Candidal carriage in the oral cavity of human immunodeficiency virus-infected subjects

Quantification of Oral Candidal Carriage Rate and Prevalence of Oral Candidal Species in HIV Patients with and Without Highly Active Antiretroviral Therapy

BACKGROUND

Most documents review decrease in the prevalence of HIV related oral lesions to the tune of 10-50% following the advent of HAART. However long term use of HAART on oral health status of HIV infected subjects is poorly documented. Also antifungal agents can effectively treat mucosal candidiasis. However their use can lead to colonization with less susceptible strains among normal susceptible strains.

AIMS AND OBJECTIVES

To know the candidal carriage rate (i.e. presence/absence of candidal growth), candidal density(CFUs/ml) & species variations (species diversity) in HIV positive individuals with and without highly active anti-retroviral therapy (HAART), attending the regional voluntary Counselling and Confidential Testing Centre (VCCTC).

MATERIALS AND METHODS

The study population were categorized into 3 groups. Method followed were Germ tube test, Chlamydospore formation test, CHROM-Agar test.

RESULTS

Quantification comparison study of candidal carriage rate, density with detection of various candidal species in the oral cavity of HIV-positive individuals with and without HAART therapy was conducted.

CONCLUSION

HIV positive individuals with HAART therapy treatment prooved higher candidal carriage rate and lower density than Non-HAART category.

Biofilm-Producing Candida Species Causing Oropharyngeal Candidiasis in HIV Patients Attending Sukraraj Tropical and Infectious Diseases Hospital in Kathmandu, Nepal

Introduction

Oropharyngeal candidiasis are the commonest fungal infections among HIV-positive patients. The main objective of this study was to explore biofilm-producing Candida species causing oropharyngeal infections among HIV patients attending Sukraraj Tropical and Infectious Diseases Hospital (STIDH) in Kathmandu, Nepal.

Methods

Oropharyngeal swabs were collected from the HIV-positive patients between July and December 2019. A total of 174 oropharyngeal swabs were cultured on Sabouraud Dextrose Agar (SDA). All samples were inoculated on SDA slants supplemented with chloramphenicol and underwent incubation at 37°C for 24-48 hours. Any visible growth reported was processed for the identification of the species. Candida species were differentiated based on the growth and colour of the isolates on CHROM agar candida. Biofilm production in Candida species was determined by the microtiter plate method (MPM). Antifungal susceptibility testing was performed using the disc diffusion method.

Results

Among 174 oropharyngeal samples, 23.6% (n=41/174) of them had oropharyngeal infections and 36.6% of the oropharyngeal infections (15/41) had CD4 T-lymphocytes count below 200 cells/mm³ who were also active tobacco users (p<0.05). Among Candidial growth, 61% (25/41) were Candida albicans and 39% (16/41) were non-albicans. Of 41 Candida spp., 65% (27/41) were biofilm producers. An equal proportion of Candida albicans (4 isolates) and non-albicans (4 isolates) were strong biofilm producers. C. albicans isolates were sensitive towards clotrimazole (96%; 24/25) and fluconazole (92%; 23/25), whereas sensitivity towards ketoconazole was only 48% (12/25). Non-albicans Candida was highly sensitive to amphotericin-B (62.5%; 10/16) followed by clotrimazole (56.2%; 9/16). The biofilm-producing Candida isolates showed the highest resistivity (51.9%; 14/27) to ketoconazole and lowest (22.2%; 6/27) to clotrimazole.

Conclusion

Oropharyngeal candidiasis is a common opportunistic infection among HIV-infected individuals. The majority of cases of oropharyngeal candidiasis are caused by biofilm producers Candida albicans and non-albicans Candida. Biofilm producers Candida were more resistant towards commonly used antifungal drugs.

Oral colonization by Candida species and associated factors in HIV-infected patients in Ahvaz, southwest Iran

OBJECTIVES

Oropharyngeal candidiasis is one of the most common opportunistic fungal infections among human immunodeficiency virus (HIV)-infected individuals. The most common cause is Candida albicans, followed by non-albicans Candida. This study aimed to identify colonized Candida species in HIV-infected patients from Ahvaz, Iran. Additionally, the relationships between immunity-related factors, lifestyle, and colonization of Candida spp. were studied.

