Antifungal and post-antifungal effects of chlorhexidine, fluconazole, chitosan and its combinations on Candida albicans

Abstract

Objective: The aim of this work was to assess the antifungal and post-antifungal effects of chlorhexidine, fluconazole, chitosan and its combinations on virulence factors of Candida albicans. Study Design: Ten isolated strains of Candida albicans obtained from 10 patients with oral candidiasis and a collection strain of C. albicans were treated with antifungal agents in different concentrations or combinations of them. Virulence factors analyzed were the cell surface hydrophobicity, the germinative tube development, the phospholipase activity and the post-antifungal effect of that exposure. Results: Virulence factors of the isolated strains obtained from patients together with the collection strain showed significant decreases with the different antifungal treatments, except for hydrophobicity and phospholipase activity. The development of germinative tube was the most sensitive factor to all the antifungal agents used. Untreated strains as well as the ones treated with antifungal agents showed a positive correlation among the virulence factors analyzed. No synergic effects arose from the combinations of the used drugs. Conclusions: C. albicans isolated strains from patients showed high phospholipase activity and germinative tube production, which corroborates their capacity to infect the oral mucosa and the high prevalence of species. As a whole, our results imply that short exposures to sub-inhibitory concentrations of the antifungal agents under analysis, isolated or combined, can modulate the way virulence factors get manifested, thus decreasing their pathogenicity.

The postantifungal effect and phospholipase production of oral Candida albicans from smokers, diabetics, asthmatics, denture wearers and healthy individuals following brief exposure to subtherapeutic concentrations of chlorhexidine gluconate

“…Chlorhexidine gluconate 0.2% (Glaxo Smith Kline, Brentford, UK) was dissolved in sterile phosphate‐buffered saline (PBS) at pH 7.2 and was prepared as 0.005%, 0.0025% and 0.00125% solutions immediately prior to each experiment as previously described …”

“…In addition, a recent study has shown that subtherapeutic levels of CG are also effective in suppressing germ tube (GT) formation of oral C. albicans isolates obtained from healthy as well as diabetics, asthmatics using steroid inhalers and smokers . Furthermore, it has been shown that CG alone or in combination with other antimycotic agents were capable of inducing a PAFE as well as modulating virulent attributes of Candida including phospholipase production . For these reasons, oral rinses containing CG may be an appropriate substitute to conventional antimycotics in the management of oral candidosis …”

Amphotericin B-Induced in vitro Postantifungal Effect on <b><i>Candida</i></b> Species of Oral Origin

“…In addition, the current study indicates that the antifungal activity of amphotericin B may probably be realized even when administered at extended intervals due to the PAFE elicited by this drug. However, since the PAFE depends upon the organism in question, the concentration, exposure time and mode of action of the tested drug and other environmental factors [11,16,17,18], further studies with a larger battery of organisms are needed to determine the relationship between the PAFE of amphotericin B and its dosage regimen applicable in vivo.…”

Use of chitosan mouth-wash in radio-chemotherapy induced oral mucositis: A case-control study

“…The anti-fungal activity if Chitosan is through permeabilization of yeast cells and efflux of potassium ions, along with an increased uptake of calcium ions, and inhibition of respiration, fermentation, and viability of the cells. [17] A study [18] was done to assess the antifungal and post-antifungal effects of chlorhexidine, fluconazole, chitosan and its combinations on Candida albicans in patients with OM and chitosan was found to be effective to inhibit the concentrations of Candida. Chitosan is a bio-adhesive or a mucoadhesive polymer and forms an occlusive dressing over the mucosa which inhibits the settling of secondary infection and also aids in the protection of the wound from secondary injuries.…”