Oral Candida Species Research Articles

Multi-drug resistant oral Candida species isolated from HIV-positive patients in South Africa and Cameroon

Candida species are a common cause of infection in immune-compromised HIV-positive individuals, who are usually treated with the antifungal drug, fluconazole, in public hospitals in Africa. However, information about the prevalence of drug resistance to fluconazole and other antifungal agents on Candida species is very limited. This study examined 128 Candida isolates from South Africa and 126 Cameroonian Candida isolates for determination of species prevalence and antifungal drug susceptibility. The isolates were characterized by growth on chromogenic and selective media and by their susceptibility to 9 antifungal drugs tested using the TREK™ YeastOne9 drug panel (Thermo Scientific, USA). Eighty-three percent (82.8%) of South African isolates were Candida albicans (106 isolates), 9.4% were Candida glabrata (12 isolates), and 7.8% were Candida dubliniensis (10 isolates). Of the Cameroonian isolates, 73.02% were C. albicans (92 isolates); 19.05% C. glabrata (24 isolates); 3.2% Candida tropicalis (4 isolates); 2.4% Candida krusei (3 isolates); 1.59% either Candida kefyr, Candida parapsilopsis, or Candida lusitaneae (2 isolates); and 0.79% C. dubliniensis (1 isolate). Widespread C. albicans resistance to azoles was detected phenotypically in both populations. Differences in drug resistance were seen within C. glabrata found in both populations. Echinocandin drugs were more effective on isolates obtained from the Cameroon than in South Africa. A multiple-drug resistant C. dubliniensis strain isolated from the South African samples was inhibited only by 5-flucytosine in vitro on the YO9 panel. Drug resistance among oral Candida species is common among African HIV patients in these 2 countries. Regional surveillance of Candida species drug susceptibility should be undertaken to ensure effective treatment for HIV-positive patients.

Clinical study on anti-fungal drug activity against clinically isolated strains of oral Candida species

ObjectivesThe present study was undertaken to evaluate the anti-fungal activity of amphotericin B (AMPH-B), flucytosine (5-FC), fluconazole (FLCZ), miconazole (MCZ), itraconazole (ITCZ), and micafungin (MCFG) against clinically isolated Candida strains from oral candidiasis (OC) patients and to collect information useful for the treatment of OC. Subjects and methodsThe study includes 116 strains of Candida isolated from patients. The Candida species were identified by polymerase chain reaction. The minimum inhibitory concentration (MIC) of each drug against each Candida species was determined. ResultsOf the 106 participants (30 males and 76 females), 57 had OC, including 42 cases of pseudomembranous OC, 11 cases of erythematous OC, 2 cases of hypertrophic OC, and 2 cases of mixed pseudomembranous/erythematous OC. The Candida species isolated were Candida albicans (93 strains), C. glabrata (19 strains), and C. tropicalis (4 strains). AMPH-B and 5-FC had low MIC values against all species of Candida and a low incidence of resistance development. In some species of Candida, FLCZ and ITCZ showed high MICs, but MCZ had a low MIC value. AMPH-B, MCZ, and ITCZ prescribed to OC patients were effective against OC with respect to alleviation of OC symptoms. ConclusionMIC values of anti-fungal drugs against Candida strains isolated from OC patients were obtained and the 3 anti-fungal drugs given to OC patients were found to be effective against OC in spite of differences in their MIC values and in the number of resistant strains (or strains with a high MIC value).

Asymptomatic oral yeast carriage and antifungal susceptibility profile of HIV-infected patients in Kunming, Yunnan Province of China

