Efficacy of Vancomycin with Fosfomycin against Vancomycin-Resistant Enterococcus Strains Using Agar Dilution Method

2021 ◽  
Vol 67 (01/2021) ◽  
Author(s):  
Gulseren Aktas
Keyword(s):  
Dilution Method ◽  
Agar Dilution Method ◽  
Vancomycin Resistant Enterococcus ◽  
Agar Dilution ◽  
Vancomycin Resistant

scholarly journals High Frequency of Vancomycin-Resistant Enterococci in Sewage and Fecal Samples of Healthy Carriers

2019 ◽  
Vol 13 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Fakhri Haghi ◽  
Neda Shirmohammadlou ◽  
Rabab Bagheri ◽  
Sama Jamali ◽  
Habib Zeighami
Keyword(s):  
Antibiotic Resistance ◽  
High Frequency ◽  
Municipal Sewage ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Fecal Samples ◽  
Vancomycin Resistant Enterococci ◽  
Agar Dilution ◽  
Vancomycin Resistant ◽  
Healthy Carriers

Objectives:Enterococci are part of the microbial flora of the gastrointestinal tract of animals and human and can be released into the environment through fecal materials. These microorganisms play an important role in the dissemination of antibiotic resistance genes. Vancomycin-Resistant Enterococci (VRE) have been obtained in municipal sewage, hospital and agricultural wastes and healthy carriers. The aim of this study was to investigate the frequency of VRE in sewage and fecal samples of healthy carriers.Methods:This study was performed on fecal specimens of 100 healthy carriers and 100 samples of sewage in Zanjan Province. Fecal and sewage samples were cultured on Trypticase Soy Agar and biochemical tests were performed for Enterococci identification. Antimicrobial susceptibility testing was performed as CLSI guidelines and vancomycin resistance was determined using the agar dilution method.Result:Of 200 cultured samples, 141 isolates of Enterococci were detected. 64 isolates were detected from fecal and 77 were isolated from the sewage samples. Antibiotic resistance profile of fecal isolates was as follows: tetracycline (57.8%), ciprofloxacin (54.7%), phosphomycin (54.7%), erythromycin (51.5%), chloramphenicol (12.5%), amoxicillin (21.8%) and gatifloxacin (23.5%). Also for the sewage samples, the most antibiotic resistance was detected against ciprofloxacin (76.6%) followed by tetracycline (74%), erythromycin (68.8%), phosphomycin (61%). According to Agar dilution method, among 141 isolates of Enterococci, 15 (10.6%) isolates were vancomycin resistant: 11 of sewage isolates (14.3%) and 4 of the carrier isolates (6.2%).Conclusion:Our study describes the high frequency of VRE in municipal sewage and healthy carriers. Regarding the importance of VRE strains in the clinical and environment, it seems necessary to follow up on the issue.

scholarly journals In Vitro Antimicrobial Activity of Tigecycline

2015 ◽  
Vol 13 (2) ◽  
pp. 35-38
Author(s):  
Sabita Bhatta ◽  
Babli Basu ◽  
Chandrasekhar Narharrao Chaudhary ◽  
Ashok Kumar Praharaj
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Susceptibility ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Diffusion Method ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Klebsiella Pneumonia ◽  
Methicillin Resistant ◽  
Agar Dilution ◽  
Vancomycin Resistant

Introduction: Tigecycline is a novel glycylcycline  derivative of the tetracycline with activity against a wide range of  organisms including Methicillin resistant Staphylococcus aureus, Vancomycin  resistant  Enterococcus , Extended spectrum beta lactamase   producing  (Escherichia coli , Klebsiella  pneumonia)  and Acinetobacter species.  The aim of the study was to assess effectiveness of the drug against methicillin resistant Staphylococcus aureus (MRSA), vancomycin resistant enterococci (VRE), ESBL producers and carbapenem resistant Acinetobacter baumannii and to compare the efficacy of different methods of antimicrobial susceptibility testing for Tigecycline.Methods: A total of 250 clinical isolates were processed and identified by conventional methods. In all the 250 isolates, antimicrobial susceptibility was carried out by disc diffusion method , Minimum inhibitory test by agar dilution method (MIC) and in 30 isolates of A baumannii  MIC was also done by E test.Results: Out of 250 isolates, 236 isolates were sensitive to tigecycline by agar dilution method while only 159 were sensitive by disk diffusion method.Conclusion: Marked discordance was observed between the results of two different methods (DDT & Agar dilution method) for E coli, Klebsiella spp and A baumannii, where significant number of isolates were resistant to tigecycline by DDT as compared to AD method. But results of MIC by agar dilution method & E test were in concordance for A. baumannii.

