Microbiological surveillance of the surgical intensive care unit in Zagreb--a pivot for guideline-based therapy of severe sepsis

The aim of this retrospective study was to create guidelines for therapy of severe sepsis in surgical intensive care unit (ICU) for unknown causative agent based on antimicrobial susceptibility of causative bacteria. Seventy-four patients with severe sepsis from surgical ICU in 2003.-2005. were included in study. Their clinical and microbiological data were analyzed from the medical records. Antimicrobial susceptibility of the strains isolated from the blood-culture was tested by disk diffusion method according to CLSI (Clinical Laboratory Standard Institution). APACHE II score was used to predict the severity of illness. Statistical significance difference between results was tested by Mann-Whitney test and chi2 test. Important problem remained type of sepsis: mono-agent sepsis presented less therapeutic problem than sepsis caused with two or more agents (mixed sepsis). Methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Acinetobacter baumannii were predominant causative agents in both type of sepsis. There was remarkable increase of A. baumannii prevalence in 2005 compared to 2004 and to 2003. There was also decrease of MRSA prevalence in 2004 and 2005 compared to 2003. P. aeruginosa were the predominant causative agents in 2004. MRSA displayed good susceptibility to vancomycin and linezolide, whereas P. aeruginosa showed excellent susceptibility to ceftazidime and carbapenems. A. baumannii, third predominant causative agent, exhibited excellent susceptibility to ampicillin+ sulbactam and carbapenems. The recommended therapy is empirical and should cover all important pathogens.     

Etiology of nosocomial surgical infections caused by gram-negative bacteria, and profile of their antibiotic resistance

Microbiological monitoring of microbial landscape of gram-negative bacteria--etiological agents of nosocomial surgical infections--was performed as well as their level of antibiotic resistance was studied. Two hundred forty-four strains were isolated. Antimicrobial susceptibility was assessed by the method of serial microdilutions. Spectrum of Gram-negative microorganisms was represented by 3 groups: fermenting (62.7%), nonfermenting (34.8%), and nonidentified microbes (2.5%). Spectrum of gram-negative etiological agents of nosocomial surgical infections was represented mainly by Pseudomonas aeruginosa, Acinetobacter baumanii, Escherichia coli, and Klebsiella. Most active antibacterial drugs against studied strains were carbapenems (imipenem and meropenem).     

Structure--activity study of the antibacterial peptide fallaxin

Fallaxin is a 25-mer antibacterial peptide amide, which was recently isolated from the West Indian mountain chicken frog Leptodactylus fallax. Fallaxin has been shown to inhibit the growth of several Gram-negative bacteria including Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Here, we report a structure-activity study of fallaxin based on 65 analogs, including a complete alanine scan and a full set of N- and C-terminal truncated analogs. The fallaxin analogs were tested for hemolytic activity and antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-intermediate resistant S. aureus, (VISA), methicillin-susceptible S. aureus (MSSA), E. coli, K. pneumoniae, and P. aeruginosa. We identified several analogs, which showed improved antibacterial activity compared to fallaxin. Our best candidate was FA12, which displayed MIC values of 3.12, 25, 25, and 50 muM against E. coli, K. pneumoniae, MSSA, and VISA, respectively. Furthermore, we correlated the antibacterial activity with various structural parameters such as charge, hydrophobicity H, mean hydrophobic moment mu(H), and alpha-helicity. We were able to group the active and inactive analogs according to mean hydrophobicity H and mean hydrophobic moment mu(H). Far-UV CD-spectroscopy experiments on fallaxin and several analogs in buffer, in TFE, and in membrane mimetic environments (small unilamellar vesicles) indicated that a coiled-coil conformation could be an important structural trait for antibacterial activity. This study provides data that support fallaxin analogs as promising lead structures in the development of new antibacterial agents.     

