【作者】 刘刚；

【导师】 蔡绍曦；

【作者基本信息】 南方医科大学 ， 内科学， 2010， 硕士

【摘要】 背景铜绿假单胞菌属非发酵革兰阴性杆菌,在自然界广泛存在。铜绿假单胞菌属于人类条件致病菌,破坏人体正常防御机制,导致机体免疫功能低下易致本菌感染,严重者可导致败血症。我国卫生部全国细菌耐药监测网(Mohnarin)2006-2007年度数据显示在血流感染病原菌构成中铜绿假单胞菌占4.7%,在革兰阴性菌中居大肠埃希菌(18.7%)和克雷伯菌属(7.3%)之后,居第三位。在2003-2008年南方医科大学南方医院败血症患者病原菌构成中,共分离铜绿假单胞菌111株,在大肠埃希菌(190株)之后,居第二位。铜绿假单胞菌由于自身结构及抗菌药物诱导作用,该菌感染后很容易发生耐药,耐药机制复杂。并且随着抗菌药物的广泛应用,铜绿假单胞菌耐药情况日趋严重。铜绿假单胞菌败血症是临床严重的全身性感染,病情重,进展快,临床可选择的敏感抗菌药物有限,导致了铜绿假单胞菌败血症治疗困难,病死率较高。国外文献报道铜绿假单胞菌败血症病死率在21%-39%,病死率高于金黄色葡萄球菌败血症。目前国内对铜绿假单胞菌败血症的临床研究很少。目的1、分析铜绿假单胞菌败血症的细菌耐药情况。2、分析影响铜绿假单胞菌败血症患者预后的因素。方法1、收集南方医科大学南方医院2004年1月—2009年5月期间发生的铜绿假单胞菌败血症患者的临床病历资料。2、回顾性调查所有入选病例的临床病历资料,调查的内容包括所有入选患者第一次血液标本培养阳性时的时间、年龄、性别、住院科室、感染类型、感染前住院天数、住院时间、血液标本培养时间、感染前是否住ICU、合并基础疾病、留取血液标本前1周内侵入性医疗操作、留取血液标本前15天内抗菌药物的使用情况、留取血液标本前1个月内免疫抑制治疗情况、原发感染灶、败血症严重程度、实验室检查结果、第一次细菌培养阳性时的药敏试验结果。3、所有临床血液标本分离出的铜绿假单胞菌株采用美国Becton Dickinson公司的自动化细菌鉴定仪PHOENⅨ100系统进行鉴定。药敏试验采用Kirby-Bauer纸片琼脂扩散法测定。按照美国国家临床试验室标准委员会(NCCLS)文件M100-S16版的标准判断结果。根据铜绿假单胞菌对抗菌药物的敏感性,将其分为敏感、中介和耐药。4、预后评价指标：30天死亡率及生存时间。5、统计分析采用SPSS 13.0版统计软件进行汇总分析。采用χ2检验(Pearson Chi-Square或Fisher’s Exact Test)进行耐药率的比较,以P<0.05作为有显著性差异的判定标准。预后因素单因素分析：计量资料采用t检验(方差齐性),或Satterthwaite近似t检验(方差不齐)。计数资料采用χ2检验(Pearson Chi-Square或Fisher’s Exact Test),以P<0.05作为有显著性差异的判定标准。在单因素分析的基础上,选取P<0.05的因素,将单因分析中有显著性差异的变量纳入二分类非条件Logistic回归分析,采用基于最大似然估计的前进法进行二分类Logistic回归分析,计算比值比(OR)及95%的可信区间(95%CI),筛选影响铜绿假单胞菌败血症患者死亡的独立危险因素。生存时间分析：采用Kaplan-Meier法Log Rank检验比较生存时间的差异。结果1、共89例铜绿假单胞菌败血症病例入选,社区感染14例,医院感染75例。男性52例,女性37例。血液科最多,共42例,儿科其次,共10例,肾内科8例,呼吸内科6例,其他科室23例。2、铜绿假单胞菌对10种临床常用的抗假单胞菌抗菌药物的耐药率均低于30%。美罗培南的耐药率最低,为6.82%,其次是头孢哌酮/舒巴坦8.64%,阿米卡星10.11%,头孢吡肟11.11%,哌拉西林/他唑巴坦12.79%,头孢他啶13.95%,亚胺培南15.91%,环丙沙星17.07%,左氧氟沙星20.00%,氨曲南的耐药率最高,为26.79%。多药耐药率为16.85%,泛耐药率为3.37%。3、亚胺培南耐药的铜绿假单胞菌株对头孢他啶(P=0.000)、头孢吡肟(P=0.000)、头孢哌酮/舒巴坦(P=0.001)、哌拉西林/他唑巴坦(P=0.000)、环丙沙星(P=0.000)、左氧氟沙星(P=0.000)、阿米卡星(P=0.001)、美罗培南(P=0.000)的耐药率均超过35%,高于亚胺培南敏感的菌株,耐药率之间的差异有统计学意义,P<0.05。4、美罗培南耐药的铜绿假单胞菌株对头孢他啶(P=0.003)、头孢吡肟(P=0.000)、头孢哌酮/舒巴坦(P=0.000)、哌拉西林/他唑巴坦(P=0.000)、环丙沙星(P=0.000)、左氧氟沙星(P=0.000)、阿米卡星(P=0.010)、亚胺培南(P=0.000)的耐药率均超过50%,高于美罗培南敏感的菌株,耐药率之间的差异有统计学意义,P<0.05。5、亚胺培南耐药(P=0.000)与美罗培南耐药(P=0.000)的铜绿假单胞菌株的多药耐药率均高于亚胺培南敏感与美罗培南敏感的菌株,耐药率之间的差异有统计学意义,P<0.05。6、社区感染与医院感染铜绿假单胞菌株及不同性别患者感染的铜绿假单胞菌株对10种临床常用抗假单胞菌抗菌药物耐药率之间的差异无统计学意义,P>0.05。7、从血液科分离的铜绿假单胞菌株对头孢他啶(χ2=4.993,P=0.025)、头孢吡肟(P=0.032)、头孢哌酮/舒巴坦(P=0.012)、氨曲南(χ2=8.984,P=0.003)、环丙沙星(χ2=7.495,P=0.006)的耐药率均低于在其他科室分离的菌株,耐药率之间的差异有统计学意义,P<0.05。而对哌拉西林/他唑巴坦(χ2=1.877,P=0.171)、左氧氟沙星(χ2=3.013,P=0.083)、阿米卡星(P=0.163)、亚胺培南(χ2=0.158,P=0.691)、美罗培南(P=0.205)的耐药率,在血液科与其他科室分离的铜绿假单胞菌株之间无差异,P>0.05。8、从感染前曾使用碳青霉烯类抗菌药物的患者中分离的铜绿假单胞菌株对头孢他啶(P=0.000)、头孢吡肟(P=0.003)、头孢哌酮/舒巴坦(P=0.032)、哌拉西林/他唑巴坦(P=0.012)、氨曲南(P=0.008)、环丙沙星(P=0.015)、左氧氟沙星(P=0.005)、亚胺培南(P=0.000)、美罗培南(P=0.018)的耐药率均高于感染前未使用过碳青霉烯类药物的患者中分离的铜绿假单胞菌株,耐药率之间的差异有统计学意义,P<0.05。