Effect of Linezolid on Clinical Severity and Pulmonary Cytokines in a Murine Model of Influenza A and Staphylococcus aureus Coinfection

Excessive inflammation contributes to the severity of post influenza pneumonia caused by methicillin resistant S.aureus (MRSA). Linezolid, vancomycin, and clindamycin are antibiotics used for MRSA infections. Linezolid has immunomodulatory properties. We report on the effects of the three antibiotics on microbial clearance, pulmonary cytokines and clinical course in a murine model of influenza and MRSA coinfection.

Methods

B6 mice were infected with influenza A virus and 3 days later with MRSA, both intranasally. Treatment with placebo, linezolid, vancomycin or clindamycin started immediately after MRSA infection and continued for 72 hours. Bacterial and viral titers as well as cytokine concentrations in the lungs were assessed 4 and 24 hours after MRSA coinfection. Mice were weighted daily for 13 days.

Results

Coinfected mice had increased pulmonary IL-1β, TNF-α and mKC at 4 and 24 hours, IL-6, IL-10 and IL-12 at 4 hours and IFN-γ at 24 hours after MRSA coinfection (all P<0.05). Compared to placebo, coinfected mice treated with linezolid, vancomycin or clindamycin had decreased pulmonary IL-6 and mKC at 4 hours and IFN-γ at 24 hours after MRSA coinfection (all P<0.05). IL-1β, TNF-α and IL-12 were similar in antibiotic-treated and placebo groups. All antibiotics similarly reduced MRSA without effect on influenza titers. Linezolid-treated mice had less weight loss on days 4–6 after influenza infection compared to placebo (all P<0.05). On all other days weight change was similar among all groups.

Conclusions

This is the first report comparing the effects of antibiotics on cytokines and clinical outcome in a murine model of influenza and MRSA coinfection. Compared to placebo, antibiotic treatment reduced maximum concentration of IL-6, mKC and IFN-γ in the lungs without any difference among antibiotics. During treatment, only linezolid delayed weight loss compared to placebo.     

Multi-drug resistant Bacteroides fragilis recovered from blood and severe leg wounds caused by an improvised explosive device (IED) in Afghanistan

This report summarizes the case of a 23 year-old otherwise healthy male that was injured in an improvised explosive device (IED) blast in support of Operation Enduring Freedom (OEF). He sustained bilateral open tibia and fibula fractures in the setting of being exposed to water contaminated with raw sewage. Despite long-term carbapenem therapy, the patient's wounds were repeatedly noted to have purulent drainage during surgical debridement and cultures from these wounds were persistently positive for Bacteroides fragilis. Apparent clinical failure persisted despite the addition of metronidazole to his regimen and an eventual trial of tigecycline. Susceptibility testing of the B.?fragilis isolate was performed and resistance to penicillin, clindamycin,metronidazole, cefoxitin, meropenem, imipenem, piperacillin/tazobactam, and tigecycline was confirmed. The presence of a nimE gene on a potentially transferrable plasmid was also confirmed by plasmid sequencing. The only antibiotics that displayed in vitro susceptibility were moxifloxacin and linezolid. These antibiotics were initiated in combination with aggressive irrigation and serial surgical debridement. Conversion to left-sided internal fixation became feasible and his left lower extremity was salvaged without residual evidence of infection. The patient completed an eight week course of combination moxifloxacin and linezolid therapy without adverse event. This B.?fragilis isolate displayed simultaneous high-level resistance to multiple antibiotics routinely utilized in anaerobic infections. This was evidenced by clinical failure, in vitro susceptibility testing, and demonstration of genes associated with resistance mechanisms. This case warrants review not only due to the rarity of this event but also the potential implications regarding anaerobic infections in traumatic wounds and the success of a novel treatment regimen utilizing combination therapy with moxifloxacin and linezolid.     

