Current clinical status on the preventive effects of cranberry consumption against urinary tract infections

Urinary tract infections (UTIs) represent a common and quite costly medical problem, primarily affecting the female population which may be due to a shorter urethra. The bacterium Escherichia coli are mainly responsible for most uncomplicated UTIs. Cranberry antibacterial effects have widely been studied in vitro, and laboratory and clinical studies have also been performed to elucidate the mechanisms of cranberry actions and the clinical benefits of cranberry consumption against UTIs. The present review aimed to summarize the proposed mechanisms of cranberry actions against UTIs and the clinical trials that evaluated the efficacy of supplementing cranberry products in different subpopulations. Taking into consideration the existing data, cranberry consumption may prevent bacterial adherence to uroepithelial cells which reduces the development of UTI. Cranberry consumption could also decreasing UTI related symptoms by suppressing inflammatory cascades as an immunologic response to bacteria invasion. The existing clinical trials suggest that the beneficial effects of cranberry against UTIs seem to be prophylactic by preventing the development of infections; however, they exert low effectiveness in populations at increased risk for contracting UTIs. Additional well-designed, double-blind, placebo-controlled clinical trials that use standardized cranberry products are strongly justified in order to determine the efficiency of cranberry on the prevention of UTIs in susceptible populations.     

A Review of Nonantibiotic Agents to Prevent Urinary Tract Infections in Older Women

ObjectiveThis article provides a comprehensive literature review on nonantibiotic agents used for the prevention of urinary tract infections (UTIs) in women ≥45 years of age.DesignA structured review was performed by conducting a literature search to identify relevant studies pertaining to the use of nonantibiotic agents to prevent UTIs in women who were perimenopausal through postmenopausal. Recommendations were made for or against the use of each nonantibiotic agent, unless data were unavailable. Levels of evidence were assigned to each recommendation made.Setting and participantsStudies on the prevention of UTIs with women subjects ≥45 years of age in the community, inpatient, and long-term care settings were considered for inclusion.MeasureThe efficacy and safety of using ascorbic acid, cranberry products, d-mannose, estrogens, lactobacilli, and methenamine hippurate for prevention of UTIs was assessed.ResultsThere is evidence to support use of estrogens (A-I) in postmenopausal women, and cranberry capsules (C-I) in women ≥45 years of age for the prevention of UTIs. There was a lack of evidence to make recommendations for or against the use of ascorbic acid, cranberry juice, cranberry capsules with high proanthocyanidin (PAC) content, d-mannose, lactobacillus, and methenamine hippurate in this population.Conclusions/ImplicationsCurrent studies support that estrogens and cranberry capsules may have a role in preventing UTIs in women ≥45 years of age. Further research is needed to elucidate the role of these nonantibiotic agents and how they may be used to decrease antibiotic use.     

Escherichia coli biofilm formation and dispersion under hydrodynamic conditions on metal surfaces

The aim of this study was to analyze the impact of hydrodynamic forces on the multiplication of E. coli, and biofilm formation and dispersion. The experiments were provided in a flow chamber simulating a cleaning-in-place system. Biofilm biomass was measured using a crystal violet dye method. The results show that hydrodynamic forces affect not only biofilm formation and dispersion but the multiplication of E. coli in the first place. We found more biofilm biomass on the rough surface than on the smooth one. The results of the biofilm formation test show that laminar flow promotes the biofilm growth over 72 h, meanwhile turbulent flow after 48 h causes decrease in biomass. The results of the biofilm dispersion test, in contrast, show that laminar flow removed less biofilm from both materials that turbulent flow did. Therefore, taking into account these findings in cleaning-in-place technology can substantially reduce E. coli multiplication and biofilm formation.     

