Treatment of a cochlear implant biofilm infection: a potential role for alternative antimicrobial agents

2010 ◽  
Vol 124 (7) ◽  
pp. 729-738 ◽  
Author(s):  
A J Brady ◽  
T B Farnan ◽  
J G Toner ◽  
D F Gilpin ◽  
M M Tunney
Keyword(s):  
Cochlear Implant ◽  
Cochlear Implants ◽  
Antimicrobial Agents ◽  
Antimicrobial Treatment ◽  
Novel Agents ◽  
Tea Tree Oil ◽  
Tea Tree ◽  
Microdilution Method ◽  
Broth Microdilution Method

AbstractObjective:This study aimed to investigate antimicrobial treatment of an infected cochlear implant, undertaken in an attempt to salvage the infected device.Methods:We used the broth microdilution method to assess the susceptibility of meticillin-sensitive Staphylococcus aureus isolate, cultured from an infected cochlear implant, to common antimicrobial agents as well as to novel agents such as tea tree oil. To better simulate in vivo conditions, where bacteria grow as microcolonies encased in glycocalyx, the bactericidal activity of selected antimicrobial agents against the isolate growing in biofilm were also compared.Results:When grown planktonically, the S aureus isolate was susceptible to 17 of the 18 antimicrobials tested. However, when grown in biofilm, it was resistant to all conventional antimicrobials. In contrast, 5 per cent tea tree oil completely eradicated the biofilm following exposure for 1 hour.Conclusion:Treatment of infected cochlear implants with novel agents such as tea tree oil could significantly improve salvage outcome.

scholarly journals Antimicrobial Susceptibility of Bacteria Isolated from Orthopedic Implants following Revision Hip Surgery

1998 ◽  
Vol 42 (11) ◽  
pp. 3002-3005 ◽  
Author(s):  
Michael M. Tunney ◽  
Gordon Ramage ◽  
Sheila Patrick ◽  
James R. Nixon ◽  
Philip G. Murphy ◽  
...  
Keyword(s):  
Bone Cement ◽  
Antimicrobial Susceptibility ◽  
Antimicrobial Agents ◽  
Orthopedic Implants ◽  
Hip Surgery ◽  
Broth Microdilution ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Revision Hip Surgery

The susceptibilities of 49 isolates recovered from orthopedic implants to seven antimicrobial agents were evaluated by the broth microdilution method. Ciprofloxacin and vancomycin were more active than gentamicin, representing aminoglycosides which are routinely incorporated into bone cement, and also more active than the peroperative antimicrobial agents cefamandole and erythromycin. The use of ciprofloxacin and vancomycin in vivo, therefore, warrants further evaluation.

Tea tree oil: in vitro efficacy in otitis externa

2005 ◽  
Vol 119 (3) ◽  
pp. 198-201 ◽  
Author(s):  
T B Farnan ◽  
J McCallum ◽  
A Awa ◽  
A D Khan ◽  
S J Hall
Keyword(s):  
Otitis Externa ◽  
Inhibitory Concentration ◽  
Tea Tree Oil ◽  
Broth Microdilution ◽  
Melaleuca Alternifolia ◽  
Tea Tree ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Culture And Sensitivity

Objective: The purpose of this study was to determine the susceptibility of organisms causing otitis externa (OE) to the essential oil of Melaleuca alternifolia, or tea tree oil (TTO).Methods: Fifty-seven swabs were taken from the ears of 52 patients with OE for culture and sensitivity. A broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of TTO for each organism.Results: In 51 per cent of the swabs taken, pathogenic organisms were cultured. Of these cultures 71 per cent, both bacteria and yeast, were susceptible to TTO 2 per cent or less. The only organism showing resistance to TTO was Pseudomonas aeruginosa; however 25 per cent of these bacteria were sensitive.Conclusion: Tea tree oil may have a role to play in the treatment of OE. However, more work needs to be done to enhance the anti-pseudomonal effect and to assess ototoxicity.