Linezolid for the treatment of nosocomial infections after cardiac surgery]

Clinical and bacteriological efficacy of linezolid in the treatment of cardiosurgical patients with various localization nosocomial infections due to problem grampositive cocci was estimated. The group included 10 patients: children at the age 3 months to 12 years (n = 3) and adults at the age of 17 to 65 years (n = 7) with infectious complications such as infectious endocarditis (n = 4), pneumonia (n = 2), wound infection (n = 3) and sepsis (n = 1). All the patients isolated MR staphylococci. The use of glycopeptides was not possible in 6 patients because of vancomycin intolerance (n = 1), renal insufficiency (n = 1) and failure of the previous vancomycin therapy (n = 4). To all the patients linezolid was administered per os (tablets or suspension) or intravenously (infusion solution) in doses of 600 mg twice a day (1200 mg a day) for the adults and 10 mg/kg body weight every 12 hours (20 mg/kg body weight a day) for the children. Linezolid monotherapy was applied to 2 patients. 8 patients were treated with linezolid in combination with some other antibiotics. By the clinical findings the positive dynamics confirmed by thermometry and hemograms was observed in 8 patients beginning from the 4th day of the linezolid use. Eradication of MR staphylococci from the blood, sputum and wounds was stated in all 10 patients. No toxic or adverse reactions were noted. It was concluded that linezolid is an optimal alternative to vancomycin especially when the use of the latter is not possible. No nephrotoxic effects of linezolid provided its recommendation as a drug of choice in the treatment of patients with renal disturbances, including polyorganic insufficiency.     

In vitro Activity of Daptomycin,Linezolid and Rifampicin on <Emphasis Type="Italic">Staphylococcus epidermidis</Emphasis> Biofilms

Owing to their massive use, Staphylococcus epidermidis has recently developed significant resistance to several antibiotics, and became one of the leading causes of hospital-acquired infections. Current antibiotics are typically ineffective in the eradication of bacteria in biofilm-associated persistent infections. Accordingly, the paucity of effective treatment against cells in this mode of growth is a key factor that potentiates the need for new agents active in the prevention or eradication of biofilms. Daptomycin and linezolid belong to the novel antibiotic therapies that are active against gram-positive cocci. On the other hand, rifampicin has been shown to be one of the most potent, prevalent antibiotics against S. epidermidis biofilms. Therefore, the main aim of this study was to study the susceptibility of S. epidermidis biofilm cells to the two newer antimicrobial agents previously mentioned, and compare the results obtained with the antimicrobial effect of rifampicin, widely used in the prevention/treatment of indwelling medical device infections. To this end the in vitro activities of daptomycin, linezolid, and rifampicin on S. epidermidis biofilms were accessed, using these antibiotics at MIC and peak serum concentrations. The results demonstrated that at MIC concentration, rifampicin was the most effective antibiotic tested. At peak serum concentration, both strains demonstrated similar susceptibility to rifampicin and daptomycin, with colony-forming units (CFUs) reductions of approximately 3–4 log₁₀, with a slightly lower response to linezolid, which was also more strain dependent. However, considering all the parameters studied, daptomycin was considered the most effective antibiotic tested, demonstrating an excellent in vitro activity against S. epidermidis biofilm cells. In conclusion, this antibiotic can be strongly considered as an acceptable therapeutic option for S. epidermidis biofilm-associated infections and can represent a potential alternative to rifampicin in serious infections where rifampicin resistance becomes prevalent.     

Pre-treatment of central venous catheters with the cathelicidin BMAP-28 enhances the efficacy of antistaphylococcal agents in the treatment of experimental catheter-related infection

An in vitro antibiotic susceptibility assay for Staphylococcus aureus biofilms developed on 96-well polystyrene tissue culture plates was performed to elucidate the activity of the 27 residues cathelicidin peptide BMAP-28, quinupristin/dalfopristin (Q/D), linezolid, and vancomycin. Efficacy studies were performed in a rat model of staphylococcal CVC infection. Silastic catheters were implanted into the superior cava. Twenty-four hours after implantation the catheters were filled with BMAP-28. Thirty minutes later rats were challenged via the CVC with 1.0x10(6) CFU of S. aureus strain Smith diffuse. Administration of antibiotics into the CVC at a concentration equal to the MBC observed using adherent cells, or at a much higher concentration (1024 microg/mL) began 24 h later. The inhibition activities of all antibiotics against adherent bacteria were at least two-four-fold lower that against freely growing cells. When antibiotics were used in BMAP-28 pre-treated wells, they showed higher activities. The in vivo studies showed that when CVCs were pre-treated with BMAP-28 or with a high dose of antibiotics, biofilm bacterial load was reduced from 10(7) to 10(3) CFU/mL and bacteremia reduced from 10(3) to 10(1) CFU/mL. When CVCs were treated with both BMAP-28 and antibiotics, biofilm bacterial load was further decreased to 10(1) CFU/mL and bacteremia was not detected. These results suggest that CVC pre-treated with BMAP-28 represents an attractive choice for the treatment of device-related infections caused by staphylococci.     

