High Rate of Oxacillin-Resistant Staphylococcus aureus Isolates in an Italian University Hospital

Summary

We reviewed our routine clinical laboratory records from January 1990 to March 1993 to evaluate the rate of oxacillin-resistance among nosocomial isolates of Staphylococcus aureus. Of 265 clinically significant isolates, 174 (65%) were oxacillin-resist S. aureus (ORSA). Most of these strains were obtained from surgery patients and/or were isolated from surgical wounds. The isolations of S. aureus increased during the study period: 45 in 1990, 50 in 1991, 130 in 1992 and 40 in the first trimester of 1993. The annual rates of ORSA among S. aureus isolated varied from 62 to 68% through these years.

Most ORSA isolates proved resistant to ciprofloxacin, gentamicin and rifampicin, and susceptible to vancomycin, netilmicin and cotrimoxazole. Based on these results, the need for a stringent application of infection control measures is outlined.     

Characteristics and Outcomes of Methicillin‐Resistant Staphylococcus aureus Bloodstream Infections in Patients with Cancer Treated with Vancomycin: 9‐Year Experience at a Comprehensive Cancer Center

Background.

Methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSIs) can cause significant morbidity and mortality in patients with cancer. However, data on outcomes of patients treated with vancomycin are lacking.

Methods.

We identified 223 patients with cancer who developed MRSA BSIs between January 2001 and June 2009 and were treated with vancomycin. Treatment failure was defined as death within 60 days of infection, persistent bacteremia ≥5 days, fever ≥4 days, recurrence or relapse, and secondary MRSA infection.

Results.

The treatment failure rate was 52% (116 of 223 patients). These patients were more likely to have been hospitalized, been treated with steroids within the previous 3 months, developed acute respiratory distress syndrome, required mechanical ventilation, required intensive care unit care, and community-onset infections (all p < .05). Risk factors for MRSA-associated mortality (27 of 223 patients; 12%) included hematologic malignancy and hematopoietic stem cell transplantation, community-onset infection, secondary BSI, MRSA with minimum inhibitory concentration (MIC) ≥2.0 μg/mL, mechanical ventilation, and a late switch to an alternative therapy (≥4 days after treatment failure; all p < .05). On multivariate analysis, mechanical ventilation and recent hospitalization were identified as independent predictors of vancomycin failure, and community-onset infection, secondary BSIs, and MIC ≥2 μg/mL were identified as significant predictors of MRSA-associated mortality.

Conclusions.

We found a high treatment failure rate for vancomycin in patients with cancer and MRSA BSIs, as well as a higher mortality. A vancomycin MIC ≥2 μg/mL was an independent predictor of MRSA-associated mortality. An early switch to an alternative therapy at the earliest sign of failure may improve outcome.     

肺炎多重耐药菌医院感染危险因素调查与分析

目的：探讨引起肺部发生多重耐药菌（ multidrug-resistant organism ,MDROs）与非MDROs院内感染的危险因素,为做好医院感染管理工作提供依据。方法收集2013年4月至10月广西7所三甲医院发生的MDROs及非MDROs肺炎患者共518例,根据病原菌耐药性分为MDROs组268例,非MDROs组250例,比较两组患者MDROs感染发生的危险因素差异。结果 MDROs引起的肺炎占医院内肺炎的51．74％,ICU是MDROs院内肺炎感染的高发科室,占66．07％;logistic 分析结果显示,血红蛋白含量、1个月内2类以上抗感染药物使用史是患者发生MDROs肺炎的独立危险因素（ P＜0．05）。结论积极预防和干预医院感染危险因素、合理使用现代诊疗技术和抗感染药物,有助于降低发生肺部MDROs和非MDROs院内感染的风险。     

Treatment of Post-Traumatic Hand Staphylococcus aureus Osteomyelitis with Oral Linezolid