BackgroundOral Candida colonization and its relation with predisposing factors in HIV-infected patients have received wide concerns during recent decades. In this study, we investigated asymptomatic oral Candida carriage rate, species distribution and antifungal susceptibility of 604 HIV-infected patients and 851 healthy individuals in Kunming, Yunnan Province of China.MethodsMucosal swab sampling was taken from each subject and CHROMagar Candida agar medium and API 20C AUX system were used to identify yeast isolates. In vitro antifungal susceptibility was tested by the broth microdilution method according to the M27-A2 document of the Clinical and Laboratory Standard Institute (CLSI).ResultsThe oral yeast colonization rate in HIV-infected patients (49.5%) was higher than that of healthy subjects (20.7%). Candida albicans constituted the most frequent species, accounting for 82.2% of yeast isolates. The remaining species were composed of C. glabrata, C. parapsilosis, C. krusei, C. tropicalis, C. rugosa, C. norvegensis, Pichia ohmeri and Saccharomyces cerevisiae. In HIV-infected patients, asymptomatic oral yeast colonization was associated with low CD4 cell count (<200 cells/mm3) and lack of highly active antiretroviral therapy (HAART). Different Candida species isolated from our samples presented different susceptibility to voriconazole, fluconazole and itraconazole. Amphotericin B had the best inhibiting effect for all isolates.ConclusionOral yeast colonization in Han Chinese patients with HIV from Kunming had common and unique features and was associated with CD4 cell number and HARRT. Amphotericin B should be used with first priority in controlling Candida infection in Han Chinese patients from Kunming. Our results provide first hand information on monitoring oral yeasts colonization in HIV-infected patients from Kunming, China.

Langerhans cells and their role in oral mucosal diseases.

Dendritic cells are arguably the most potent antigen-presenting cells and may be the only cells capable of initiating the adaptive immune response. The epithelial residents of dendritic cells are Langerhans cells, which serve as the “sentinels” of the mucosa, altering the immune system not only to pathogen entry but also of tolerance to self antigen and commensal microbes. Oral mucosal Langerhans cells are capable of engaging and internalizing a wide variety of pathogens and have been found responsive to nickel in patients with nickel allergies, oral Candida species, oral lichen planus, lichenoid drug eruptions, graft versus host diseases, periodontal diseases median rhomboid glossitis, human immunodeficiency virus infection, hairy leukoplakia of the tongue, and oral squamous cell carcinoma. Review focuses on the role of antigen-presenting cells in particular Langerhans cells to better understand the mechanisms underlying immune responses. In this review, comprehensive detail about mucosal diseases has been compiled using the PubMed database and through textbooks.

The effect of psychoactive substances (drugs) on the presence and frequency of oral Candida species and Candida dubliniensis.

The Goal:The goal of this study was to determine the effect of psychoactive substances (drugs) on the presence and frequency of oral Candida species and Candida dubliniensis.Materials and methods:For the purpose of achieving the set goals, we chose a sample. Sixty bed-ridden patients from the Institute for Alcoholism and Other Addictions in Sarajevo Canton, both males and females between 18 and 60 years of age, were included in the research and assigned to two different groups (alcohol addicts and opiate addicts). After extensive anamnesis and a clinical examination, samples of oral epithelia were taken for microbiological identification. Two confirmatory methods were used for the identification of Candida species: the blastesis test and cultivation in a chromatophilic medium (Chrom agar). A yeast assimilation test (API test) was used for the identification of non-albicans Candida. A separate test was used to identify Candida dubliniensis (PAL agar).Results:The results of the microbiological analysis confirmed the frequency of Candida albicans (43%) in psychoactive substance addicts, as well as an increase in non-albicans Candida regardless of the type of addiction (34%). The presence of Candida dubliniensis was proven in psychoactive substance addicts (23%) and it was confirmed that the frequency of bacterial adherence of Candida dubliniensis is directly proportional to the duration of the drug-addiction.Conclusion:The abuse of psychoactive substances has an effect on the frequency of albicans and non-albicans species of oral Candida. Based on the findings, we have concluded that psychoactive substances (opiates and alcohol) lead to an increase in oral Candida dubliniensis regardless of the type of addictions.