Impact of Molecular Epidemiology and Reduced Susceptibility to Glycopeptides and Daptomycin on Outcomes of Patients with Methicillin-Resistant Staphylococcus aureus Bacteremia

Background

Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia was associated with high mortality, but the risk factors associated with mortality remain controversial.

Methods

A retrospective cohort study was designed. All patients with MRSA bacteremia admitted were screened and collected for their clinical presentations and laboratory characteristics. Minimum inhibitory concentration (MIC) and staphylococcal cassette chromosome mec (SCCmec) type of bacterial isolates were determined. Risk factors for mortality were analyzed.

Results

Most MRSA isolates from the 189 enrolled patients showed reduced susceptibility to antibiotics, including MIC of vancomycin ≥ 1.5 mg/L (79.9%), teicoplanin ≥ 2 mg/L (86.2%), daptomycin ≥ 0.38 mg/L (73.0%) and linezolid ≥ 1.5 mg/L (64.0%). MRSA with vancomycin MIC ≥ 1.5 mg/L and inappropriate initial therapy were the two most important risk factors for mortality (both P < 0.05; odds ratio = 7.88 and 6.78). Hospital-associated MRSA (HA-MRSA), carrying SCCmec type I, II, or III, was associated with reduced susceptibility to vancomycin, teicoplanin or daptomycin and also with higher attributable mortality (all P < 0.05). Creeping vancomycin MIC was linked to higher MIC of teicoplanin and daptomycin (both P < 0.001), but not linezolid (P = 0.759).

Conclusions

Giving empirical broad-spectrum antibiotics for at least 5 days to treat catheter-related infections, pneumonia, soft tissue infection and other infections was the most important risk factor for acquiring subsequent HA-MRSA infection. Choice of effective anti-MRSA agents for treating MRSA bacteremia should be based on MIC of vancomycin, teicoplanin and daptomycin. Initiation of an effective anti-MRSA agent without elevated MIC in 2 days is crucial for reducing mortality.     

屎肠球菌的临床分布与耐药性分析

目的了解医院屎肠球菌的临床分布和耐药情况,为临床抗感染的预防与治疗提供参考。方法回顾性分析1999年1月至2011年12月临床标本中分离的1161株屎肠球菌;用WHONET5．6软件分析耐药率变迁。结果临床分离的1161株屎肠球菌,在同期分离的1944株肠球菌属中占59．72％。主要分离自尿液和血液,分别占40．91％和26．87％;主要分离自外科病区、内科病区、ICU和儿科病区的菌株,分别占29．37％、25．15％、13．95％和13．53％;屎肠球菌对多种抗菌药物耐药,对万古霉素、替考拉宁和利奈唑胺的耐药率较低,分别为1．04％、0．94％和1．85％。结论屎肠球菌在临床的分离率逐年增加,已成为医院内感染的主要病原菌之一,其多药耐药和高耐药现象相当严重,目前万古霉素、替考拉宁和利奈唑胺仍然是治疗肠球菌属引起感染的有效药物。     

Discovery,pharmacology, and clinical profile of omadacycline,a novel aminomethylcycline antibiotic