Antimicrobial susceptibility testing of vancomycin-resistant Enterococcus by the VITEK 2 system, and comparison with two NCCLS reference methods

2004 ◽  
Vol 53 (12) ◽  
pp. 1229-1232 ◽  
Author(s):  
Intetsu Kobayashi ◽  
Hiroe Muraoka ◽  
Takako Iyoda ◽  
Minoru Nishida ◽  
Miyuki Hasegawa ◽  
...  
Keyword(s):  
Antimicrobial Susceptibility ◽  
Susceptibility Testing ◽  
Antimicrobial Susceptibility Testing ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Major Error ◽  
Reference Methods ◽  
Agar Dilution ◽  
Vitek 2 ◽  
Vancomycin Resistant

We evaluated the automated VITEK 2 system (bioMérieux) for antimicrobial susceptibility testing of vancomycin-resistant Enterococcus (VRE). The results obtained with the VITEK 2 system were compared to those obtained using two NCCLS reference methods. The VITEK 2 system produced MICs for penicillin G, erythromycin and vancomycin that were very similar to those of the reference agar-dilution test with all results being within a twofold dilution. When MICs of teicoplanin for these isolates were measured by the agar-dilution method and VITEK 2 system, there was one ‘very major’ error and seven ‘minor’ errors. There were no ‘major’ errors for any of the antibiotics tested. When the results obtained by the micro broth-dilution method were compared with those obtained by the VITEK 2 system, there was one ‘very major’ error for teicoplanin by the VITEK 2 system, as was the case with the agar-dilution method. There were two ‘minor’ errors for erythromycin and seven ‘minor’ errors for teicoplanin. There were no ‘major’ errors for any of the antibiotics tested. The 35 VRE strains identified phenotypically by the VITEK 2 Advanced Expert System included nine of Enterococcus faecalis and 23 of Enterococcus faecium. Neither Enterococcus avium nor Enterococcus hirae were identified. A total of 32 phenotypes were classified into 22 VanA and 10 VanB strains. PCR genotyping demonstrated 23 vanA + and nine vanB + strains. There were differences between the VITEK 2 system results and those of PCR. Overall, 54.3 % of the test results were obtained within 7 h. All MIC values for the 35 VRE isolates were determined within 13 h of completing incubation. The VITEK 2 system is a simple method for accurately detecting vancomycin-resistant strains of Enterococcus and can be used to rapidly determine MICs.

scholarly journals Evaluation of the Antimicrobial Activity of Some Components of the Essential Oils of Plants Used in the Traditional Medicine of the Tehuacán-Cuicatlán Valley, Puebla, México

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 295
Author(s):  
Sebastián Candelaria-Dueñas ◽  
Rocío Serrano-Parrales ◽  
Marisol Ávila-Romero ◽  
Samuel Meraz-Martínez ◽  
Julieta Orozco-Martínez ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Essential Oils ◽  
Qualitative Evaluation ◽  
Bactericidal Effect ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Diffusion Technique ◽  
Agar Dilution

In Tehuacán-Cuicatlán valley (Mexico), studies have been carried out on the essential oils of medicinal plants with antimicrobial activity and it was found that they present compounds in common such as: α-pinene, β-pinene, carvacrol, eugenol, limonene, myrcene, ocimene, cineole, methyl salicylate, farnesene, and thymol. The goal of this study was to assess the antimicrobial activity of essential oils’ compounds. The qualitative evaluation was carried out by the Kirby Baüer agar diffusion technique in Gram-positive bacteria (11 strains), Gram-negative bacteria (18 strains), and yeasts (8 strains). For the determination of the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), the agar dilution method was used. All the evaluated compounds presented antimicrobial activity. The compounds eugenol and carvacrol showed the largest inhibition zones. Regarding yeasts, the compounds ocimene, cineole, and farnesene did not show any activity. The compounds eugenol, carvacrol, and thymol presented the lowest MIC; bactericidal effect was observed at MIC level for S. aureus 75MR, E. coli 128 MR, and C albicans CUSI, for different compounds, eugenol, carvacrol, and thymol. Finally, this study shows that the essential oils of plants used by the population of Tehuacán-Cuicatlán valley share compounds and some of them have antibacterial and fungicidal activity.

