下呼吸道铜绿假单胞菌血清分型及体外抗菌活性分析

Serotype of Pseudomonas Aeruginosa in Lower Respiratory Tract and Analysis on Antibacterial Activity in Vitro

目的了解临床下呼吸道感染标本中的铜绿假单胞菌的血清分型及耐药性。方法常规分离培养细菌,获纯培养后用VITEK微生物全自动分析仪或API系统鉴定到种;血清分型按试剂盒操作说明进行;药敏实验采用KB纸片扩散法,按NCCLS规定的标准进行;ESBLs检测采用表型确认法,AmpC酶检测采用三维实验确认法。结果75株铜绿假单胞菌分型率为89.3%,B型占57.3%,次为G型和E型分别为6.7%和5.3%;对11种抗菌药物的耐药率为:头孢曲松74.7%、阿洛西林45.5%、替卡西林克拉维酸58.7%、左氧氟沙星53.3%、哌拉西林56.6%、阿米卡星54.7%、头孢哌酮46.7%、亚胺培南西拉司丁42.6%、头孢吡肟33.3%、头孢他啶22.7%、头孢哌酮舒巴坦9.3%;产ESBLs的阳性率为38.7%,产AmpC的阳性率为14.7%。结论铜绿假单胞菌血清型以B型为主,次为G型和E型;该菌耐药现象日趋严重,对非产酶菌的治疗根据药敏实验结果可选用头孢吡肟、头孢他啶、头孢哌酮舒巴坦、亚胺培南西拉司丁,对产酶菌应与阿米卡星、左氧氟沙星等抗菌药物联用。

Objective To realize the serotypes of pseudomonas aeruginosa in lower respiratory tract infection samples and their drug resistance. Methods Bacteria which had been routinely isolated and cultured were identified down to species by VITEK microorganism auto-analyzer or API system. Serotype were identified according to the manual of the kit. Drug susceptivity tests were done using Kirby - Bauer disc diffusion method on the basis of NCCLs standard. Phenotype confirmation method and three-dimensional experiment confirmation method were respectively used in extended spectrum lactamase （ESBLs） and AmpC enzyme tests. Results Of the 75 strains, 89.3% were serotyped. Serotype B, G and E respectively accounted for 57.3% , 6.7% and 5.3%. The rates of resistance to various drugs were listed as follow：74.4% （ceftriaxone） , 45.5% （azlocillln） , 58.7% （ ticarcilin - clavulanat） , 53.3% （levofloxacin） , 56.6% （piperacillin） , 54.7% （amikacin） , 46.7% （cefoperazone） , 42.6% （imipenem-cilastatin） , 33.3% （cefepime） , 22.7% （ceftazidime） and 9.3% （cefoperazone-snlbactam）. The ESBLs-producing rate was 38.7% , and The AmpC enzym-producing rate was 14.7 %. Conclusion The serotypes of pseudomonas aeruginosa are mainly type B, and then type G and E. The bacterium＇s resistance to drugs is becoming increasingly wide.