scholarly journals The European Confederation of Medical Mycology (ECMM) survey of candidaemia in Italy: in vitro susceptibility of 375 Candida albicans isolates and biofilm production

2005 ◽  
Vol 56 (4) ◽  
pp. 777-779 ◽  
Author(s):  
Anna Maria Tortorano ◽  
Anna Prigitano ◽  
Emanuela Biraghi ◽  
Maria Anna Viviani
Keyword(s):  
Candida Albicans ◽  
Medical Mycology ◽  
In Vitro Susceptibility ◽  
Biofilm Production

scholarly journals Effect of fluconazole on viability of Candida albicans over extended periods of time.

1996 ◽  
Vol 40 (11) ◽  
pp. 2622-2625 ◽  
Author(s):  
P G Sohnle ◽  
B L Hahn ◽  
M D Erdmann
Keyword(s):  
Candida Albicans ◽  
Marked Reduction ◽  
Culture Medium ◽  
Antimicrobial Agents ◽  
Yeast Cells ◽  
In Vitro Susceptibility ◽  
Fungistatic Activity ◽  
Susceptibility Tests ◽  
Infecting Organisms

The treatment of chronic mycoses may expose the infecting organisms to antimicrobial agents for extended periods of time. It is possible that an azole antifungal drug such as fluconazole, with primarily fungistatic activity in standard in vitro susceptibility tests, might be able to damage the fungal cells and reduce their viability over prolonged incubations under nonproliferating conditions. To test this possibility, Candida albicans yeast cells were exposed to various concentrations of fluconazole in RPMI 1640 tissue culture medium for 4 h at 37 degrees C, washed free of the drug, and then incubated at 37 degrees C for a 28-day period; enumeration of the remaining CFU at various times during this period revealed no increased loss of viability for the fluconazole-exposed organisms. However, when fluconazole was added to the organisms maintained in distilled water (with or without pretreatment with the drug), a marked reduction of viability was found. At 14 days of incubation with two strains of C. albicans, negative cultures were found for 7 of 10 and 10 of 11 samples, respectively, containing 1.0 microgram of fluconazole per ml versus 0 of 10 and 1 of 11 control samples (P of < 0.01 and 0.001, respectively). The effect of fluconazole on fungal viability under these conditions became noticeable at approximately 7 days and was greater when the samples were incubated at 37 degrees C rather than 25 degrees C. These findings suggest that fluconazole may have fungicidal effects on fungal cells during prolonged exposures under conditions in which the organisms are prevented from proliferating by lack of nutrients.

Increase in the in vitro susceptibility of Staphylococcus aureus to antimicrobial agents in the presence of Candida albicans

1979 ◽  
Vol 25 (4) ◽  
pp. 429-435 ◽  
Author(s):  
J. deRepentigny ◽  
R. Lévesque ◽  
L. G. Mathieu
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Candida Albicans ◽  
Inhibitory Activity ◽  
Antimicrobial Agents ◽  
Mixed Cultures ◽  
Alpha Toxin ◽  
In Vitro Susceptibility ◽  
Pure Cultures

In experiments with mixed cultures of Staphylococcus aureus and Candida albicans both in the absence and in the presence of 5-fluorocytosine (5-FC), we have observed that (1) there is an inhibition of S. aureus growth in mixed cultures with C. albicans in media supplemented with 1 μg/mL of 5-FC and that 5-FC has no effect on staphylococci in pure cultures; (2) this inhibition occurred with clinically isolated and laboratory strains and could be reversed by specific metabolites; (3) Staphylococcus aureus was inhibited by filtrates of C. albicans cultures treated with 5-FC and this seemed to be favored by some C. albicans filterable product which can affect the cell wall and the permeability of the staphylococcal cells since they become sensitive to 5-FC; (4) nine other commonly used antimicrobials showed an increased inhibitory activity against S. aureus in mixed cultures with C. albicans; and (5) there is a decrease in the number of precipitating antigens of S. aureus and of the activity of alpha toxin when this species was grown with both C. albicans and 5-FC. Our results indicate that the susceptibility of some species to antimicrobials could be significantly modified in the presence of other species. One cannot exclude that a similar phenomenon could happen in hosts under treatment with antibiotics against infection.

In vitro susceptibility of Candida albicans, Austria 1992

Mycoses ◽  
2009 ◽  
Vol 36 (11-12) ◽  
pp. 411-416 ◽  
Author(s):  
F. Allerberger ◽  
A. Fassl ◽  
D. Niederwieser ◽  
R. Zangerle ◽  
W. Lingnau ◽  
...  
Keyword(s):  
Candida Albicans ◽  
In Vitro Susceptibility

scholarly journals Comparative resistance of Candida albicans clinical isolates to fluconazole and itraconazole in vitro and in vivo in a murine model.