Oral Candida species in head and neck cancer patients treated by radiotherapy

This paper aimed to identify and quantify Candida on head and neck irradiated patients with two comparative elderly populations. Saliva was sampled from 29 head and neck irradiated patients (group 1) 34 non-institutionalized elderly patients (group 2) and 29 institutionalized elders (group 3) and matched by age. For quantification, the obtained saliva was sewed on CHROMagar Candida(®), which was used also for presumptive identification of Candida, API 20C AUX(®), microculture and RAPD (OPE-18) were used for the final identification. Among the 92 patients surveyed, 51 (55.4%) had scores classified as positive for Candida, and among individuals of groups 1 and 3, 58.6% had Candida. There was higher positive/carrier conditions (CFU/sample) in groups 1 and 3, comparing with group 2 (P=0.011). Gender was not associated with Candida portability (P=0.334). Candida portability was significantly associated with the presence of candidosis (P=0.031) and xerostomic state (P=0.007). The isolates and definitive confirmed colonies were Candida albicans, Candida dubliniensis, Candida tropicalis, Candida krusei, Candida glabrata, Candida parapsilosis, Candida guilliermondii, Candida lusitaniae, and Candida kefyr. Among the species identified, C. albicans was the most frequent, followed by C. tropicalis, C. parapsilosis and C. glabrata. C. albicans was more prevalent in group 2 and 3, 45% and 41.2%, respectively, whereas, the most prevalent species in group 1 were C. tropicalis (27%), C. albicans and C. parapsilosis (16.2% for both). On multiple statistical models, only radiotherapic treatment was associated with positiveness to Candida. Diversification and major prevalence of non-albicans species were observed in irradiated patients on head and neck and this treatment is straightly associated with fungus positiveness.

Oral Candida carriage and species prevalence amongst habitual gutka‐chewers and non‐chewers

Oral Candida colonisation is higher in tobacco smokers as compared to non-smokers; however, it remains unknown whether smokeless tobacco chewers are susceptible to increased oral Candida colonisation. The aim was to determine the oral Candida carriage and species prevalence amongst habitual gutka-chewers and non-chewers in a cohort from Karachi, Pakistan. Forty-five gutka-chewers and 45 non-chewers were included. Information regarding age, sex, duration of gutka-chewing habit, daily frequency of gutka consumption, duration of holding gutka in the mouth, daily frequency of tooth-brushing and tongue brushing was collected using a questionnaire. Oral yeast samples were collected by scraping the dorsum of the tongue and bilateral buccal mucosa with a sterile cotton swab. Identification of yeast species was performed using standard techniques. Tongue lesions were identified and recorded. Unstimulated whole salivary flow rate (UWSFR) was also measured. There was no significant difference in the mean age, UWSFR and oral Candida carriage among gutka-chewers and non-chewers. Individuals were chewing gutka since 4·4 years and were consuming five gutka sachets daily. Candida albicans (C. albicans) was the most common yeast species isolated from 57·8% gutka-chewers and 64.4% non-chewers. In 24.4% gutka-chewers and 22·2% non-chewers, two candidal strains (C. albicans and Candida tropicalis) were isolated. In conclusion, the present results indicated no significant difference in oral Candida carriage in habitual gutka-chewers and non-chewers.

Amphotericin B-Induced in vitro Postantifungal Effect on Candida Species of Oral Origin

Objective: The aim of this investigation was to measure the postantifungal effect (PAFE) of 6 different oral Candida species following exposure to amphotericin B. Materials and Methods: Five oral isolates each of Candida albicans, Candida tropicalis, Candida krusei, Candida parapsilosis, Candida glabrata and Candida guilliermondii (total of 30 isolates) were examined for the presence of PAFE after 1 h of exposure to the minimum inhibitory concentration of amphotericin B. The PAFE was determined as the difference in time (hours) required for the growth of the drug-free control and the drug-exposed test cultures to increase to 0.05 absorbance level following removal of amphotericin B. Results: The mean duration of amphotericin B-induced PAFE was lowest for C. albicans (5.91 ± 0.31 h) and greatest for C. parapsilosis (12.72 ± 0.11 h), while C. guilliermondii (8.32 ± 0.33 h), C. glabrata (8.43± 0.21 h), C. krusei (9.68 ± 0.23 h) and C. tropicalis (10.98 ± 0.18 h) elicited intermediate values. Conclusion: Even a limited exposure to sublethal concentrations of amphotericin B suppressed growth of Candida species of oral origin. The significant variation in amphotericin B-induced PAFE amongst different Candida species may have clinical implications in terms of amphotericin B regimens used in the management of oral candidiasis.