METHODS

Oral swabs were taken from 201 HIV-positive patients referred for consultations at the Behavioral Modification Center. Oral Candida colonization was detected using culture-based and molecular assays. Data were assessed by descriptive statistics and analyzed to investigate the correlation between Candida colonization and various factors, including the CD4+ cell count and viral load.

RESULTS

It was found that 43.8% of patients were positive for Candida. The most common species was C. albicans (48.0%), followed by non-albicans Candida isolates, including C. dubliniensis, C. glabrata, C. tropicalis, C. parapsilosis, C. guilliermondii, C. kefyr, and C. krusei. Colonization of Candida spp. in patients was associated with a CD4 count ≤200 cells/mm3 (odds ratio [OR], 4.62; p<0.05), history of shared injections (OR, 6.96; p<0.001), and sex (OR, 3.59; p<0.05).

CONCLUSIONS

The results of this study showed that C. albicans was the dominant pathogen. The risk factors for colonization of Candida spp. were a CD4 count ≤ 200/mm3 , a history of shared injections, and sex. Other factors with potential relationships include viral load, age, and opportunistic infections, but further investigations are needed.

Oral candidal carriage correlates with CD4+ cell count but not with HIV and highly active antiretroviral therapy status

AIM

The occurrence of oropharyngeal candidiasis (OPC) may be influenced by oral candidal carriage (OCC). Although OPC is strongly associated with low CD4⁺ cell count (400-700 cells/mm³ ) and a lack of highly active antiretroviral therapy (HAART), the effect of these two parameters on OCC is debatable. We investigated the oral candidal carriage, species diversity, antifungal susceptibility and the association of OCC with CD4⁺ cell count and HAART.

METHODS

Oral candidal isolates from 120 HIV⁺ patients (60 receiving and 60 not receiving HAART) and 60 healthy controls were quantified, and their species determined using standard culture and biochemical methods, followed by antifungal susceptibility testing using the agar dilution method.

RESULTS

The OCC was significantly higher in HIV⁺ patients; Candida albicans was the most frequently isolated species in both groups, followed by Candida tropicalis. Candidal density carriage correlated significantly with CD4⁺ cell count, but not with HIV and HAART status. Among the isolates from HIV⁺ patients, 35.4% showed reduced susceptibility to fluconazole.

CONCLUSION

HIV status results in significantly elevated rates of OCC C albicans remains the predominant pathogen, although other species are emerging rapidly. Resistance to fluconazole is on the rise, and more efficient treatment strategies need to be implemented.

Candida spp. Determination and Th1/Th2 Mixed Cytokine Profile in Oral Samples From HIV+ Patients With Chronic Periodontitis

Background: Chronic periodontitis (CP), caused by bacteria and fungi, appears in up to 66% of HIV-patients. The impact and association of HIV-treatment (HAART) and Candida itself has not been properly evaluated in the development and progression of CP. The immunopathogenesis is characterized by CD4⁺ T-cells activation and the balance between the T-helper 1 (Th1) and T-helper 2 (Th2) or a mixed cytokine profile. Currently, the associated causes of an immune response in HIV-patients with CP is controversial. Our aims were the determination of Candida spp. and cytokine profile in oral samples from HIV-positive patients with CP, considering the CD4⁺ T cells levels and HAART use.

Methods: From 500 HIV-positive patients evaluated, 228 patients were enrolled. Patients were separated in groups: (A) n = 53 (≤200 CD4⁺ T-cells on HAART); (B) n = 57 (≤200 CD4⁺ T-cells without HAART); (C) n = 50 (>200 CD4⁺ T-cells without HAART); (D) n = 68 (>200 CD4⁺ T-cells on HAART). Candida spp. were isolated from the oral biofilm and crevicular fluid in CHROMagar and confirmed by endpoint PCR. Cytokine levels were measured by beads-based immunoassay in saliva by flow cytometry.

