难治性下呼吸道感染患者BALF病原菌分布及药敏分析

目的：探讨新疆自治区人民医院难治性下呼吸道感染患者支气管镜肺泡灌洗液( BALF)病原菌分布及其药敏状况,为临床合理用药提供依据。方法收集2013年6月到2015年5月难治性下呼吸道感染中BALF标本,对分离培养结果及药敏实验结果进行回顾性分析;结果难治性下呼吸道感染肺泡灌洗阳性患者255例,共培养出287株病原菌,革兰阳性菌占26．5%,革兰阴性菌占70．7%,真菌占2．8%,革兰阴性菌中排列于前4位的主要菌种依次是肺炎克雷伯菌、铜绿假单胞菌、大肠埃希菌、鲍曼不动杆菌,其中鲍曼不动杆菌普遍耐药程度最高,对亚胺培南和美罗培南耐药率较高,分别为68%、64%,对米诺环素及阿米卡星最为敏感;革兰阳性菌主要为金黄色葡萄球菌41株。未见万古霉素耐药菌株。结论难治性下呼吸道感染患者肺泡灌洗液主要以革兰阴性杆菌为主,各种病原菌对抗菌药物的敏感度各不相同,差异较大,加强病原菌耐药性检测有助于治疗方案的制定或调整,及早控制感染。     

继发性血流感染108例病原学特点分析

目的 研究感染来源明确的血流感染患者的病原学特点. 方法 收集四川省人民医院2011年1月—2013年6月实验室确诊、感染来源明确的血流感染患者临床资料,回顾性分析其病原学特点. 结果 共计108例诊断为有明确感染来源的血流感染患者纳入研究,其中93例为单一菌感染,15例为复数菌感染. 常见的感染来源为泌尿系统、腹腔和呼吸道. 泌尿系统和腹腔来源血流感染患者中,大肠埃希菌分别占75.8%和42.4%;下呼吸道来源血流感染者中,鲍曼不动杆菌占62.5%,且对碳青霉烯类抗生素耐药率为100%. 108例30 d死亡21例(19.4%),其中泌尿系统来源血流感染者病死率最低(3.0%),而下呼吸道来源血流感染者病死率最高(45.8%),非发酵革兰阴性杆菌和真菌血流感染患者的病死率分别为55.0%和50.0%. 结论 不同感染来源的血流感染患者病原菌分布差异较大,抗生素治疗应密切结合感染来源、菌种及细菌耐药情况.     

耐亚胺培南鲍曼不动杆菌的体外联合药物敏感试验

目的 了解体外联合药物敏感试验对耐亚胺培南鲍曼不动杆菌的效果,为临床抗感染治疗提供依据.方法 收集自2007年3月至2008年2月耐亚胺培南鲍曼不动杆菌27株标本,以E test法和琼脂稀释法测定7种常用抗菌药物的最低抑菌浓度(MIC),以肉汤稀释棋盘法进行联合药物敏感试验,用时间杀菌试验检测米诺环素和头孢哌酮-舒巴坦的协同率.结果 肉汤稀释棋盘法结果提示,米诺环素与头孢哌酮-舒巴坦、阿米卡星、环丙沙星的协同率分别为74.1%、28.0%、48.1%,阿米卡星与头孢哌酮-舒巴坦、环丙沙星的协同率分别为23.1%、37.0%,头孢哌酮-舒巴坦与环丙沙星的协同率为7.1%.米诺环素与头孢哌酮-舒巴坦联合后药物浓度均降至非耐药范围内.时间杀菌试验结果提示,米诺环素和头孢哌酮-舒巴坦的协同率为100%.结论 针对临床上多重耐药鲍曼不动杆菌的感染,推荐使用米诺环素加头孢哌酮-舒巴坦进行联合治疗.     

