agar and Candidiasis--Oral

Overgrowth of Candida yeasts in the oral cavity may result in the development of oral thrush in immunocompromised individuals. This study analyzed the diversity and richness of the oral mycobiota of patients clinically diagnosed with oral thrush (OT), follow-up of oral thrush patients after antifungal therapy (AT), and healthy controls (HC). Oral rinse and oral swab samples were collected from 38 OT patients, 21 AT patients, and 41 healthy individuals (HC). Pellet from the oral rinse and oral swab were used for the isolation of oral Candida yeasts on Brilliance Candida Agar followed by molecular speciation. ITS1 amplicon sequencing using Illumina MiSeq was performed on DNA extracted from the oral rinse pellet of 16 OT, 7 AT, and 7 HC oral rinse samples. Trimmed sequence data were taxonomically grouped and analyzed using the CLC Microbial Genomics Module workflow. Candida yeasts were isolated at significantly higher rates from oral rinse and swab samples of OT (68.4%, p < 0.001) and AT (61.9%, p = 0.012) patients, as compared to HC (26.8%). Predominance of Candida albicans specifically, was noted in OT (60.5%, p < 0.001) and AT (42.9%, p = 0.006) vs. HC (9.8%), while non-albicans Candida species was dominant in HC. Analysis of oral mycobiota from OT patients showed the presence of 8 phyla, 222 genera, and 309 fungal species. Low alpha diversity (Shannon index, p = 0.006; Chao-1 biased corrected index, p = 0.01), varied beta diversity (Bray-Curtis, p = 0.01986; Jaccard, p = 0.02766; Weighted UniFrac, p = 0.00528), and increased relative abundance of C. albicans (p = 3.18E-02) was significantly associated with the oral mycobiota of OT vs. HC. This study supported that C. albicans is the main etiological agent in oral thrush and highlights the association of fungal biodiversity with the pathophysiology of oral thrush.

Topics: Agar; Antifungal Agents; Candida; Candida albicans; Candidiasis, Oral; Humans

In the recent decade, the increased immunocompromised population such as diabetic patients makes a high incidence of invasive. A total of 108. This study showed that most of the isolates had different enzymatic patterns, and

Topics: Agar; Candida albicans; Candidiasis, Oral; Diabetes Complications; Diabetes Mellitus; Egg Yolk; Hemolysin Proteins; Hemolysis; Humans; Mouth; Mouth Mucosa; Phospholipases; Polysorbates; Risk Factors; Species Specificity; Virulence; Virulence Factors

Ciclopirox olamine (CPO) is a topical wide-spectrum antimycotic agent that possesses antifungal, antibacterial and anti-inflammatory activities. Loading CPO into a hybridized vesicular system is expected to enhance its buccal permeation and hence, therapeutic activity, whereas the frequent administration and side effects are reduced. Vesicular systems with high penetration ability were prepared based on cholesterol, Lipoid S45 or Phospholipon 90H, with span 60 while incorporating a penetration enhancer (Labrafac or labrasol) followed by full assessment of their size, entrapment efficiency, and drug release profiles. The optimum formulation, composed of Lipoid S45 and Labrafac, possessed the smallest vesicle size (346.1 nm), highest entrapment efficiency (94.4%), and sustained CPO release pattern, and was characterized for its morphology and thermal properties. This powerful mixture of the penetration enhancers (Lipoid S45 and Labrafac) in the designed hybridized vesicles was thoroughly investigated for their characteristics after being incorporated in bioadhesive gel. Moreover, enhanced antifungal activity was demonstrated either upon testing the designed formulation on agar plates or in vivo upon treating infected rabbits with the proposed formulation. Results suggest that the presented bioadhesive gel incorporating the CPO-loaded vesicles can be a promising delivery system that can offer a prolonged localized antifungal treatment with enhanced therapeutic effect.

Topics: Adhesives; Administration, Buccal; Agar; Animals; Antifungal Agents; Candidiasis, Oral; Cholesterol; Ciclopirox; Drug Compounding; Drug Liberation; Excipients; Nanoparticles; Particle Size; Rabbits; Rheology

CHROMagar has been reported to be useful for the rapid and accurate identification of Candida species. We tested 135 isolates of Candida species isolated from oropharyngeal candidiasis in HIV patients and found that it was useful in the presumptive identification of Candida albicans and Candida krusei. Occasional strains of C. tropicalis produced colonies with a greenish tinge making it difficult to differentiate from C. albicans.