Results: 147 patients (64.5%) were positive to Candida spp. and 204 strains were isolated; 138 (67.6%) were C. albicans and the remaining C. non-albicans species (C. glabrata>C. tropicalis>C. krusei>C. dubliniensis). In this study, CHROMagar showed good sensitivity (95%) but poor specificity (68%); since of the 152 samples identified as C. albicans, only 131 were confirmed by PCR; from the 10 samples identified as C. glabrata, only six were confirmed. Finally, of the 42 samples detected as C. tropicalis, only five were confirmed. When evaluating Candida spp. presence, group A and D had higher isolation, while group B had the highest species diversity. Whereas, group C had a significant reduction of Candida spp. Despite the presence of Candida and HAART, we found a Th1/Th2 hybrid profile in the saliva of patients with low CD4⁺ T-cell count (group A).

Conclusion: Abundance and diversity of the Candida spp. detected in HIV-patients with CP could be related to HAART and low CD4⁺ T-cells levels. Also, the immunosuppression might promote a local Th1/Th2 hybrid cytokine profile.

Salivary human beta-defensins affected by oral Candida status in Chinese HIV/AIDS patients undergoing ART

OBJECTIVES

To observe relationships between oral Candida status and salivary human beta-defensin 2 and 3 (hBD-2 and hBD-3) levels in HIV/AIDS patients of Guangxi, China during the first year of antiretroviral therapy (ART) dynamically, and to understand the influence of ART on oral Candida status and salivary hBDs expressions.

METHODS

A prospective self-controlled study was carried to observe the dynamic changes of CD4⁺ T cell counts, oral Candida carriages and salivary hBD-2,3 expressions in HIV/AIDS patients during the first year of ART. A total of 90 HIV/AIDS patients were enrolled and were examined at the baseline, 3rd, 6th, 12th month of ART. Thirty healthy individuals were enrolled as control. Peripheral blood, oral rinse sample, and unstimulated whole saliva were collected to test CD4⁺ T cell counts, oral Candida carriages, and hBD-2,3 expressions.

RESULTS

In the first year of ART, CD4⁺ T cell counts increased significantly. However, oral Candida carriages and oral candidiasis decreased significantly, and salivary hBD-2 expressions in HIV/AIDS patients decreased gradually, salivary hBD-3 levels were highly variable. Salivary hBD-2 concentrations were positively related to oral Candida carriages.

CONCLUSIONS

The incidence of oral candidiasis among HIV/AIDS patients gradually decreased due to the immune reconstruction of ART. Salivary defensins might play an important role in Candida-host interaction in HIV/AIDS patients.

Forgotten fungi-the gut mycobiome in human health and disease

The human body is home to a complex and diverse microbial ecosystem that plays a central role in host health. This includes a diversity of fungal species that is collectively referred to as our 'mycobiome'. Although research into the mycobiome is still in its infancy, its potential role in human disease is increasingly recognised. Here we review the existing literature available on the human mycobiota with an emphasis on the gut mycobiome, including how fungi interact with the human host and other microbes. In doing so, we provide a comprehensive critique of the methodologies available to research the human mycobiota as well as highlighting the latest research findings from mycological surveys of different groups of interest including infants, obese and inflammatory bowel disease cohorts. This in turn provides new insights and directions for future studies in this burgeoning research area.

Candida species diversity and antifungal susceptibility patterns in oral samples of HIV/AIDS patients in Baja California, Mexico

Candidiasis is the most common opportunistic fungal infection in HIV patients. The aims of this study were to identify the prevalence of carriers of Candida, Candida species diversity, and in vitro susceptibility to antifungal drugs. In 297 HIV/AIDS patients in Baja California, Mexico, Candida strains were identified by molecular methods (PCR-RFLP) from isolates of oral rinses of patients in Tijuana, Mexicali, and Ensenada. 56.3% of patients were colonized or infected with Candida. In Tijuana, there was a significantly higher percentage of carriers (75.5%). Out of the 181 strains that were isolated, 71.8% were Candida albicans and 28.2% were non-albicans species. The most common non-albicans species was Candida tropicalis (12.2%), followed by Candida glabrata (8.3%), Candida parapsilosis (2.2%), Candida krusei (1.7%), and Candida guilliermondii (1.1%). Candida dubliniensis was not isolated. Two associated species were found in 11 patients. In Mexicali and Ensenada, there was a lower proportion of Candida carriers compared to other regions in Mexico and worldwide, however, in Tijuana, a border town with many peculiarities, a higher carrier rate was found. In this population, only a high viral load was associated with oral Candida carriers. Other factors such as gender, use of antiretroviral therapy, CD4+ T-lymphocyte levels, time since diagnosis, and alcohol/ tobacco consumption, were not associated with Candida carriers.