224例鲍曼不动杆菌感染的临床特征及耐药性分析

目的了解我院224例鲍曼不动杆菌感染的临床特征及耐药性。方法采用常规方法进行细菌培养、菌株鉴定及药敏检测。结果 201名患者共分离出224株鲍曼不动杆菌,患者主要集中在ICU(33.8%)、外科(25.9%)、呼吸内科(14.4%)、骨科(6.1%),基础疾病以呼吸系统疾病(64.2%)、心血管系统疾病(30.8%)、神经系统疾病(29.8%)及糖尿病(22.9%)多见,与手术治疗及有创检查治疗(56.7%)、联合使用≥2种抗生素(80.6%)及使用时间≥15天(38.8%)可能存在相关性。224株鲍曼不动杆菌对米诺环素敏感性最高(66.1%),对美罗培南、氨苄西林/舒巴坦、头孢哌酮/舒巴坦敏感性超过55%。结论鲍曼不动杆菌感染与患者有基础疾病、有创性检查治疗及使用广谱抗生素及时间过长有关,其耐药情况严重,多重耐药及泛耐药菌株日益增多,目前对米诺环素、舒巴坦、碳青酶烯类抗生素仍保持相对敏感性,临床应根据药敏结果合理选择使用抗生素。     

Healthcare-associated infections in rheumatology in Japan

Prospective observational study was performed to elucidate the incidence and characteristics of healthcare-associated infections in a university hospital for rheumatology care. In this study, a total of 1,226 patients were prospectively enrolled between March 2004 and February 2006 and between April 2008 and December 2008. Healthcare-associated infection was defined as an infection developing after the third day of admission to the rheumatology ward. We detected the following 54 healthcare-associated infections in 49 patients: respiratory tract infection, 14 cases; Clostridium difficile infection, 2 cases; urinary tract infection, 4 cases; bloodstream infection, 9 cases; skin infection, 2 cases; reactivation of latent cytomegalovirus infection, 6 cases; herpes zoster infection, 5 cases; Candida infection, 7 cases; others, 4 cases. The incidence rate of respiratory tract infection was the highest. Methicillin-resistant Staphylococcus aureus was the causative bacterium in 21% of respiratory tract infections cases. Bloodstream infection due to the insertion of a catheter and opportunistic infection by a latent virus were also occurred commonly. Respiratory tract infection, bloodstream infection and opportunistic infection by a latent virus were the most common causes of healthcare-associated infection in rheumatology. It is important to pay more attention to healthcare-associated infection.     

血培养中碳青霉烯类耐药鲍曼不动杆菌感染特征及耐药基因分析

目的 分析我院2018—2020年临床血培养检出的碳青霉烯类耐药鲍曼不动杆菌(carbapenem-resistant Acinetobacter Baumannii, CRAB)的感染特征及耐药基因分布情况,为防止院内感染、临床抗菌药物的合理使用及临床早期经验性提供依据。方法 收集2018年1月至2020年12月临床分离的血培养鲍曼不动杆菌48株,应用Logistic回归分析血流感染CRAB的可能危险因素。采用VITEK2 Compact全自动微生物分析系统进行细菌鉴定及药敏试验,热裂解法提取DNA,并应用PCR的方法检测常见鲍曼不动杆菌的碳青霉烯类耐药基因(OXA-23、OXA-51、NDM-1)及插入序列ISAba-1、整合酶Int I基因。结果 在所有XDR-AB中重症医学科的检出率最高,占68.4%。Logistic回归分析结果显示,肺炎、恶性肿瘤、静脉穿刺置管、输血、气管插管、尿管插管、胃管插管及支气管镜检查与血流感染CRAB有关(P<0.05),且肺炎(OR=81.894)是血流感染CRAB的独立危险因素(χ²=4.689,P<0.05)。多重耐药菌(13株)和广泛耐药菌(19株)均携带有OXA-23与OXA-51基因。敏感菌株中OXA-51基因检出率为43.8%,没有检测出OXA-23基因。48株菌株均没有检测出NDM-1基因。耐药基因OXA-23、OXA-51、ISAba-1的检出率在耐药菌和敏感菌之间差异有统计学意义(χOXA-232=48.000,χOXA-512=13.066,χISAba-12=15.709,均P<0.05)。结论 肺炎为我院血流感染CRAB的独立危险因素,非恶性肿瘤的患者感染CRAB的风险是有恶性肿瘤患者的21倍。本院碳青霉烯类耐药鲍曼不动杆菌主要为OXA-23型与OXA-51型菌株,且携带有OXA-23耐药基因的鲍曼不动杆菌对碳青霉烯类药物耐药率为100%,未携带该耐药基因的鲍曼不动杆菌对该类药物均呈敏感,提示OXA-23基因可能是造成CRAB耐药的原因,临床应加强院感管理,合理使用抗菌药物,防止该类鲍曼不动杆菌的暴发传播。     