高龄患者血液感染常见革兰阴性杆菌及其耐药性分析

目的分析本院80~100岁高龄患者血液感染常见革兰阴性杆菌的种类及其耐药状况,为本院合理使用抗生素提供依据。方法采用BacT/Alert 3D血培养仪对血液标本进行阳性鉴定;VITEK-2Compact全自动微生物鉴定仪进行鉴定;K-B纸片扩散法对抗菌药物进行敏感性测定;使用WHONET 5.4分析软件分析数据。结果本院高龄患者血液培养阳性标本中共分离出革兰阴性杆菌108株,以肠杆菌科细菌为主,其次为非发酵菌,前者主要为大肠埃希菌52株(48.15%)和肺炎克雷伯菌37株(34.26%),后者主要包括铜绿假单胞菌10株(9.26%)和鲍曼不动杆菌8株(7.41%)。其中大肠埃希菌和肺炎克雷伯菌对亚胺培南的耐药率分别为1.92%和13.51%,两者对氨苄西林、氨苄西林/舒巴坦、头孢唑林、头孢呋辛的耐药率均高于50.00%;铜绿假单胞菌和鲍曼不动杆菌对亚胺培南的耐药率分别为20.00%和25.00%,后者对其他抗菌药物的耐药率均高于前者。结论碳青酶烯类抗生素可作为本院高龄患者常见革兰阴性杆菌所致血液感染的首选药物;但在治疗中应考虑细菌的耐药特点及患者的代谢特点合理选择抗生素。     

Comparative characteristics of the adhesive properties of microorganisms isolated from the urine of children with chronic obstructive pyelonephritis

The adhesive properties of 215 cultures, including 215 Escherichia coli strains, 43 Klebsiella pneumoniae strains and 60 Pseudomonas aeruginosa strains isolated from the urine of 124 children with chronic obstructive pyelonephritis were studied in the direct hemagglutination test simultaneously with those of 30 E. coli strains and 20 K. pneumoniae strains isolated from the feces of 50 healthy children, as well as 60 P. aeruginosa strains isolated from children with parenteral infections of other localization. E. coli and K. pneumoniae strains isolated from the urine of children with chronic obstructive pyelonephritis were found to have D-mannose-resistant hemagglutinins (68% and 37.2%) and a combination of mannose-sensitive and mannose-resistant adhesins (44.6% and 13.3% respectively). P. aeruginosa strains isolated from the urine of urological patients in the postoperative period showed the presence of mannose-resistant hemagglutinins to a greater extent (76.6%) than those isolated from children with parenteral infections of other localization (45%).     

医院内4种主要革兰阴性菌分布及耐药率分析

摘要：目的 分析大连某三甲医院4种主要革兰阴性病原菌的分布及细菌耐药性变迁,为抗菌药物的合理使用提供依据。方法 回顾性分析2012?2015年住院患者中分离的4种革兰阴性菌临床分布及每年的耐药率,利用WHONET 5.6软件进行统计分析。结果 4年分离致病菌28 485株,其中大肠埃希菌2 994株,肺炎克雷伯菌1 375株,鲍曼不动杆菌1 079株,铜绿假单胞菌1 998株,共占分离致病菌总数的26.1%。4种菌对哌拉西林的耐药率最高（37.2%~78.2%）,对头孢哌酮/苏巴坦耐药率最低（6.7%~39.1%）。2012?2015年,大肠埃希菌、肺炎克雷伯菌和铜绿假单胞菌的抗生素耐药率有下降趋势,鲍曼不动杆菌对多数抗生素耐药率都高,且逐年上升。结论 本院4年感染中4种主要革兰阴性菌占主导地位。4种菌对不同抗生素耐药率和变化不同,鲍曼不动杆菌耐药最严重。4种菌对于头孢哌酮/苏巴坦均比较敏感,对哌拉西林耐药严重。在临床治疗中应有针对性加强管理和用药。     