Topics: Agar; Candida; Candidiasis, Oral; Chromogenic Compounds; Culture Media; HIV Infections; Humans; Mycological Typing Techniques; Sensitivity and Specificity

Candida glabrata switches spontaneously at high frequency among the following four graded phenotypes discriminated on agar containing 1 mM CuSO(4): white, light brown, dark brown (DB), and very dark brown. C. glabrata also contains three mating type loci with a configuration similar to that of the Saccharomyces cerevisiae mating type cassette system, suggesting it may also undergo cassette switching at the expression locus MTL1. To analyze both reversible, high-frequency phenotypic switching and mating type switching at sites of colonization, primary samples from the oral cavities and vaginal canals of three patients suffering from C. glabrata vaginitis were clonally plated on agar containing CuSO(4). It was demonstrated that (i) in each vaginitis patient, there was only one colonizing strain; (ii) an individual could have vaginal colonization without oral colonization; (iii) phenotypic switching occurred at sites of colonization; (iv) the DB phenotype predominated at the site of infection in all three patients; (v) genetically unrelated strains switched in similar, but not identical, fashions and caused vaginal infection; (vi) different switch phenotypes of the same strain could simultaneously dominate different body locations in the same host; (vii) pathogenesis could be caused by cells in different mating type classes; and (viii) mating type switching demonstrated at both the genetic and transcription levels occurred in one host.

Topics: Agar; Candida glabrata; Candidiasis, Oral; Candidiasis, Vulvovaginal; Culture Media; DNA Fingerprinting; Female; Fungal Proteins; Gene Expression Regulation, Fungal; Genes, Fungal; Genes, Mating Type, Fungal; Humans; Mouth; Phenotype; Vagina

Candida dubliniensis, an emerging oral pathogen, phenotypically resembles Candida albicans so closely that it is easily misidentified as such. The aim of the present study was to evaluate the usefulness of two phenotypic methods, growth at 45 degrees C and 2,3,5-triphenyltetrazolium chloride (TTC) reduction, for confirming presumptive identification of C. dubliniensis and C. albicans by colony color on CHROMagar Candida (CAC) medium. A combination of these methods was used to establish the prevalence of oral C. dubliniensis in an Italian population of 45 human immunodeficiency virus (HIV)-infected subjects. Twenty-two samples (48.9%) were positive for yeasts on CAC medium producing a total of 37 fungal isolates. The colony color and 45 degrees C growth ability test correctly identified all C. dubliniensis and C. albicans isolates (5/37, 13.5%, and 16/37, 43.2%, respectively), while assessment of TTC reduction misidentified one C. albicans isolate. The isolation rate of C. dubliniensis was 11.1% (5/45 patients). All of the C. dubliniensis isolates were highly susceptible to fluconazole (MIC = 0.5 microg/ml). The combination of CAC medium screening with growth at 45 degrees C and TTC reduction tests may represent a simple, reliable and inexpensive identification protocol for C. dubliniensis.

Topics: Adult; Agar; Antifungal Agents; Candida; Candida albicans; Candidiasis, Oral; Chromogenic Compounds; Colony Count, Microbial; Coloring Agents; Culture Media; DNA, Fungal; Drug Resistance, Fungal; Female; Fluconazole; HIV Infections; Humans; Italy; Male; Middle Aged; Mouth; Phenotype; Polymerase Chain Reaction; Temperature; Tetrazolium Salts

Candida albicans normally produces blastoconidia measuring 2 to 8 microns in diameter. Markedly enlarged "giant" (approximately 30 microns) blastoconidia of a C. albicans isolate (designated BH) were observed after growth on commercially prepared chocolate agar already supplemented with IsoVitalex (BBL-Microbiology Systems, Cockeysville, MD, USA). Morphologically, "giant" blastoconidia presented a spectrum of forms such as blastoconidia with linear creases, with a single broad-based bud resembling Blastomyces dermatididis, with multiple buds resembling Paracoccidioides brasiliensis, or elliptical in shape. "Giant" blastoconidia contained a large oval clear vacuole occupying greater than 50% of the blastoconidium. Pseudohyphae emanating from these blastoconidia were also enlarged and contained a similar oval inclusion. Rarely observed were "giant" blastoconidia with either adherent or internalized blastoconidia uniformly arranged within the blastoconidium. "Giant" or enlarged blastoconidia production was constant, usually approaching 10 to 20% of the blastoconidial units comprising a single colony, irrespective of the number of subcultures. IsoVitalex supplementation of Remel (Lexana, KS, USA) chocolate agar but not a variety of other media also resulted in "giant" blastoconidia production. It is, therefore, theorized that a component(s) of IsoVitalex activates/blocks a gene present in select clones of C. albicans blastoconidia resulting in "giant" or enlarged blastoconidiogenesis.

