患者下呼吸道感染常见病原菌的分布与耐药性研究

目的 研究肿瘤患者下呼吸道感染常见病原菌的分布与耐药现状,为临床合理使用抗菌药物提供科学依据.方法对2 037例下呼吸道感染肿瘤患者深部咳出的痰标本,按照<全国临床检验操作规程>进行病原菌分离、鉴定,药敏试验采用纸片扩散法(K-B法),并按 CLSI/NCCLS规定的标准进行.结果 病原菌的阳性检出率为70.3%,其中G-杆菌占40.9%,G+球菌占29.5%,真菌占28.7%;大肠埃希菌、凝固酶阴性葡萄球菌(CNS)和白色假丝酵母菌分别为G-杆菌、G+球菌和真菌的首位;大肠埃希菌和肺炎克雷伯菌产超广谱β-内酰胺酶(ESBLs) 菌株分别为52.7%和30.8%,阴沟肠杆菌产AmpC酶菌株占16.9%,铜绿假单胞菌产金属β-内酰胺酶(MBL)菌株占9.8%;甲氧西林耐药株分别占金黄色葡萄球菌(SAU)和CNS的38.3%和70.5%,未发现万古霉素耐药的耐甲氧西林SAU(MRSA)和耐甲氧西林CNS(MRCNS);万古霉素、碳青霉烯类药物仍然分别是G+球菌和肠杆菌科细菌最敏感的药物.结论 本院肿瘤患者下呼吸道感染以白色假丝酵母菌位居第一,对伊曲康唑耐药性较严重;细菌耐药性以产ESBLs大肠埃希菌、肺炎克雷伯菌,产AmpC酶阴沟肠杆菌,产MBL铜绿假单胞菌,鲍曼不动杆菌,MRSA和MRCNS比较严重,其他细菌也分别存在不同程度的耐药情况.临床微生物实验室应继续加强耐药性检测,为临床合理选用抗菌药物提供科学依据.

Distribution and drug resistance of common pathogenic bacteria in patients with cancer and lower respiratory tract infection

Objective To study the distribution and drug resistance of common pathogenic bacteria in patients with cancer and lower respiratory tract infection to provide scientific reference for the rational use of antibacterial drug.Methods Pathogenic bacteria in 2 037 cases of sputamentum samples from patients combined with tumor and lower respiratory tract infection were isolated and identified according to National Clinical Laboratory Operating Procedures, and drug sensitive test was operated through paper diffusion method (K-B method) according to CLST/NCCLS standards.Results The positive rate of pathogen was 70.3%, with 40.9% of Gram-negative bacilli, 29.5% of Gram-positive cocci and 28.7% of fungi. E.coli, Coagulase-negative staphylococci and Candida albicans were the most common among the above three pathogens respectively. E.coli and Klebsiella pneumoniae producing extended-spectrum β-lactamases(ESBLs)was 52.7% and 32.8% respectively, and Cloacae producing AmpC was 16.9%, Aeruginosa producing Metalloenzymes(MBL)was 9.8%. The percentages of methicillin-resistant strains in Staphylococcus aureus and coagulase-negative staphylococci were 38.3% and 70.5% respectively. Vancomycin resistant MRSA and MRCNS were not found. The Gram-positive cocci and Enterobacteriaceae was most sensitive to vancomycin and carbapenem respectively.Conclusion The main pathogens in sputamentum samples of tumor patients with lower respiratory tract infection in this hospital was Candida albicans. which was highly resistant to itraconazole, and the drug resistance of the E.coli and Klebsiella pneumoniae producing ESBLs, Cloacae producing AmpC, Aeruginosa producing MBL, Acinetobacter baumannii, MRSA and MRCNS were serious. Some other pathogens also existed drug resistance of varying degree, except above-mentioned pathogens. So microbiology laboratory should continue to enhance the detection of drug resistance, and provide scientific basis for the clinical use of drug reasonably.