Metabolic Profiling of VOCs Emitted by Bacteria Isolated from Pressure Ulcers and Treated with Different Concentrations of Bio-AgNPs.

Considering the advent of antibiotic resistance, the study of bacterial metabolic behavior stimulated by novel antimicrobial agents becomes a relevant tool to elucidate involved adaptive pathways. Profiling of volatile metabolites was performed to monitor alterations of bacterial metabolism induced by biosynthesized silver nanoparticles (bio-AgNPs). Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae and Proteus mirabilis were isolated from pressure ulcers, and their cultures were prepared in the presence/absence of bio-AgNPs at 12.5, 25 and 50 µg mL-1. Headspace solid phase microextraction associated to gas chromatography-mass spectrometry was the employed analytical platform. At the lower concentration level, the agent promoted positive modulation of products of fermentation routes and bioactive volatiles, indicating an attempt of bacteria to adapt to an ongoing suppression of cellular respiration. Augmented response of aldehydes and other possible products of lipid oxidative cleavage was noticed for increasing levels of bio-AgNPs. The greatest concentration of agent caused a reduction of 44 to 80% in the variety of compounds found in the control samples. Pathway analysis indicated overall inhibition of amino acids and fatty acids routes. The present assessment may provide a deeper understanding of molecular mechanisms of bio-AgNPs and how the metabolic response of bacteria is untangled.

Wound Infections from Taiwan Cobra (Naja atra) Bites: Determining Bacteriology, Antibiotic Susceptibility, and the Use of Antibiotics-A Cobra BITE Study.

Wound necrosis and secondary infection are common complications after Naja atra bites. Clinical tools to evaluate the infection risk after Taiwan cobra bites are lacking. In this Cobra BITE study, we investigated the prevalence of wound infection, bacteriology, and corresponding antibiotic usage in patients presenting with Taiwan cobra snakebites. Patients with wound infection lacking tissue necrosis were included in developing Cobra BITE score utilizing univariate and multiple logistic regression, as patients with wound necrosis require antibiotics for infection treatment. 8,295,497 emergency department visits occurred in the span of this study, with 195 of those patients being diagnosed as having cobra bites. Of these patients, 23 had wound necrosis, and 30 had wound infection, resulting in a wound infection rate of 27.2% (53/195). Enterococcus faecalis and Morganella morganii were the main bacteria identified in the culture report regardless of whether patients' wounds had necrosis. As per our Cobra BITE score, the three factors predicting secondary wound infection after cobra bites are hospital admission, a white blood cell count (in 103/µL) × by neu-trophil-lymphocyte ratio value of ≥114.23, and the use of antivenin medication. The area under the receiver operating characteristic curve for the Cobra BITE score system was 0.88; ideal sensitivity and specificity were 0.89 and 0.76. This scoring system enables the assessment of wound infections after N. atra bites, and it could be modified and improved in the future for other Naja spp. bites.

Development of Chlorhexidine Digluconate and Lippia sidoides Essential Oil Loaded in Microemulsion for Disinfection of Dental Root Canals: Substantivity Profile and Antimicrobial Activity.

The dental intracanal disinfection is crucial to achieve the success of endodontic treatment, avoiding the maintenance of endodontic infections. Chlorhexidine digluconate can act as an irrigating agent for it. However, it can cause tissue irritation in high concentrations. Therefore, combinations with other antimicrobial agents and more efficient therapeutic alternatives are studied, which make it possible to administer drugs more safely and with minimal adverse effects. Thus, the objective of this study was the development of a microemulsion containing chlorhexidine digluconate and essential oil of Lippia sidoides to be used for disinfection of dental root canals and to evaluate its profile of substantivity and antimicrobial activity. The microemulsions were obtained through phase diagrams, using the spontaneous formation method. We completed a physical-chemical characterization and evaluate the stability of the microemulsions, in addition to the substantivity profile in a bovine root dentin model, and in vitro antibacterial effect on Enterococcus faecalis. A method for quantifying chlorhexidine was developed using UV-Vis spectroscopy. The microemulsions showed acid pH, conductivity above 1.3 µScm-1, and dispersion index similar to water. The microemulsions showed antimicrobial inhibition halos similar to the commercial gel conventionally used, but with four times more substantivity to dentinal tissues. Microemulsions were obtained as a therapeutic alternative to formulations available on the market, presenting themselves as a system with great potential for the administration of drugs for disinfection of root canals.

