防污染毛刷刷检物的病原菌分布及耐药性分析

Distribution and drug resistance of pathogenic bacteria from protected specimen brush

目的了解本院下呼吸道感染患者的病原菌构成和耐药情况,为临床合理使用抗菌药物提供依据。方法取我院2011年1月—2014年12月以纤维支气管镜防污染毛刷采集的刷检物,采用法国生物梅里埃公司提供的VITEK-2 Compact微生物分析仪进行菌株鉴定及药敏试验,分析其分布及耐药情况,选择耐药菌株通过PCR分析其耐药基因。结果在244份送检标本中,检出病原菌196株,其中革兰阴性杆菌占94.9%,革兰阳性球菌占5.1%;分布前4位的病原菌为铜绿假单胞菌、鲍曼不动杆菌、肺炎克雷伯菌、嗜麦芽寡养单胞菌,分别占29.6%、19.4%、12.2%、11.7%;病原菌主要来源于呼吸科、ICU、神经外科、免疫血液科、神经内科;病原菌对抗菌药物的耐药性较严重,铜绿假单胞菌对阿米卡星、哌啦西林/三唑巴坦、亚胺培南、头孢他啶的耐药率分别为13.8%、15.5%、17.2%、18.9%;鲍曼不动杆菌除对米诺环素和头孢哌酮/舒巴坦耐药率分别为18.4%和21.1%外,对其他抗菌药物的耐药率均大于50.0%;产超产谱β-内酰胺酶(ESBLs)的肺炎克雷伯菌阳性率为41.7%;嗜麦芽寡养单胞菌对米诺环素、左氧氟沙星、复方复方磺胺甲噁唑、头孢哌酮/舒巴坦的耐药率分别为4.3%、13.0%、17.4%、21.7%,PCR结果显示:某些耐药菌株存在耐药基因。结论下呼吸道感染的主要病原菌为革兰阴性杆菌,检出病原菌对抗菌药物的耐药性较强,且某些耐药菌株存在耐药基因,临床医生应根据细菌培养和药敏结果采取防治措施。

Objective To explore the distribution and drug-resistance of pathogenic bacteria causing lower respiratory tract infections from protected specimen brush to put forward suggestions for clinical medication. Methods The retrospective analysis was conducted on distribution and drug-resistance profile of the specimens collected from the fiberoptic bronchoscopes with the use of pollution prevention brush from January 2011 to December 2014. Resistance genes was analyzed by PCR. Results In 244 detected specimens, 196 pathogenic strains were isolated, including 186 strains of Gram-negative bacilli（94.9%）, 10 strains of Gram-positive cocci（5.1%）. The top four pathogens were Pseudomonas aeruginosa（58 isolates, 29.6%）, Acinetobacter baumannii （38 isolates, 19.4%）, Klebsiella pneumoniae （24 isolates, 12.2%） and Stenotrophomonas maltophilia （23 isolates, 11.7%）. The pathogens were mainly isolated from the department of respiratory, ICU, neurosurgery, immune-blood and neurology. The drug resistance rates of P. aeruginosa strains to amikacin, piperacillin-tazobactam, imipenem and ceftazidime were 13.8%, 15.5%, 17,2% and 18.9% respectively. The drug resistance rates of A. baumannii strains to all the antibiotics tested were above 50.0% except minocycline（18.4%） and cefoperazone-sulbactam（21.1%）. The positive rates of extended- spectrumβ-1actamase（ESBLs）-producing K. pneumoniae was 41.7%. The drug resistance rates of X maltophilia strains to minocycline, levofloxacin trimethoprim-sulfamethoxazole, cefoperazone-sulbactam were 4.3%, 13.0%, 17.4% and 21.7% respectively. PCR Results showed that： some resistant strains exist drug resistance genes. Conclusion The pathogens of the lower respiratory tract infection are mainly Gram-negative bacilli, the detected bacteria have a high resistance to antibacterial agents, meanwhile some resistant strains exist drug resistance genes. Doctors should take the preventive measures according to the results of bacteria culture and dru~ sensitive tests.