scholarly journals In Vitro Antibacterial Effect of the Methanolic Extract of the Korean Soybean Fermented Product Doenjang against Staphylococcus aureus

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2319
Author(s):  
Klara Lalouckova ◽  
Lucie Mala ◽  
Petr Marsik ◽  
Eva Skrivanova
Keyword(s):  
Staphylococcus Aureus ◽  
High Performance ◽  
Methanolic Extract ◽  
Bioactive Substances ◽  
Microdilution Method ◽  
Antibacterial Compound ◽  
Fermented Product ◽  
Broth Microdilution Method

Ultra-high performance liquid chromatography/mass spectrometry showed soyasaponin I and the isoflavones daidzein, genistein, and glycitein to be the main components of the methanolic extract of the Korean soybean fermented product doenjang, which is known to be a rich source of naturally occurring bioactive substances, at average contents of 515.40, 236.30, 131.23, and 29.00 ng/mg, respectively. The antimicrobial activity of the methanolic extract of doenjang against nine Staphylococcusaureus strains was determined in vitro by the broth microdilution method to investigate its potential to serve as an alternative antibacterial compound. The results suggest that the extract is an effective antistaphylococcal agent at concentrations of 2048–4096 µg/mL. Moreover, the tested extract also showed the ability to inhibit the growth of both methicillin-sensitive and methicillin-resistant animal and clinical S. aureus isolates. The growth kinetics of the chosen strains of S. aureus at the minimum inhibitory concentration of the methanolic extract of doenjang support the idea that the tested extract acts as an antibacterial compound. To the best of our knowledge, this is the first report on the antistaphylococcal action of the methanolic extract of doenjang thus, additional studies including in vivo testing are necessary to confirm this hypothesis.

scholarly journals In Vitro Activities of Voriconazole in Combination with Three Other Antifungal Agents against Candida glabrata

2004 ◽  
Vol 48 (9) ◽  
pp. 3317-3322 ◽  
Author(s):  
Francesco Barchiesi ◽  
Elisabetta Spreghini ◽  
Monia Maracci ◽  
Annette W. Fothergill ◽  
Isabella Baldassarri ◽  
...  
Keyword(s):  
Candida Glabrata ◽  
Antifungal Agents ◽  
Beneficial Effects ◽  
Synergistic Interactions ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Disk Diffusion Assay ◽  
Combination Regimens

ABSTRACT Candida glabrata has recently emerged as a significant pathogen involved in both superficial and deep-seated infections. In the present study, a checkerboard broth microdilution method was performed to investigate the in vitro activities of voriconazole (VOR) in combination with terbinafine (TRB), amphotericin B (AMB), and flucytosine (5FC) against 20 clinical isolates of C. glabrata. Synergy, defined as a fractional inhibitory concentration (FIC) index of ≤0.50, was observed in 75% of VOR-TRB, 10% of VOR-AMB, and 5% of VOR-5FC interactions. None of these combinations yielded antagonistic interactions (FIC index > 4). When synergy was not achieved, there was still a decrease in the MIC of one or both drugs used in the combination. In particular, the MICs were reduced to ≤1.0 μg/ml as a result of the combination for all isolates for which the AMB MIC at the baseline was ≥2.0 μg/ml. By a disk diffusion assay, the halo diameters produced by antifungal agents in combination were greater that those produced by each drug alone. Finally, killing curves showed that VOR-AMB exhibited synergistic interactions, while VOR-5FC sustained fungicidal activities against C. glabrata. These studies demonstrate that the in vitro activity of VOR against this important yeast pathogen can be enhanced upon combination with other drugs that have different modes of action or that target a different step in the ergosterol pathway. Further studies are warranted to elucidate the potential beneficial effects of such combination regimens in vivo.

scholarly journals Prevalence of Antimicrobial Resistance among Clinical Isolates of Bacteroides fragilis Group in Canada in 2010-2011: CANWARD Surveillance Study

