Antimicrobial Susceptibility of Clinically Relevant Gram-Positive Anaerobic Cocci Collected over a Three-Year Period in the Netherlands

ABSTRACTThe susceptibility of 14 species of 115 Gram-positive anaerobic cocci (GPAC) was determined for 14 antibiotics. To assure correct identification, strains were genotypically identified by fluorescencein situhybridization and sequencing. Susceptibility differences (MIC50and MIC90) for penicillin G, clindamycin, tigecycline, levofloxacin, amoxicillin-clavulanic acid, cefoxitin, ertapenem, meropenem, metronidazole, and doxycycline were found for the three clinically most relevant GPAC species:Finegoldia magna,Parvimonas micra, andPeptoniphilus harei.

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β-Lactamase Production and Antimicrobial Susceptibility of Oral Heterogeneous Fusobacterium nucleatum Populations in Young Children

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.43.5.1270 ◽

1999 ◽

Vol 43 (5) ◽

pp. 1270-1273 ◽

Cited By ~ 31

Author(s):

E. Könönen ◽

A. Kanervo ◽

K. Salminen ◽

H. Jousimies-Somer

Keyword(s):

Young Children ◽

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Fusobacterium Nucleatum ◽

Penicillin G ◽

Healthy Children ◽

Good Activity ◽

In Vitro Susceptibility ◽

Amoxicillin Clavulanic Acid

ABSTRACT Oral Fusobacterium nucleatum populations from 20 young, healthy children were examined for β-lactamase production. Ten children (50%) harbored, altogether, 25 β-lactamase-positiveF. nucleatum isolates that were identified as F. nucleatum subsp. polymorphum, F. nucleatum subsp. nucleatum, and F. nucleatum subsp. vincentii (J. L. Dzink, M. T. Sheenan, and S. S. Socransky, Int. J. Syst. Bacteriol. 40:74–78, 1990). In vitro susceptibility of these β-lactamase-producing and 26 non-β-lactamase-producing F. nucleatum isolates was tested with penicillin G, amoxicillin-clavulanic acid, tetracycline hydrochloride, metronidazole, trovafloxacin, and azithromycin. Except for penicillin G, the antimicrobials exhibited good activity against all F. nucleatum isolates.

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Breast Abscesses Caused by Anaerobic Microorganisms: Clinical and Microbiological Characteristics

Antibiotics ◽

10.3390/antibiotics9060341 ◽

2020 ◽

Vol 9 (6) ◽

pp. 341 ◽

Cited By ~ 1

Author(s):

Fernando Cobo ◽

Vicente Guillot ◽

José María Navarro-Marí

Keyword(s):

Clavulanic Acid ◽

High Resistance ◽

Antimicrobial Susceptibility ◽

Susceptibility Testing ◽

Antimicrobial Susceptibility Testing ◽

Local Data ◽

Gram Positive ◽

Gram Negative ◽

Amoxicillin Clavulanic Acid ◽

Resistance Rates

The objectives of this study were to report the antimicrobial susceptibility of 35 clinically significant anaerobic bacteria isolated from breast abscesses between March 2017 and February 2020 in a tertiary hospital in Granada (Spain) and to describe key clinical features of the patients. Species identification was performed mainly by MALDI-TOF MS. Antimicrobial susceptibility tests were carried out against benzylpenicillin, amoxicillin–clavulanic acid, imipenem, moxifloxacin, clindamycin, metronidazole, and piperacillin–tazobactam using the gradient diffusion technique and European Committee on Antimicrobial Susceptibility Testing EUCAST breakpoints (except for moxifloxacin). The most frequent anaerobes were Finegoldia magna (31.4%; n = 11), Actinomyces spp. (17.1%; n = 6), Propionibacterium spp. (17.1%; n = 6), and Prevotella spp. (14.2%; n = 5). Imipenem, amoxicillin–clavulanic acid, and piperacillin–tazobactam were universally active against all genera tested. High overall resistance rates to clindamycin were observed, especially for Gram-positive anaerobic cocci (56.2%) and Gram-positive anaerobic bacilli (38.4%). High resistance rates to metronidazole were also observed for Gram-positive (76.9%) and Gram-negative anaerobic bacilli (50%). High resistance rates to moxifloxacin were found for Gram-negative anaerobic bacilli (50%) and Gram-positive anaerobic cocci (31.2%). No breast abscess cases of Bacteroides spp. were detected. Routine antimicrobial susceptibility testing for anaerobes in breast abscesses may contribute to allow empirical therapies to be selected in accordance with local data on resistant strains.