Abstract

The Authors report on the use of linezolid for the treatment of three patients with osteomyelitis. All three patients had post-traumatic multisensitive hand bone methicillin-susceptible Staphylococcus aureus osteomyelitis, which did not respond to antimicrobial regimens including drugs in vitro active against the isolated strains. Clinical cure and microbiologic eradication was obtained with oral linezolid in all three patients. Linezolid was well tolerated. Mild thrombocytopenia was observed in one patient at the end of the third week of treatment and it was promptly resolved after the discontinuation of linezolid. Linezolid minimum inhibitory concentrations (MICs) consisted of 2 mg/l for all three S. aureus isolates while the bactericidal activity in vitro was not present up to the linezolid concentration of 32 mg/l. In spite of a lack of in vitro bactericidal activity, linezolid was effective in curing the patients and eradicating the infection. Trough and peak plasma concentrations of linezolid were above the MICs of the isolates. These values ranged from 3.93 to 14.95 mg/l at trough and 5.03 to 25.91 mg/l at peak. The oral bioavailability, pharmacokinetic profile and antibacterial spectrum of linezolid make this oxazolidonone antimicrobial an attractive drug for the treatment of chronic osteomyelitis. Prolonged administration requires careful surveillance for side effects, until these complications are better understood.     

Environmental Staphylococcus aureus contamination in a Tunisian hospital

One hundred hospital environment samples were obtained in 2012 in a Tunisian hospital and tested for Staphylococcus aureus recovery. Antimicrobial resistance profile and virulence gene content were determined. Multilocus-sequence-typing (MLST), spa-typing, agr-typing and SmaI-pulsed-field gel electrophoresis (PFGE) were performed. Two methicillin-resistant S. aureus (MRSA) isolates typed as: ST247-t052-SCCmecI–agrI were recovered from the intensive care unit (ICU). Ten samples contained methicillin-susceptible S. aureus (MSSA) and these samples were collected in different services, highlighting the presence of the tst gene encoding the toxic shock syndrome toxin as well as the lukED, hla, hlb, hld and hlg_v virulence genes in some of the isolates. In conclusion, we have shown that the hospital environment could be a reservoir contributing to dissemination of virulent S. aureus and MRSA.     

Risk factors associated with morbidity and operative mortality of pneumonectomy

Since the first successful one-stage pneu-monectomy for a patient with bronchogenic carcinoma was performed by Graham and Singer in 1933, it has generally been accepted that this procedure is the appropriate treatment for lung tumors that can not be completely resected by lobectomy. Pneumonectomy remains, however, a formidable operation because it carries the highest rate of morbidity and mortality of all types of lung resection. In recent 20 years, as lung cancer was able to be detected at re…     

普通外科肿瘤病人术后手术部位感染的易感因素分析

目的：探讨普外肿瘤病人术后手术部位感染（surgical site infection,SSI）的相关易感因素。方法：回顾性分析我院普外科2008年9月-2010年9月实施的638例肿瘤病人手术部位发生感染的情况。结果：638例肿瘤病人,有61例发生SSI,占9.6%。单因素分析显示SSI与手术类别、手术时间、术前预防性应用抗生素、切口类型、术前白蛋白水平、手术方式及ASA分级有明显相关性（P〈0.05）。多因素Logistic回归分析显示术前白蛋白水平、切口类型及ASA分级是诱发普外肿瘤病人SSI的独立高危因素（P〈0.05）。结论：切口类型、术前白蛋白水平以及ASA分级是SSI的独立危险因素,针对以上高危因素及早采取合理、有效的防治措施是减少普外肿瘤病人SSI的关键。     

Comparison of teicoplanin and vancomycin in vitro activity on clinical isolates of Staphylococcus aureus

Abstract

Ninety-one clinical isolates of Staphylococcus aureus have been tested with the Kirby Bauer and the Etest® method to determine the susceptibility to glycopeptides in the 2007–2010 period. Five strains (5·5%) were resistant to vancomycin and nine (9·9%) to teicoplanin. Teicoplanin showed a median minimal inhibitory concentration (MIC) of 1 mg/l (range 0·125–24 mg/l), an MIC50 of 1 mg/l, and an MIC90 of 2 mg/l; vancomycin had a median MIC of 1·5 mg/l (range 0·38–4 mg/l), an MIC50 of 1·5 mg/l, and an MIC90 of 2 mg/l. More isolates were distributed on higher values of MIC for vancomycin. Inhibition halos induced by vancomycin-impregnated paper diskettes were slightly larger than those by teicoplanin. Glycopeptide resistance among methicillin-resistant Staphylococcus aureus in Italy is an underestimated phenomenon, possibly due to the described underestimation of glycopeptides MICs by the automatic broth microdilution method, when compared to agar MIC assays. A teicoplanin MIC creep, as reported for vancomycin, cannot be assumed.     