2011 ◽  
Vol 56 (3) ◽  
pp. 1247-1252 ◽  
Author(s):  
James A. Karlowsky ◽  
Andrew J. Walkty ◽  
Heather J. Adam ◽  
Melanie R. Baxter ◽  
Daryl J. Hoban ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
Bacteroides Fragilis ◽  
Clinical Isolates ◽  
Surveillance Study ◽  
Content Type ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Amoxicillin Clavulanate ◽  
Bacteroides Fragilis Group ◽  
Bacteroides Ovatus

ABSTRACTClinical isolates of theBacteroides fragilisgroup (n= 387) were collected from patients attending nine Canadian hospitals in 2010-2011 and tested for susceptibility to 10 antimicrobial agents using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method.B. fragilis(59.9%),Bacteroides ovatus(16.3%), andBacteroides thetaiotaomicron(12.7%) accounted for ∼90% of isolates collected. Overall rates of percent susceptibility were as follows: 99.7%, metronidazole; 99.5%, piperacillin-tazobactam; 99.2%, imipenem; 97.7%, ertapenem; 92.0%, doripenem; 87.3%, amoxicillin-clavulanate; 80.9%, tigecycline; 65.9%, cefoxitin; 55.6%, moxifloxacin; and 52.2%, clindamycin. Percent susceptibility to cefoxitin, clindamycin, and moxifloxacin was lowest forB. thetaiotaomicron(n= 49, 24.5%),Parabacteroides distasonis/P. merdae(n= 11, 9.1%), andB. ovatus(n= 63, 31.8%), respectively. One isolate (B. thetaiotaomicron) was resistant to metronidazole, and two isolates (bothB. fragilis) were resistant to both piperacillin-tazobactam and imipenem. Since the last published surveillance study describing Canadian isolates ofB. fragilisgroup almost 20 years ago (A.-M. Bourgault et al., Antimicrob. Agents Chemother. 36:343–347, 1992), rates of resistance have increased for amoxicillin-clavulanate, from 0.8% (1992) to 6.2% (2010-2011), and for clindamycin, from 9% (1992) to 34.1% (2010-2011).

scholarly journals Emprego do óleo de Melaleuca alternifolia Cheel (Myrtaceae) na odontologia: perspectivas quanto à utilização como antimicrobiano alternativo às doenças infecciosas de origem bucal

2011 ◽  
Vol 13 (4) ◽  
pp. 492-499 ◽  
Author(s):  
A.C.M. Oliveira ◽  
A. Fontana ◽  
T.C. Negrini ◽  
M.N.M. Nogueira ◽  
T.B.L. Bedran ◽  
...  
Keyword(s):  
Tea Tree Oil ◽  
Melaleuca Alternifolia ◽  
Tea Tree

O interesse por medicamentos alternativos, principalmente daqueles provenientes de extratos naturais, tem aumentado nas últimas décadas. A Melaleuca alternifolia é um arbusto pertencente ao gênero Melaleuca, popularmente conhecida como "árvore de chá", cujo principal produto é o óleo essencial (TTO - tea tree oil), de grande importância medicinal por possuir comprovada ação bactericida e antifúngica contra diversos patógenos humanos. Em virtude da atividade terapêutica em diversas especialidades médicas, o TTO passou a ser empregado na área odontológica. Esta revisão de literatura foi realizada com o objetivo de discutir os ensaios já realizados com o TTO contra microrganismos relacionados à doença cárie, doença periodontal e problemas pulpares. O óleo de Melaleuca tem demonstrado boa ação antibacteriana in vitro contra microrganismos bucais, porém, pesquisas envolvendo o estudo do mecanismo de ação sobre as células microbianas ou estudos in vivo ainda são escassos e precisam ser realizados, já que esse produto pode ser útil na odontologia, seja na manutenção química da higiene ou prevenção de doenças bucais.

scholarly journals Correlation of In Vitro Activity, Serum Levels, and In Vivo Efficacy of Posaconazole against Rhizopus microsporus in a Murine Disseminated Infection

