A pseudo-outbreak of Pseudomonas on a special care baby unit

Following isolation of a multi-antibiotic-resistant pseudomonad from a newborn infant on admission to the Special Care Baby Unit and further isolation of apparently the same organism from two additional infants, a full investigation was instigated in an attempt to discover the source of the organism. This revealed a further 13 infants apparently colonized with the same organism. Repeated screening of the infants with a commercial sterile swab/transport medium failed to isolate the organism. Examination of bottles of the in-house transport medium, which had been stored under a sink, produced further isolates of the same organism. Water splashed from the sink was suspected as the ultimate source of contamination. Biochemical characterization showed that P. pickettii and at least one other Pseudomonas species were involved. The epidemiological, clinical and economic implications of the 'outbreak' are discussed together with the ultimate financial implications for investigation of such incidents.     

Risk factors for and impact of infection or colonization with aztreonam-resistant Pseudomonas aeruginosa.

OBJECTIVE: To identify risk factors for infection or colonization with aztreonam-resistant Pseudomonas aeruginosa and examine the impact of this organism on mortality. DESIGN: A case-control study was performed to identify risk factors for infection or colonization with aztreonam-resistant P. aeruginosa. A cohort study was subsequently performed to examine the impact of aztreonam resistance on outcomes. SETTING: A tertiary referral center in southeastern Pennsylvania.Participants. Inpatients with a clinical culture positive for P. aeruginosa between January 1, 1999, and December 31, 2000. RESULTS: Of 720 P. aeruginosa. isolates, 183 (25.4%) were aztreonam-resistant and 537 (74.6%) were aztreonam susceptible. In a multivariable model, prior fluoroquinolone use (adjusted odds ratio [aOR], 1.81 [95% confidence interval {CI}, 1.17-2.80]), prior use of an antianaerobic agent (aOR, 1.56 [95% CI, 1.06-2.29]), and renal insufficiency (aOR, 1.59 [95% CI, 1.10-2.29]) were associated with infection or colonization with aztreonam-resistant P. aeruginosa, while older age (aOR, 0.98 [95% CI, 0.97-0.99] per year of age) was negatively associated with infection or colonization with this organism. In-hospital mortality was higher among subjects infected or colonized with aztreonam-resistant P. aeruginosa, compared with those who were infected or colonized with aztreonam-susceptible P. aeruginosa (25.7% vs 16.8%; P=.009), but in multivariable analysis, no significant association was found between infection or colonization with aztreonam-resistant P. aeruginosa and mortality. CONCLUSIONS: Curbing the use of fluoroquinolones and antimicrobials with antianaerobic activity may be an effective strategy to limit the emergence of aztreonam-resistant P. aeruginosa.     

Adhesive tapes in the special care baby unit

Semi-quantitative sampling of 37 taped sites and 37 matching control sites in 30 babies in a special care baby unit showed a tendency for bacterial growth under the cardiac monitors or the occlusive plastic adhesive tape to be greater than at the control site. This tendency was demonstrable even when potential pathogens were considered. During the study, an outbreak due to Candida albicans occurred. Antibiotic resistance of coagulase-negative staphylococci was marked and this, and other evidence, suggested that part of the skin flora was acquired from the unit.     

Investigation of an outbreak of infection with Acinetobacter calcoaceticus in a special care baby unit

During a period of 6 months, an 'epidemic strain' of Acinetobacter calcoaceticus was isolated from 10 pre-term neonates in a special care baby unit (scbu). Of these, nine had pulmonary infections. The tenth was found to have conjunctival colonization only. The 'epidemic strain' was characterized by serotyping, biotyping, bacteriocin typing and antibiograms. An identical strain was isolated from an 'Ambu' resuscitation device but not from other environmental samples or from staff on the unit. The outbreak ceased after the colonized resuscitator was removed and an appropriate disinfection policy implemented for the replacement resuscitators.     

某ICU耐亚胺培南铜绿假单胞菌感染现状调查

目的词查某院重症监护室（ICU）分离的铜绿假单胞菌耐亚胺培南药物的现状及治疗结果。方法以该ICU2004年全年经病原学证实的铜绿假单胞菌感染者为研究对象，药敏试验采用美国B-D全自动微生物检测系统完成，根据美国临床实验室标准化委员会标准判读结果。结果共检出57株菌，其中对亚胺培南敏感者33株（57．89％），耐药者24株（42．11％）。耐亚胺培南菌株中，耐药≥3类者占83．33％，显著高于亚胺培南敏感菌株的12．12％（X^2=28．906，P〈0．001）。57例患者，2例自动出院，47例治愈，3例病死（均为耐亚胺培南铜绿假单胞菌感染者）。结论ICU为耐亚胺培南铜绿假单胞菌感染高发病区，也是多重耐药菌株感染较多的病区，应重点监控。     

2例白内障人工晶体术后并发铜绿假单胞菌感染(眼内炎)调查

本院开展超声乳化白内障吸出联合人工晶体植入术4年来共做手术736例。2004年8月某日出现了2例手术后铜绿假单胞菌感染病例,我们针对这2例感染病例进行了医院交叉感染危险因素的调查,现报告如下。1临床资料1.1病例1女性,77岁,因双眼视力下降7年来我院就诊。查视力:右眼0.02,左眼0.2;双眼晶状体混浊,右眼晶状体核混浊Ⅲ级,左眼晶状体核混浊Ⅱ级,余检查阴性。以“双眼老年性白内障”行“右眼超声乳化白内障摘除联合人工晶体植入术”,术中后囊破裂,进行前部玻璃体切割及睫状沟内人工晶体植入,术后局部使用抗菌药物及激素类药物。术后第1 d视力为…     

Tap water colonization with Pseudomonas aeruginosa in a surgical intensive care unit (ICU) and relation to Pseudomonas infections of ICU patients.