呼吸内科病原菌的分布及耐药情况

目的：对十堰市人民医院2011年呼吸内科病原菌的分布及耐药情况进行研究,为临床合理使用抗菌药物及控制医院感染提供依据。方法：采用临床流行病学调查方法回顾性收集分析2011年1月-2011年12月呼吸内科病原菌分布及主要病原菌耐药率,对分离鉴定出的病原菌选用常用抗生素进行药敏实验,实验采用K-B法按NCCLS标准进行。结果：病原菌以革兰阴性杆菌为主,其中又以肺炎克雷伯菌、大肠埃希菌、铜绿假单胞菌为主,革兰阳性球菌以金黄色葡萄球菌为主。产酶和不产酶肺炎克雷伯菌、大肠埃希菌及金黄色葡萄球菌耐药率有明显差异。铜绿假单胞菌对头孢噻肟、氨曲南耐药率较高。结论：应根据药敏结果合理使用抗生素,以提高治疗效果,减少耐药菌株产生,预防医院内感染。     

Antibiotic sensitivity pattern; experience at University Hospital, Riyadh, Saudi Arabia

Results of sensitivity testing were discussed based on examination of 5192 isolates of the various bacteria isolated from clinical specimens from King Khalid University Hospital in Riyadh, Saudi Arabia. Streptococcus pyogenes and Streptococcus pneumoniae were sensitive to penicillin and erythromycin. The sensitivity pattern of Staphylococcus aureus was also predictable as they were fairly sensitive to both methicillin (98%) and erythromycin (96%). Neisseria gonorrhoeae (27%) showed a high level of resistance to penicillin. The resistance of Haemophilus influenzae to ampicillin and chloramphenicol was low. Brucella species was sensitive to tetracycline and rifampicin; resistance to streptomycin and cotrimoxazole was minimal being 1% and 6% respectively. The resistance of E. coli, Klebsiella species and Proteus species to second and third generation cephalosporins and amikacin was fairly low ranging from 1.3% to 3%. The gentamicin resistance for these organisms was also within the acceptable range (3%-10%). Gentamicin and amikacin resistance for Pseudomonas aeruginosa was low (2-8%). Salmonella typhi was sensitive to ampicillin, cotrimoxazole, and chloramphenicol. Salmonella enteritidis, Shigella species, and enteropathogenic E. coli were highly resistant to various antibiotics. Campylobacter jejuni was sensitive to gentamicin but 6% of isolates were resistant to erythromycin. Ninety six percent of Gram-negative rods except P. aeruginosa isolated from urine of patients having urinary tract infections were sensitive to amoxycillin-clavulanic acid. In addition, P. aeruginosa showed fairly low resistance to norfloxacin which is given orally to treat cystitis caused by this organism.     

Antimicrobial activity and composition of the essential oil of Gontscharovia popovii from Iran

The aerial parts of Gontscharovia popovii (B. Fedtsch. and Gontsch.) Boriss. were collected at full flowering stage. The essential oil was isolated by hydrodistillation and analyzed by a combination of capillary GC and GC-MS. Thirty-one components were identified with the main constituent being carvacrol (71.9%), followed by linalool (5.5%), p-cymene (4.5%) and gamma-terpinene (4.4%). The in vitro antimicrobial activity of the essential oil of G. popovii was studied against seven Gram-positive and Gram-negative bacteria (Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae) and three fungi (Candida albicans, Saccharomyces cerevisiae and Aspergillus niger). The results of the bioassays showed that the oil exhibited strong antimicrobial activity against all the tested fungi and bacteria except for the resistant bacterium Pseudomonas aeruginosa.     

普外科切口感染病原菌及细菌耐药性分析

目的探讨普外科切口感染菌分布及耐药性,指导临床用药及预防控制措施。方法总结分析本院2003年1月至2005年5月普外科124例切口感染住院患者的病原菌资料。结果124例切口感染标本中共分离出感染菌127株,病原菌依次为:大肠埃希菌占47.24%、肠球菌占18.90%、金黄色葡萄球菌占12.60%、肠杆菌属占7.87%、真菌占7.09%、克雷伯菌属占6.30%。以革兰阴性菌为主占61.41%,革兰阳性菌占31.50%,真菌占7.09%。大肠埃希菌与克雷伯菌的耐药性相仿,对哌拉西林/他唑巴坦、头孢西丁、头孢吡肟、亚胺硫霉素、阿米卡星的耐药率较低,肠杆菌属仅对亚胺硫霉素和阿米卡星的耐药率低,肠球菌仅对万古霉素的耐药率低,金黄色葡萄球菌MRSA检出率为25%,除对青霉素和氨苄青霉素的耐药率较高外,对其它抗菌药物的耐药率尚处于低水平。结论细菌耐药性是引起术后感染、治愈困难的重要原因之一,加强细菌耐药性监测,采用合理预防控制措施,能减低术后切口感染的发生。     