Chemical composition, antioxidant and antifungal potential of Melaleuca alternifolia (tea tree) and Eucalyptus globulus essential oils against oralCandida species

Eucalyptus globulus and Melaleuca alternifolia essential oils has been of interest to researchers because they are traditionally used for the treatment of fungal infections and especially candidiasis. The chemical composition of hydrodistilled essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS), and their antifungal activity was tested against 32 Candida strains including 15 species. The antioxidant activities (DPPH, reducing power, and superoxide anion radical-scavenging activity) were also investigated. Tea tree essential oil was particularly rich on terpinen-4-ol (40.44%), gamma terpinene (19.54%) and 1,8-cineole (95.61%) and alpha-pinene (1.5%) for the E. globulus oil. E. globulus oil was more efficient and had the best antifungal effect on oral Candida albicans and Candida glabratastrains comparing to the results obtained with Amphotericin B. Even at low concentrations, these oils drastically impair the maximum yield and growth rate of both C. albicans and C. glabrata on YPD medium. The Tea Tree essential oil displayed the highest DPPH scavenging ability with the lowest IC50 value (IC50, 12.5 µg/ml), the greater reducing power and bleaching of β-carotene (EC50, 24 µgml-1 and IC50, 42 µgml-1, respectively) as compared to E. globulusoil and BHT. These findings support the interest of E. globulus and M. alternifolia essential oilsas an efficient oral hygiene tool (anti-Candida spp.) and as a source of antioxidant compounds. Key words: Candida, Melaleuca alternifolia, Eucalyptus globulus, gas chromatography-mass spectrometry, antioxidant, antifungal activities.

English

During the past two decades, there has been a significant increase in the prevalence of fungal infections caused by&nbsp;Candida&nbsp;species. Oral candidiasis is a common opportunistic infection of the oral cavity caused by&nbsp;yeast&nbsp;fungi of the genus&nbsp;Candida&nbsp;on the mucous membranes of the&nbsp;mouth. To isolate and determine the incidence rate of oral&nbsp;Candida&nbsp;species in periodentitis and gingivitis&nbsp;patients referred to school of dentistry, Ahvaz&nbsp;Jundishapur University of Medical Sciences, Ahvaz, Iran, this study was carried out in 172 patients with periodentitis and gingivitis aged 11 to 72 years. Swabs samples were taken from salivary secretion, the palate mucosa and dentine carious lesions and were cultured directly on Sabouraud dextrose agar medium. Isolated yeasts were identified by CHROMagarCandida, germ tube test and Clamidoconidia formation (corn meal agar plus Tween 80 medium).&nbsp;Results showed the prevalence of&nbsp;Candida albicans&nbsp;(n = 120, 75%),Candida&nbsp;glabrata&nbsp;(n = 20, 12.5%),&nbsp;Cadida tropicalis&nbsp;(n = 10, 6.5%),&nbsp;Candida dubliniensis&nbsp;(n = 6, 4.0%) and&nbsp;Cadida krusei&nbsp;(n = 3, 2.0%). In this investigation, germ tube-test and chlamydospore formation were positive in the isolates that produced dark-green colonies and were considered as&nbsp;C. dubliniensis&nbsp;and light-green colonies were identified as&nbsp;C. albicans.&nbsp;CHROMagar&nbsp;Candida&nbsp;is a satisfactory isolation medium for oral and dental specimens. It is a satisfactory method for correct and rapid identification of common yeast species and easy recognition of mixed cultures in clinical samples. &nbsp; Key words:&nbsp;Periodentitis, gingivitis, oral candidiasis, CHROMagar

Investigating biofilm production, coagulase and hemolytic activity in Candida species isolated from denture stomatitis patients.

