血液病住院患者血培养分离菌的分布及耐药性分析

Distribution and antibiotic resistance of the pathogens isolated from blood of the inpatients in hematology ward

目的了解血液科病房血培养分离病原菌的分布及其耐药现状。方法药敏试验采用纸片扩散法。用WHONET5.6软件进行数据分析。结果共分离出521株病原微生物,其中革兰阴性菌47.2%,革兰阳性菌45.7%,真菌7.1%。主要为凝固酶阴性葡萄球菌154株、大肠埃希菌88株、肺炎克雷伯菌51株、铜绿假单胞菌39株和肠球菌属34株。肺炎克雷伯菌和大肠埃希菌超广谱β内酰胺酶(ESBL)阳性率分别为40.4%和63.4%。大肠埃希菌对美罗培南、亚胺培南敏感率>90%,对哌拉西林-他唑巴坦敏感率>70%;肺炎克雷伯菌对美罗培南、亚胺培南敏感率>85%,对左氧氟沙星、哌拉西林-他唑巴坦的头孢哌酮-舒巴坦的敏感率>70%;铜绿假单胞菌对环丙沙星、妥布霉素敏感率>90%,对左氧氟沙星、美罗培南、亚胺培南、哌拉西林-他唑巴坦、头孢吡肟、头孢哌酮-舒巴坦的敏感率均>70%。凝固酶阴性葡萄球菌和肠球菌属对利奈唑胺、替考拉宁敏感率均>90%。MRCNS检出率为82.5%。检出耐碳青霉烯类大肠埃希菌3株、肺炎克雷伯菌4株和耐万古霉素肠球菌8株。结论革兰阴性菌是血液病患者血流感染主要致病菌,常见革兰阴性菌对哌拉西林-他唑巴坦、美罗培南、亚胺培南较敏感,革兰阳性菌对利奈唑胺、替考拉宁较为敏感。这对临床经验性用药具有很大指导作用。

Objective To investigate the distribution and antibiotic resistance of the pathogens isolated from blood of the inpatients in hematology ward. Methods Antimicrobial susceptibility test was carried out using Kirby-Bauer method. The data were analyzed by WHONET 5.6 software. Results Of the 521 microbial isolates collected, gram-negative bacilli accounted for 47.2%, gram- positive cocci 45.7% and fungi （7.1%）. The most frequently isolated microorganisms were coagulase negative Staphylococcus （154）, E. coli （88）, K. pneumoniae （51）, P aeruginosa （39） and Enterococcus spp （34）. ESBLs were produced in about 40.4% of the K. pneumoniae isolates and 63.4% of the E. coli isolates. At least 90% of the E. coli isolates were susceptible to imipenem and meropenem, and at least 70% susceptible to piperacillin-tazobactam. At least 85% of the K. pneumoniae strains were susceptible to imipenem and meropenem, and at least 70% susceptible to levofloxacin, piperacillin-tazobactam and cefoperazone-sulbactam. The percentage of the P aeruginosa susceptible to ciprofloxacin and tobramycin was at least 90%, and higher than 70% to levofloxacin, meropenem, imipenem, piperacillin-tazobactam, cefepime, and cefoperazone-sulbactam. More than 90% strains of the coagulase negative Staphylococcus and Enterococcus were susceptible to linezolid and teicoplanin. Overall, 82.5% of the coagulase negative Staphylococcus isolates were resistant to methicillin. Three E. coli isolates and 4 K. pneumoniae isolates were found resistant to carbapenems, and 14 Enterococcus isolates were resistant to vancomycin. Conclusions Gram-negative bacilli are the major pathogens from blood samples in hematology ward, which show high susceptibility to piperacillin-tazobactam and cefoperazone-sulbactam, imipenem and meropenem. The gram-positive cocci show high susceptibility to linezolid and teicoplanin. These data are helpful for empirical antimicrobial therapy.