9、从感染前曾使用2种及以上抗菌药物的患者中分离的铜绿假单胞菌株的耐药率均高于感染前未使用抗菌药物或仅使用1种抗菌药物的患者中分离的铜绿假单胞菌株。10、30天内存活65例,死亡24例,30天死亡率27%。11、预后因素单因素分析结果：Pitt Bacteremia Score(χ2=-9.050, P=0.000)、血浆白蛋白(χ2=3.030,P=0.003)、留置中心静脉导管(χ2=4.113,P=0.043)、亚胺培南耐药(P=0.000)、美罗培南耐药(P=0.005)、多药耐药(P=0.000)、不适当经验性抗菌药物治疗(χ2=28.578,P=0.000)、经验性抗菌药物治疗(χ2=6.493,P=0.019)是影响铜绿假单胞菌败血症患者死亡的危险因素,死亡率之间的差异具有统计学意义,P<0.05。经验性抗菌药物单药治疗中不适当治疗占36.2%,经验性抗菌药物联合治疗中不适当治疗占14.3%,两者所占比例的差异有统计学意义,χ2=5.543,P=0.019。12、二分类非条件Logistic回归分析结果：Pitt Bacteremia Score(P=0.000,OR=4.313)和不适当经验性抗菌药物治疗(P=0.001,OR=29.471)是影响铜绿假单胞菌败血症患者死亡的独立危险因素。13、对于粒细胞缺乏患者,经验抗菌药物联合治疗和单药治疗对铜绿假单胞菌败血症患者死亡率影响的差异无统计学意义,P=0.480；对生存时间影响的差异无统计学意义,χ2=0.847,P=0.358。确诊后抗菌药物单药治疗和联合治疗对患者死亡率影响的差异无统计学意义,P=1.000；对生存时间影响的差异无统计学意义,χ2=0.036,P=0.849。14、对于非粒细胞缺乏患者,经验性抗菌药物联合治疗较单药治疗的死亡率低,两者之间的差异有统计学意义,P=0.030；经验性抗菌药物联合治疗较单药治疗的生存时间长,两者之间的差异有统计学意义,χ2=4.186,P=0.041。确诊后抗菌药物单药治疗和联合治疗对患者死亡率影响的差异无统计学意义,P=0.688；对生存时间影响的差异无统计学意义,χ2=0.348,P=0.555。结论1、南方医院铜绿假单胞菌败血症对10种临床常用的抗假单胞菌抗菌药物的耐药率均低于30%。美罗培南的耐药率最低,其次是头孢哌酮/舒巴坦,氨曲南的耐药率最高。2、亚胺培南耐药株和美罗培南耐药株对临床常用的抗假单胞菌抗菌药物的耐药率均高于敏感株,且多药耐药情况增多。3、铜绿假单胞菌败血症发病前使用碳青霉烯类抗菌药物及使用2种及以上抗菌药物均可加重铜绿假单胞菌的耐药率。4、高Pitt Bacteremia Score和不适当经验性抗菌药物治疗是影响铜绿假单胞菌败血症患者死亡的独立危险因素。5、经验性抗菌药物联合治疗可以降低不适当抗菌药物治疗的发生6、对于非粒细胞缺乏铜绿假单胞菌败血症患者,经验性抗菌药物联合治疗较单药治疗死亡率低,生存时间长。更多还原

【Abstract】 Background:Pseudomonas aeruginosa is non-fermentative gram-negative bacilli, widely exist in nature. Pseudomonas aeruginosa belongs to the human pathogens, change or damage the body’s normal defense mechanisms, resulting in lower immune function are easy to infect it, serious infection can lead to septicemia. According to the data of the Chinese ministry of bacterial resistance monitoring network(Mohnarin 2006-2007), Pseudomonas aeruginosa of 4.7% was the third proportion in gram-negative bacilli, following Escherichia coli(18.7%) and Klebsiella(7.3%). Pseudomonas aeruginosa of 111 isolates was the second, following Escherichia coli(190 isolates) in the septicemia pathogen in southern hospital since 2003-2008.Pseudomonas aeruginosa occurs resistance with complex mechanism, due to its structure and the result antimicrobial induced. The resistance status of Pseudomonas aeruginosa becomes more and more serious, along with the wide application of antimicrobial agents. Pseudomonas aeruginosa septicemia is severe systemic infection with rapid progression and high mortality. The mortality of Pseudomonas aeruginosa septicemia reported by foreign literature is between 21% and 39%, and is more than that of Staphylococcus aureus septicemia. At present domestic clinical research about Pseudomonas aeruginosa septicemia is few. Objective:1. To explore the drug resistance status of Pseudomonas aeruginosa.2. To investigate the risk factors related with mortality for Pseudomonas