神经外科重症监护病房常见病原菌及耐药性分析

目的:了解神经外科重症监护病房(NICU)常见病原菌及其耐药情况,为临床抗菌药物合理使用提供理论依据。方法:收集2009年1月-2010年12月NICU收治患者的各种标本,对病原菌的分布情况及其对抗菌药物的耐药情况进行回顾性分析。结果:分离出病原菌537株,其中革兰氏阴性菌239株(占68.72%),革兰氏阳性菌139株(占25.88%),真菌29株(占5.40%);前5位病原菌依次为鲍曼不动杆菌(19.93%)、肺炎克雷伯菌(18.44%)、金黄色葡萄球菌(12.29%)、铜绿假单胞菌(7.82%)、大肠埃希氏菌(5.77%);产超广谱β-内酰胺酶(ESBLs)肺炎克雷伯菌和大肠埃希氏菌分离率分别为37.37%、64.52%;耐甲氧西林金黄色葡萄球菌(MRSA)分离率和耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)分离率分别为63.08%、87.50%。结论:NICU病原菌以革兰氏阴性菌为主,对常用抗菌药物的耐药性高。需持续进行细菌流行病学及耐药性监测,指导临床合理使用抗菌药物,减少细菌耐药性产生。     

Validation of AKACID plus as a room disinfectant in the hospital setting

AKACID Plus, a novel polymeric guanidine with broad antimicrobial activity against multiantibiotic-resistant bacterial strains, was used in the present study as a room disinfectant. Disinfection of closed rooms experimentally contaminated with antibiotic-susceptible and multiresistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Escherichia coli was performed using AKACID Plus at concentrations of 0.1, 0.25, and 0.5% for 100 min. Bacterial suspensions were distributed on plastic and stainless steel plates and placed in a test room. Recovery of the test microorganisms was determined before nebulizing, 60 and 100 min after initiation, and 4 h after the end of room disinfection by a simple swab-rinse technique. The swab-rinse method demonstrated a dose- and time-dependent effectiveness of AKACID Plus in eradicating S. aureus, E. coli, and P. aeruginosa on plastic and stainless steel plates. Nebulized 0.5% AKACID Plus was successful in eliminating all hospital pathogens within 340 min. After the use of 0.25% AKACID Plus, MRSA was still detectable on microbial carrier plates. The test concentration of 0.1% AKACID Plus achieved a significant reduction of S. aureus and P. aeruginosa on plastic and stainless steel plates but was sufficient to eradicate only E. coli. These results suggest that nebulized AKACID Plus at a concentration of 0.5% is a potent substance for eradication of pathogenic organisms in the hospital setting.     

Characteristics of gram-negative microflora on environmental objects in puerperal wards and their resistance to antibacterial preparations and disinfectants

The species composition of gram-negative opportunistic bacteria isolated from different objects at three puerperal wards of a maternity clinic was studied. Escherichia coli and Acinetobacter were found to have a fairly wide circulation. The objects most contaminated by these bacteria were determined. The study showed that up to 33.3% of the isolated hospital strains of gram-negative bacteria were characterized by multiple resistance to antibiotics used in medical practice and to sulfathiazole. The strains showed the highest sensitivity to gentamicin and kanamycin. Most of the hospital strains were sensitive to chloramine and nirtan, but 4-13% of Klebsiella and Pseudomonas aeruginosa strains showed enhanced resistance to 0.1% chloramine solution.     