Oral candidiasis among African human immunodeficiency virus-infected individuals: 10 years of systematic review and meta-analysis from sub-Saharan Africa

Oral candidiasis (OC) is the most common opportunistic fungal infection among immunocompromised individuals. This systematic review and meta-analysis reports on the contribution of non-albicans Candida species in causing OC among human immunodeficiency virus (HIV)-infected individuals in sub-Saharan Africa between 2005 and 2015. Thirteen original research articles on oral Candida infection/colonization among HIV-infected African populations were reviewed. The prevalence of OC ranged from 7.6% to 75.3%. Pseudomembranous candidiasis was found to range from 12.1% to 66.7%. The prevalence of non-albicans Candida species causing OC was 33.5% [95% confidence interval (CI) 30.9–36.39%]. Of 458 non-albicans Candida species detected, C. glabrata (23.8%; 109/458) was the most common, followed by C. tropicalis (22%; 101/458) and C. krusei (10.7%; 49/458). The overall fluconazole resistance was 39.3% (95% CI 34.4–44.1%). Candida albicans was significantly more resistant than non-albicans Candida species to fluconazole (44.7% vs 21.9%; p < 0.001). One-quarter of the cases of OC among HIV-infected individuals in sub-Saharan Africa were due to non-albicans Candida species. Candida albicans isolates were more resistant than the non-albicans Candida species to fluconazole and voriconazole. Strengthening the capacity for fungal diagnosis and antifungal susceptibility testing in sub-Saharan Africa is mandatory in order to track the azole resistance trend.

Immunological and epidemiological factors affecting candidiasis in HIV patients beginning antiretroviral therapy in an Asian clinic

OBJECTIVES

Oropharyngeal candidiasis (OPC) is common in HIV patients beginning antiretroviral therapy (ART). Here we address the response to ART, and the roles of poor oral hygiene and defects in local innate immunity with a focus on salivary β-defensins, as they are implicated in control of candidiasis but have not been investigated in this context.

DESIGN

ART naïve HIV-infected adults (n=82) with <200 CD4⁺ T-cells/mm³ attending clinics at Cipto Mangunkusumo Hospital, Jakarta, were examined at the commencement of ART, and 73 were re-examined after 3 months. OPC was detected by clinical examination, and Candida albicans and fungal burdens were determined following culture on CHROMagar and saboroud-dextrose agar (resp). Salivary β-defensins (-2 and -3) were quantified by ELISA. Healthy control subjects (n=40) matched the patients by age and gender.

RESULTS

OPC was evident in 47 patients before ART, and associated with greater fingal burdens. No OPC was detected in healthy controls and culture positivity was rare. ART decreased the prevalence of OPC to 8/73 HIV patients re-examined after 3 months, with reduced total fungal and C. albicans burdens. The incidence of OPC was independent of oral hygiene. Hyposalivation was more common in untreated HIV patients (16%) than after 3 months on ART and was rare in healthy controls. HIV patients were also more likely to have acidic saliva. Salivary β-defensin-2 was elevated in the presence of C. albicans pseudohyphae and OPC after 3 months on ART, but β-defensin-3 was not affected by OPC or ART.

CONCLUSIONS

ART reduces the prevalence of OPC, and the total fungal and C. albicans burden. Levels of salivary β-defensin-2 may associate with OPC in HIV patients responding to ART.