scholarly journals Antibiotic sensitivities of Neisseria meningitidis isolates from patients and carriers in Greece

1992 ◽  
Vol 108 (3) ◽  
pp. 449-455 ◽  
Author(s):  
G. Tzanakaki ◽  
C. C. Blackwell ◽  
J. Kremastinou ◽  
C. Kallergi ◽  
G. Kouppari ◽  
...  
Keyword(s):  
Neisseria Meningitidis ◽  
School Children ◽  
Penicillin G ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Southern Europe ◽  
Agar Dilution ◽  
Of Greece

SUMMARYUsage of antibiotics in southern Europe is less well regulated than in northern countries. The proportion (48%) of meningococci in Spain insensitive to penicillin (MIC ≥ 0·1 mg/l) prompted this investigation of antibiotic sensitivities of isolates from Greek patients with meningitis (31) and carriers (47 school-children and 472 recruits). The agar dilution method was used to determine MIC to penicillin G (PN), sulphamethoxazole (SU), rifampicin (RF), cefaclor (CF) and ciprofloxacin (CP).The proportion of isolates insensitive to PN was 48% for isolates from patients, 19% from school-children and 36·6% from recruits. Resistance to SU (MIC ≥ 16 mg/l) was found in 16% of those from patients, 10·6% from children and 40% from recruits. None of the isolates from patients was resistant to RF (≥ 1 mg/l) but 6% of those from carriers were. Resistance to CF (≥ 4 mg/l) was found in 9·2% of patient isolates, 6·4% from children and 23·7% from recruits. All isolates except one were sensitive to CP (MIC range < 0·0015–0·125 mg/l).Resistances to PN, SU and RF were analysed by serogroup, serotype and subtype of the bacteria. The proportion of resistant isolates showed some variation between different areas of Greece, but it was not statistically significant.

scholarly journals Prevalence and characterization of extended spectrum beta-lactamase-producing Enterobacter cloacae strains in Algeria

2013 ◽  
Vol 7 (11) ◽  
pp. 804-811 ◽  
Author(s):  
Sabrina Nedjai ◽  
Abouddihaj Barguigua ◽  
Nassima Djahmi ◽  
Loubna Jamali ◽  
Khalid Zerouali ◽  
...  
Keyword(s):  
Enterobacter Cloacae ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Extended Spectrum Beta Lactamase ◽  
Agar Dilution ◽  
Synergy Test ◽  
High Level ◽  
Genomic Typing ◽  
Microbiological Data

Introduction: Expended spectrum β-lactamase (ESBL)-producing Enterobacter cloacae is an important nosocomial pathogen. In this study, the prevalence and the molecular epidemiology of ESBL producing E. cloacae strains isolated from various hospitals in Annaba, Algeria were investigated. Methodology: The study involved 63 isolates of E. cloacae obtained during 2009 at the four hospitals in Annaba. The detection of ESBL was performed using the double-disk synergy test and the combined disk test. Minimum inhibitory concentrations (MICs) were determined using the agar dilution method. The presence of blaCTX-M, blaSHV, blaTEM, and blaDHA β-lactamase genes was evaluated by PCR, and genomic typing was determined by pulsed-field gel electrophoresis (PFGE) analysis. The clinical and microbiological data were entered into the EpiI Info database. Results: Thirty isolates (47.6%) had an ESBL phenotype. BlaCTX-M group1 (76%); blaTEM (70%) were the most prevalent, followed by blaDHA (16.6%) and blaSHV (10%). Eighteen strains expressed at least two bla genes. MICs revealed a high level of resistance to cefotaxime, ceftazidime, and cefepime.  PFGE revealed an epidemic clonal dissemination of these isolates. Various risk factors associated with the occurrence of ESBL-producing E. cloacae were detected. Conclusions: A higher frequency of ESBL-producing isolates and a diversity of β-lactamases were detected among ESBL-producing E. cloacae; these resulted from an epidemic clonal dissemination and high transference of ESBL genes between bacteria in hospital settings. Strict measures will be required to control the further spread of these pathogens in hospital settings.

scholarly journals Antifungal and Antibacterial Metabolites from a French Poplar Type Propolis