Phages in a thermoreversible sustained-release formulation targeting E. faecalis in vitro and in vivo.

INTRODUCTION: Enterococcus faecalis is a key pathogen recovered from root canals when conventional treatment fails. Phage therapy has generated new interest in combating pathogens. A sustained-release formulation using specific phages against E. faecalis may offer an alternative approach. OBJECTIVES: To evaluate the efficacy of anti-E. faecalis phages formulated in a thermo- sustained-release system against E. faecalis in vitro and in vivo. METHODS: EFDG1 and EFLK1 phages were formulated with poloxamer P407. Gelation time, phage survival, activity and toxicity were evaluated. Lytic activity was evaluated in vitro against E. faecalis at various growth phases, including anti-biofilm activity. Methods included viable bacterial count (CFU/mL), biofilm biomass determination and electron microscopy (live/dead staining). Further evaluation included infected incisors in an in vivo rat model. Anti-E. faecalis phage-cocktail suspension and sustained-release phage formulation were evaluated by viable bacterial count (CFU/mL), histology, scanning electron microscopy (SEM) and 16S genome sequencing of the microbiota of the root canal. RESULTS: Gelation time for clinical use was established. Low toxicity and a high phage survival rate were recorded. Sustained-release phages reduced E. faecalis in logarithmic (4 logs), stationary (3 logs) and biofilm (4 logs) growth phases. Prolonged anti-biofilm activity of 88% and 95% reduction in biomass and viable counts, respectively, was recorded. Reduction of intracanal viable bacterial counts was observed (99% of enterococci) also seen in SEM. Phage treatment increased Proteobacteria and decreased Firmicutes. Histology showed reduced periapical inflammation and improved healing following phage treatment. CONCLUSION: Poloxamer P407 formulated with phages has an effective and long-lasting effect in vitro and in vivo targeting E. faecalis.

Ibuprofen lacks direct antimicrobial properties for the treatment of urinary tract infection isolates.

The high incidence of urinary tract infection (UTI) among women and children, in combination with a lack of antibiotic efficacy with regard to pathogen eradication and recurrence prevention, as well as the negative side effects associated with antibiotics, has led researchers to explore the role of non-steroidal anti-inflammatory drugs as a primary management strategy. The aim of this study was to determine whether ibuprofen (IBU) or one of its major metabolites, 2-carboxyibuprofen (CIBU), could affect the growth and adhesion of the two most common uropathogens, Escherichia coli and Enterococcus faecalis. The bacterial growth and adhesion to the urothelial cells of E. coli UTI89 and E. faecalis 1131 in the presence of physiologically relevant concentrations of IBU and CIBU were assessed. The effect of IBU on bacterial adhesion to urothelial cells was also assessed following exposure to trimethoprim/sulfamethoxazole (TMP/SMX) and nitrofurantoin. Bacterial growth was not affected by IBU. Further, only at high levels of IBU not regularly found in the bladder was there a significant increase in E. faecalis 1131 attachment at growth inhibitory concentrations of TMP/SMX. There was no effect on the attachment of E. faecalis or E. coli to urothelial cells in the presence of nitrofurantoin. These studies indicate that the beneficial effects of IBU for UTI management are likely mediated through its anti-inflammatory properties rather than direct interactions with uropathogens in the bladder.

Enterococcus faecalis persistence in pediatric patients treated with antibiotic prophylaxis for recurrent urinary tract infections.

AIM: Enterococcus faecalis is one of the most common causes of recurrent urinary tract infection (RUTI), yet enterococcal pathogenesis is poorly understood. Our aims were to identify the prevalence of enterococci in RUTI patients and characterize the enterococcal response to nitrofurantoin and trimethoprim-sulfamethoxazole. MATERIALS & METHODS: We studied pediatric patients receiving antibiotic prophylaxis and those only under clinical observation for 12 months (n = 39). We then assessed the response of uropathogenic E. faecalis to nitrofurantoin and trimethoprim-sulfamethoxazole. RESULTS: Enterococci were isolated from almost half of patients and exposure of Enterococcus to nitrofurantoin increased virulence properties; this did not correlate with increased expression of virulence factors. CONCLUSION: Our results demonstrate that antibiotic prophylaxis may not be suitable for treatment of enterococcal RUTI (NCT02357758).