aeruginosa septicemia.Methods:1. The date of 89 cases of Pseudomonas aeruginosa septicemia from Jan 2004 to May 2009 in Nanfang Hospital were collected.2. The date of the included cases were studied retrospectively. The clinical characteristics of initial septicemia, including:time of intial blood culture, age, gender, hospital department, hospital infection type, duration of hospital stay before septicemia, length of hospitalization, stay-in-ICU, comorbid illness, invasive procedure, immunosuppressive therapy, laboratory findings, source of septicemia, results of initial blood culture, antibiotic treatments during the 15 days prior to septicemia, and outcome were recorded.3. Pseudomonas aeruginosa from blood cultures in patients was isolated by PHOEN IX 100 automation system. Antibiotic susceptibility test was performed by K-B disk diffusion method. Pseudomonas aeruginosa was confirmed by using standard of National Commitee for Clinical Laboratory Standards into sensitive, resistant, and intermediate.4. Prognostic index:the 30-day mortality and survival time.5. All the data were analyzed by SPSS software 13.0 version. The drug resistance status of Pseudomonas aeruginosa was analyzed withχ2 test(Pearson Chi-Square or Fisher’s Exact Test). The prognostic factors of univariate analysis:The measurement data was analyzed with t test(equal variances assumed), or Satterthwaite estimation t test(equal variances not assumed). The enumeration data was analyzed withχ2 test(Pearson Chi-Square or Fisher’s Exact Test). On the basis of univariate analysis, the variables P<0.05 were analyzed with binary Logistic regression analysis, identifing the independent risk factors of mortality for Pseudomonas aeruginosa septicemia. The survival time was analyzed with Kaplan-Meier method. P<0.05 is a statistically significant difference.Results:1.89 patients with Pseudomonas aeruginosa septicemia were included in this retrospective study.14 patients belong to community infection, and 75 patients belong to hospital infection.52 patients were male, and 37 patients were female.42 patients were in hematology specialty,10 patients were in pediatric ward,8 patients were in nephrology department,6 patients were in division of respiratory disease.23 patients were in other wards.2. The resistant rates of Pseudomonas aeruginosa strains to 10 common usable antibiotics were less than 30%. Meropenem has the lowest resistant rate 6.82%, followed by cefoperazone/sulbactam 8.64%. The resistant rates to amikacin, cefepime, piperacillin/tazobactam, ceftazidime, imipenem, ciprofloxacin, levoflozacin were 10.11%,11.11%,12.79%,13.95%,15.91%,17.07%,20.00% respectively. Aztreonam has the highest resistant rate 26.79%. The multidrug resistance rate of