Genotypic analysis of Acinetobacter bloodstream infection isolates in a Turkish university hospital

Acinetobacter baumannii is a significant pathogen of bloodstream infections in hospital patients that frequently causes single clone outbreaks. We aimed to evaluate the genetic relatedness and antimicrobial susceptibility of Acinetobacter spp. bloodstream isolates, in order to obtain insight into their cross-transmission. This prospective study was conducted at the Erciyes University Hospital. During a 1-y period, all patients with nosocomial BSI caused by Acinetobacter spp. were included in the study. All data with regard to the patients, underlying diseases and risk factors for BSI and the severity of disease were collected. Blood culture isolates of Acinetobacter spp. were identified according to their morphology and biochemical reactions. The antimicrobial susceptibility was determined using the Kirby-Bauer disk diffusion test according to the NCCLS; the genetic relatedness of isolates was determined by RAPD-PCR analysis and pulsed-field gel electrophoresis (PFGE). 41 patients acquired a nosocomial bloodstream infection caused by A. baumanii during this period. 88% of these infections (36 of 41) occurred while the patients were treated in the intensive care unit. Nearly 80% of the isolates belonged to 3 genotypes, suggesting cross-transmission in ICU settings where infection control practices are poor. All Acinetobacter isolates were multidrug-resistant and the crude mortality of patients infected with A. baumanii was 80.5%. We concluded that the genetic relatedness of Acinetobacter spp. causing BSI was very high, indicating cross-transmission within the ICU setting. Essential components of an infection control programme to prevent nosocomial transmission of A. baumannii are early detection of colonized patients, followed by strict attention to standard precautions and contact isolation.     

我院近3年下呼吸道革兰阴性杆菌耐药性监测

目的 调查我院近3年下呼吸道革兰阴性杆菌的耐药情况.方法 使用MIC法对我院下呼吸道感染住院患者的痰液标本中临床分离的926株革兰阴性杆菌进行药敏试验,并用WHONET 5.4软件进行数据分析.结果 926株革兰阴性杆菌中最常见的菌种依次为大肠埃希菌(29.7%)、肺炎克雷伯菌(23.7%)、铜绿假单胞菌(14.3%)、鲍曼不动杆菌(12.1%).大肠埃希菌、肺炎克雷伯菌对多黏菌素B、亚胺培南、美罗培南和咪诺环素保持高度敏感,耐药菌率在10%以内,对阿米卡星、哌拉西林/三唑巴坦、头孢哌酮/舒巴坦、头孢他啶及头孢匹肟的耐药率为30%以内,对其余所检测药物的耐药率均在30%以上.铜绿假单胞菌对多黏菌素B和咪诺环素;而亚胺培南,美罗培南、哌拉西林/三唑巴坦,头孢哌酮/舒巴坦和阿米卡星耐药率低于30%{鲍曼不动杆菌耐药情况比较严重,只有多黏菌素B、头孢哌酮/舒巴坦高度敏感,耐药率在10%以内,对亚胺培南和美罗培南的耐药率在20%以内,对其余所检测药物的耐药率均在30%到60%以上.结论 本研究结果对我院革兰阴性杆菌感染的经验用药治疗有重要参考价值.     