Oral candidiasis, in the form of Candida-associated denture stomatitis, represents a common disease in a large percentage of denture wearers, and Candida albicans remains the most commonly isolated species. In this study, we aimed to evaluate biofilm production, coagulase and hemolytic activity of Candida species isolated from denture stomatitis patients. This study included 70 patients (31 female, 39 male). Forty-eight of the patients were found to have a positive culture. A total of 48 Candida isolates representing five species, C. albicans (n=17), C. glabrata (n=10), C. krusei (n=9), C. kefyr (n=7) and C. parapsilosis (n=5), were tested. Their coagulase activities were evaluated by a classical tube coagulase test with rabbit plasma. A blood plate assay on 3% enriched sheep blood Sabouraud-dextrose agar (SDA) was used to determine their in vitro hemolytic activities. Biofilm production was determined by a visual tube method. Twenty-one Candida isolates exhibited coagulase activity, and the coagulase activities of the C. albicans (64.7%) isolates were higher than other species. C. albicans, C. glabrata, C. kefyr and C. krusei species demonstrated beta hemolysis. C. parapsilosis strains failed to demonstrate any hemolytic activities. Fifteen (88.0%) of the C. albicans strains were biofilm positive. Six (35.2%) of these strains were strongly positive, 8 (47.0%) C. albicans strains were moderately positive and 1 (5.8%) C. albicans strain was weakly positive. Sixteen (51.6%) of the non-albicans Candida strains were biofilm positive while 15 (48.3%) did not produce biofilms. The results of this present study indicate coagulase, hemolytic activity and biofilm production by Candida spp. isolated from patients with denture stomatitis. Investigations of these virulence factors might be helpful in gaining information about the possible virulence of oral Candida species related to denture stomatitis.

Determination of the percentage inhibition of diameter growth (PIDG) of Piper betle crude aqueous extract against oral Candida species

Species within the genus Candida have been implicated in many fungal diseases such as candidiasis or thrush. The increasing clinical and microbiological resistance of Candidaspecies towards several commonly prescribed antifungal agents however, has lead to the search for new active antifungal compounds from natural resources. This study was carried out to screen the susceptibility of the aqueous extract of Piper betle towards seven species of oral Candida. It was found that P. betle extract exhibited high antifungal activities towards Candida albicans, Candida tropicalis, Candida glabrata, Candida dubliniensis, Candida lusitaniae, Candida krusei and Candida parapsilosis. The minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) value of P. betle extract towards all Candida species was found to be similar (12 mg/ml) except towards C. albicanswhich has been shown to have MIC value of 12 mg/ml and slightly higher MFC value of 25 mg/ml. The recorded data on the growth responses of the species to various concentrations of the extract following a 24 h incubation period were analysed, using the percentage inhibition of diameter growth (PIDG) against chlorhexidine gluconate (CHX). The determination of PIDG values for C. albicans, C. tropicalis, C. lusitaniae, C. dubliniensis andC. glabrata has shown that the aqueous extract of P. betle outstrips the positive control used, that was 0.12% w/v chlorhexidine with PIDG values of more than 50% at P. betleconcentration of 25 mg/ml. In contrast, PIDG for C. krusei and C. parapsilosis shows that at 25 mg/ml concentration of P. betle extract has little influence on growth inhibition compared to CHX. Thus, the results obtained have shown the potential use of P. betle extract as antifungal agent and thus significantly contribute to its antifungal development. Key words: Candida sp., oral Candida, Piper betle, antifungal activity, percentage inhibition of diameter growth (PIDG).

Oral Candidal Colonization in Cleft Patients as a Function of Age, Gender, Surgery, Type of Cleft, and Oral Health

To assess the colonization rate of oral Candida species and the influence of age, gender, oral health status, number of surgeries, and type of cleft. A prospective study of 60 patients with cleft and 60 control subjects was carried out at the Cleft Centre at King Abdullah University Hospital and the Maxillofacial Unit at Jordan University of Science and Technology between October 2007 and June 2008. Oral health was assessed using the Gingival, Plaque, and Decayed, Missing, and Filled (DMFT/dmft) indexes using World Health Organization criteria. A culture swab was obtained from the tongue and buccal and palatal mucosae. Candida albicans and other Candida species were identified using the germ tube test and the automated biochemical test panel VITEK. The colonization rate of Candida in patients with cleft (63.3%) was significantly higher than in healthy control subjects (18.3%). The colonization rate of Candida and the distribution of C albicans varied with age but were not significantly associated with gender in patients with cleft and healthy controls. The candidal colonization rate was highest in patients with cleft who had at least 3 surgeries (78.2%) and in patients with bilateral clefts (77.7%). Patients with cleft had a significantly poorer health status than healthy controls; however, this was not influenced by the type of the cleft or the number of surgeries. Patients with cleft had a significantly higher rate of oral candidal colonization compared with control subjects, which varied with age, type of cleft, and the number of surgical interventions. Oral health status was significantly poorer in patients with cleft.