Omadacycline is novel, aminomethyl tetracycline antibiotic being developed for oral and intravenous (IV) administration for the treatment of community-acquired bacterial infections. Omadacycline is characterized by an aminomethyl substituent at the C9 position of the core 6-member ring. Modifications at this position result in an improved spectrum of antimicrobial activity by overcoming resistance known to affect older generation tetracyclines via ribosomal protection proteins and efflux pump mechanisms. In vitro, omadacycline has activity against Gram-positive and Gram-negative aerobes, anaerobes, and atypical pathogens including Legionella and Chlamydia spp. Omadacycline offers once daily oral and IV dosing and a clinical tolerability and safety profile that compares favorably with contemporary antibiotics used across serious community-acquired infections where resistance has rendered many less effective. In studies in patients with complicated skin and skin structure infections, including those with MRSA infections, omadacycline exhibited an efficacy and tolerability profile that was comparable to linezolid. Ongoing and planned clinical studies are evaluating omadacycline as monotherapy for treating serious community-acquired bacterial infections including Acute Bacterial Skin and Skin Structure Infections (ABSSSI) and Community-Acquired Bacterial Pneumonia (CABP). This review provides an overview of the discovery, microbiology, nonclinical data, and available clinical safety and efficacy data for omadacycline, with reference to other contemporary tetracycline-derived antibiotics.     

耐甲氧西林金黄色葡萄球菌的分布及耐药性分析

目的分析医院耐甲氧西林金黄色葡萄球菌（MRSA）的分布及耐药情况,为临床治疗金黄色葡萄球菌医院感染提供科学依据。方法对618株金黄色葡萄球菌进行常规鉴定,用K—B法对其进行药敏试验。结果5年MRSA的平均检出率为51．9％（321／618）,MRSA感染高发主要科室为ICU、神经外科、神经内科,MRSA检出率前三位的科室为神经外科（84．1％）、ICU（76．3％）、呼吸内科（61．3％）,标本来源主要为痰液,占67．3％,检出率82．4％。MRSA对万古霉素、替考拉宁、利奈唑胺保持100％敏感,对氯霉素、米诺环素、复方新诺明等的耐药率较低,对其他药物都保持了65％以上的高耐药率。结论对重点科室监控,合理使用抗生素,严格执行无菌操作,采取有效的消毒隔离,尽量减少侵袭性操作等措施是控制并减少MRSA感染的重要环节。     

Time-kill study and synergistic activity of cell-wall inhibitor antibiotics in combination with gentamicin against Enterococcus faecalis and Enterococcus faecium

The synergy between gentamicin and vancomycin, teicoplanin, ampicillin and linezolid was studied by time-kill method. Two clinical vancomycin resistant enterococci (VRE) and two vancomycin susceptible enterococci (VSE) isolates were used. Different concentrations of antibiotics were combined. Two VSE strains and the control strain exhibited synergism with the combination of gentamicin, vancomycin, teicoplanin, ampicillin and linezolid. Two VRE strains exhibited synergism with the combination of gentamicin and ampicillin. Synergy between gentamicin and vancomycin, teicoplanin and linezolid was not observed against these isolates. The VRE isolates were positive for vanA, aac (6')-Ie aph (2") and aph (3')-IIIa genes and their vancomycin, teicoplanin and gentamicin MICs were 512 μg/ml, 512 μg/ml and >4000 μg/ml, respectively. In order to treat serious enterococcal infections, further clinical evaluation is needed to examine the in vitro combined effects of gentamicin and vancomycin, teicoplanin and linezolid.     

A combination of silver nanoparticles and visible blue light enhances the antibacterial efficacy of ineffective antibiotics against methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> (MRSA)

Background

Silver nanoparticles (AgNPs) are potential antimicrobials agents, which can be considered as an alternative to antibiotics for the treatment of infections caused by multi-drug resistant bacteria. The antimicrobial effects of double and triple combinations of AgNPs, visible blue light, and the conventional antibiotics amoxicillin, azithromycin, clarithromycin, linezolid, and vancomycin, against ten clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) were investigated.

Methods

The antimicrobial activity of AgNPs, applied in combination with blue light, against selected isolates of MRSA was investigated at 1/2–1/128 of its minimal inhibitory concentration (MIC) in 24-well plates. The wells were exposed to blue light source at 460 nm and 250 mW for 1 h using a photon emitting diode. Samples were taken at different time intervals, and viable bacterial counts were determined. The double combinations of AgNPs and each of the antibiotics were assessed by the checkerboard method. The killing assay was used to test possible synergistic effects when blue light was further combined to AgNPs and each antibiotic at a time against selected isolates of MRSA.