Dalbavancin in-vitro activity obtained against Gram-positive clinical isolates causing bone and joint infections in US and European hospitals (2011-2016).

BACKGROUND: Osteomyelitis is a difficult-to-treat infection that regularly involves prolonged use of systemic antibiotics. Dalbavancin has demonstrated activity against Gram-positive isolates, and has been considered as a candidate for the treatment of osteomyelitis in adults and children. This study evaluated the activity of dalbavancin against pathogens isolated from bone and joint infections (BJI). METHODS: Eight hundred and one Staphylococcus aureus, 160 coagulase-negative staphylococci (CoNS), 164 ß-haemolytic streptococci (BHS), 82 Enterococcus faecalis and 45 viridans group streptococci (VGS) causing BJI were collected consecutively (2011-2016) and tested for susceptibility by broth microdilution methods. RESULTS: S. aureus (64.0%) was the most common pathogen associated with BJI, followed by BHS (13.1%) and CoNS (12.8%). All S. aureus (33.3% meticillin-resistant) isolates were susceptible to dalbavancin, linezolid and vancomycin, while daptomycin and clindamycin showed susceptibility rates of 99.5% and 89.0%, respectively. The minimum inhibitory concentration (MIC) results for dalbavancin were at least eight-fold lower than these comparators against all S. aureus. Dalbavancin was the most potent agent against CoNS (63.1% meticillin-resistant), followed by daptomycin, linezolid and vancomycin. All E. faecalis isolates were inhibited by dalbavancin at ≤0.25 mg/L (US Food and Drug Administration susceptibility breakpoint), except for three vancomycin-resistant isolates. High susceptibility rates for ampicillin (98.8%), daptomycin (100.0%), linezolid (100.0%) and vancomycin (95.1%) were obtained against E. faecalis. Dalbavancin was very active against BHS (MIC90 ≤0.03 µg/mL), and was the most active agent against VGS (highest MIC ≤0.06 mg/L). Ceftriaxone, daptomycin and vancomycin were also active (93.3-100.0% susceptible) against VGS, whereas clindamycin (84.4% susceptible) had marginal activity. CONCLUSION: Dalbavancin appears to be a viable candidate for treating BJI/osteomyelitis caused by Gram-positive cocci.

Antimicrobial-resistant Faecal Organisms in Algae Products Marketed as Health Supplements.

Dietary supplements are increasingly popular in Irish society. One of these is blue-green algae which is used with a variety health benefits in mind. A batch of Chlorella powder was found to be contaminated with Salmonella species in Ireland in 2015. This prompted additional testing of a total of 8 samples of three different products (Chlorella, Spirulina and Super Greens), for other faecal flora and antimicrobial resistance in any bacteria isolated. All 8 samples cultured enteric flora such as Enterococci, Enterobacteriaceae and Clostridium species. Antimicrobial susceptibility testing revealed one isolate with extended-spectrum ?-lactamase (ESBL) activity and one with carbapenemase activity. Clinicians caring for vulnerable patients should be aware of the potential risk of exposure to antimicrobial resistant bacteria associated with these products.

Ex Vivo Assessment of Photodynamic Therapy in Achieving Microbial Reduction.

The study was to assess the effects of photodynamic therapy (PDT) on root canals contaminated by Enterococcus faecalis (E. faecalis). PDT was performed with 0.005% methylene blue dye and with a low-intensity red emission laser. Microbiological samples were collected before, immediately and 72 hours after instrumentation. Although PDT performed with the chosen light parameters promoted additional microbial reduction, this therapy did not achieve a statistically significant reduction of E. faecalis.

Molecular Identification of Multiple Antibiotic Resistant Fish Pathogenic Enterococcus faecalis and their Control by Medicinal Herbs.

The opportunistic fish pathogen, Enterococcus faecalis has been reported to cause mass mortality in several fish species in different countries. The objectives of this study were to (i) identify E. faecalis from the diseased fishes through molecular techniques; (ii) assess the antibiotic susceptibility profile of E. faecalis isolates; and (iii) control disease in tilapia fish by treatment with medicinal plant extracts. A total of 48 isolates were phenotypically identified as Enterococcus species from tilapia, stinging catfish and walking catfish cultivated in several fish farms in Gazipur. Ten randomly selected isolates were identified as E. faecalis by 16S rRNA gene sequencing. Artificial infection revealed that most of the isolates caused moderate to high mortality in fishes with characteristic disease symptoms. These isolates exhibited resistance to multiple antibiotics in vitro. Bioassay revealed that organic extracts of Tamarindus indica and Emblica officinalis leaves, Allium sativum bulb, and Syzygium aromaticum bud inhibited the growth of E. faecalis. Methanol extracts of A. sativum and methanol and acetone extracts of S. aromaticum significantly reduced the mortality of fish artificially infected with E. faecalis as both preventive and therapeutic agents. This is the first report on molecular identification, and herbal control of fish pathogenic E. faecalis in Bangladesh.