2009 ◽  
Vol 53 (12) ◽  
pp. 5022-5025 ◽  
Author(s):  
M. Mar Rodríguez ◽  
F. Javier Pastor ◽  
Enrique Calvo ◽  
Valentina Salas ◽  
Deanna A. Sutton ◽  
...  
Keyword(s):  
Serum Levels ◽  
Rhizopus Microsporus ◽  
In Vitro Susceptibility ◽  
In Vivo Efficacy ◽  
Susceptibility Data ◽  
Microdilution Method ◽  
Drug Concentrations ◽  
Broth Microdilution Method

ABSTRACT A broth microdilution method was used to evaluate the in vitro activities of seven antifungal agents against 15 clinical strains of Rhizopus microsporus. Amphotericin B (AMB) and posaconazole (POS) were the most active drugs. In a model of disseminated R. microsporus infection in immunosuppressed mice, we studied the efficacy of POS administered once or twice daily against four of the strains previously tested in vitro and compared it with that of liposomal AMB (LAMB). LAMB was the most effective treatment for the two strains with intermediate susceptibility to POS. For the two POS-susceptible strains, LAMB and POS at 20 mg/kg of body weight twice a day orally showed similar efficacies. The in vivo efficacy of POS administered twice a day orally correlated with the in vitro susceptibility data and the serum drug concentrations.

In vitro activity of antimicrobial agents with and without sulbactam, EDTA and sulbactam-EDTA on ESBLs-producing Escherichia coli isolated from healthy Tibetan yaks

2020 ◽  
Author(s):  
Baoguang Liu ◽  
Xiaoling Yuan ◽  
Yiheng Chen ◽  
Xiaoshen Li ◽  
Ming Bai ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Nasal Swab ◽  
Antimicrobial Agents ◽  
Synergistic Effects ◽  
E Coli ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Third Generation Cephalosporins ◽  
Enhance Activity

Abstract Background The spread of ESBLs-producing bacteria has been strikingly rapid in many regions of the world and it causes therapeutic difficulties in everyday practice. The aims of this study were to investigate the prevalence and susceptibilities of ESBLs-producing Escherichia coli isolates from healthy Tibetan yaks in China, to evaluate the activity of drug combinations on ESBLs-producing E. coli isolates. Methods From July 2018 to August 2019, a total of 750 nasal swab samples were tested for the presence of E. coli and ESBLs-producing strains. The MICs of 11 antimicrobial agents alone and combinations with sulbactam, EDTA or sulbactam-EDTA against 240 ESBLs-producing E.coli strains were determined by the broth microdilution method. Results Overall, 59.87% (n = 449) of the samples were positive for E. coli, 240 (53.45%) of 449 E. coli isolates were confirmed to be ESBLs-producing. The addition of sulbactam to the third generation cephalosporins, amikacin and fosfomycin for all isolates resulted in low MICs, increasing the level of susceptibility from 0, 0 and 0% to 50 ~ 87.5, 4.2 and 100% respectively. The addition of EDTA to fluoroquinolones, doxycycline, florfenicol, amikacin and fosfomycin, showed improved activities and resulted in low MICs, increasing the level of susceptibility from 0, 0, 8.3, 0 and 0% to 4.2 ~ 29.2, 33.3, 33.3, 66.7 and 45.8%, respectively. All other antibacterials (except fluoroquinolones, doxycycline and florfenicol), when combined with sulbactam-EDTA, were found to be more active than combinations only with sulbactam or with EDTA against most of isolates, with lower MIC50s and MIC90s. Conclusion In conclusion, ESBLs-producing E. coli isolates were widespread in healthy Tibetan yaks in China. ESBLs-producing E. coli isolates exhibited varying degrees of multidrug resistance. This study these findings suggested that sulbactam can enhance activity of β-lactams and some non-β-lactams of antimicrobial agents and had a synergistic effects with EDTA in improving activities of some families of antimicrobials.

Sign in / Sign up

Export Citation Format

Share Document