Results

The bactericidal activity of AgNPs, at sub-MIC, and blue light was significantly (p < 0.001) enhanced when both agents were applied in combination compared to each agent alone. Similarly, synergistic interactions were observed when AgNPs were combined with amoxicillin, azithromycin, clarithromycin or linezolid in 30–40 % of the double combinations with no observed antagonistic interaction against the tested isolates. Combination of the AgNPs with vancomycin did not result in enhanced killing against all isolates tested. The antimicrobial activity against MRSA isolates was significantly enhanced in triple combinations of AgNPs, blue light and antibiotic, compared to treatments involving one or two agents. The bactericidal activities were highest when azithromycin or clarithromycin was included in the triple therapy compared to the other antibiotics tested.

Conclusions

A new strategy can be used to combat serious infections caused by MRSA by combining AgNPs, blue light, and antibiotics. This triple therapy may include antibiotics, which have been proven to be ineffective against MRSA. The suggested approach would be useful to face the fast-growing drug-resistance with the slow development of new antimicrobial agents, and to preserve last resort antibiotics such as vancomycin.

     

预防性应用抗生素对糖皮质激素治疗老年ITP并发感染的影响

目的:探讨预防性应用抗生素对糖皮质激素治疗老年特发性血小板减少性紫癜并发感染的影响。方法:将哈尔滨医科大学附属第二医院血液科2012年3月~2015年3月的收治的72例老年特发性血小板减少性紫癜患者随机分为两组,自应用糖皮质激素第一天开始观察15天,观察组自应用糖皮质激素开始即使用抗生素,对照组不常规应用抗生素,以出现感染症状即开始应用抗生素,同时定为观察终止。比较两组患者感染发生率的差异。结果:观察组感染发生率为38.89%,对照组为69.44%,较观察组显著升高,差异有统计学意义(P0.05)。两组患者感染发生部分的分布情况比较无统计学差异(P0.05),以呼吸系统感染发生率最高,其次是尿路感染。结论:预防性的使用抗生素可以降低糖皮质激素治疗老年特发性血小板减少性紫癜患者过程中感染的发生率。     

Antimicrobial activity of mupirocin, daptomycin, linezolid, quinupristin/dalfopristin and tigecycline against vancomycin-resistant enterococci (VRE) from clinical isolates in Korea (1998 and 2005)

It is a hot clinical issue whether newly approved antimicrobial agents such as daptomycin, linezolid, quinupristin/dalfopristin (synercid) and tigecycline are active enough to be used for infections caused by vancomycin resistant bacteria. We performed susceptibility tests for mupirocin, which is in widespread clinical use in Korea, and four new antimicrobials, daptomycin, linezolid, quinupristin/dalfopristin and tigecycline, against vancomycin-resistant Enterococcus faecalis and Enterococcus faecium isolated from Korean patients in 1998 and 2005 to evaluate and compare the in vitro activity of these antimicrobials. Among these agents, quinupristin/dalfopristin, which is rarely used in hospitals in Korea, showed relatively high resistance to several vancomycin-resistant enterococci (VRE) isolated in 2005. Likewise, daptomycin, linezolid and tigecycline have not yet been in clinical use in Korea. However, our results showed that most of the 2005 VRE isolates were already resistant to linezolid and daptomycin (highest minimum inhibitory concentration (MIC) value >100 microg/ml). Compared with the other four antimicrobial agents tested in this study, tigecycline generally showed the greatest activity against VRE. However, four strains of 2005 isolates exhibited resistance against tigecycline (MIC >12.5 microg/ml). Almost all VRE were resistant to mupirocin, whereas all E. faecium isolated in 1998 were inhibited at concentrations between 0.8 to approximately 1.6 microg/ml. In conclusion, resistances to these new antimicrobial agents were exhibited in most of VRE strains even though these new antibiotics have been rarely used in Korean hospitals.     