1996 ◽  
Vol 40 (6) ◽  
pp. 1342-1345 ◽  
Author(s):  
A Valentin ◽  
R Le Guennec ◽  
E Rodriguez ◽  
J Reynes ◽  
M Mallie ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Murine Model ◽  
Survival Rates ◽  
Drug Regimen ◽  
Clinical Isolates ◽  
In Vitro Susceptibility ◽  
Microdilution Method ◽  
Broth Microdilution Method

Relationships between azole susceptibility and in vivo response to antifungal therapy in a murine model of candidiasis were investigated for Candida albicans isolates sampled from human immunodeficiency virus type 1-positive patients with oropharyngeal candidiasis. The susceptibilities of seven clinical isolates and two reference strains to fluconazole (FCZ) and itraconazole (ITZ) were determined in vitro by the broth microdilution method. Four isolates were resistant to FCZ and ITZ, two were susceptible to both azoles, and three were resistant to FCZ and susceptible to ITZ (dissociated resistance). CD1 mice were inoculated with each isolate and treated with either FCZ or ITZ (drug regimen, 5 mg/kg of body weight twice daily for 5 days). Quantitative cultures of kidneys were performed at the end of the treatment. On the other hand, the survival rates of the mice were followed daily. These two parameters were clearly correlated with in vitro susceptibility. Thus, the phenomenon of a dissociation of resistance to FCZ and ITZ may be found in vivo as well as in vitro.

scholarly journals Effect of Prolonged Fluconazole Treatment on Candida albicans in Diffusion Chambers Implanted into Mice

2002 ◽  
Vol 46 (10) ◽  
pp. 3175-3179
Author(s):  
Peter G. Sohnle ◽  
Beth L. Hahn
Keyword(s):  
Candida Albicans ◽  
Inflammatory Response ◽  
Inflammatory Cells ◽  
Model System ◽  
Antifungal Drugs ◽  
Yeast Cells ◽  
In Vitro Susceptibility ◽  
Bonferroni Test

ABSTRACT Fluconazole is an azole agent with primarily fungistatic activity in standard in vitro susceptibility tests. The present study was undertaken to develop a diffusion chamber model system in mice in order to study the in vivo effects of prolonged fluconazole treatment on Candida albicans. Chambers containing 100 C. albicans yeast cells were implanted subcutaneously on the flanks of C57BL/6 mice and were then retrieved 6 or 14 weeks later (after fluconazole treatment for 4 or 12 weeks, respectively). Leukocyte counts demonstrated that implantation of the chambers did elicit an inflammatory response but that only small numbers of inflammatory cells were able to enter the chamber interior. Treatment with fluconazole at 10 mg/kg of body weight/day for 12 weeks not only reduced the numbers of viable organisms within the chambers compared to those in untreated mice (mean ± standard deviation of log10 CFU of 0.7 ± 1.2 versus 2.3 ± 2.0; P < 0.001 by the Bonferroni test) but also increased the numbers of chambers that became sterile over the treatment period (14 of 16 versus 6 of 19; P = 0.0009 by the chi-square test). However, treatment for only 4 weeks had minimal effects on the numbers of chamber CFU, and none of the chambers became sterile during this period. Distribution of retrieved organisms between interior fluid and the chamber filters was approximately equal in all the treatment groups. This model system appears to be useful for evaluating the effects of antifungal drugs over prolonged periods in vivo. Its use in the present study demonstrates that fluconazole can increase the rate of sterilization of C. albicans foci that are protected from the host's inflammatory response.

scholarly journals Fluconazole treatment of Candida albicans infection in mice: does in vitro susceptibility predict in vivo response?

1995 ◽  
Vol 39 (10) ◽  
pp. 2197-2200 ◽  
Author(s):  
J. R. Graybill ◽  
L. K. Najvar ◽  
J. D. Holmberg ◽  
A. Correa ◽  
M. F. Luther
Keyword(s):  
Candida Albicans ◽  
In Vitro Susceptibility ◽  
Candida Albicans Infection

Activity of Metal-Azole Complexes Against Biofilms of Candida albicans and Candida glabrata

2020 ◽  
Vol 26 (14) ◽  
pp. 1524-1531 ◽  
Author(s):  
Livia D. Pereira ◽  
Taissa Vila ◽  
Luana P. Borba-Santos ◽  
Wanderley de Souza ◽  
Maribel Navarro ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Biofilm Formation ◽  
Candida Glabrata ◽  
Ex Vivo ◽  
Drug Efficacy ◽  
Ex Vivo Model ◽  
In Vitro Susceptibility ◽  
Poor Patient Compliance ◽  
Nail Infection