粪肠球菌临床株对泰利唑胺体外抗菌活性的研究

目的评价泰利唑胺体外抗粪肠球菌的活性,探讨泰利唑胺不敏感粪肠球菌的耐药机制及其多位点序列分型分布情况。方法收集2011年1月1日—2016年6月30日深圳市南山区人民医院临床分离的粪肠球菌菌株,使用自动化仪器法及微量肉汤稀释法对分离菌株的耐药性进行检测。应用聚合酶链式反应(PCR)方法检测恶唑烷酮类抗生素耐药基因的携带情况,并采用多位点序列分型(MLST)对分离菌株进行分型。结果共获得289株粪肠球菌,来源科室主要为外科(57.4%),标本来源主要为中段尿(126株,43.6%)。289株粪肠球菌对泰利唑胺敏感率为94.1%,对氨苄西林、呋喃西林和万古霉素有较高的敏感性(敏感率为97.9%～99.7%)。MLST结果显示,共分为47个ST型,优势ST分型为ST16和ST179,分别占29.1%(84株)和24.9%(72株),在泰利唑胺不敏感粪肠球菌中,ST16的比例高于ST179(P0.05)。共检出泰利唑胺不敏感粪肠球菌17株,其携带optrA基因比例高于敏感株。结论泰利唑胺对粪肠球菌的抗菌活性整体优于利奈唑胺,但对携带optrA基因的粪肠球菌则未显示出良好的抗菌活性。     

Efficacy of sodium dodecyl sulphate and natural extracts against E. coli biofilm

The aim of this study was to determine and compare the efficacy of a standard cleaning agent, sodium dodecyl sulphate, and natural extracts from pomegranate peel grape skin and bay laurel leaf against E. coli biofilm. The biofilm was exposed for 10 minutes to three different concentrations of each tested compound. The results show that bay laurel leaf extract is the most efficient with 43% biofilm biomass reduction, followed by pomegranate peel extract (35%); sodium dodecyl sulphate and grape skin extract each have 30% efficacy. Our study demonstrated that natural extracts from selected plants have the same or even better efficacy against E. coli biofilm removal from surfaces than the tested classical cleaning agent do. All this indicates that natural plant extracts, which are acceptable from the health and environment points of view, can be potential substitutes for classical cleaning agents.     

Inhibition of adhesion of uropathogenic Escherichia coli bacteria to uroepithelial cells by extracts from cranberry

Cranberry extract has been reported as a therapeutic agent, mainly in urinary tract infections due to its anti-adhesive capacity. In order to compare the effects of proanthocyanidin (procyanidin) (PAC)-standardized cranberry extracts and commercial PAC A2, we first investigated the presence of genes encoding known adhesins on 13 strains of uropathogenic strains coming from patients with cystisis. After this characterization, the anti-adhesive effects of PAC A2 were assayed on selected uropathogenic Escherichia coli strains before testing cranberry extracts. Before checking inhibitory effect on bacterial adhesion to cells, we showed that neither PAC A2 or three cranberry extracts (A, B, and C) specifically inhibited the growth and did not supply any potential nutrient to E. coli strains, including the unrelated control strain. PAC A2 exhibited an inhibitory effect on the adhesion of two selected uropathogenic strains of E. coli. This work also showed that a preliminary exposure of bacteria to PAC A2 significantly reduced the adhesion. This phenomenon has been also observed with a lesser impact when uroepithelial cells were pretreated with PAC A2. Moreover, the assays were more robust when bacteria were in fast growing conditions (exponential phase): the adhesion to uroepithelial cells was greater. Significant reduction of adhesion to urepithelial cells was observed: around 80% of inhibition of adhesion with the cranberry extracts at equivalent PAC concentration of 50?μg/mL. The effects of the different assayed extracts were not obviously different except for extract B, which inhibited approximately 55% of adhesion at an equivalent PAC concentration of 5?μg/mL.     

Antibiotic Resistance Pattern of Community Acquired Uropathogens at a Tertiary Care Hospital in Jaipur, Rajasthan

Background:

Urinary tract infections (UTIs) are amongst the most common infections described in outpatients setting.

Objectives:

A study was conducted to evaluate the uropathogenic bacterial flora and its antimicrobial susceptibility profile among patients presenting to the out-patient clinics of a tertiary care hospital at Jaipur, Rajasthan.

Materials and Methods:

2012 consecutive urine specimens from symptomatic UTI cases attending to the outpatient clinics were processed in the Microbiology lab. Bacterial isolates obtained were identified using biochemical reactions. Antimicrobial susceptibility testing was performed by the Kirby-Bauer disc diffusion method. Extended spectrum beta lactamase (ESBL) production was determined by the double disk approximation test and the Clinical and Laboratory Standards Institute (formerly NCCLS) confirmatory method.