泌尿系感染病原菌分布及耐药性分析

目的了解深圳市人民医院泌尿系感染病原菌的分布及耐药性,为临床医师合理使用抗菌药物提供科学依据。方法对655株泌尿系统感染病原菌进行常规鉴定,用k-B法或ATB-FUNGUS 3对其进行药敏试验。结果病原菌构成比前5位分别为大肠埃希菌（37.9%）、假丝酵母（18.0%）、肠球菌（13.1%）、肺炎克雷伯菌（6.6%）、铜绿假单胞菌（6.3%）。病原菌对各种抗菌药物产生了不同程度的耐药,肺炎克雷伯菌、铜绿假单胞菌对亚胺培南和美罗培南的耐药率为14.3%～26.8%。结论深圳市人民医院泌尿系感染病原菌主要以大肠埃希菌、假丝酵母和肠球菌等为主,病原菌对抗菌药物已产生了一定的耐药性,应加强监测与控制。     

某院感染科病房住院患者常见病原菌分布及 耐药性分析

目的对感染科病房住院患者临床常见病原菌的分布及其耐药性进行分析,为临床预防和治疗感染性疾病提供依据。方法回顾性分析中国医科大学附属第一医院感染科病房2012年1月至2016年12月从住院患者体液及组织样本中分离的病原菌,对其耐药情况进行分析。结果 5年中感染科共分离出非重复病原菌1 266株,其中革兰阴性菌786株,占62.09%,分离率居前3位的是大肠埃希菌、肺炎克雷伯菌以及铜绿假单胞菌,分别占17.22%、15.24%和10.58%;革兰阳性菌共480株,占37.91%,分离率居前3位的是屎肠球菌、草绿色链球菌以及金黄色葡萄球菌,分别占9.79%、7.50%和6.00%。产超广谱β-内酰胺酶(ESBLs)大肠埃希菌和肺炎克雷伯菌检出率分别为66.7%和28.8%。大肠埃希菌对亚胺培南和美罗培南的耐药率分别为0.95%和3.79%,肺炎克雷伯菌对亚胺培南和美罗培南的耐药率分别为2.80%和2.80%。结论我院感染科病房住院患者感染病原菌以革兰阴性菌为主,为有效地控制和避免耐药菌感染的发生,临床应根据药敏试验结果合理应用抗菌药物。     

Purification and properties of antimicrobial peptides from skin secretions of the Eritrea clawed frog Xenopus clivii (Pipidae)

Five peptides with antimicrobial activity were isolated from norepinephrine-stimulated skin secretions of the tetraploid frog Xenopus clivii Peracca, 1898 (Pipidae). Characterization of the peptides demonstrated that they are structurally similar to magainins (2 peptides), caerulein-precursor fragments, CPF (2 peptides), and xenopsin-precursor fragments, XPF (1 peptide) that have been previously isolated from other species of the genus Xenopus. The magainins and the XPF peptide were active only against the Gram-negative microorganism Escherichia coli whereas the CPF peptides were also active against the Gram-positive Staphylococcus aureus. The most abundant antimicrobial peptide in the secretions, CPF-C1 (GFGSLLGKALRLG ANVL.NH(2)) inhibited the growth of the Gram-negative bacteria Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa (MIC≤25μM) suggesting potential for development into an anti-infective agent for use against these emerging antibiotic-resistant pathogens.     

Diagnostic value of a novel nutrient medium for isolation and cultivation of pathogens causing enteric yersiniosis and pseudotuberculosis

A new nutrient medium for isolation and cultivation of the causative agents of enteric yersiniosis and pseudotuberculosis was found to have advantages over Endo medium in its differentiating and inhibiting properties. This medium permitted the easy differentiation of Yersinia pseudotuberculosis from Y. enterocolitica, as well as from Escherichia coli, Shigella flexneri, Klebsiella pneumoniae, K. rhinoscleromatis, Hafnia, Enterobacter and Citrobacter by color; from Proteus inconstans by swarming. In addition, weakly swarming of P. vulgaris differed by their light bluish color and Pseudomonas aeruginosa, by the brilliance and size of colonies. Endo medium could be used only for differentiation of E. coli from lactose-negative Yersinia colonies, Klebsiella (by mucous growth) and, to a certain extent, all Proteus species (by swarming). The medium under test and the control medium inhibited the growth of Staphylococcus aureus. In contrast to Endo medium, the medium under test partially inhibited the growth of K. rhinoscleromatis and the swarming of P. inconstans. The new medium is now introduced into practice.     