侵袭性和非侵袭性肺炎链球菌耐药率的比较分析

目的研究侵袭性和非侵袭性肺炎链球菌的耐药谱的差异,指导合理应用抗生素及感染管理。方法回顾性统计分析2009至2011年来天台县人民医院就诊患者分离肺炎链球菌的标本来源及耐药性,比较侵袭性和非侵袭性肺炎链球菌耐药率之间的差异。结果共分离出肺炎链球菌642株,痰液中分离出584株,非痰液中分离出58株,其中血液中分离出32株,脑脊液中分离出20株,其他分离出6株,所有肺炎链球菌对万古霉素和利奈唑胺均敏感,对青霉素、红霉素、克林霉素、四环素及复方新诺明耐药严重,对左氧氟沙星、氯霉素比较敏感;侵袭性分离株对青霉素、红霉素、克林霉素、左氧氟沙星、四环素及氯霉素的耐药率显著高于非侵袭性肺炎链球菌。结论该院分离的肺炎链球菌主要来自痰液标本,耐青霉素肺炎链球菌的检出率高,大环内酯类耐药严重,存在一定比例的侵袭性感染,非侵袭菌株与侵袭性菌株耐药谱之间存在一定差异,临床治疗应该区别对待,系统的监测细菌耐药性,合理选择抗菌药物。     

Studies of stage-specific immunity against Trichostrongylus colubriformis in sheep: immunization by normal and truncated infections.

Sheep immunized with multiple normal infections of 30,000 Trichostrongylus colubriformis larvae (T.c. L3) suppressed the fecundity, establishment and survival of adoptively transferred adult worms, showing that these parasites were susceptible to the effects of host immunity. When sheep were immunized by four 'truncated' larval infections of 4, 7 or 10 days' (d) duration with 10(5) T.c. L3, animals given 4 x 4d infections were susceptible to challenge, whereas sheep given 4 x 7d and 4 x 10d infections were significantly protected. A serial analysis of the rejection of T. colubriformis from nine sheep given 5 x 7d infections revealed that the challenge larval infection given intraduodenally was expelled within 3 days after challenge (DAC). However, another five of these sheep only rejected around 50% of transferred adult worms by 21 DAC when compared with control animals. The results indicate that stage-specific antigens produced by early L3 and L4 stages of T. colubriformis effectively immunize sheep against a larval challenge but appear less reliably protective against adult worms.     

The Efficacy and Safety of Linezolid and Glycopeptides in the Treatment of Staphylococcus aureus Infections

To assess the effectiveness and safety of linezolid in comparison with glycopeptides (vancomycin and teicoplanin) for the treatment of Staphylococcus aureus infections, we conducted a meta-analysis of relevant randomized controlled trials. A thorough search of Pubmed and other databases was performed. Thirteen trials on 3863 clinically assessed patients were included. Linezolid was slightly more effective than glycopeptides in the intent-to-treat population (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01–1.10), was more effective in clinically assessed patients (OR 95% CI: 1.38, 1.17–1.64) and in all microbiologically assessed patients (OR 95% CI: 1.38, 1.15–1.65). Linezolid was associated with better treatment in skin and soft-tissue infections (SSTIs) patients (OR 95% CI: 1.61, 1.22–2.12), but not in bacteraemia (OR 95% CI: 1.24, 0.78–1.97) or pneumonia (OR 95% CI: 1.25, 0.97–1.60) patients. No difference of mortality between linezolid and glycopeptides was seen in the pooled trials (OR 95% CI: 0.98, 0.83–1.15). While linezolid was associated with more haematological (OR 95% CI: 2.23, 1.07–4.65) and gastrointestinal events (OR 95% CI: 2.34, 1.53–3.59), a significantly fewer events of skin adverse effects (OR 95% CI: 0.27, 0.16–0.46) and nephrotoxicity (OR 95% CI: 0.45, 0.28–0.72) were recorded in linezolid. Based on the analysis of the pooled data of randomized control trials, linezolid should be a better choice for treatment of patients with S. aureus infections, especially in SSTIs patients than glycopeptides. However, when physicians choose to use linezolid, risk of haematological and gastrointestinal events should be taken into account according to the characteristics of the specific patient populations.     