Atividade antifúngica do extrato aquoso de Arctium minus (Hill) Bernh. (Asteraceae) sobre espécies orais de Candida

Este estudo teve como objetivo avaliar a atividade antifúngica do extrato aquoso de folhas de "bardana" [Arctium minus (Hill) Bernh.], por meio da determinação da Concentração Inibitória Mínima (CIM) e Concentração Fungicida Mínima (CFM) sobre diferentes espécies e linhagens do gênero Candida. Foram incluídas no trabalho as espécies de Candida albicans, C. tropicalis, C. glabrata, C. stellatoidea, C. dubliniensis e C. krusei. Utilizaram-se quatro linhagens de C. albicans e três de C.tropicalis, enquanto que para as demais espécies, apenas uma linhagem foi testada. Estas leveduras foram utilizadas no estudo devido à importância e frequência na cavidade bucal. As leveduras foram submetidas a tratamentos com concentrações do extrato aquoso que variaram de 0,09 a 25 mg mL-1. Os resultados indicaram que concentrações inferiores a 12,5 mg mL-1 não são suficientes para apresentar efeito fungistático ou fungicida. A concentração de 12,5 mg mL-1 apresentou efeito fungistático sobre a maioria das linhagens e espécies testadas (C. albicans 04A e ATCC44858; C. tropicalis 23600 e 23651; C. glabrata; C. stellatoideia; C. dubliniensis e C. krusei). Entretanto, efeito fungicida foi observado apenas sobre a espécie C. krusei (CFM=12,5 mg mL-1). Comportamento diferenciado foi observado entre diferentes linhagens de uma espécie (para C. albicans e C. tropicalis). Assim, a ação antifúngica do extrato aquoso de A. minus (Hill) Bernh. provavelmente está associada à variabilidade genética existente entre as diferentes linhagens de uma mesma espécie e das diferentes espécies, sendo que concentrações inferiores a 12,5 mg mL-1 não apresentaram efeito sobre as leveduras testadas. Com base na metodologia empregada e dentro das limitações deste estudo, conclui-se que o extrato aquoso de A. minus revelou efeito antifúngico, principalmente fungistático, contra espécies de Candida orais. Porém, novos estudos são necessários para avaliar o seu real potencial antifúngico dentro do meio bucal.

Associations among the use of highly active antiretroviral therapy, oral candidiasis, oral Candida species and salivary immunoglobulin A in HIV-infected children

The aim was to examine the impact of antiretroviral therapy on the prevalence of oral candidiasis, recovery of oral Candida spp. , and salivary levels of total secretory immunoglobulin A (SIgA) and Candida-specific SIgA in human immunodeficiency virus (HIV)-infected children. Sixty-six HIV+ and 40 HIV- children were cross-sectionally examined for the presence of oral lesions. Whole stimulated saliva samples were collected for the identification of Candida spp. using culture and measurement of total and specific SIgA using enzyme-linked immunosorbent assay (ELISA). The HIV+ children had a higher prevalence of oral candidiasis (P < .05), higher frequency of detection of Candida spp. (P < .05), and higher levels of total (P < .05) and Candida-specific SIgA (P < .001) than the HIV- children. Among the HIV+ subjects, antiretroviral users had lower viral loads (P < .001) and lower levels of Candida spp. (P < .05) and total SIgA (P < .05) compared with antiretroviral nonusers. The use of antiretroviral therapy was associated with decreases in the prevalence of oral candidiasis. This diminished exposure to Candida spp. was accompanied by decreases in levels of total and Candida-specific SIgA.