Background: Onychomycosis is a chronic nail infection caused by fungi frequently resistant to antifungal treatments. Recalcitrance in nail infections is a result of reduced antifungal penetration due to biofilm formation, combined with poor patient compliance with the treatment, which can be as long as 18 months. Objective: Metal-drug complexation is a widely used strategy to increase drug efficacy. Therefore, the aim of this work was to evaluate the antifungal and anti-biofilm activity of several metal-azole complexes against Candida albicans and Candida glabrata. Methods: Susceptibility assays and scanning electron microscopy were performed to determine the anti-biofilm activity of eight metal-azole complexes in vitro and ex-vivo, using human nail fragments. Results: In vitro susceptibility assays showed that complexation of both Au(I) and Zn(II) to clotrimazole and ketoconazole improved the anti-biofilm activity compared to the azole alone. Using an ex-vivo model of biofilm formation on fragments of human nails, we also demonstrate the improved efficacy of metal-azole complexes against biofilms of C. albicans and C. glabrata that resembles the onychomycosis structure. Noteworthy, biofilms of C. glabrata were more susceptible to the optimized complexes than those of C. albicans. Conclusion: In conclusion, metal-azole complexes used in this work show promising anti-biofilm activity and further clinical studies should confirm its potential for the treatment of Candida-associated onychomycosis.

scholarly journals In vitro susceptibility of oral Candida albicans strains to different pH levels and calcium hydroxide saturated aqueous solution

2012 ◽  
Vol 23 (3) ◽  
pp. 192-198 ◽  
Author(s):  
Paulo Henrique Weckwerth ◽  
Cristiane Carnietto ◽  
Ana Carolina Villas Boas Weckwerth ◽  
Marco Antonio Hungaro Duarte ◽  
Milton Carlos Kuga ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Candida Albicans ◽  
Oral Cavity ◽  
Calcium Hydroxide ◽  
Culture Broth ◽  
Saturated Aqueous Solution ◽  
Chi Square ◽  
Agar Culture ◽  
In Vitro Susceptibility

Candida albicans is present in the oral cavity and in the whole digestive tract of humans and other animals, being frequently related to endodontic treatment failure. The present study determined the incidence of C. albicans in the oral cavity and the susceptibility of isolates to different pH values and saturated calcium hydroxide aqueous solution at pH 12.5. Sixty-five patients attending the Endodontic Clinic at the Sagrado Coração University participated in the study. The collected samples were cultivated in selective media for C. albicans and the isolates were tested in terms of resistance to both alkaline pH and saturated aqueous solution of calcium hydroxide. In relation to time variables, yeast viability was assessed by the Sabouraud's agar culture and fluorescein diacetate and ethidium bromide fluorescent staining method. Results from the different pHs and experimental times, including those from different techniques measuring fungal viability, were compared using the chi-square and Fisher's exact tests (α=0.05). The yeasts became completely inviable after 48 h of contact with the calcium hydroxide solution. On the other hand, when exposed to the alkaline culture broth, the yeasts were found to be viable at pHs 9.5 and 10.5 for up to 7 days. In conclusion, C. albicans can only be completely inhibited by direct contact with saturated calcium hydroxide aqueous solution after 48 h of exposure.

scholarly journals Susceptibility to antifungal agents of Candida spp. from blood and feces collected in Novi Sad in 3-year period (2008-2010)

2011 ◽  
pp. 19-26
Author(s):  
Zora Jelesic ◽  
Deana Medic ◽  
Mira Mihajlovic-Ukropina ◽  
Marija Jevtic ◽  
Vera Gusman ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Antifungal Agents ◽  
Antifungal Susceptibility ◽  
Empiric Therapy ◽  
Invasive Disease ◽  
Candida Spp ◽  
In Vitro Susceptibility ◽  
The Right ◽  
Novi Sad

Candidemia is an important emerging nosocomial infection in patients with risk factors. Candida species from nonsterile sites can give insight into the characteristics of strains that may cause invasive disease. The aim of this study was to evaluate antifungal susceptibility of Candida blood and fecal isolates in Novi Sad, Vojvodina. During a 3-year period (2008 to 2010), 424 isolates of Candida spp. were collected, 30 bloodstream isolates and 394 strains from fecal samples. In vitro susceptibility of these isolates to five antifungal agents was established using commercial ATB FUNGUS 3 (Bio-M?rieux). Predominant species was Candida albicans (6 isolates from blood and 269 from feces). Resistance to one or more antifungal agents was less common in Candida albicans (3.63%) than in other species (24.83%). Resistance to itraconazole was the most commonly found in both groups of isolates, 9.64% strains from feces and 20% from blood samples. Twelve isolates were multiply resistant, usually to fluconazole, itraconazole, and voriconazole. Resistance to amphotericine B was extremely rare. Although resistance to antimycotics of Candida spp. is rare at present, continued surveillance of antifungal susceptibility is necessary in order to monitor trends, and to choose the right empiric therapy.

Sign in / Sign up

Export Citation Format

Share Document