Enterococcal bacteraemia: epidemiological, microbiological, clinical and prognostic characteristics, and the impact of high level gentamicin resistance

Enterococci are increasingly common nosocomial pathogens that can cause serious infections and often acquire antibiotic resistance. This study focused on the epidemiological, microbiological and clinical characteristics of enterococcal bacteraemia with special attention to the impact of high level gentamicin resistance (HLGR) on prognosis. 117 cases of enterococcal bacteraemia constituted 8% of all bacteraemic episodes during the y 2002. The most common source of infection was the urinary tract, more than half of the episodes were polymicrobial and the vast majority of cases was healthcare-associated. 50 of 117 isolates (43%) were resistant to gentamicin. Infection-related mortality (22 of 117, 19%) was associated with 2 independent variables in multivariate analysis: severity-of-illness score (OR=39.6, p<0.00001) and HLGR (OR=6.4, p=0.006). It was concluded that HLGR adversely affects the outcome of bacteraemic enterococcal infection.     

Risk factors for nosocomial imipenem-resistant Acinetobacter baumannii infections.

OBJECTIVES: To identify the risk factors for nosocomial imipenem-resistant Acinetobacter baumannii (IRAB) infections. METHODS: A prospective case-control study, set in an 1100-bed referral and tertiary-care hospital, of all patients who had nosocomial A. baumannii infections between January 1 and December 31, 2004. Only the first isolation of A. baumannii was considered. RESULTS: IRAB was isolated from 66 (53.7%) patients and imipenem-sensitive Acinetobacter baumannii (ISAB) was isolated from 57 (46.3%) patients during the study period. The mean duration of hospital stay until A. baumannii isolation was 20.8+/-13.6 days in IRAB infections, whereas it was 15.4+/-9.4 days in ISAB infections. Of the patients, 65.2% with IRAB infections and 40.4% with ISAB infections were followed at the intensive care unit (ICU). Previous carbapenem use was present in 43.9% of the patients with IRAB and 12.3% of the patients with ISAB infection. In univariate analysis female sex, longer duration of hospital stay until infection, ICU stay, emergent surgical operation, total parenteral nutrition, having a central venous catheter, endotracheal tube, urinary catheter or nasogastric tube, previous antibiotic use, and previous administration of carbapenems were significant risk factors for IRAB infections (p<0.05). In multivariate analysis, longer duration of hospital stay until A. baumannii isolation (odds ratio (OR) 1.043; 95% confidence interval (CI) 1.003-1.084; p=0.032), previous antibiotic use (OR 5.051; 95% CI 1.004-25.396; p=0.049), and ICU stay (OR 3.100; 95% CI 1.398-6.873; p=0.005) were independently associated with imipenem resistance. CONCLUSIONS: Our results suggest that the nosocomial occurrence of IRAB is strongly related to an ICU stay and duration of hospital stay, and that IRAB occurrence may be favored by the selection pressure of previously used antibiotics.     

Citywide clonal outbreak of multiresistant Acinetobacter baumannii and Pseudomonas aeruginosa in Brooklyn,NY: the preantibiotic era has returned

BACKGROUND: Carbapenems are important agents for treating nosocomial gram-negative infections. Carbapenem-resistant bacteria have become increasingly problematic in certain regions. This study determined the citywide prevalence and molecular epidemiological features of carbapenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa in Brooklyn, NY. METHODS: All unique patient isolates of A baumannii and P aeruginosa were collected from 15 Brooklyn hospitals from July 1, 1999, through September 30, 1999. Antibiotic susceptibilities, the genetic relatedness of resistant isolates, and the relationship between antibiotic use and resistance rates were determined. RESULTS: A total of 419 isolates of A baumannii and 823 isolates of P aeruginosa were collected. For A baumannii, 53% were resistant to meropenem and/or imipenem, and 12% were resistant to all standard antibiotics. Ribotyping revealed that a single clone accounted for 62% of the samples and was isolated from patients at all 15 hospitals. The rate of carbapenem resistance was associated with cephalosporin use at each hospital (P =.004). For P aeruginosa, 24% were resistant to imipenem, 5% to amikacin, and 15% to 29% to other antipseudomonal agents. Ribotyping revealed that 3 clones accounted for nearly half of the isolates and were shared by most hospitals. CONCLUSIONS: Approximately 400 patients were infected or colonized with carbapenem-resistant A baumannii and P aeruginosa during a 3-month period in 1999. A few strains have spread widely throughout hospitals in this region. The prevalence of resistant A baumannii seems to be correlated with cephalosporin use. Multiresistant hospital-acquired bacteria should be viewed as a serious public health issue rather than an individual hospital's problem. An intensive coordinated effort will be needed to effectively address this problem.     