普通外科肿瘤病人术后手术部位感染的易感因素分析

目的:探讨普外肿瘤病人术后手术部位感染(surgical site infection,SSI)的相关易感因素。方法:回顾性分析我院普外科2008年9月-2010年9月实施的638例肿瘤病人手术部位发生感染的情况。结果:638例肿瘤病人,有61例发生SSI,占9.6%。单因素分析显示SSI与手术类别、手术时间、术前预防性应用抗生素、切口类型、术前白蛋白水平、手术方式及ASA分级有明显相关性(P<0.05)。多因素Logistic回归分析显示术前白蛋白水平、切口类型及ASA分级是诱发普外肿瘤病人SSI的独立高危因素(P<0.05)。结论:切口类型、术前白蛋白水平以及ASA分级是SSI的独立危险因素,针对以上高危因素及早采取合理、有效的防治措施是减少普外肿瘤病人SSI的关键。     

结直肠癌患者术后切口感染危险因素分析

目的结直肠癌手术切口感染会导致病情加重和愈合时间延长,本研究分析结直肠癌患者术后切口感染危险因素,为制定相关防治措施提供参考。方法回顾性分析2014-01-01-2018-12-30河北医科大学第一医院普通外科接受手术治疗的282例结直肠癌患者临床资料,分析感染患者手术切口感染的相关因素和病原菌构成。结果术后切口感染17例,感染率为6.03%(17/282);开腹手术切口感染率为10.58%(11/104),腹腔镜手术切口感染率为3.37%(6/178),差异有统计学意义,P<0.05。17例切口感染者中共检出18株病原菌,革兰阳性菌6株(33.33%),革兰阴性菌10株(55.56%),真菌2株(11.11%)。单因素分析显示,结直肠癌患者术后切口感染与手术方式、患者年龄、体质量指数(body mass index,BMI)、切口长度、手术时间、是否合并糖尿病有关,均P<0.05;与患者性别、Duke分期、手术部位和术中出血量无关,均P>0.05。Logistic回归分析显示,年龄>60岁、BMI>24kg/m2、有糖尿病是结直肠癌患者术后切口感染的危险因素。结论结直肠癌患者术后切口感染的发生与手术方式、患者年龄、BMI、切口长度、手术时间、是否合并糖尿病有关,应采取针对性的防治措施,以降低结直肠癌患者术后切口感染的发生。     

Lincomycin Resistance in Methicillin-Resistant Staphylococcus aureus Strains of Hospital Origin

Summary

A total of 170 Staphylococcus aureus strains isolated during a one-year period at the University Hospital of Patras Medical School were examined for resistance to a battery of antimicrobial agents by disk diffusion and minimum inhibitory concentration (MIC) determination. Fifty-five isolates were lincomycin- and methicillin-resistant (LMRSA). In the group of 55 LMRSA isolates 13 were also resistant to vancomycin. All the LMRSA isolates were not typed by the international set and the experimental phages 88A and 25 at routine typing dilution (RTD), while 18 isolates were lysed by phages at 100XRTD and 1000XRTD. Reverse phage-typing and heat shock treatment of the LMRSA isolates had no effect on their typability. Plasmid profiles coupled with restriction endonuclease analysis of plasmid DNA established that the LMRSA isolates represent different strains. Membrane-protein profiles by polyacrylamide gel electrophoresis (PAGE) showed that LMRSA strains could belong to one group. This method proved useful and sensitive for characterization of LMRSA.     

Linezolid as Rescue Drug: A Clinical Case of Soft Tissue Infection Caused by a Staphylococcus aureus Strain Resistant In Vivo to Teicoplanin

Abstract

The authors report and discuss a patient admitted to intensive care unit (ICU) for acute respiratory failure due to upper airway obstruction caused by face and neck soft tissue infection. An oxacillin-resistant Staphyloccoccus aureus was isolated from necrotic skin lesions and from skin biopsy. The strain was susceptible in vitro to teicoplanin, but it showed resistance In Vivo, despite appropriate dosage. After 6 days of full dose therapy, since the clinical course worsened, teicoplanin was interrupted and linezolid was started. In 48 hours signs of infection regressed, and the patient was discharged from the ICU after 10 days of linezolid treatment. Linezolid resulted as a rescue drug for a life-threatening infection.     