Oral Candida infection and colonization in solid organ transplant recipients

Oral Candida carriage and infection have been reported to be associated with a greater risk for systemic infection in transplant recipients; however, a systematic analysis of the oral Candida titers and species has not been previously conducted. The objectives of this study were to determine the prevalence of oropharyngeal candidiasis, the oral carrier status, Candida titers and species in this population. Ninety kidney and heart transplant subjects and 72 age-matched healthy controls were included. Swabs from the oral mucosa and a standardized amount of unstimulated saliva were plated on Chromagar Candida, and colony-forming units per millilitre were calculated. Initial speciation was based on colony color and was confirmed by standard germ tube, biotyping, or polymerase chain reaction assays. Infection with C. albicans was detected in seven transplant subjects and none of the controls. The transplant group had significantly higher oral Candida titers than the control group. There were no statistically significant relationships between the dose or type of immunosuppressants and oral Candida titers or infection. A significantly higher percentage of transplant subjects were colonized by more than one species, compared with control subjects. The most frequent species combination in transplant subjects was C. albicans and C. glabrata. C. glabrata was isolated from 13.5% of transplant carriers and none of the controls. Increased oral Candida infection and carriage titers were found in the transplant population. Although the majority of transplant patients were colonized by C. albicans, C. glabrata appears to emerge as the second most prevalent species.

Antimicrobial activity and local release characteristics of chlorhexidine diacetate loaded within the dental copolymer matrix, ethylene vinyl acetate

In vitro results are presented for a novel oral drug-delivery system ultimately intended for treatment of oral infections in immunocompromised patients. Test samples of ethylene vinyl acetate copolymer (EVA) containing chlorhexidine diacetate (CDA) showed desirable antimicrobial properties and steady, slow release into aqueous and other media after an initial burst of drug release in the first day of liquid exposure. By washing away this initial burst, the proposed mouthguard device should be capable of sustained delivery of locally effective CDA concentrations far below systemically toxic levels. A prolonged room temperature shelf-life of at least 1 year, and effectivity against a wide range of oral bacteria and Candida species was demonstrated. Drug loaded films showed a top-to-bottom asymmetry in drug release, but good lateral homogeneity, and a linear relationship between initial CDA loading concentration (from 0.63 to 10 wt %) and days 3-14 release rates in a static aqueous environment. The EVA matrix containing CDA appears to possess many suitable properties for localized oral delivery of sustained antimicrobial activity.

Oral Candida species in healthy and HIV-infected subjects in Chennai, South India.

Objective: Candidiasis is the most common fungal infection in human immunodeficiency virus (HIV) - infected individuals. As there is sparse data on the oral Candida species in HIV- infected individuals in India, we characterized Candida species from the oral cavity in two cohorts - with and without HIV infection and with presence or absence of clinical oral candidiasis, in Chennai, South India.Methods: Saliva samples were collected from 147 consecutive study participants by the oral rinse technique. Candidal species were isolated by culturing specimens on Sabouraud‘s dextrose agar. The pure cultures so derived were speciated using the commercially available ID32C system, and the results were interpreted using APILAB plus software.Results: In the HIV seropositive group, the most commonly isolated candida species was C.albicans (86%) followed by C.tropicalis (23%), C.guilliermondi (6%), C.krusei (5%) and others (4%). In the healthy cohort without clinical candidiasis, C.tropicalis was the most commonly isolated species.Conclusion: There appears to be a marked variation in oral Candida species found in HIV-seropositive and seronegative individuals in India. To our knowledge, this is the first attempt to identify oral Candida species in a South Indian population.

Poster 019: Clinical Study on the Detection of Oral Candida Species by Microscopy

Poster 019: Clinical Study on the Detection of Oral Candida Species by Microscopy

Clinical Application of a Rapid and Simple Supersensitive Identification Method for the Identification of Oral Candida Species From Oral Rinse Specimens

The ratio of old and the immune-compromised patients has recently increased in Japan due to the graying of modern society. As a result, a large number of patients who visit the oral medicine and dental clinic who demonstrate the presence of oral candidiasis. However, it is not easy to diagnose oral candidiasis by an inspection alone because pseudo membranous candidiasis has recently decreased, while erythematous candidiasis has increased. Conventional culture method takes a few days to obtain the results and we therefore lose the chance to treat superficial candidiasis before deep-seated candidosis has a chance to develop.