Antibiotic resistance of Helicobacter pylori isolated from Korean patients]

The distribution of minimal inhibitory concentrations (MIC) for amoxicillin, clarithromycin, metronidazole, tetracycline, azithromycin, and fluoroquinolone (ciprofloxacin, levofloxacin, and moxifloxacin) have shifted to higher concentrations from 1987 to 2003 in Helicobacter pylori (H. pylori) strains isolated from Korean patients. MIC values of secondary isolates were higher than those of primary isolates. Of treatment-failure patients, 16.4% showed mixed infections with both antibiotic-susceptible and -resistant H. pylori strains. A total of 89.6% of patients with treatment failure and 52.3% of patients without antibiotic treatment had H. pylori strains resistant to two or more antimicrobial agents (multi-drug resistance, MDR). The most common antibiotics showing MDR were clarithromycin, metronidazole, and azithromycin. The resistance rates to both amoxicillin and clarithromycin were 34.3% in secondary isolates and 6.2% in primary isolates. The resistance rates to both clarithromycin and metronidazole were 73.1% in secondary isolates and 7.7% in primary isolates. In addition, there was a significant difference in antibiotic resistance between two institutions located at Seoul and Gyeonggi provinces. To provide adequate informations about susceptible antibiotics to clinicians, continuous surveillance of antibiotic susceptibilities is needed in Korea.     

获得性肺炎患者血流感染病原菌分布及耐药性分析

目的分析获得性肺炎患者血流感染病原菌分布及耐药性。 方法选取2017年3月至2021年7月北京积水潭医院收治的305例医院获得性肺炎患者为对象,采集年龄、性别、住院时间、合并基础疾病、气管插管例数、原发感染灶、血培养及药敏试验结果。 结果305例获得性肺炎患者中并发血流感染174例(57.05%),分离出186株病原菌,其中G^－ 137株(73.66%),G^－中肺炎克雷伯菌32例(17.20%),鲍曼不动杆菌29例(15.59%)、铜绿假单胞菌24例(12.90%);G⁺ 46株(24.73%),其中金黄色葡萄球菌19例(10.22%);真菌3株(1.61%)。肺炎克雷伯菌对头孢曲松、氨苄西林耐药性高,对氨曲南、妥布霉素耐药性低;鲍曼不动杆菌对头孢曲松、呋喃妥因耐药性高,对氨曲南、庆大霉素耐药性低;铜绿假单胞菌对氨苄西林、呋喃妥因耐药性高,对丁胺卡那霉素、复方新诺明、氨曲南耐药性低。金黄色葡萄球菌对青霉素G、红霉素耐药性高,对万古霉素、替考拉宁耐药性低;肺炎链球菌对青霉素G、红霉素、庆大霉素耐药性高,对万古霉素、替考拉宁耐药性低。 结论获得性肺炎患者血流感染病原菌分布以G^－多见,其中肺炎克雷伯菌、鲍曼不动杆菌感染常见,对氨苄西林、呋喃妥因及头孢耐药性高;G⁺感染中金黄色葡萄球菌常见,对阿奇霉素、红霉素、青霉素耐药性高。     