Results:

Pathogens were isolated from 346 (17.16%) of the 2012 patients who submitted a urine sample. Escherichia coli was the most frequently isolated community acquired uropathogen accounting for 61.84% of the total isolates. ESBL production was observed in 23.83% of E. coli strains and 8.69% of Klebsiella strains. With the exception of Nitrofurantoin, resistance to agents commonly used as empiric oral treatments for UTI was quite high.

Conclusion:

The study revealed E. coli as the predominant bacterial pathogen for the community acquired UTIs in Jaipur, Rajasthan. An increasing trend in the production ESBLs among UTI pathogens in the community was noted. Nitrofurantoin should be used as empirical therapy for primary, uncomplicated UTIs.     

Recurrent urinary tract infections in children: Preventive interventions other than prophylactic antibiotics

Urinary tract infection (UTI) is one of the most common childhood infections. Permanent renal cortical scarring may occur in affected children, especially with recurrent UTIs, leading to long-term complications such as hypertension and chronic renal failure. To prevent such damage, several interventions to prevent UTI recurrences have been tried. The most established and accepted prevention at present is low dose long-term antibiotic prophylaxis. However it has a risk of break through infections, adverse drug reactions and also the risk of developing antibiotic resistance. The search is therefore on-going to find a safer, effective and acceptable alternative. A recent meta-analysis did not support routine circumcision for normal boys with no risk factors. Vaccinium Macrocarpon (cranberry), commonly used against UTI in adult women, is also effective in reducing the number of recurrences and related antimicrobial use in children. Sodium pentosanpolysulfate, which prevents bacterial adherence to the uroepithelial cells in animal models, has shown conflicting results in human trials. When combined with antibiotic, Lactobacillus acidophilus (LA-5) and Bifidobacterium, by blocking the in vitro attachment of uropathogenic bacteria to uroepithelial cells, significantly reduce in the incidence of febrile UTIs. Deliberate colonization of the human urinary tract of patients with recurrent UTI with Escherichia-coli (E. coli) 83972 has resulted in subjective benefit and less UTI requiring treatment. The non-pathogenic E. coli isolate NU14 DeltawaaL is a candidate to develop live-attenuated vaccine for the treatment and prevention of acute and recurrent UTI. Diagnosing and treating dysfunctional elimination syndromes decrease the incidence of recurrent UTI. A meta-analysis found the lack of robust prospective randomized controlled trials limited the strength of the established guidelines for surgical management of vesicoureteral reflux. In conclusion, several interventions, other than antibiotic prophylaxis, for the prevention of recurrent UTI have been tried and, although showing some promise, they do not provide so far a definitive effective answer. Finding suitable alternatives still requires further high quality research of those seemingly promising interventions.     

产志贺样毒素且具侵袭力的大肠杆菌的研究

我国临床腹泻病人粪便标本中，约有６０％检不出任何已知病原，而能分离出几乎纯培养的大肠杆菌。这些大肠杆菌过去被误认为是肠道正常菌样，我们对在北京西城区三个医院从腹泻病患者粪便本本中分离的１７２株所谓正肠杆菌，进行质粒ＤＮＡ，Ｈｅｐ－２细胞粘附试验，和１０种ＤＮＡ探针分析，结果表发现这些所谓的肠道正常大肠杆菌并不正常，其中４４％可为致泻性大肠杆菌，包括ＥＨＥＣ１６株，占所检查菌株的９．３％；ＥＰＥＣ８     