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Clinical Findings and Antimicrobial Susceptibility of Anaerobic Bacteria Isolated in Bloodstream Infections

Antibiotics ◽

10.3390/antibiotics9060345 ◽

2020 ◽

Vol 9 (6) ◽

pp. 345 ◽

Cited By ~ 1

Author(s):

Fernando Cobo ◽

Jaime Borrego ◽

Esther Gómez ◽

Isabel Casanovas ◽

Elizabeth Calatrava ◽

...

Keyword(s):

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Tertiary Care ◽

Anaerobic Bacteria ◽

Bloodstream Infections ◽

Care Hospital ◽

Gram Positive ◽

Amoxicillin Clavulanic Acid ◽

Almost All ◽

Resistance Rates

The objectives of this study were to report on the antimicrobial susceptibility of 141 clinically significant anaerobic bacteria isolated from bloodstream infections between January 2016 and April 2020 in a tertiary-care hospital in Granada (Spain) and to describe the main clinical features of the patients. Species identification was performed by MALDI-TOF MS (Bruker Daltonics, Billerica, MA, USA). Antimicrobial susceptibility tests were performed against penicillin, amoxicillin-clavulanic acid, imipenem, moxifloxacin, clindamycin, metronidazole, and piperacillin-tazobactam using the gradient diffusion technique and EUCAST breakpoints, except for moxifloxacin (CLSI breakpoints). The most frequent anaerobes were Bacteroides (43.9%, n = 62), Clostridium (24.1%, n = 34) and Gram-positive anaerobic cocci (GPACs) (15.6%, n = 22). Almost all tested anaerobes were susceptible to imipenem and amoxicillin-clavulanic acid, except for Bacteroides. High overall resistance rates to clindamycin were observed, especially for Gram-positive anaerobic cocci (GPACs) (54.5%) and for Bacteroides spp. (45.1%). Overall, low resistance rates to almost all antibiotics were observed for Clostridium. High resistance rates to penicillin were also observed for Gram-positive anaerobic bacilli (GPABs) (44.4%), as well as to metronidazole (22.2%), although only nine isolates were included. Antimicrobial susceptibility testing for anaerobes should always be performed in severe infections, such as those localized in the bloodstream. The information obtained contributes to selecting empirical treatments according with local data on resistance.

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Finding of coagulase negative staphylococci in the herd with an increased number of somatic cells in milk and their antimicrobial susceptibility

Veterinarski glasnik ◽

10.2298/vetgl1304175k ◽

2013 ◽

Vol 67 (3-4) ◽

pp. 175-185

Author(s):

Vera Katic ◽

Natasa Rajic-Savic

Keyword(s):