Antilactoferrin activity of microorganisms

The detection rate of the antilactoferrin sign and the level of its manifestation in 165 strains of different microbial species, isolated from patients with inflammatory diseases and intestinal dysbacteriosis, were analyzed. The detection rate of antilactoferrin activity was 43 - 90% for Escherichia coli strains, 20 - 86% for Staphylococcus aureus, 60 - 100% for Klebsiella pneumoniae, 76 - 78% for Candida albicans, isolated from different biotopes of man. Most frequently and with high levels of manifestation this sign was registered in strains isolated from the reproductive tract of women. The detection rate of this sign and the level of its manifestation in bacteria of the vaginal and cervical microbiocenosis, isolated from patients, were higher in comparison with healthy persons. The inverse dependence between the level of the antilactoferrin activity of microflora and the content of lactoferrin during the inflammatory process in women was established.     

Antimicrobial susceptibility and molecular mechanisms of resistance to beta-lactams of gram-negative microorganisms--causative agents of nosocomial infections

Profiles and mechanisms of resistance to beta-lactam antibiotics of isolates of Gram-negative microorganisms, which are causative agents of infections in Intensive Care Unit of hospital surgery department, were studied. Two hundred and ten clinical isolates were studied: Pseudomonas aeruginosa--86 strains (40.9%), Acinetobacter baummanii--45 strains (21.4%), Klebsiella pneumoniae--52 strains (24.8%), Escherichia coli--23 strains (11%), Enterobacter spp.--4 strains (1.9%). Profiles of antibiotic resistance were studied by the method of serial microdilutions; detection of most widespread and clinically significant genes of beta-lactamases of Gram-negative bacteria was performed by polymerase chain reaction. Carbapenems and cefoperazone/sulbactam were the most active antibiotics. Local features of distribution of beta-lactamase coding genes (TEM, SHV, CTX) in K. pneumoniae and E. coli isolates were revealed. Eleven strains of P. aeruginosa resistant to carbapenems and possessing genetic determinants of VIM-group, which codes metallo-beta-lactamases, were isolated. Obtained data allows to assess the parameters of resistance to beta-lactam antibiotics and to reveal the main mechanisms of such resistance in etiologic agents of nosocomial infections, that, in its turn, allows to choose preparations for etiotropic therapy.     

Screening of some plants from Northern Argentina for their antimicrobial activity

AIMS: Screening of antimicrobial activity in 25 plant species from Northern Argentina. METHODS AND RESULTS: Inhibition of microbial growth was measured by a microplate assay with an oxidation-reduction indicator (Alamar Blue). Test organisms were: Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus and Enterococcus faecium. Weak inhibitory activities (MIC=0.5 mg dry matter ml(-1)) were found in methanolic extracts of Rivina humilis, Crateva tapia, Funastrum claucum and Schinopsis balansae. Stronger bacteriostatic power was detected in Vassobia breviflora (MIC=0.25 mg ml(-1) against Staphylococcus aureus, and 0.5 mg ml(-1) against Enterococcus faecium). This activity was purified five-fold by extraction with dichloromethane, and it was found equally effective against susceptible or antibiotic-resistant strains of Staph. aureus. In addition, the purified extract was synergistic with gentamicin, and it was bactericidal at 24 h, with a concentration of 0.25 mg ml(-1). CONCLUSION: There is a significant antimicrobial activity in Vassobia breviflora. SIGNIFICANCE AND IMPACT OF THE STUDY: Further studies will be required to disclose the potential importance of these findings.