O26:H11及NM大肠埃希菌CRISPR的分子分布特征及其与stx噬菌体的关系

目的 探讨O26：H11及NM血清型大肠埃希菌中成簇规律间隔短回文重复序列（CRISPR）的分子分布特征及其与stx噬菌体的关系。方法 135株O26：H11及NM血清型大肠埃希菌从NCBI数据库获取,利用CRT软件及CRISPR Finder提取CRISPR信息,并用Excel软件对间隔序列进行编号及分析CRISPR亚型,并分析CRISPR与stx噬菌体之间的关系。结果 135株O26：H11及NM血清型大肠埃希菌中均存在CRISPR结构,CRISPR1包括19个亚型,CRISPR 2.1包括22个亚型,CRISPR2.2包括1个亚型,CRISPR3-4包括1个亚型。stx噬菌体在CRISPR群组C中出现,stx⁺ 菌株比stx^-菌株拥有更多的间隔序列。结论 CRISPR位点在O26：H11或NM血清型大肠埃希菌中广泛存在,且存在着不同的亚型,stx噬菌体与CRISPR的分子分布特征有关,可能作为鉴定高毒菌株的分子靶标。     

Consumption of cranberry beverage improved endogenous antioxidant status and protected against bacteria adhesion in healthy humans: a randomized controlled trial

Consumption of polyphenol-rich foods is associated with lower risk from many chronic diseases. We hypothesized that a single dose of cranberry beverage would improve indices of oxidative stress, inflammation, and urinary antibacterial adhesion activity in healthy humans. Six males and 6 females (18-35 years; body mass index, 19-25 kg/m²) consumed placebo, cranberry leaf extract beverage, or low-calorie cranberry juice cocktail (LCJC) once in a randomized, double-blind, placebo-controlled cross-over experimental design trial. The washout period between beverages was 1 week. Blood was collected 0, 2, 4, 8, and 24 hours after beverage consumption for measuring oxidative and inflammatory biomarkers. Urine was collected at 0, 0 to 3, 3 to 6, 6 to 9, 9 to 12, and 24 hours postintervention to assess antibacterial adhesion activity. Consumption of cranberry leaf extract beverage elevated (P < .05) blood glutathione peroxidase activity, whereas LCJC consumption increased (P < .05) glutathione concentrations and superoxide dismutase activity compared with placebo. Cranberry leaf extract beverage and LCJC consumption had no effect on the inflammatory biomarkers measured as compared with placebo. At 0 to 3 hours postconsumption, urine from participants who consumed cranberry beverages had higher (P < .05) ex vivo antiadhesion activity against P-fimbriated Escherichia coli compared with placebo. An acute dose of cranberry beverages improved biomarkers of antioxidant status and inhibition of bacterial adhesion in urine.     

Sewage sludge and liquid pig manure as possible sources of antibiotic resistant bacteria

Within the last decades, the environmental spread of antibiotic resistant bacteria has become a topic of concern. In this study, liquid pig manure (n=305) and sewage sludge (n=111) - used as agricultural fertilizers between 2002 and 2005 - were investigated for the presence of Escherichia coli, Enterococcus faecalis and Enterococcus faecium. Bacteria were tested for their resistance against 40 chemotherapeutics including several “reserve drugs”. E. coli (n=613) from pig manure were at a significantly higher degree resistant to streptomycin, doxycycline, spectinomycin, cotrimoxazole, and chloramphenicol than E. coli (n=116) from sewage sludge. Enterococci (Ent. faecalis, n=387, and Ent. faecium, n=183) from pig manure were significantly more often resistant to high levels of doxycycline, rifampicin, erythromycin, and streptomycin than Ent. faecalis (n=44) and Ent. faecium (n=125) from sewage sludge. Significant differences in enterococcal resistance were also seen for tylosin, chloramphenicol, gentamicin high level, fosfomycin, clindamicin, enrofloxacin, moxifloxacin, nitrofurantoin, and quinupristin/dalfopristin. By contrast, aminopenicillins were more effective in enterococci from pig manure, and mean MIC-values of piperacillin+tazobactam and third generation cefalosporines were significantly lower in E. coli from pig manure than in E. coli from sewage sludge. 13.4% (E. coli) to 25.3% (Ent. faecium) of pig manure isolates were high-level multiresistant to substances from more than three different classes of antimicrobial agents. In sewage sludge, high-level-multiresistance reached from 0% (Ent. faecalis) to 16% (Ent. faecium). High rates of (multi-) resistant bacteria in pig manure emphasize the need for a prudent - cautious - use of antibiotics in farm animals.     