乳腺癌术后化疗患者感染的影响因素分析

目的：分析乳腺癌患者术后化疗发生感染的影响因素,并提出相应的干预对策。方法回顾性分析268例乳腺癌术后化疗患者的感染可能相关因素,并对相关因素进行Logistic分析。结果本研究患者感染率为17.16%,其中呼吸道感染20例,皮肤软组织感染9例,口腔黏膜感染7例,其他感染10例;经Logistic回归分析,化疗周期﹥3个,抗菌使用药物﹥2种,白细胞计数﹤4×109/L,血清白蛋白﹤35 g/L,CD4+/CD8+值﹥1.33,年龄≥60岁,行乳腺癌扩大根治术是乳腺癌患者术后化疗发生感染的危险因素,差异有统计学意义（P﹤0.01）。结论对于白细胞计数过低,化疗3个周期以上,免疫力低下的乳腺癌术后化疗老年患者应采取积极预防措施。     

肺癌患者医院感染危险因素分析

目的:探讨肺癌患者医院感染的特点与危险因素及其对预后的影响。方法:回顾调查我院1 280例肺癌的患者临床资料,对医院感染各种危险因素分别进行单因素和多因素分析。结果:1 280例肺癌出院病例中,98例(7.7%)发生医院感染,感染部位依次为呼吸系(73.5%)、胃肠系(11.2%)和泌尿系(8.2%)等。医院感染的病原菌多为耐药的条件致病菌和真菌,以革兰氏阴性菌为主,占56.7%,真菌占23.0%。医院感染与年龄(P=0.033)、临床分期(P=0.001)、PS评分(P=0.015)、侵入性操作(P=0.000)、手术(P=0.029)、放疗(P=0.022)、化疗(P=0.001)、贫血(P=0.000)、中性粒细胞减少(P=0.000)、使用抗生素(P=0.035)、使用激素(P=0.000)、血清白蛋白降低(P=0.000)、合并糖尿病(P=0.019)以及住院时间(P=0.000)密切相关。Logistic多因素分析显示,临床分期(P=0.024)、PS评分(P=0.012)、侵入性操作(P=0.000)、化疗(P=0.000)、贫血(P=0.036)、中性粒细胞减少(P=0.001)和住院时间(P=0.000)是肺癌患者发生医院感染的独立危险因素。医院感染不但延长患者的住院时间,还增加患者的病死率。结论:肺癌患者是医院感染的高危人群,医院感染是多种因素共同作用的结果;控制感染的危险因素,规范抗肿瘤治疗,提高机体免疫力是防控肺癌患者医院感染的主要措施。     

肺癌患者下呼吸道感染的现状及危险因素分析

目的探讨肺癌患者下呼吸道感染的现状及危险因素。方法选择2009年11月至2011年10月收治的肺癌患者110例,观察患者是否发生下呼吸道感染,分析患者性别、年龄、吸烟史、肺癌分期、住院时间、侵人性操作、抗生素应用是否为下呼吸道感染发生的危险因素。结果110例肺癌患者发生下呼吸道感染者71例,发生率为64．5％,以革兰阴性菌感染为主,其发生明显受到患者年龄、吸烟史、肺癌分期、住院时间、侵入性操作、抗生素应用的影响（P〈0．05）。结论肺癌患者的年龄、吸烟史、肺癌分期、住院时间、侵人性操作、抗生素应用均为发生下呼吸道感染的危险因素,临床工作中应该针对可干预的危险因素采取有效的预防措施,提高患者的生活质量。     

In vitro activity of ceftaroline and ceftobiprole against methicillin-resistant Staphylococcus aureus with decreased susceptibility to vancomycin isolated in paediatric patients

Minimal inhibitory concentrations (MIC, mg/l) of ceftaroline and ceftobiprole were evaluated over 70 methicillin-resistant Staphylococcus aureus (MRSA) strains with vancomycin MIC ≥1 isolated in a paediatric hospital. The proportion of non-wild-type strains (MIC?>?epidemiological cut off) was 18% for ceftobiprole and 64% for ceftaroline. Only 1.4% of strains was resistant to ceftobiprole, and none to ceftaroline. These results are worrisome, since show the presence of non-negligible proportions of MRSA strains with high MIC values for ceftaroline and ceftobiprole in a setting where both drugs were never used.     