尿路感染相关病原菌的分布及耐药性分析

目的调查尿路感染病原菌的分布和耐药特点,为临床的抗感染治疗提供依据。方法收集2013年至2015年荆州市中心医院门诊和住院患者中,尿路感染患者送检的尿培养和血培养标本中检出的病原菌,采用Vitek2 Compact全自动微生物检测仪进行细菌鉴定,采用纸片扩散法和仪器法分别对革兰阴性杆菌和革兰阳性球菌进行药敏试验,药敏结果的判断依照CLSI M100-S24标准。数据分析采用WHONET5.6和SPSS 19.0软件,统计分析采用x~2检验。结果从尿路感染患者送检的标本中共检出各类非重复病原菌2 306株,其中门诊患者中检出19种100株,住院患者检出56种2 206株。导致尿路感染最多的两种病原菌为大肠埃希菌和粪肠球菌,分别检出1 241株和232株。导致尿脓毒血症最多的两种病原菌为大肠埃希菌和肺炎克雷伯菌,分别检出36株和10株。大肠埃希菌产ESBL.s率达67.9%,其对多种抗菌药物的耐药性均高于60.0%。粪肠球菌对大多数抗菌药物的耐药性均高于50.0%,仅对呋喃妥因和高浓度链霉素的耐药性较低,分别为12.0%和38.7%;未检出对万古霉素、利奈唑胺和替加环素耐药的粪肠球菌。结论导致尿路感染的病原菌种类繁多,大肠埃希菌和粪肠球菌是主要病原菌,其耐药情况严重;为保证治疗的有效性,临床医生应注重相关病原学和药敏检查结果。     

嗜麦芽窄食单胞菌感染的临床特征、高危因素及预后分析

目的了解嗜麦芽窄食单胞菌感染的临床特点、危险因素、预后及耐药现状,为有效预防和治疗该病原菌感染提供依据。方法收集2013年11月至2014年4月浙江大学医学院附属第一医院收治的129例细菌培养为嗜麦芽窄食单胞菌患者的临床资料进行回顾性统计分析。结果 129例细菌培养确诊嗜麦芽窄食单胞菌感染患者平均年龄（65.1±17.0）岁,包括下呼吸道感染和非呼吸道感染患者分别为100例和29例,下呼吸道感染患者存在原发肺部疾病的患病率、ICU入住率、气管切开比例、广谱抗生素的使用率、患病年龄等均高于非呼吸道感染患者（P〈0.05）。而非呼吸道感染患者的外科手术、无菌腔内置管比例及免疫抑制剂使用率高于下呼吸道感染患者（P〈0.05）。嗜麦芽窄食单胞菌感染后选择敏感抗生素治疗的患者的死亡率明显低于未选择敏感抗生素的患者（15.0%/30.4%,P〈0.05）。结论原发肺部疾病、入住ICU、气管切开、广谱抗生素使用、年龄大是下呼吸道感染嗜麦芽窄食单胞菌的高危因素,外科手术、无菌腔内置管、免疫抑制剂使用是非呼吸道感染嗜麦芽窄食单胞菌的高危因素。使用敏感抗生素可以降低嗜麦芽窄食单胞菌感染患者的死亡率。     

动态监测血清降钙素原水平在优化全身性感染患者抗菌治疗策略中的价值

目的:评估动态监测血清降钙素原水平(PCT)在优化全身性感染患者抗菌治疗策略中的价值。方法:选取2015年4月~2015年12月全身性感染患者85例,随机分为常规组42例和PCT组43例。常规组按照《抗菌药物临床应用指导原则(2015年版)》决定抗生素疗程;PCT组在抗生素治疗后第3、5、7、10、14 d监测血清PCT水平,若PCT0.25 ng/mL停用抗生素、PCT≥0.25 ng/mL继续使用抗生素。分别比较两组患者间一般情况、传统全身炎症性反应指标及抗生素使用的种类、时间、费用以及预后的差异。结果:两组患者间治疗前后传统全身炎症性反应指标无明显差异(P0.05);两组患者间常用的抗生素种类并无明显统计学差异(P0.05);PCT组患者抗生素使用的天数为(9.9±3.9)d,明显少于常规组的(13.9±5.2)d,差异有统计学意义(P0.05);PCT组患者抗生素日均费用为(422.39±139.9)元,明显低于常规组的(514.78±155.2)元,差异有统计学意义(P0.05);两组患者间停用抗生素后14天后全身感染复发率以及28天病死率无明显统计学差异(P0.05)。但PCT组患者总住ICU时间明显少于常规组,差异有统计学意义(P0.05)。结论:动态监测血清PCT水平在优化全身性感染患者抗菌治疗策略中具有重要价值。