Pseudomonas aeruginosa strains was 16.85%, and pan-drug resistance rate of Pseudomonas aeruginosa strains was 3.37%.3. The resistant rates of imipenem-resistant Pseudomonas aeruginosa strains to ceftazidime (P=0.000), cefepime (P=0.000), cefoperazone/sulbactam (P=0.001), piperacillin/tazobactam (P=0.000), ciprofloxacin (P=0.000), levoflozacin (P=0.000), amikacin (P=0.001), meropenem (P=0.000) were more than that of the imipenem-susceptible strains, while remarkable differences (P<0.05). 4. The resistant rates of meropenem-resistant Pseudomonas aeruginosa strains to ceftazidime (P=0.003), cefepime (P=0.000), cefoperazone/sulbactam (P=0.000), piperacillin/tazobactam (P=0.000), ciprofloxacin (P=0.000), levoflozacin (P=0.000), amikacin(P=0.001), imipenem (P=0.000) were more than that of meropenem-susceptible strains, while remarkable differences (P<0.05).5. The resistant rates of meropenem-resistant Pseudomonas aeruginosa strains (P=0.000) or imipenem-resistant Pseudomonas aeruginosa strains (P=0.000) to multidrug resistance were more than that of the sensitive strains, while remarkable differences (P<0.05).6. The resistant rates of Pseudomonas aeruginosa strains isolated from community infection patients between hospital infection patients to 10 common usable antibiotics were not statistically significant differences, P>0.05. Same were for different gender patients.7. The resistant rates of Pseudomonas aeruginosa strains isolated from hematology specialty ward to ceftazidime (χ2=4.993, P=0.025), cefepime (P=0.032), cefoperazone/sulbactam (P=0.012), aztreonam(χ2=8.984, P=0.003), ciprofloxacin (χ2=7.495, P=0.006) were less than that of strains isolated from other wards, while remarkable differences (P<0.05). But no differences were to piperacillin/tazobactam(χ2=1.877, P=0.171), levoflozacin(χ2=3.013, P=0.083), amikacin(P=0.163), imipenem (χ2=0.158, P=0.691), meropenem(P=0.205), P>0.05.8. The resistant rates of Pseudomonas aeruginosa strains isolated from the patients using carbapenem antibiotics to ceftazidime (P=0.000), cefepime (P=0.003), cefoperazone/sulbactam (P=0.032), piperacillin/tazobactam (P=0.012), aztreonam (P=0.008), ciprofloxacin (P=0.015), levoflozacin (P=0.005), imipenem (P=0.000), meropenem (P=0.018) were more than that of strains isolated from the patients not using carbapenem, while remarkable differences (P<0.05). 