Clavulanic Acid ◽

Somatic Cells ◽

Inhibition Zone ◽

Subclinical Mastitis ◽

Blood Agar ◽

Penicillin G ◽

Coagulase Negative Staphylococci ◽

Milk Samples ◽

Causative Agents ◽

Amoxicillin Clavulanic Acid

Coagulase-negative staphylococci (CNS) are generally considered to be opportunistic pathogens. Controlling CNS mastitis is difficult because the epidemiology is not clear, and the CNS group consists of about 40 different Staphylococcus species. Therefore, the aim of this study was to determine the prevalence of coagulasenegative staphylococci in milk of the cows with subclinical mastitis, as well as to determine different CNS species isolated from quarter milk samples for their susceptibility to antimicrobials used commonly for mastitis therapy. On the farm where there was found an increase of somatic cells in bulk milk, 112 dairy cows were examined by mastitis test. From 52 udder quarters where mastitis test showed an increase of somatic cells, milk samples were taken for bacteriological examination. For isolating the causes of mastitis there was used blood agar. Identification of the causative agents of mastitis was carried out on the basis of colony appearance on blood agar and their physiological characteristics. Coagulasepositive staphylococci sensitivity which cause mastitis was tested by Kirby Bauer method. For susceptibility testing there were used commercially produced discs containing: 10 IU penicillin, amoxicillin/clavulanic acid (20 +10 ?g), cloxacillin 25 ?g, 30 ?g amoxicillin, cephalexin 30 ?g, ceftiofur 30 ?g, 15 ?g lincomycin, gentamicin and tetracycline 30 ?g. The sensitivity of microorganisms was evaluated on the basis of inhibition zone diameter recommended by the manufacturer and was labeled as sensitive (S) moderately sensitive (I) or resistant (R). Coagulase-negative staphylococci were isolated from 61.53% of samples from cows with subclinical mastitis, making them the most common cause of subclinical mastitis. The highest resistance of coagulase-negative staphylococci was found to penicillin G (58.33% of isolates). Full sensitivity of coagulase-negative staphylococci was found to amoxicillin / clavulanic acid (100% of isolates), a good sensitivity to ceftiofur (83.33% of isolates), cefalexin (70.83% of isolates) and ceftriaxone (41.66% of isolates).

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Antimicrobial susceptibility and molecular characterization of Salmonella serovar Ndolo isolated from outbreaks in cattle and horses

Ciência Rural ◽

10.1590/0103-8478cr20180688 ◽

2018 ◽

Vol 48 (12) ◽

Cited By ~ 2

Author(s):

Carolina Pantuzza Ramos ◽

Rafael Gariglio Clark Xavier ◽

Carlos Augusto Gomes Leal ◽

Elias Jorge Facury Filho ◽

Antonio Ultimo de Carvalho ◽

...

Keyword(s):

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Virulence Genes ◽

Susceptibility Testing ◽

Domestic Animals ◽

Amoxicillin Clavulanic Acid ◽

Resistant Strains ◽

Human Infections ◽

First Time

ABSTRACT: The present study aimed to describe and characterize, for the first time, two outbreaks of salmonellosis caused by Salmonella Ndolo in foals and calves in Brazil and compare the isolated strains with S. Ndolo previously identified in asymptomatic reptiles. The affected calves and foals presented fever, lethargy, and profuse diarrhea. Isolated strains were subjected to antimicrobial susceptibility testing, characterized according to virulence genes, and fingerprinted by ERIC-PCR. Salmonella Ndolo was identified in fecal samples from two foals and four calves. One isolate from a calf was resistant to amoxicillin/clavulanic acid, trimethoprim/sulfamethoxazole, and florfenicol. Strains from two other calves were resistant to oxytetracycline. All virulence genes tested were present in the isolates, and two major clusters of closely related strains were identified by ERIC-PCR, each per outbreak. This is the first report of Salmonella Ndolo infection in domestic and symptomatic animals. Previously, this serovar had been identified only in human infections. The presence of relevant virulence genes in all Salmonella Ndolo isolates and the detection of antimicrobial multi-resistant strains highlighted the importance of monitoring serovars associated with salmonellosis in domestic animals.

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Antimicrobial Susceptibility of Subgingival Bacterial Flora in Cats with Gingivitis

Journal of Veterinary Dentistry ◽

10.1177/089875649501200406 ◽

1995 ◽

Vol 12 (4) ◽

pp. 157-160 ◽

Cited By ~ 14

Author(s):

C.E. Harvey ◽

C. Thornsberry ◽

B.R. Miller ◽

F. S. Shofer

Keyword(s):

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

Antimicrobial Agents ◽

Bacterial Flora ◽

In Vitro Susceptibility ◽

Amoxicillin Clavulanic Acid ◽

Aerobic And Anaerobic

The aerobic and anaerobic flora from gingival pockets of 40 cats with established gingivitis were cultured. The susceptibility of each isolate to four antimicrobial agents currently approved for use in cats (amoxicillin-clavulanic acid; clindamycin; cefadroxil; enrofloxacin) was determined. Amoxicillin-clavulanic acid (Clavamox®) had the highest in-vitro susceptibility against all isolates (92%) and all anaerobes (99% [co-equal with clindamycin]) tested; enrofloxacin (Baytril®) had the highest in-vitro susceptibility against all aerobes (90%) tested.