Oral Candida spp carriage and periodontal diseases in HIV-infected patients in Ribeirão Preto, Brazil

The majority of HIV-infected patients develop Candida spp-associated clinical oral lesions. Studies have shown that asymptomatic oral colonization of Candida spp may lead to oral lesions or become a source of disseminated infections. The aim of this study was to verify the effects of periodontal conditions on Candida spp prevalence and Candida spp carriage in the oral cavity of HIV-infected patients compared to non-infected patients. Twenty-five patients not infected with HIV and 48 HIV-infected patients were classified according to periodontal conditions as being periodontal healthy or with periodontal disease. Candida spp carriage and classification were performed in oral rinse samples. Viral load and CD4+ T lymphocyte (CD4+L) counts were performed in blood samples from HIV-infected patients. No differences in Candida spp prevalence related to HIV status or periodontal condition were detected. However, Candida spp carriage was increased in periodontally affected HIV-infected patients when compared to periodontally healthy HIV-infected patients (p= 0.04). Periodontally healthy HIV-infected patients presented Candida spp carriage in similar levels as healthy or periodontally affected non-HIV-infected patients. Candida spp carriage was correlated with CD4+L counting in HIV-infected patients. We concluded that periodontal disease is associated with increased Candida spp carriage in HIV-infected patients and may be a predisposing factor to clinical manifestations of candidiasis.

Antifungal Drug Susceptibility of Candida Species Isolated from HIV-Positive Patients Recruited at a Public Hospital in São Luís, Maranhão, Brazil

Oropharyngeal candidiasis is the most common fungal infection in hospitalized patients with acquired immune deficiency syndrome (AIDS). Its progression results in invasive infections, which are a significant cause of morbidity and mortality. This study aimed to quickly and accurately identify Candida spp. from oral mucosa of AIDS patients recruited at Presidente Vargas Hospital, in São Luís city, Brazil and to evaluate the sensitivity profile of these fungi to antifungals by using an automated system. Isolates were collected from oropharyngeal mucosa of 52 hospitalized AIDS patients, under anti-viral and antifungal therapies. Patients were included in research if they were HIV-positive, above 18 years of age and after obtaining their written consent. CHROMagar^®Candida and the automated ViteK-2^®system were used to isolate and identify Candida spp., respectively. Antifungal susceptibility testing was performed using the ViteK-2^®system, complemented with the Etest^®, using the drugs amphotericin B, fluconazole, flucytosine, and voriconazole. Oropharyngeal candidiasis had a high prevalence in these hospitalized AIDS patients (83%), and the most prevalent species was Candida albicans (56%). Antifungal susceptibility test showed that 64.7% of the Candida spp. were susceptible, 11.8% were dose-dependent sensitive, and 23.5% were resistant. All the Candida krusei and Candida famata isolates and two of Candida glabrata were resistant to fluconazole. Most of AIDS patients presented oropharyngeal candidiasis and C. albicans was the most frequently isolated species. The results showed high variability in resistance among isolated species and indicates the need to identify the Candida spp. involved in the infection and the need to test antifungal susceptibility as a guide in drug therapy in patients hospitalized with AIDS. This is the first relate about AIDS patients monitoring in a public hospital in São Luís concerning the precise identification and establishing of antifungal profile of Candida spp..

Alcohol and tobacco consumption affect the oral carriage of Candida albicans and mutans streptococci

This study sought to determine if there is a relationship between the consumption of alcohol and tobacco and oral colonization by mutans streptococci and Candida species. Subjects were recruited from the University Dental Clinic of CEU Cardenal Herrera University (Moncada, Valencia). Information on alcohol and tobacco consumption was obtained by questionnaire. Individual stimulated saliva samples from 105 patients were obtained and selective media was used to isolate and quantify mutans streptococci and Candida spp. colony forming units per millilitre of saliva (CFU ml(-1) ). Samples were stratified by duration and quantity of alcohol and tobacco consumption. Alcohol consumption statistically significantly decreased oral carriage of mutans streptococci, whereas there was no effect on Candida albicans colonization levels. Tobacco users were found to harbour elevated levels of C. albicans; however, there was no observed effect on bacterial colonization by mutans streptococci. The carriage of other species investigated, such as Candida krusei, Candida tropicalis and lactobacilli, do not show a response to the consumption of the stimulants analysed. Microbial colonization of the oral cavity changes in a species-specific manner in response to dietary and social habits such as drinking alcohol and smoking.