9. The resistant rates of Pseudomonas aeruginosa strains isolated from the patients using two or more antibiotics were more than that of strains isolated from the patients using one antibiotics or not.10.65 patients survived within 30 days, and 24 patienst died.30-day mortality was 27%.11. The univariate analysis results:the factors associated with the higher 30-day mortality were Pitt Bacteremia Score(χ2=-9.050,P=0.000), plasma albumin(χ2=3.030,P=0.003), indwelling central venous catheter(χ2=4.113,P=0.043), imipenem-resistant Pseudomonas aeruginosa(P=0.000), meropenem-resistant Pseudomonas aeruginosa(P=0.005), multidrug resistance Pseudomonas aeruginosa(P=0.000), inappropriate empiric antibiotic therapy(χ2=28.578,P=0.000), empiric antibiotic therapy(χ2=6.493,P=0.019), the differences were statistically significant, P<0.05. Empiric monotherapy with inappropriate antibiotic therapy of 36.2%, empiric combination antibiotic therapy with inappropriate antibiotic therapy of 14.3%, the difference of proportion was statistically significant,χ2=5.543,P=0.019.12. Binary Logistic regression analysis identified two independent risk factors of mortality:Pitt Bacteremia Score(P=0.000, OR=4.313) and inappropriate empiric antibiotic therapy(P=0.001, OR=29.471).13. Compared to monotherapy, there was a trend to increase survival time for neutropenic patients receiving empiric combination antibiotic therapy, but the difference was not statistically significant(χ2=0.847,P=0.358). Compared to monotherapy, for neutropenic patients receiving definite combination antibiotic therapy, the difference between survival time was not statistically significant(χ2=0.036,P=0.849).14. Compared to monotherapy, for non-neutropenic patients receiving empiric combination antibiotic therapy, the survival time were longer and survival rate was higher, the difference was statistically significant(χ2=4.186,P=0.041). Compared to monotherapy, for non-neutropenic patients receiving definite combination antibiotic therapy, the difference between survival time was not statistically significant(χ2=0.348,P=0.555).Conclusions:1. The resistant rates of Pseudomonas aeruginosa strains to 10 common usable antibiotics were less than 30%. Meropenem has the lowest resistant rate, followed by cefoperazone/sulbactam. Aztreonam has the highest resistant rate.2. The resistant rates of imipenem-resistant Pseudomonas aeruginosa strains or meropenem-resistant Pseudomonas aeruginosa strains to common usable antibiotics were more than that of the sensitive strains. Same were multidrug resistance strains.3. Using carbapenem antibiotics and using two or more antibiotics and aggravate resistance rates of Pseudomonas aeruginosa strains.4. High Pitt Bacteremia Score and inappropriate empiric antibiotic therapy were independent mortality risk factors for Pseudomonas aeruginosa septicemia.5. Empiric combination antibiotic therapy can reduce the frequency of inappropriate antibiotic therapy.6. Compared to monotherapy, for non-neutropenic patients receiving empiric combination antibiotic therapy, the mortality was lower, and the survival time was longer.更多还原