中南大学湘雅医院2013—2017年细菌耐药性监测

 目的 了解中南大学湘雅医院2013—2017年临床分离细菌的分布以及对常用抗菌药物的敏感性,为临床合理使用抗菌药物提供依据。方法 收集门诊和住院患者培养标本分离的菌株,采用标准纸片扩散法或自动化仪器检测法进行药敏试验,对细菌耐药监测数据进行统计分析。结果 共分离38 075株细菌,其中革兰阳性菌13 184株,占34.6%,革兰阴性菌24 891株,占65.4%。居前五位的细菌分别是大肠埃希菌（5 158株,13.5%）、不动杆菌属（4 740株,12.4%）、克雷伯菌属（4 470株,11.7%）、凝固酶阴性葡萄球菌（4 008株,10.5%）、铜绿假单胞菌（3 577株,9.4%）。耐甲氧西林金黄色葡萄球菌（MRSA）和耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）的检出率分别为31.7%（980/3 096）和77.7%（3 113/4 008）,MRSA的检出率呈下降趋势（P<0.01）;葡萄球菌对绝大多数抗菌药物的耐药率耐甲氧西林株高于甲氧西林敏感株;未检测出耐万古霉素的葡萄球菌属细菌以及耐利奈唑胺的金黄色葡萄球菌。屎肠球菌对青霉素、氨苄西林、高浓度庆大霉素、高浓度链霉素、红霉素、呋喃妥因、氟喹诺酮类抗菌药物的耐药率高于粪肠球菌（均P<0.01）,粪肠球菌和屎肠球菌对万古霉素和利奈唑胺的耐药率<3.5%。未检测出耐利奈唑胺和万古霉素的链球菌属细菌。大肠埃希菌、肺炎克雷伯菌对碳青霉烯类抗生素的耐药率分别为0.6%~3.9%、6.3%~24.9%。铜绿假单胞菌、鲍曼不动杆菌对亚胺培南的耐药率分别为29.5%~34.7%、69.9%~85.7%。大肠埃希菌、肺炎克雷伯菌和鲍曼不动杆菌对碳青霉烯类抗生素的耐药率呈逐年上升趋势（均P<0.01）。结论 鲍曼不动杆菌对碳青霉烯类抗生素的耐药率较高,肺炎克雷伯菌对碳青霉烯类抗生素的耐药率迅速上升。应加强抗菌药物的合理使用,采取有效的医院感染控制措施,减少耐药菌的产生及传播。     

Synthesis, structure and structure–activity relationship analysis of 3-tert-butoxycarbonyl-2-arylthiazolidine-4-carboxylic acid derivatives as potential antibacterial agents

Nine 2-arylthiazolidine-4-carboxylic acid derivatives and nine 3-tert-butoxycarbonyl-2-arylthiazolidine-4-carboxylic acid derivatives were synthesized to screen for their antibacterial activities. Compounds 5, 14–18 were first reported. Their chemical structures were clearly determined by ¹H NMR, ¹³C NMR, ESI mass spectra and elemental analyses, coupled with one selected single-crystal structure. All the compounds were assayed for antibacterial activities against two Gram-positive bacterial strains (Bacillus subtilis ATCC 6633 and Staphylococcus aureus ATCC 6538) and two Gram-negative bacterial strains (Escherichia coli ATCC 35218 and Pseudomonas aeruginosa ATCC 13525) by MTT method. Most of the 3-tert-butoxycarbonyl-2-arylthiazolidine-4-carboxylic acid derivatives exhibited better antibacterial activities against the four bacterial strains than relative 2-arylthiazolidine-4-carboxylic acid derivatives. Compound (2RS,4R)-3-(tert-butoxycarbonyl)-2-(5-fluoro-2-hydroxyphenyl)thiazolidine-4-carboxylic acid (14) showed powerful antibacterial activities against P. aeruginosa with IC₅₀ value of 0.195 μg/mL, which was superior to the positive controls Penicillin G and Kanamycin B, respectively. On the basis of the biological results, structure–activity relationships were discussed.     