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Séverine Boisard ◽  
Anne-Marie Le Ray ◽  
Anne Landreau ◽  
Marie Kempf ◽  
Viviane Cassisa ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Antifungal Activity ◽  
Antimicrobial Effect ◽  
Antibacterial Activities ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Gram Positive ◽  
Weak Activity ◽  
Agar Dilution

During this study, thein vitroantifungal and antibacterial activities of different extracts (aqueous and organic) obtained from a French propolis batch were evaluated. Antifungal activity was evaluated by broth microdilution on three pathogenic strains:Candida albicans, C. glabrata, andAspergillus fumigatus. Antibacterial activity was assayed using agar dilution method on 36 Gram-negative and Gram-positive strains includingStaphylococcus aureus. Organic extracts showed a significant antifungal activity againstC. albicansandC. glabrata(MIC80between 16 and 31 µg/mL) but only a weak activity towardsA. fumigatus(MIC80= 250 µg/mL). DCM based extracts exhibited a selective Gram-positive antibacterial activity, especially againstS. aureus(SA) and several of its methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains (MIC10030–97 µg/mL). A new and active derivative of catechin was also identified whereas a synergistic antimicrobial effect was noticed during this study.

scholarly journals Antimicrobial activity of honeys from two stingless honeybee species and Apis mellifera (Hymenoptera: Apidae) against pathogenic microorganisms

2014 ◽  
Vol 44 (2) ◽  
pp. 287-290 ◽  
Author(s):  
Carolinie Batista Nobre da Cruz ◽  
Fabio Alessandro Pieri ◽  
Gislene Almeida Carvalho-Zilse ◽  
Patrícia Puccinelli Orlandi ◽  
Carlos Gustavo Nunes-Silva ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Apis Mellifera ◽  
Antimicrobial Agents ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Therapeutic Approaches ◽  
E Coli ◽  
Agar Dilution ◽  
Amazonas State

Honeys are described possessing different properties including antimicrobial. Many studies have presented this activity of honeys produced by Apis mellifera bees, however studies including activities of stingless bees honeys are scarce. The aim of this study was to compare the antimicrobial activity of honeys collected in the Amazonas State from Melipona compressipes, Melipona seminigra and Apis mellifera against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Chromobacterium violaceum, and Candida albicans. Minimum inhibitory concentrations were determined using the agar dilution method with Müller-Hinton agar (for bacteria) or Saboraud agar (for yeast). Staphylococcus aureus and E. faecalis were inhibited by all honeys at concentrations below 12%, while E. coli and C. violaceum were inhibited by stingless bee honeys at concentrations between 10 and 20%. A. mellifera honey inhibited E. coli at a concentration of 7% and Candida violaceum at 0.7%. C. albicans were inhibited only with honey concentrations between 30 and 40%. All examined honey had antimicrobial activity against the tested pathogens, thus serving as potential antimicrobial agents for several therapeutic approaches.

scholarly journals Drug resistance of yeasts isolated from oropharyngeal candidiasis in aids patients

1998 ◽  
Vol 29 (4) ◽  
pp. 271-275
Author(s):  
Maria do Rosário Rodrigues Silva ◽  
Claudete Rodrigues de Paula ◽  
Soraya Cristina Silva ◽  
Théo Rodrigues Costa ◽  
Márcio Rodrigues Costa
Keyword(s):  
Amphotericin B ◽  
High Frequency ◽  
Inhibitory Concentration ◽  
Serum Levels ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Oropharyngeal Candidiasis ◽  
Candida Spp ◽  
Aids Patients ◽  
Agar Dilution

Candida spp was isolated from 59 (68.60%) out of eighty six samples of oral mucosa of AIDS patients. The identification, based or the production of a germ tube and chlamydospores, and on the assimilation and fermentation of carbohydrates, revealed 52 strains (88.13%) of C. albicans, 4 (6.77%) of C. tropicalis and 3 (5.08%) of C. krusei. The susceptibility of these strains to amphotericin B, flucytosine, itraconazole, fluconazole and ketoconazole was determined using the agar dilution method. Comparing the minimum inhibitory concentration values found in the susceptibility test with the serum levels achieved by these drugs, only 8.47% and 5.08% of the yeasts strains proved to be resistant to amphotericin B and flucitosyne, respectively. A high frequency of strains resistant to azole derivatives (25.42%, to itraconazole, 45.76%, to ketoconazole and 66.10% to fluconazole) was observed.

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