大肠埃希菌血流感染的临床特点分析

The clinical characteristics analysis of Escherichia coil bloodstream infection

目的探讨大肠埃希菌血流感染的临床特点。方法回顾性分析苏州大学附属第一医院2007年1月至2014年12月628例大肠埃希菌血流感染患者的基础疾病、药敏结果、血培养时的体温、血常规、深静脉置管、治疗及转归情况。按常规方法进行细菌分离、鉴定，细菌药物敏感试验采用Kirby—Bauer纸片扩散法。结果628例患者均有至少1项基础疾病，多数基础疾病为恶性血液病、恶性实体肿瘤、肺部感染等。体温正常40例（6．4％），发热587例（93．5％），低温1例；白细胞减少252例（40．1％），中性粒细胞减少237例（37．7％），其中粒细胞缺乏者216例。628株大肠埃希菌药敏结果中，对亚胺培南的总耐药率最低，为3．3％。所有病例中，检出产超广谱B一内酰胺酶（ESBLs）大肠埃希菌338例（53．8％）。ESBLs阳性大肠埃希菌对复方磺胺、氨苄西林、庆大霉素、头孢唑啉、头孢呋辛、头孢噻肟、头孢曲松、头孢吡肟、头孢他啶、头孢哌酮、哌拉西林及环丙沙星的耐药率分别为80．2％、100．0％、62．4％、99．1％、99．1％、98．8％、98．2％、48．5％、50．6％、95．0％、98．2％、79．6％，者B高于ESBLs阴性大肠埃希菌的67．9％、79．7％、47．6％、50．0％、47．2％、41．0％、40．3％、27．2％、24．1％、40．0％、56．2％、58．3％，差异均有统计学意义（x^2=12．33、75．90、13．92、209．00、224．94、259．25、256．59、27．79、46．19、222．85、165．08、33．59，均P〈0．05）。628例患者中，有178例患者在血培养前有深静脉导管置入的侵入性操作。所有病例均采用相应抗菌药物治疗，主要包括碳青霉烯类及β-内酰胺酶抑制剂复合制剂，其中好转533例，好转率为84．9％。结论大肠埃希菌血流感染的发生具有多种危险因素，ESBLs阳性大肠埃希菌耐药率较ESBLs阴性大肠埃希菌高，临床用药应根据患者的药敏情况制定合理治疗方案。

Objective To explore the clinical features of Escherichia coli bloodstream infection. Methods . The clinical data of underlying diseases, antimicrobial susceptibility, temperature at blood sampling, results of routine blood tests, venous catheterization, therapy and prognosis of Escherichia coli bloodstream infection in the First Affiliated Hospital of Soochow University from January 2007 to December 2014 were analyzed retrospectively. The pathogens were routinely isolated and identified. Susceptibilities against antimicrobial agents were determined by Kirby-Bauer methods. Results All patients had at least one underlying disease. Most of the basic diseases were hematological malignancies, malignant solid tumors, pneumonia and so on. Body temperature was normal in 40 patients （ 6. 4% ） , fever in 587 patients （93.5%） and low temperature in 1 patient. There were 252 patients with leukopenia （40. 1%）, 237 patients with granulocytopenia （ 37. 7% ） and 216 patients with agranulocytosis. The resistance rate to imipenem was 3.3% , which was the lowest among the total antimicrobial susceptibilities of 628 Escherichia Coli. The extended-spectrum-β-lactamase （ESBL）-producing strains accounted for 53.8% among the total patients. The resistance rates of ESBLs-producing-Escherichia coli for the Sulfamethoxazole, Ampicillin, Gentamicin, Cefazolin, Cefuroxime, Cefotaxime, Ceftriaxone, Cefepime, Ceftazidime, Cefoperazone, Piperacillin and Ciprofloxacin were 80.2% , 100.0% , 62.4% , 99. 1% , 99. 1% , 98.8% , 98.2% , 48.5%, 50.6%, 95.0%, 98.2%, 79.6%, respectively, which were higher than that of non-ESBLs- producing-Escherichia coli （67.9%, 79.7%, 47.6%, 50.0%, 47.2%, 41.0%, 40.3%, 27.2%, 24.1%, 40.0%, 56.2%, 58. 3%, respectively）, the differences were significant statistically （ x^2 = 12.33, 75.90, 13.92, 209.00, 224.94, 259.25, 256.59, 27.79, 46.19, 222.85, 165.08, 33.59, allP 〈 0.05 ）. One hundred and seventy eight patients received venous catheterization when blood culture were performed. All the patients received antimicrobial treatment, mainly including carbapenem antibiotics and beta-lactamase inhibitors combinations. Of which 533 patients were improved, the improvement rate was 84.9%. Conclusions There are many risk factors in relation to Escherichia coli bloodstream infection. The antimicrobial resistance rate of ESBLs-producing-Escherichia coli is higher than that of none-ESBLs- producing-Escherichia coll. Individualized strategies should be based on antimicrobial sensitivity.