无锡市某院老年男性患者尿路感染病原菌分布及耐药性

 

目的 了解老年男性患者尿标本病原菌分布及耐药性,为其感染治疗提供参考。方法 选取2012年1月-2016年12月于无锡市人民医院门诊就诊及住院的老年男性尿路感染患者为研究对象,分析其尿路感染病原菌分布及耐药性。结果 共收集尿路感染病原菌2 745株,标本阳性率较高的科室是重症监护病房（ICU）、泌尿外科、内分泌科,分别为52.75%、48.70%和43.63%。其中革兰阴性（G^-）菌1 377株（50.16%）,革兰阳性（G⁺）菌814株（29.65%）,真菌554株（20.19%）。检出菌株数居前5位的依次是大肠埃希菌（487株,17.74%）、屎肠球菌（256株,9.33%）、铜绿假单胞菌（253株,9.22%）、白假丝酵母菌（250株,9.11%）及粪肠球菌（216株,7.87%）。泌尿外科检出大肠埃希菌（115株,23.52%）、铜绿假单胞菌（88株,35.06%）和粪肠球菌（77株,35.65%）最多,ICU检出屎肠球菌（38株,14.84%）和白假丝酵母菌（83株,33.20%）最多。大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌对亚胺培南的耐药率分别为1.23%、5.59%、15.02%;大肠埃希菌对哌拉西林/他唑巴坦、阿米卡星、呋喃妥因的耐药率分别为3.49%、6.16%、8.62%;肺炎克雷伯菌对头孢吡肟、头孢他啶、哌拉西林/他唑巴坦的耐药率分别为23.78%、16.78%、12.59%。屎肠球菌对万古霉素、利奈唑胺的耐药率分别为4.30%、4.69%;粪肠球菌对万古霉素、利奈唑胺、氨苄西林的耐药率分别为0.46%、2.78%、3.24%。共检出耐碳青霉烯类铜绿假单胞菌38株,检出菌株数呈逐年上升趋势。结论 该院老年男性患者尿路感染的主要病原菌为大肠埃希菌,其对亚胺培南、哌拉西林/他唑巴坦、阿米卡星及呋喃妥因较敏感。老年男性患者尿路感染居前五位病原菌科室分布存在差异,临床经验治疗应参考老年男性尿路感染病原菌的科室分布及耐药特点,从而针对性选用抗菌药物。

     

Prevalence of virulence determinants and antibiotic resistance patterns of Enterococcus faecalis strains in patients with community-acquired urinary tract infections in Iran

The aim of this study was to characterize virulence factors and antibiotic resistance patterns in E. faecalis strains obtained from community-acquired urinary tract infections. A total of 70 E. faecalis isolates from Labbafinejad Hospital in Tehran were collected. Antibiotic resistance and virulence determinants were examined by phenotypic and molecular methods.

Among 70 E. faecalis isolates, efba (97.1%), ace (95.7%), and gelE (94.3%) were the most prevalent virulence genes. The most common antibiotic resistance pattern was tetracycline (88.6%) and minocycline (87.1%). Multi-drug resistant phenotype was detected among 10% of them.

Our results showed capability of E. faecalis strains for infection of the urinary tract in community. Involvement of virulence determinants in the pathogenesis of community acquired E. faecalis strains was proposed due to their high prevalence rates. Food producing animals were proposed as their environmental reservoirs, due to dominance of tetracycline resistance phenotype among them.     

Synthesis and evaluation of in vitro anti-microbial and anti-tubercular activity of 2-styryl benzimidazoles

A new series of novel 5-(nitro/bromo)-styryl-2-benzimidazoles (1–12) has been synthesized by simple, mild and efficient synthetic protocol by attempted condensation of 5-(nitro/bromo)-o-phenylenediamine with trans-cinnamic acids in ethylene glycol. Screening for in vitro anti-tubercular activity against Mycobacterium tuberculosis H₃₇ Rv, anti-bacterial activity against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae bacterial strains and anti-fungal activity against Candida albicans and Asperigillus fumigatus fungal strains were carried out. Compounds 5, 7, 8, 9, 11 showed higher anti-tubercular activity and compounds 7, 8, 10, 11, 12 have proved to be effective with MIC (μg/ml) and emerged as lead molecules showing excellent activities against a panel of microorganisms. All synthesized compounds were characterized using IR, ¹H, ¹³C NMR, GC–MS and elemental analysis.     