Effect of vancomycin initial dosing on time to systemic inflammatory response syndrome resolution in patients with methicillin-resistant Staphylococcus aureus bacteremia

Current guidelines suggest using vancomycin-loading doses for complicated infections despite a lack of evidence to support this practice. To address this gap, we performed a single-centre cohort study of 124 patients with sepsis due to methicillin-resistant Staphylococcus aureus bacteremia. Patients were allocated into two groups based on initial dose of vancomycin, <20 mg/kg or ≥20 mg/kg, and evaluated for time to resolution of systemic inflammatory response syndrome (SIRS). Among a cohort of 124 patients, 87 received vancomycin initial doses <20 mg/kg and 37 received ≥20 mg/kg. The median time to SIRS resolution was 109 h in the <20 mg/kg group compared to 67 h in the ≥20 mg/kg group. Cox proportional hazard modelling showed a faster resolution of SIRS in the ≥20 mg/kg group (HR = 1.72[1.09–2.73]). Vancomycin initial doses of ≥20 mg/kg led to faster resolution of SIRS although further studies are needed to evaluate the safety and efficacy of this approach.     

晚期肿瘤患者交叉感染的特点及临床分析

目的探讨晚期肿瘤患者交叉感染的特点及其相关危险因素。方法采用回顾性分析的方法对986例晚期肿瘤患者进行分析。结果 986例晚期肿瘤患者中,男573例（58.1%）,女413例（41.9%）,中位年龄为65岁。卡式评分（KPS评分）中位数60分,平均住院日为14 d,死亡124例,住院病死率为12.6%,其中231例晚期肿瘤患者发生交叉感染,占23.4%,因感染死亡39例。单因素分析结果显示,感染与年龄、KPS评分、放疗、化疗后粒细胞减少、远处转移、气管切开等因素有关,差异有统计学意义（P〈0.05）。多因素分析结果显示,高龄、白细胞计数（WBC）〈2.0×10^9/L、远处转移以及气管切开与晚期肿瘤患者发生感染显著相关。结论感染是晚期肿瘤患者最主要的死亡原因之一,高龄、WBC〈2.0×10^9/L、远处转移以及气管切开是晚期肿瘤患者发生感染的危险因素。     

Effect of Ceftriaxone on the Phagocytosis and Intracellular Killing of Staphylococcus aureus by Human Macrophages

Summary

The efficacy of an antimicrobial agent in the treatment of infections depends upon the interactions of bacteria, antibiotic and phagocytes. The influence of ceftriaxone on the phagocytic and bactericidal activity of human macrophages in vitro and ex vivo was investigated. At concentrations one-half the minimum inhibitory concentration (½ × MIC) the antibiotic caused in vitro a significant enhancement of phagocytosis and a reduction in the survival of intracellular Staphylococcus aureus. The distinction between any effect of ceftriaxone on the staphylococci and the macrophages was made by exposure of each of them to the antibiotic before they were incubated together. The results suggest that ceftriaxone may have a direct positive action on macrophages, possibly by interfering with the cellular membrane functions and hence enhancing engulf ment of bacteria. The ex vivo data seem to corroborate this hypothesis.     

老年脑肿瘤患者术后脑脊液感染的危险因素分析

目的:探讨老年脑肿瘤患者术后脑脊液感染的危险因素。方法:选择于2015年1月至2018年8月在我院接受诊治的老年脑肿瘤患者147例,根据是否发生术后脑脊液感染分为感染组34例与未感染组113例。采用单因素分析术后脑脊液感染相关因素,采用多因素Logistic回归分析影响术后脑脊液感染危险因素。调查资料包括性别、平均BMI、合并高血压、合并糖尿病、合并冠心病、吸烟史、饮酒史、肿瘤大小、后颅窝手术、手术时间、脑室外引流、颅内感染灶。结果:老年脑肿瘤147例患者,发生术后脑脊液感染34例,感染率为23.13%。单因素分析显示,两组性别、平均BMI、合并高血压、合并糖尿病、合并冠心病、吸烟史和饮酒史比较无统计学意义（P＞0.05）;感染组肿瘤＞5 cm多于未感染组、后颅窝手术多于未感染组、手术时间＞3 h多于未感染组、脑室外引流多于未感染组、颅内感染灶多于未感染组,差异具有统计学意义（P＜0.05）。将上述单因素分析具有统计学意义的纳入多因素Logistic回归分析显示,肿瘤＞5 cm、后颅窝手术、手术时间＞3 h、脑室外引流和颅内感染灶为影响术后脑脊液感染危险因素。结论:老年脑肿瘤患者术后脑脊液感染受多种因素影响,其中肿瘤大小、后颅窝手术、手术时间、脑室外引流和颅内感染灶为其危险因素,值得临床借鉴。