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Multidrug-resistant pathogens isolated from ready-to-eat salads available at a local market in Pakistan

British Food Journal ◽

10.1108/bfj-02-2016-0058 ◽

2016 ◽

Vol 118 (8) ◽

pp. 2068-2075 ◽

Cited By ~ 6

Author(s):

Sana Ilyas ◽

Muhammad Usman Qamar ◽

Muhammad Hidayat Rasool ◽

Nazia Abdulhaq ◽

Zeeshan Nawaz

Keyword(s):

Staphylococcus Aureus ◽

Clavulanic Acid ◽

Antimicrobial Susceptibility ◽

National Level ◽

Multidrug Resistant ◽

Effective Control ◽

Local Market ◽

Content Type ◽

Amoxicillin Clavulanic Acid ◽

Multidrug Resistant Pathogens

Purpose – The purpose of this paper is to evaluate the frequency and antimicrobial susceptibility pattern of pathogens present in ready-to-eat salads available at a local market. Design/methodology/approach – A 100 salad samples were collected aseptically. Each sample (25 g) was homogenized in 225 ml of sterile peptone water and was serially diluted up to 1×106. Dilutions were inoculated on nutrient agar by surface spread plate technique. Aerobic colony count (ACC) was estimated by counting the colonies. Bacterial isolates were cultured on blood and MacConkey agar and identified on the basis of their morphology, culture characteristics and confirmed by API 20E and 20NE. Antimicrobial susceptibility was determined as per CLSI 2014. Findings – ACC range was 1.1×103 cfu/g to 5.8×109 cfu/g. Among these the highest ACC was found in channa chat (4.9×104 to 5.8×109 cfu/g). A total of 127 microorganisms were identified; 73 were gram negative rods (GNRs) and 24 were gram positive cocci (GPC). Among GNRs; Klebsiella spp. (n=18) was the predominant whereas among GPC, Staphylococcus aureus (n=6) were the chief pathogen. Klebsiella spp. showed 100 percent resistance to ampicillin, 89-78 percent to amoxicillin/clavulanic acid and 33 percent to imipenem, however, Enterobacter spp. were resistant to ampicillin (100 percent) amoxicillin/clavulanic acid (77 percent) and imipenem (23 percent). Staphylococcus aureus showed resistance to co-amoxiclav (83 percent) and penicillin (75 percent). Practical implications – This study revealed that effective control measures must been implemented and respected by throughout the entire food chain and better surveillance studies should be performed at national level to reduce the spread of bacteria by fresh salads. Originality/value – This paper explore the high prevalence of multidrug-resistant pathogens in different salads and most of the salads were found to be unhygienic for consumption.

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Culture and molecular analysis of Enterococcus faecalis and antimicrobial susceptibility of clinical isolates from patients with failure endodontic treatment

Brazilian Dental Science ◽

10.14295/bds.2014.v17i3.1016 ◽

2014 ◽

Vol 17 (3) ◽

pp. 83 ◽

Cited By ~ 3

Author(s):

Marcos Sergio Endo ◽

Fernanda Graziela Corrêa Signoretti ◽

Vivian Sayuri Kitayama ◽

Ariane Cássia Salustiano Marinho ◽

Frederico Canato Martinho ◽

...