全国细菌耐药监测网2014-2019年腹腔积液标本细菌耐药监测报告

目的 了解中国腹腔积液标本病原菌分布特点及耐药情况,为临床合理选用抗菌药物提供依据.方法 全部监测数据来源于全国细菌耐药监测网(CARSS)成员单位2014年1月-2019年9月腹腔积液标本中分离获得的菌株,依据保留同一患者相同细菌第一株的原则剔除重复菌株后,纳入最终分析.结果 2014-2019年共检出腹腔积液来源非...     

Comparative in vitro inhibition of urinary tract pathogens by single- and multi-strain probiotics

Purpose

Multi-species probiotic preparations have been suggested as having a wide spectrum of application, although few studies have compared their efficacy with that of individual component strains at equal concentrations. We therefore tested the ability of 4 single probiotics and 4 probiotic mixtures to inhibit the urinary tract pathogens Escherichia coli NCTC 9001 and Enterococcus faecalis NCTC 00775.

Methods

We used an agar spot test to test the ability of viable cells to inhibit pathogens, while a broth inhibition assay was used to assess inhibition by cell-free probiotic supernatants in both pH-neutralised and non-neutralised forms.

Results

In the agar spot test, all probiotic treatments showed inhibition, L. acidophilus was the most inhibitory single strain against E. faecalis, L. fermentum the most inhibitory against E. coli. A commercially available mixture of 14 strains (Bio-Kult^®) was the most effective mixture, against E. faecalis, the 3-lactobacillus mixture the most inhibitory against E. coli. Mixtures were not significantly more inhibitory than single strains. In the broth inhibition assays, all probiotic supernatants inhibited both pathogens when pH was not controlled, with only 2 treatments causing inhibition at a neutral pH.

Conclusions

Both viable cells of probiotics and supernatants of probiotic cultures were able to inhibit growth of two urinary tract pathogens. Probiotic mixtures prevented the growth of urinary tract pathogens but were not significantly more inhibitory than single strains. Probiotics appear to produce metabolites that are inhibitory towards urinary tract pathogens. Probiotics display potential to reduce the incidence of urinary tract infections via inhibition of colonisation.     

上海市2012－2013年4种致泻性大肠埃希菌监测

目的 基于临床医院开展4种致泻性大肠埃希菌(DEC)人群监测,探讨公共卫生实验室对临床实验室需求的直接技术指导的实践模式。方法 设立哨点医院,以标准化方法筛选和鉴定DEC菌型;构建DEC流行特征基线;对疑似暴发病例开展基于实验室和流行病学调查。结果 2012－2013年选择上海地区4家哨点医院检测7 204份腹泻标本确认的712例DEC感染病例,阳性率为9.9%。其中肠致病性大肠埃希菌(EPEC)感染351例;肠产毒性大肠埃希菌(ETEC)感染292例;肠侵袭性大肠埃希菌(EIEC)感染32例;产志贺样毒素大肠埃希菌(STEC/EHEC)感染6例;DEC混合感染31例。EPEC感染以1～5岁儿童最多见,菌型均为aEPEC;ETEC流行峰值在8月,阳性率>20%,感染病例2012年聚集于1～28日龄和2013年的20～60岁人群(P< 0.05),菌型以耐热肠毒素(ST)型最多(59.6%),其次为不耐热肠毒素(LT)型(27.8%)和ST/LT型(12.6%);2013年儿童感染EIEC病例明显增加(P< 0.01);未监测到EHEC O157 : H7,但确认2例EHEC O26 : H11(eae-hlyA-stx1a)儿童病例;调查确认2012年上海地区15例新生儿ETEC聚集性感染病例与四川省自贡市新生儿病例属于同一克隆(STh-CS21-CFA/I-ClyA-EatA-ST2332- SHNL0005)。结论 上海地区DEC型谱特征已发生改变,ETEC对新生儿院内感染和食源性感染性腹泻构成潜在暴发风险,需加强实验室主动监测。