鲍曼不动杆菌的耐药监测及rapd基因分型意义研究

Monitoring of the drug resistance of Acinetobacter baumannii and the significance of rapd genotyping

目的分析鲍曼不动杆菌的耐药监测以及rapd基因分型的意义,为合理用药及防控鲍曼不动杆菌院内感染提供参考依据。方法选择2014年5月-2016年4月间本院分离自住院患者不同标本的鲍曼不动杆菌620株(均为不重复菌株),采用全自动微生物分析仪(WalkAway-96SI)与纸片扩散法进行菌种鉴定及药敏试验,应用rapd技术对其中58株多重耐药鲍曼不动杆菌进行基因分型。结果 620株鲍曼不动杆菌耐药情况较重,其中对头孢哌酮/舒巴坦、左氧氟沙星耐药率分别为20.16%(125/620)和45.81%(284/620),对多粘菌素B均敏感;对其余13种抗菌药物耐药率均>56%。在620株菌株中多重耐药检出率为76.45%(474/620)。ICU与非ICU患者感染鲍曼不动杆菌对13种抗菌药物的耐药率(22.22%87.44和16.50%57.28%)比较差异统计学有意义(P<0.01);rapd技术分出8种类型基因:A-H,其中A型22株,B型12株,C型6株,D型8株,E型4株,F型3株,G型2株,H型1株。结论鲍曼不动杆菌的耐药情况较严重,呈逐年上升趋势,且存在多重耐药。rapd基因分型有助于细菌的同源性分析,可为防控院内感染提供依据。

Objectives To monitor the drug resistance of Acinetobacter baumannii and to examine the significance of rapd genotyping in order to provide a direct and reliable reference for the rational use of drugs and the control of nosocomial infections with A.baumannii. Methods Six hundred and twenty strains of A.baumannii that were isolated from patients at this Hospital from May 2014-April 2016 were studied.Strains were obtained from different specimens and none of the strains were duplicated.An automated microbial analyzer（WalkAway-96SI）was used to identify strains and susceptibility testing was performed using the disk diffusion method.The rapd technique was used to genotype 58 strains of multi-drug resistant A.baumannii. Results The 620 strains of A.baumannii mainly came from samples including the respiratory tract,blood,wound pus,cerebrospinal fluid,pleural and peritoneal effusions,and sterile body fluids.Patients infected with A.baumannii were mainly from the Neurology ICU,the general ICU,the burn unit,Neurology,Respiratory Medicine,and Surgery.Drug susceptibility testing indicated the 620 strains of A.baumannii were highly drugresistant;their resistance to cefoperazone/sulbactam was 20.16%（125/620）and their resistance to cefoperazone/sulbactam was 45.81%（284/620）.Strains were sensitive to polymyxin B,but their resistance to 13 other antimicrobials was56%,and multi-drug resistance was detected at a rate of 76.45%（474/620）.The resistance of A.baumannii infecting patients in an ICU and patients in some other unit or ward differed significantly（P〈0.01）.The rapd technique identified8 genotypes,A-H.Of the 620 strains of A.baumannii,22 strains were genotype A,12 were genotype B,6were genotype C,8were genotype D,4were genotype E,3were genotype F,2were genotype G,and 1was genotype H. Conclusion At this Hospital,A.baumannii is highly drug-resistant.This resistance has increased annually,and A.baumannii is becoming multi-drug-resistant.rapd genotyping helps to analyze the homology of bacteria and it can provide evidence for control of nosocomial infections.