Healthcare-associated infections in neonates

PURPOSE OF REVIEW: To identify important findings in the recent literature related to healthcare-associated infections in neonatal care. RECENT FINDINGS: Bloodstream infection remains the leading healthcare-associated infection in the neonatal unit, but multimodal interventions have been shown to successfully reduce this life-threatening complication. Emerging pathogens such as methicillin-resistant Staphylococcus aureus, extended-spectrum-beta-lactamase-producing Gram-negative organisms and pan-resistant Acinetobacter baumannii or Serratia marcescens complicate the use of standard antibiotic treatment and are a particular concern in this setting because of the limitation in antibiotic classes among neonates. Community-acquired methicillin-resistant S. aureus infections are increasing in frequency and are particularly worrisome. Fluconazole prophylaxis offers a simple solution for the prevention of invasive Candida infection and has been already widely adopted. Although there is evidence for its efficacy, there is still some debate about the pros and cons of azole prophylaxis in the prevention of invasive Candida infections. Furthermore, its use in low-prevalence settings remains highly questionable. The introduction of restrictive guidelines limiting the use of antibiotics in early-onset neonatal infections has proved to be safe and efficient and may also reduce the incidence of late-onset infection. Outbreaks remain an ongoing concern in neonatal care and are increasingly complicated by emerging multiresistant pathogens. SUMMARY: Healthcare-associated infections remain a permanent challenge among neonates.     

Carbapenem-resistant Acinetobacter baumannii infections after organ transplantation

P. Reddy, T.R. Zembower, M.G. Ison, T.A. Baker, V. Stosor. Carbapenem-resistant Acinetobacter baumannii infections after organ transplantation.
Transpl Infect Dis 2010: 12: 87–93. All rights reserved
Abstract: Multi-drug resistant (MDR) gram-negative infections among solid organ transplant (SOT) recipients have long been associated with high morbidity and mortality. Acinetobacter baumannii has emerged as a potent nosocomial pathogen with the recent acquisition of resistance to broad-spectrum β-lactams, aminoglycosides, fluoroquinolones, and most notably, carbapenems. Despite a national rise in carbapenem-resistant A. baumannii (CRAB) infections, outcomes among SOT recipients with this emerging MDR pathogen are largely unknown. This single-center cohort is the first to describe the characteristics, complications, and outcomes among abdominal organ transplant recipients with CRAB. The current study suggests that SOT patients with CRAB suffer from prolonged hospitalization, infection with other MDR organisms, allograft dysfunction and loss, and high overall infection-related mortality.     

耐亚胺培南鲍曼不动杆菌耐药性分析

目的了解64株临床分离的耐亚胺培南鲍曼不动杆菌对18种常用抗生素的耐药性。方法采用Micro Scanwalk Away-40微生物分析仪进行菌株鉴定和药敏试验,头孢哌酮/舒巴坦及米诺环素药敏试验采用K-B法。结果亚胺培南耐药的鲍曼不动杆菌对头孢哌酮/舒巴坦的耐药率最低为37.5%,其次为米诺环素54.7%,对头孢噻肟、头孢曲松、哌拉西林、哌拉西林/他唑巴坦的耐药率最高为100.0%,其余抗菌药物的耐药率均大于81.1%。结论亚胺培南耐药的鲍曼不动杆菌多重耐药严重,部分为泛耐药菌株,仅对头孢哌酮/舒巴坦较为敏感。     

深圳市腹泻患者沙门菌感染状况和耐药性分析

目的 分析2014-2017年深圳地区腹泻患者沙门菌的感染特征和耐药性情况,为沙门菌感染的防控提供科学依据。方法 从深圳市3家哨点医院腹泻门诊收集患者粪便标本,进行沙门菌的分离鉴定、血清分型及药敏试验;对7家医院上送的住院病人分离的沙门菌进行血清分型和药敏试验。结果 4 847份门诊患者的粪便标本中,分离出192株沙门菌,检出率为4.0%。5-10月是沙门菌检出的高峰, 5岁以下儿童和6-17岁是感染的主要人群,检出率分别为6.2%和5.3%。192株沙门菌中鉴定出18种血清型,其中鼠伤寒沙门氏菌、鼠伤寒沙门氏菌变种和肠炎沙门氏菌是最常见的3种血清型,另有19株未能分型。77株住院病人分离的沙门菌中鉴定出20种血清型,其中肠炎沙门氏菌、鼠伤寒沙门氏菌变种、甲型副伤寒沙门氏菌占比分别为33.8%、13.0%和11.7%,另有3株未能分型。45株沙门菌对氨苄西林、环丙沙星和左旋氧氟沙星的耐药最为严重,自2015年开始出现对喹诺酮类药物的耐药和多重耐药菌株,10株鼠伤寒沙门氏菌中多重耐药率为50.0%。结论 深圳市腹泻患者的沙门菌感染以17岁以下儿童为主,5-10月份为感染的高峰期,沙门菌的血清型分散,其中肠炎沙门氏菌和鼠伤寒沙门氏菌、鼠伤寒沙门氏菌变种是主要的血清型,多重耐药自2015年开始日趋严重,临床上应合理规范用药并且加强耐药监测。     

