【作者】 陈佳红；

【导师】 罗兵；

【作者基本信息】 青岛大学 ， 病原生物学， 2012， 硕士

【摘要】 目的了解临床常见革兰阴性杆菌分离菌株对常用抗菌药物的耐药现状及其抗消毒剂基因的携带情况,为临床治疗感染性疾病提供科学依据。方法采用BD Phoenixl00全自动微生物分析仪鉴定细菌；药敏试验采用K-B琼脂纸片扩散法；聚合酶链反应(PCR)检测抗消毒剂基因和磺胺耐药基因(qacEΔ1-sull)。结果①临床共分离208株革兰阴性杆菌,其中大肠埃希菌49株,肺炎克雷伯菌53株,阴沟肠杆菌10株,铜绿假单胞菌48株,鲍曼不动杆菌48株。主要分布于ICU、呼吸科、肾内科、老年内科和神经科病房,不同细菌在不同科室分布有差别。②临床常用抗生素中,肠杆菌科临床分离菌株耐药率低于20%的抗生素有阿米卡星、亚胺培南、美洛培南、哌拉西林/他唑巴坦和头孢哌酮/舒巴坦；耐药率高于80%的抗生素有氨苄西林。③临床分离的非发酵菌菌株中,铜绿假单胞菌耐药率低于30%的抗生素有阿米卡星、妥布霉素、哌拉西林/他唑巴坦和头孢哌酮/舒巴坦；耐药率高于90%的抗生素有头孢唑林、头孢呋肟、氨苄西林、氨苄西林/舒巴坦和呋喃妥因。鲍曼不动杆菌对抗生素的耐药水平普遍较高,耐药率低于45%的抗菌药物有哌拉西林/他唑巴坦和头孢哌酮/舒巴坦。耐药率高于90%的抗菌药物有头孢唑林、头孢呋肟和呋喃妥因。④208例革兰阴性杆菌分离菌株中,有104株携带qacE△1-sull基因,总阳性率为50%。其中鲍曼不动杆菌中携带qacE△1-sull基因阳性率高达75%,其次是大肠埃希氏菌为69.4%,2种菌株qacE△1-sull基因携带率明显高于其它菌株(P<0.05)。⑤各科室中,ICU检出携带qacEΔ1-sull基因革兰阴性杆菌42株,阳性率高达71.2%,明显高于呼吸科和神经科菌株的携带率(P<0.05)。结论①ICU病房是常见革兰阴性杆菌分布较高的科室,提示免疫力低下、使用呼吸机、行气管插管等侵入性操作的患者以及长期住院使用抗菌药物治疗的患者应密切注意革兰阴性杆菌等条件致病菌引起的感染。②肠杆菌科中大肠埃希氏菌和肺炎克雷伯菌多重耐药严重,亚胺培南和美洛培南仍是治疗大肠埃希菌和肺炎克雷伯菌感染的首选药物,抗生素复合制剂头孢哌酮/舒巴坦也是治疗大肠埃希氏菌和肺炎克雷伯菌感染的理想药物。③非发酵菌中铜绿假单胞菌和鲍曼不动杆菌对常用抗生素呈高水平耐药,哌拉西林/他唑巴坦和头孢哌酮/舒巴坦对治疗二者感染有较好效果。④革兰阴性杆菌临床分离菌株qacEΔ1-sull基因携带率较高,以鲍曼不动杆菌和大肠埃希菌尤为明显,因此应加强对多重耐药菌株的耐药性监测,重视抗菌药物和医用消毒剂的使用。更多还原

【Abstract】 Objective:To investigate the drug resistance of common gram-negative bacilli to regular antibiotics and detect the disinfectant-resistant genes, providing a scientific basis for clinical treatment of infectious diseases.Methods:All isolated strains were identified by BD Phoenix automated microbiology system (BD Phoenix100). Antibiotic sensitivity analysis of the isolated strains were taken by Kirby-Bauer method, and the disinfectant-resistant gene (qacEΔ1-sull) was detected by polymerase chain reaction (PCR).Results:①208gram-negative bacilli were isolated from clinical specimens, including Escherichia coli (49strains), Klebsiella pnenmoniae(53strains), Enterobacter cloacae(10strains), verdigris Pseudomonca (48strains) and Acinetobacter baumannii(48strains), which were mainly distributed in intensive care unit (ICU), respiratory and neurological department.②Among the commonly used antibiotics in clinical treatments, the drug resistance rates of enterobacteria to Amikacin, Imipenem, Meropenem, Piperacillin/Tazobactam and Cefoperazone/Sulbactam were less than20%, while the rate to Ampicillin was higher than80%.③Among the isolated non-fermentative bacteria, the resistance rates of verdigris Pseudomonca to Amikacin, Tobramycin, Piperacillin/Tazobactam and Cefoperazone/Sulbactam were less than30%. while the resistance rates to Cefazolin, Cefuroxime, Ampicillin. Ampicillin/Sulbactam and Nitrofurantoin were higher than90%. Moreover, drug resistance of Acinetobacter baumannii was strictly high. To Piperacillin/Tazobactam and Cefoperazone/Sulbactam the rates were less than45%, while to Cefazolin, Cefuroxime and Nitrofurantoin, the rates were more than90%.④The104out of208(50%) strains carried qacEΔ1-sull gene detected by PCR. The positive rate of Acinetobacter baumannii carrying qacEA1-sull gene that was the highest (75%). Escherichia coli was69.4%. The positive rate of Acinetobacter baumannii and Escherichia coli carrying qacEAl-sull gene were higher than other bacteria strains(P<0.05).⑤The42strains carrying qacEΔ1-sull gene out of208(71.2%) strains in ICU were identified, which was obviously higher than respiratory and neurological department(P<0.05). Conclusions:①mong all the departments, the distribution of gram-negative bacilli from ICU is the highest, suggesting that patients in ICU with poor immunity, using ventilator or receiving invasive operations like tracheal intubation and taking antibiotics for a long time should be paid more attention to the infection of gram-negative bacilli.②Escherichia coli and Klebsiella pnenmoniae (belonging to enterobacteria) are severely muti-drug resistant, but Imipenem and Meropenem are still the first choice to treat infections of Escherichia coli and Klebsiella pnenmoniae.③Verdigris Pseudomonca and Acinetobacter baumannii (belonging to non-fermentative bacteria) are highly resistant to common antibiotics, while their infections can be effectively treated by Piperacillin/Tazobactam and Cefoperazone/Sulbactam.④Among the isolated gram-negative bacilli, the positive rate of qacEAl-sull gene is high, especially Verdigris Pseudomonca and Escherichia coli, indicating that the usage of antibiotics and disinfectants should be more strictly controlled.更多还原