Efficacy and safety of 3 day versus 7 day cefditoren pivoxil regimens for acute uncomplicated cystitis: multicentre, randomized, open-label trial.

BACKGROUND: Fluoroquinolone-non-susceptible Escherichia coli isolated from patients with acute uncomplicated cystitis are a matter of increasing concern. Cefditoren pivoxil is an oral, ß-lactamase-stable, extended-spectrum cephalosporin that is effective against fluoroquinolone-non-susceptible bacteria. OBJECTIVES: To evaluate the clinical and microbiological efficacies of cefditoren pivoxil against acute uncomplicated cystitis and to determine the optimal duration of cefditoren pivoxil treatment. METHODS: We compared 3 and 7 day regimens of cefditoren pivoxil in a multicentre, randomized, open-label study. RESULTS: A total of 104 female patients with acute uncomplicated cystitis were enrolled and randomized into 3 day (n = 51) or 7 day (n = 53) treatment groups. At first visit, 94 bacterial strains were isolated from the 104 participants of which 81.7% (85/104) were E. coli. Clinical and microbiological efficacies were evaluated 5-9 days following administration of the final dose of cefditoren pivoxil. The clinical efficacies of the 3 and 7 day groups were 90.9% (40/44) and 93.2% (41/44), respectively (P = 1.000). The microbiological efficacies of the 3 and 7 day groups were 82.5% (33/40) and 90.2% (37/41), respectively (P = 0.349). There were no adverse events due to cefditoren pivoxil treatment, with the exception of a mild allergic reaction in one patient, after which the cefditoren pivoxil was exchanged for another antimicrobial. CONCLUSIONS: Cefditoren pivoxil is safe and effective for uncomplicated cystitis, with no significant differences in clinical and microbiological efficacies between 3 and 7 day regimens.

Antimicrobial Susceptibility and Characterization of Virulence Genes of Enterococcus faecalis Isolates from Teeth with Failure of the Endodontic Treatment.

INTRODUCTION: The aim of this study was to investigate the prevalence of virulence factors and the antimicrobial resistance of Enterococcus faecalis isolates of teeth with failure of the endodontic treatment. METHODS: Twenty root canal samples were collected from teeth with apical periodontitis. E. faecalis was firstly identified based on phenotypic features and then by 16S ribosomal RNA gene sequencing. The antimicrobial susceptibility was determined by the minimum inhibitory concentration (MIC) of amoxicillin, amoxicillin + clavulanate, azithromycin, benzylpenicillin, ciprofloxacin, clindamycin, chloramphenicol, doxycycline, erythromycin, gentamicin, metronidazole, moxifloxacin, rifampicin, tetracycline, and vancomycin using the E test method. Virulence factors (ace, asa, asa373, cylA, efaA, esp, and gelE) were detected by polymerase chain reaction assay. RESULTS: Amoxicillin + clavulanate was effective against all strains. Intermediate and total resistance was found against the majority of the tested antimicrobials. The susceptibility of some microorganisms to some antimicrobial agents changed according to the evaluation time. MIC50 and MIC90 also varied according to the evaluation time. In relation to the virulence factors of the E faecalis isolates, ace was detected in 100% of the strains, asa (60%), asa373 (15%), efaA (95%), esp (70%), and gelE (75%), whereas cylA was not detected. CONCLUSIONS: It was concluded that E. faecalis isolates from persistent endodontic infections showed varied degrees of intermediate/total resistance to several antimicrobial agents, with amoxicillin + clavulanate being the most effective agent. Moreover, the strains showed different patterns for virulence gene detection.

Optimal dosing regimen of biapenem in Chinese patients with lower respiratory tract infections based on population pharmacokinetic/pharmacodynamic modelling and Monte Carlo simulation.