Topics: Agar; Candida albicans; Candidiasis, Oral; Culture Media; Humans; Infant; Microscopy, Phase-Contrast; Pharynx

The purpose of this study was to examine the effect of preceding fluconazole treatment on the oral mycologic flora and on the sensitivity of oral Candida albicans isolates to fluconazole. Saline oral rinses were collected from 89 HIV-positive patients, of whom 48 had been exposed to fluconazole and 41 were fluconazole-naive. The rinses were cultured on Sabouraud's and Pagano Levin agars, and yeasts were identified by standard methods. Fluconazole sensitivity of C. albicans isolates was measured by disk diffusion assay. C. albicans was isolated from 69% of patients who had received fluconazole and from 93% of the patients who were fluconazole-naive (p < 0.05). Nine other species of yeasts were also isolated, most commonly C. glabrata. Five patients previously exposed to fluconazole harbored fluconazole-resistant C. albicans, whereas no resistance was detected among the patients who were fluconazole-naive (p < 0.01). Sixteen of the patients who were fluconazole-exposed carried yeasts other than C. albicans, compared with only five patients in the fluconazole-naive group (p < 0.01). All of the fluconazole-resistant strains were isolated from patients with low CD4 counts (less than 100 cells/ml) and after lengthy fluconazole exposures. Nevertheless, patients in Charlotte, N.C., who had a greater mean fluconazole exposure time (10.25 +/- 1.41 months) than patients in Glasgow, UK, (0.65 +/- 0.18 months; p < 0.005), did not develop significantly more in vitro resistance or species diversity. This study indicates that long-term fluconazole treatment can have significant effects on the yeast flora of the mouth, particularly in a patient with a CD4 count of less than 100 cells/ml.

Topics: Adult; Agar; Antifungal Agents; Candida; Candida albicans; Candidiasis, Oral; CD4 Lymphocyte Count; Colony Count, Microbial; Culture Media; Drug Resistance, Microbial; Female; Fluconazole; HIV Seropositivity; Humans; Male; Mouth; Pichia

A method for detecting fluconazole-resistant yeasts was developed that uses chromogenic agar containing fluconazole. Yeasts were plated on media with fluconazole at 0, 8, and 16 micrograms/ml. On media without fluconazole, normal growth of susceptible yeasts (defined as those having a fluconazole MIC of < 8 micrograms/ml) was detected, while fluconazole-containing media suppressed susceptible strains and normal colonies of resistant yeasts (fluconazole MICs of > or = 8 micrograms/ml) were detected. This method was used to screen for resistance in oropharyngeal candidiasis. Isolates having fluconazole MICs of > or = 8 micrograms/ml and < 8 micrograms/ml were correctly predicted in 43 of 45 cultures and 115 of 116 cultures, respectively. This screening method appears to be rapid and sensitive for detection of fluconazole-resistant yeasts.

Topics: Agar; Antifungal Agents; Candida; Candida albicans; Candidiasis, Oral; Chromogenic Compounds; Culture Media; Drug Resistance, Microbial; Evaluation Studies as Topic; Fluconazole; Humans; Mycology; Sensitivity and Specificity; Yeasts

Five denture stomatitis patients demonstrating Candida albicans on both maxillary dentures and palates volunteered to test the effects of Peridex oral rinse in treating their oral disease. They used Peridex rinse both as a mouthrinse and as a denture soak for a period of 24 days. Agar replicas of the tissue-fitting surfaces of the maxillary dentures revealed elimination of C. albicans. Significant decreases in palatal inflammation were also noted, although some inflammation was still evident. Several weeks after the termination of Peridex oral rinses, inflammation increased as concentrations of C. albicans on the denture surface returned to pretreatment levels. A marked similarity in the site-specific localization of this yeast species on the denture was noted before and after Peridex rinse treatment.

Topics: Acrylic Resins; Agar; Candida albicans; Candidiasis, Oral; Chlorhexidine; Denture Bases; Denture Cleansers; Denture, Complete; Ecology; Humans; Microbiological Techniques; Mouthwashes; Palate; Recurrence; Stomatitis, Denture

Topics: Agar; Candida; Candidiasis, Oral; Humans; Mouth Mucosa; Saliva