SIGNIFICANCE AND IMPACT OF THE STUDY

In this paper, we evaluate the effect of alcohol and tobacco consumption on key species of the oral microflora. Our results show species-specific changes in two major opportunistic pathogens, such as Candida albicans and mutans streptococci, whereas other members of oral microflora are not affected by the consumption of the stimulants studied. We believe this original paper will contribute to raise awareness among the dental community towards a more personalized oral health assessment, taking in consideration alcohol and tobacco consumption in the prevention of specific oral and systemic pathologies.

Pyrostegia venusta (Ker Gawl.) Miers Crude Extract and Fractions: Prevention of Dental Biofilm Formation and Immunomodulatory Capacity

Background:

Caries and periodontal diseases remain as important diseases in the Brazilian population. One important pathogen associated with this situation is Streptococcus mutans and other important factor is this pathogen's ability to adhere firmly to the tooth surface leading to dental biofilm formation and caries development.

Objectives:

Determine the antibacterial and other biological activities of P. venusta related to its potential to be used in the treatment of caries and periodontal disease.

Methods:

The growth inhibition by P. venusta of Streptococcus mutans, S. mitis, S. oralis and Candida albicans was determined using the broth microdilution method. In addition, the effect of the samples in adherence and reducing production of acids by S. mutans, and germ-tube formation of C. albicans was analysed. The Nitric Oxide (NO) production and cytotoxicity of P. venusta to peripheral blood mononuclear cells (PBMC) and RAW 264.7 Cell Line Murine Macrophage from Blood were assessed.

Results:

The crude extract (CE) and ethyl-acetate (AF) and n-butanol (BF) fractions showed antibacterial activity. The ethyl-acetate (AF) fraction showed the highest inhibition percentage against the adherence of S. mutans and C. albicans cells without budding, beyond NO production inhibition. There was not any cytotoxicity in the murine macrophages RAW 264.7 cells.

Conclusion:

Our results suggest that P. venusta presents potential to be used as a preliminary source of compounds that can provide helpful activity when used in prophylaxis or treatment of caries or periodontal disease.

SUMMARY

Biological activities of Pyrostegia venusta and its potential for use in formulations for the prevention of oral diseases.

Abbreviations used: NO: Nitric oxide, PBMC: Peripheral blood mononuclear cells, CE: Crude extract, AF: Ethyl-acetate fraction, BF: n-butanol fraction, HF: Hexane fraction, WF: Water fraction, MIC: Minimum inhibitory concentration, MBC: Minimum bactericidal concentration, ATCC: American Type Culture Collection, CFU: Colony-forming units, BHI: Brain heart infusion, RPMI: Roswell Park Memorial Institute, MOPS: 3-(N-morpholino)propanesulfonic acid, DMEM: Dulbecco's modified Eagle's médium, LPS: Lipopolysacharide, MTT: 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide, OD: Optical density, AC: Acteoside,

RELATED FACTORS FOR COLONIZATION BY Candida SPECIES IN THE ORAL CAVITY OF HIV-INFECTED INDIVIDUALS

The colonization of the oral cavity is a prerequisite to the development of oropharyngeal candidiasis.

AIMS

The aims of this study were: to evaluate colonization and quantify Candida spp. in the oral cavity; to determine the predisposing factors for colonization; and to correlate the levels of CD4+ cells and viral load with the yeast count of colony forming units per milliliter (CFU/mL) in HIV-positive individuals treated at a University Hospital. Saliva samples were collected from 147 HIV patients and were plated on Sabouraud Dextrose Agar (SDA) and chromogenic agar, and incubated at 30 ºC for 72 h. Colonies with similar morphology in both media were counted and the result expressed in CFU/mL.