In this study, a population pharmacokinetic (PPK) model of biapenem in Chinese patients with lower respiratory tract infections (LRTIs) was developed and optimal dosage regimens based on Monte Carlo simulation were proposed. A total of 297 plasma samples from 124 Chinese patients were assayed chromatographically in a prospective, single-centre, open-label study, and pharmacokinetic parameters were analysed using NONMEN. Creatinine clearance (CLCr) was found to be the most significant covariate affecting drug clearance. The final PPK model was: CL (L/h)=9.89+(CLCr-66.56)×0.049; Vc (L)=13; Q (L/h)=8.74; and Vp (L)=4.09. Monte Carlo simulation indicated that for a target of ≥40% T>MIC (duration that the plasma level exceeds the causative pathogen's MIC), the biapenem pharmacokinetic/pharmacodynamic (PK/PD) breakpoint was 4µg/mL for doses of 0.3g every 6h (3-h infusion) and 1.2g (24-h continuous infusion). For a target of ≥80% T>MIC, the PK/PD breakpoint was 4µg/mL for a dose of 1.2g (24-h continuous infusion). The probability of target attainment (PTA) could not achieve ≥90% at the usual biapenem dosage regimen (0.3g every 12h, 0.5-h infusion) when the MIC of the pathogenic bacteria was 4µg/mL, which most likely resulted in unsatisfactory clinical outcomes in Chinese patients with LRTIs. Higher doses and longer infusion time would be appropriate for empirical therapy. When the patient's symptoms indicated a strong suspicion of Pseudomonas aeruginosa or Acinetobacter baumannii infection, it may be more appropriate for combination therapy with other antibacterial agents.

Discordance Between Perioperative Antibiotic Prophylaxis and Wound Infection Cultures in Patients Undergoing Pancreaticoduodenectomy.

IMPORTANCE: Wound infections after pancreaticoduodenectomy (PD) are common. The standard antibiotic prophylaxis given to prevent the infections is often a cephalosporin. However, this decision is rarely guided by microbiology data pertinent to PD, particularly in patients with biliary stents. OBJECTIVE: To analyze the microbiology of post-PD wound infection cultures and the effectiveness of institution-based perioperative antibiotic protocols. DESIGN, SETTING, AND PARTICIPANTS: The pancreatic resection databases of 3 institutions (designated as institutions A, B, or C) were queried on patients undergoing PD from June 1, 2008, to June 1, 2013, and a total of 1623 patients were identified. Perioperative variables as well as microbiology data for intraoperative bile and postoperative wound cultures were analyzed from June 1, 2008, to June 1, 2013. INTERVENTIONS: Perioperative antibiotic administration. MAIN OUTCOMES AND MEASURES: Wound infection microbiology analysis and resistance patterns. RESULTS: Of the 1623 patients who underwent PD, 133 with wound infections (8.2%) were identified. The wound infection rate did not differ significantly across the 3 institutions. The predominant perioperative antibiotics used at institutions A, B, and C were cefoxitin sodium, cefazolin sodium with metronidazole, and ampicillin sodium-sulbactam sodium, respectively. Of the 133 wound infections, 89 (67.1%) were deep-tissue infection, occurring at a median of 8 (range, 1-57) days after PD. A total of 53 (40.0%) of the wound infections required home visiting nurse services on discharge, and 73 (29.1%) of all PD readmissions were attributed to wound infection. Preoperative biliary stenting was the strongest predictor of postoperative wound infection (odds ratio, 2.5; 95% CI, 1.58-3.88; P = .03). There was marked institutional variation in the type of microorganisms cultured from both the intraoperative bile and wound infection cultures (Streptococcus pneumoniae, 114 cultures [47.9%] in institution A vs 3 [4.5%] in institution B; P = .001) and wound infection cultures (predominant microorganism in institution A: Enterococcus faecalis, 18 cultures [51.4%]; institution B: Staphylococcus aureus, 8 [43.9%]; and institution C: Escherichia coli, 17 [36.2%], P = .001). Similarly, antibiotic resistance patterns varied (resistance pattern in institution A: cefoxitin, 29 cultures [53.1%]; institution B: ampicillin-sulbactam, 9 [69.2%]; and institution C: penicillin, 32 [72.7%], P < .001). Microorganisms isolated in intraoperative bile cultures were similar to those identified in wound cultures in patients with post-PD wound infections. CONCLUSIONS AND RELEVANCE: The findings of this large-scale, multi-institutional study indicate that intraoperative bile cultures should be routinely obtained in patients who underwent preoperative endoscopic retrograde cholangiopancreatography since the isolated microorganisms closely correlate with those identified on postoperative wound cultures. Institution-specific internal reviews should amend current protocols for antibiotic prophylaxis to reduce the incidence of wound infections following PD.