Nosocomial bloodstream infections caused by Acinetobacter species in United States hospitals: clinical features, molecular epidemiology, and antimicrobial susceptibility.

We examined the clinical and epidemiological features of nosocomial bloodstream infections (BSIs) caused by Acinetobacter species and observed from 1 March 1995 through 28 February 1998 at 49 United States hospitals (SCOPE National Surveillance Program). Acinetobacter species were found in 24 hospitals (49%) and accounted for 1.5% of all nosocomial BSIs reported. One hundred twenty-nine isolates were identified either as A. baumannii (n=111) or other Acinetobacter species (n=18). Patients with A. baumannii BSI, compared with patients with nosocomial BSI caused by other gram-negative pathogens, were more frequently observed in the intensive care unit (69% vs. 47%, respectively; P<.001; odds ratio [OR] 2.4; 95% confidence interval [CI] 1.6-3.7) and were more frequently receiving mechanical ventilation (58% vs. 30%, respectively; P<.001; OR 3.2; 95% CI 2.1-4.8). Crude mortality in patients with A. baumannii BSI was 32%. Molecular relatedness of strains was studied by use of polymerase chain reaction-based fingerprinting. Clonal spread of a single strain occurred in 5 hospitals. Interhospital spread of epidemic A. baumannii strains was not observed. The most active antimicrobial agents against A. baumannii (90% minimum inhibitory concentration values) were imipenem (1 mg/L; 100% of isolates susceptible), amikacin (8 mg/L; 96%), tobramycin (4 mg/L; 92%), and doxycycline (4 mg/L; 91%). Thirty percent of isolates were resistant to > or =4 classes of antimicrobials and were considered to be multidrug resistant.     

Clinical Infections and Bloodstream Isolates Associated with Fever in Patients Undergoing Chemotherapy for Acute Myeloid Leukemia

Summary Background: Patients with acute myeloid leukemia (AML) are at high risk for infections. The aim of this study was to identify the sources of fever and the type of pathogens that cause bloodstream infection in patients with AML undergoing cytotoxic chemotherapy and antibiotic prophylaxis. Patients and Methods: The source of fever and the type of pathogens causing bloodstream infection were identified for 129 febrile episodes experienced by 42 patients with AML receiving cytotoxic chemotherapy and antibiotic prophylaxis. Results: A source of fever was identified in 81% of all febrile episodes. Mucositis (21.7%), pneumonia (13.2%), central venous catheter infection (12.4%), neutrophenic enterocolitis (9.3%) and invasive fungal disease (9.3%) were the most common sources of fever. Of 16 central venous catheter infections, seven (43.8%) were not associated with local signs. 49 febrile episodes (37.9%) were associated with bloodstream infections, of which 14 (28.6%) were polymicrobic and seven (14.3%) had an undefined source of infection. Bloodstream infection was commonly associated with cellulitis (60%), mucositis (57.1%), central venous catheter infection (55.6%), neutropenic enterocolitis (41.7%) and invasive fungal disease (41.7%). Gram-positive microorganisms were the most common blood isolates (75.8%). Gram-negative bacteremic infections occurred in eight episodes (12.1%) experienced by patients who were nor receiving ciprofloxacin prophylaxes at the time of bacteremia. Noninfectious sources of fever accounted for 23 (17.8%) of the 129 febrile episodes. Conclusion: Although the spectrum of pathogens that cause infection in this group of patients has shifted from gram-negative to gram-positive bacteria, the most common sources of infection remain the same as previously described and they mainly involve integumental surfaces. Received: December 5, 1999 · Revision accepted: August 8, 2000