Keyword(s):

Clavulanic Acid ◽

Enterococcus Faecalis ◽

Antimicrobial Susceptibility ◽

Test System ◽

Culture Technique ◽

Pcr Assay ◽

Culture Methods ◽

Minimal Inhibitory Concentrations ◽

Amoxicillin Clavulanic Acid

Objective: The aim of this study was to evaluate the minimal inhibitory concentrations (MIC) of different antibiotic agents against to the most prevalent microorganism found in root-filled canals by culture and molecular approaches. Material and Methods: The microbial samples were taken either from thirty root-filled canals after removal of gutta-percha. Culture methods and 16s rDNA assay were used to identify the E faecails present in the samples. The antimicrobial susceptibilities of the isolates of E faecalis were determined by MIC values using the E test System and interpreted according to the Clinical and Laboratory Standards Institute guidelines. The following antibiotics were used: benzylpenicillin, amoxicillin, amoxicillin-clavulanic acid, erythromycin, azithromycin, vancomycin, chloramphenicol, tetracycline, doxycycline, ciprofloxacin, rifampicin and moxifloxacin. Results: E faecalis were isolated (7/30) and detected (13/30) by culture and PCR assay, respectively. All tested E faecalis (n=12) were highly sensitive to amoxicillin, moxifloxacin, vancomycin, benzylpenicillin and amoxicillin-clavulanic acid. Some antibiotics were resistant against E faecalis strains such as rifampicin (4/12), tetracycline (2/12), doxycycline (1/12), erythromycin (3/12) and azythromycin (8/12). Conclusion: Amoxicillin, amoxicillin-clavulanic acid, benzylpenicillin, vancomycin and moxifloxacin were the most active antibiotics, in vitro, against E faecalis clinical strains, with all the isolates being susceptible. Azithromycin and erythromycin were least effective, with none percentage of isolates being susceptible, during laboratory testing. Moreover, E faecalis were identified more frequently by PCR assay than by culture technique.Keywords: Retreatment; Antibiotics, antimicrobial susceptibility; Enterococcus faecalis; Antibiotic resistance.

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Nano Drug Deliverer for Ampicillin, Clavulanic Acid, Imipenem, Penicillin G and Ticarcillin

Journal of Computational and Theoretical Nanoscience ◽

10.1166/jctn.2016.5964 ◽

2016 ◽

Vol 13 (10) ◽

pp. 7144-7155

Author(s):

Maryam Derakhshandeh ◽

Majid Monajjemi

Keyword(s):

Drug Delivery ◽

Clavulanic Acid ◽

Large Scale ◽

Penicillin G ◽

Effect Of Temperature ◽

Phenoxyacetic Acid ◽

Scale Production ◽

Electronic Effects ◽

Beta Lactam ◽

Gram Positive

Ampicillin, Clavulanic acid, Imipenem, Penicillin G and Ticarcillin properties for the drug delivery with binding to SWCNNTs and SWBNNTs have been studied. Penicillin and its alteration Penicillin G or phenoxyacetic acid for Penicillin V is used for large scale production. Penicillin and other cell wall inhibitors are primarily specific against Gram positive bacteria because of higher percentage of peptidoglycan in the cell walls of these organisms. Ampicillin belonging to the penicillin group of beta lactam antibiotics, ampicillin is able to penetrate Gram positive and some Gram-negative bacteria. Imipenem (Primaxin) is an intravenous β-lactam antibiotic discovered by Merck scientists Burton Christensen, William Leanza, and Kenneth Wildonger in 1980. It was the first member of the carbapenem class of antibiotics. Based on our previous works we have modeled and simulated a drug delivery system of those antibiotics. The investigation of those antibiotics in binding with single-walled carbon nanotube (SWCNT) and SWBNNTs have been studied by theoretical methods. It has been established the best structural and functional of those antibiotics. A number of computational chemistry studies carried out to understand the conformational preferences that may be attributed to stereo electronic effects. These results show the minimized structure of mentioned antibiotics with SWCNTs and SWBNNTs, calculated potential energy for important dihedral angles, and the effect of temperature on geometry of optimized structure. NMR by GIAO approximation, have been applied for determination of the situation in antibiotics-SWCNT and shifting. This model provides an atomistic analysis of the antibiotics-SWCNT strategy and its implications for further investigations of drugs.

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