Daptomycin versus Vancomycin in an Enterococcus faecalis Endophthalmitis Rabbit Model.

PURPOSE: To compare bactericidal activities of daptomycin (DAP) and vancomycin (VAN) in an experimental rabbit model of Enterococcus faecalis endophthalmitis. MATERIALS AND METHODS: The right vitreous cavities of 24 New Zealand rabbits were inoculated with 100 colony-forming units of E. faecalis; and after 24 h, rabbits were randomly divided into three groups. DAP group (n = 8, 0.2 mg/0.05 ml intravitreally), VAN group (n = 8, 1 mg/0.05 ml intravitreally) and balanced salt solution group (BSS, n = 8, 0.05 ml intravitreally). Clinical examination scores were recorded, and vitreous aspirates were obtained for microbiological analysis on days 0, 1, 2, 3 and 4. Rabbits were sacrificed, and the eyes were enucleated for histopathological assessment. RESULTS: There was no difference between the DAP, VAN and BSS groups in terms of the clinical grading of endophthalmitis 24 h after the inoculation. The bacterial counts were similar between the VAN and DAP groups except on day 1, where it was significantly lower than those in the VAN group (p = 0.003). On day 4, 62% of the eyes treated with DAP, and 50% of the eyes treated with VAN were sterilized. All of the eyes from the BSS group showed increasing bacterial growth from day 0 to day 4. There was no difference between the DAP and VAN groups in terms of the histopathological and clinical examination scores, while they were significantly lower than those in the BSS group. CONCLUSIONS: This study demonstrates evidence of the effectiveness of DAP for the treatment of experimental E. faecalis endophthalmitis.

Effects of ozone and photo-activated disinfection against Enterococcus faecalis biofilms in vitro.

OBJECTIVES: The purpose of this study was to compare the antibacterial effects of gaseous ozone (O3) and photo-activated disinfection (PAD) methods against Enterococcus faecalis (E. faecalis) biofilms. MATERIALS AND METHODS: Sixty-five human mandibular premolars with straight root canals were selected. After root canal preparation, the samples were sterilized and placed into eppendorf tubes with 1 mL brain heart infusion broth containing 1.5×10(8) colony-forming units (CFUs)/mL of E. faecalis. The contaminated samples were then divided into four groups (n=15) according to the disinfection method used: Group 1, Saline (positive control); Group 2, NaOCl (negative control); Group 3, Gaseous O3; and Group 4, PAD. Three non-contaminated teeth were used to control the infection and sterilization process. The CFUs were counted and the data were analyzed statistically. RESULTS: There was a statistically significant difference between the experimental and control groups (P<0.05). The saline group had the highest number of remaining microorganisms. Complete sterilization was achieved in the 2.5% NaOCl group. There were no statistically differences between PAD and gaseous O3 (P>0.05). CONCLUSION: Both PAD and gaseous O3 have a significant antibacterial effect on infected root canals. However, 2.5% NaOCl was superior in terms of its antimicrobial abilities compared with the other disinfection procedures.

The Bacterial Spectrum and Antimicrobial Susceptibility in Female Recurrent Urinary Tract Infection: How Different They Are From Sporadic Single Episodes?