Water faucets on a surgical intensive care ward were examined prospectively as a source of Pseudomonas aeruginosa infections. All water outlets harbored distinct genotypes of P aeruginosa over prolonged time periods. Over a period of 7 months, 5 (29%) of 17 patients were infected with P aeruginosa genotypes also detectable in tap water.     

综合医院铜绿假单胞菌的感染与耐药性

目的了解综合性医院铜绿假单胞菌(PAE)临床分布及对常用抗菌药物的耐药性,为临床医师合理选用抗菌药物提供依据。方法对2007年9月-2009年9月,医院分离的229株铜绿假单胞菌的基本特征及耐药性进行回顾性分析。结果铜绿假单胞菌的检出率为12.83%,居第2位;感染部位以下呼吸道感染最常见;检出的主要科室是呼吸科、重症监护病房;主要是老年及有基础疾病的患者;该菌对亚胺培南、左氧氟沙星、头孢哌酮/舒巴坦敏感性较好,耐药率分别为20.96%、17.90%、10.92%;对其他抗菌药物的耐药性均较高。结论应加强对铜绿假单胞菌感染率和耐药性的监测,以降低其感染发生率和耐药性。     

内科重症监护病房铜绿假单胞菌医院感染同源性及临床特点

目的研究内科重症监护病房(MICU)铜绿假单胞菌(PA)医院感染的同源性及临床特点,以指导临床预防PA传播,提高治疗效果。方法对某院2014年1—12月MICU发生医院感染的25例患者分离的55株PA进行脉冲场凝胶电泳(PFGE)同源性分析及聚类分析,对其临床特点、耐药性及其传播特点进行分析。结果共调查25例患者,平均年龄为(69.62±2.13)岁,平均住院时间(49.34±3.18)d;在分离出PA之前,84.00%的患者应用广谱抗菌药物2周,76.00%的患者入住过MICU,52.00%的患者使用呼吸机辅助通气。55株PA主要以A、F、H、K、N、V、W型为主要的流行菌株;感染A型、F型、H型及K型菌株的患者在各自住院时间上均存在交叉;有4例患者不同时期分离菌株的PFGE图谱分析显示不同菌型;PA对头孢他啶(72.73%)、哌拉西林/他唑巴坦(70.91%)、亚胺培南(70.91%)耐药率高,对阿米卡星耐药率最低(25.45%)。结论医疗机构应加强抗菌药物管理,加强医院感染控制措施,防止多重耐药和泛耐药细菌在医院内的播散。     

Emergence of nosocomial Pseudomonas aeruginosa colonization/infection in pregnant women with preterm premature rupture of membranes and in their neonates

The epidemiology, risk factors, maternal and neonatal outcomes of nosocomial Pseudomonas aeruginosa acquisition in preterm premature rupture of membranes were analysed. Of 63 women receiving antibiotic prophylaxis with co-amoxiclav, 11 acquired P. aeruginosa vaginal carriage with a median delay of 15 days (6-42) i.e. an incidence of 8.94 per 1000 days of expectant management. Five neonates born to 11 positive mothers were colonized or infected, three of whom died of fulminant sepsis. The duration of antibiotic treatment and multiple pregnancy were identified as independent risk factors. The epidemiological investigation revealed a vertical transmission between mothers and neonates, and suggested selective pressure of antibiotic treatment.     

某院铜绿假单胞菌的耐药变迁

以常用的10种抗生素：头孢他啶、庆大霉素、哌拉西林、环丙沙星、亚胺培南、阿米卡星、头孢噻肟、复方磺胺甲嗯唑、氯霉素、氨曲南对某院2001-2002年分离自住院患者标本的104株铜绿假单胞菌进行药敏试验。铜绿假单胞菌对哌拉西林、环丙沙星、阿米卡星、头孢噻肟的耐药率由2001年的38．46％、34．88％、34．88％、52．50％上升至2002年的62．30％、54．10％、45．90％、65．57％（均P〈0．05）；对庆大霉素的耐药率由2001年的81．40％下降至2002年的67．21％（P〈0．05）。     

医院感染铜绿假单胞菌耐药性分析

目的了解医院铜绿假单胞菌医院感染的分布及耐药性的变化趋势,指导临床合理使用抗菌药物。方法回顾性分析医院2007年1月-2009年12月临床分离出的219株铜绿假单胞菌的药敏结果进行统计分析。结果 219株铜绿假单胞菌主要分离自下呼吸道,其次是手术创面等部位;主要分布在ICU、呼吸内科、脑外科等科室,分别占34.2%、26.5%、21.5%;铜绿假单胞菌敏感率较高的抗菌药物是头孢哌酮/舒巴坦、美罗培南、亚胺培南,敏感率分别为98.2%、92.2%、91.8%;耐药率>50.0%的抗菌药物是庆大霉素、哌拉西林、妥布霉素,耐药率分别为87.2%、55.7%、52.5%。结论铜绿假单胞菌是医院感染的重要细菌,应加强对铜绿假单胞菌耐药性的监测,以减少多药耐药菌株的出现和医院感染的扩散。