OBJECTIVE: To analyze and compare the etiological uropathogens and the susceptibility profile findings on urine culture between sporadic cases of community-acquired, uncomplicated urinary tract infection (UTI) and recurrent UTI cases in women. MATERIALS AND METHODS: We retrospectively analyzed the clinical data of 1629 women with uncomplicated UTI evaluated at our hospital between January 2007 and December 2012. Patients were divided into 2 groups: (1) no recurrent UTI and (2) recurrent UTI. We analyzed the microbiological findings and compared susceptibility profiles between groups. RESULTS: A total of 420 women were included. Group 1 had 233 (55.5%) patients and group 2 had 187 (44.5%). Escherichia coli was the most common agent in both groups (76.4% and 74.3%, respectively; P = .625), whereas Staphylococcus saprophyticus (8.2%) was the second most common in group 1, and Enterococcus faecalis was the second most common in group 2 (8.0%). Nitrofurantoin was the only oral agent that maintained the susceptibility profile in both groups (87.1% and 88.7%, respectively; P = .883). For E coli infections, only nitrofurantoin and amoxicillin/clavulanate maintained susceptibility rates more than 90% in both groups. CONCLUSION: UTI episodes in patients with recurrent UTI had similar bacterial spectra, but different susceptibility profiles compared with those from patients with nonrecurrent infections. The susceptibility rate for nitrofurantoin in patients with recurrent UTI remained high and comparable to the observed in patients with sporadic UTI, reinforcing its indication for empirical treatment while waiting for urine culture results.

Antimicrobial resistance profile of Enterococcus species isolated from intestinal tracts of hospitalized patients in Jimma, Ethiopia.

BACKGROUND: Multi-drug-resistant Enterococci colonizing the intestinal tract of hospitalized patients are the major source of infection as well as nosocomial spread. Despite worldwide increasing rate of multidrug resistant Enterococci colonization and infection among hospitalized patients, there is scarcity of data from resource limited setting. The present study aimed at determining the antimicrobial resistance profile of Enterococcus species from intestinal tracts of hospitalized patients in Jimma, Ethiopia. METHODS: The study was conducted among hospitalized patients at Jimma University Specialized Hospital, from January to July 2013. Fecal samples were collected and processed for bacterial isolation and susceptibility testing to antimicrobial agents. Stool samples were inoculated onto enterococcus selective media (Bile Esculin azide agar plate) with and without 6 µg/ml of vancomycin. The isolates were identified to genus and species level by cultural characteristics, Gram's stain, catalase test, growth in 6.5% NaCl broth, growth at 45°C, motility test and by using API 20 Streptococcus system. Sensitivity testing was done using Kirby-Bauer disk diffusion method. Minimum inhibitory concentrations for vancomycin were determined using E-test strips. RESULT: Overall, Enterococci were isolated from 114 (76%) of the study subjects. The isolates were Enterococcus faecium (35.1%) followed by Enterococcus faecalis (29.8%), Enterococcus gallinarum (17.5%), Enterococcus casseliflavus (8.8%) and Enterococcus durans (8.8%). Among 114 tested Enterococci isolates, 41 (36%) were resistant to ampicillin, 62 (54.4%) to streptomycin and 39 (34.2%) to gentamycin. Other alternative antibiotics to treat mixed nosocomial infection caused by Enterococci also showed high rate of resistance in vitro: ciprofloxacin (50% of resistance), norfloxacin (49.1%), erythromycin (63.2%), tetracycline (64.9%), chloramphenicol (34.2%), and nitrofrantoin (32.4%). Multiple drug resistance was observed among 89.5% of E. faecium and E. faecalis. Vancomycin resistant Enterococci were observed in 5% of E. faecium isolates. CONCLUSION: This study reveals high rate of fecal colonization by multidrug-resistant Enterococci and prevalence of vancomycin resistance strains. Thus periodic surveillance of antibacterial susceptibilities is recommended to detect emerging resistance and to prevent the spread of antibacterial-resistant strains.

Which is the most effective disinfection method in primary root canals: Conventional or newly developed ones?

BACKGROUND: The aim of the study was to evaluate the antimicrobial activity of the-potassium-titanyl-phosphate--the KTP laser and ozone in of primary root canals. MATERIALS AND METHODS: Sixty primary incisor teeth were selected. The specimens were inoculated with 10 mL Enterococcus faecalis (E. faecalis). Groups: The KTP laser (1,5 W); gaseous ozone (150 s); sodium hypochlorite (NaOCl); saline group. Sterile paper points used to sample bacteria from the canals to tubes containing 5 mL of brain heart infusion broth. Then, 10 mL suspension was incubated in culture media for 24 h. Data were analyzed statistically using Kruskal-Wallis and Mann-Whitney U-test. RESULTS: There were statistically significant differences between all groups (P<0.05). Complete sterilization was achieved in the 2.5% NaOCl group. The number of bacteria were significantly reduced in experimental groups in comparison to the saline group. CONCLUSION: The KTP laser and ozone application provided a significant antibacterial effect in primary root canals; however, 2.5% NaOCl was superior.