RESULTS

Of the 147 HIV patients, 89 had positive cultures for Candida spp., with a total of 111 isolates, of which C. albicans was the most frequent species (67.6%), and the mean of colonies counted was 8.8 × 10³ CFU/mL. The main predisposing factors for oral colonization by Candida spp. were the use of antibiotics and oral prostheses. The use of reverse transcriptase inhibitors appears to have a greater protective effect for colonization. A low CD4+ T lymphocyte count is associated with a higher density of yeast in the saliva of HIV patients.

Evaluation of gene expression SAP5, LIP9, and PLB2 of Candida albicans biofilms after photodynamic inactivation

With the increasing number of strains of Candida ssp. resistant to antifungal agents, the accomplishment of researches that evaluate the effects of new therapeutic methods, like photodynamic inactivation (PDI), becomes important and necessary. Thus, the objective of this study was to verify the effects of the PDI on Candida albicans biofilms, evaluating their effects on the expression of the gene hydrolytic enzymes aspartyl proteinase (SAP5), lipase (LIP9), and phospholipase (PLB2). Clinical strains of C. albicans (n = 9) isolated from patient bearers of the virus HIV and a pattern strain ATCC 18804 were used. The quantification of gene expression was related to the production of hydrolytic enzymes using the quantitative polymerase chain reaction (qPCR) assay. For PDI, we used laser-aluminum-gallium arsenide low power (red visible, 660 nm) as a light source and the methylene blue at 300 μM as a photosensitizer. We assessed two experimental groups for each strain: (a) PDI: sensitization with methylene blue and laser irradiation and (b) control: without sensitization with methylene blue and light absence. The PDI decreased gene expression in 60 % of samples for gene SAP5 and 50 % of the samples decreased expression of LIP9 and PLB2. When we compared the expression profile for of each gene between the treated and control group, a decrease in all gene expression was observed, however no statistically significant difference (Tukey's test/p = 0.12). It could be concluded that PDI (photosensitization with methylene blue followed by low-level laser irradiation) showed a slight reduction on the expression of hydrolytic enzymes of C. albicans, without statistical significance.

Oral carriage of Candida species in HIV-infected patients during highly active antiretroviral therapy (HAART) in Belém, Brazil

OBJECTIVE

To identify the oral carriage of Candida spp in patients infected by human immunodeficiency virus (HIV) and the possible correlation with clinical characteristics.

STUDY DESIGN

Mucosal swab samples collected from 246 patients who were infected by HIV, did not have oral candidiasis, and were being treated with highly active antiretroviral therapy were analyzed. Yeast colonies that developed were identified by using the VITEK 2 automated system.

RESULTS

Candida yeasts were present in 41.87% of the samples, and Candida albicans was the most prevalent (32.52%). Other identified Candida species were C tropicalis (4.88%), C parapsilosis (2.85%), C dubliniensis (0.81%), and C famata (0.81%).

CONCLUSIONS

There was low rate of oral Candida carriage in patients infected by HIV who were on highly active antiretroviral therapy. A greater prevalence of C albicans than non-albicans Candida species was found at the species level. Prior candidiasis predicted the oral carriage of C albicans; however, it did not influence the carriage of non-albicans species. This is the first report of oral carriage of C famata in patients with HIV infection.

Oral candidal carriage, salivary lysozyme levels, and their relationship with CD4 count in HIV-infected patients

AIM

The aim of the present study was to compare the lysozyme concentration and candidal count in saliva between HIV-seropositive and HIV-negative individuals, and to correlate the relationship between lysozyme concentrations, candidal count, and CD4 count in HIV patients.

METHODS

A study was conducted in 90 HIV-seropositive patients (subgroups: 1 [CD4 ≥ 500 cells/μL], 2 [CD4 200-499 cells/μL], and 3 [CD4 ≤ 200 cells/μL] and 30 HIV-negative individuals. A total of 6 mL unstimulated saliva was collected and stored at -80°C. Samples were centrifuged and divided into two portions of 600 μL each. One portion was used for the candidal assay and the other for the lysozyme assay using ready-made kits. Student's independent t-test and Karl Pearson correlation coefficient were used for the statistical analysis.

RESULTS

There was a significant increase (P < 0.001) in lysozyme levels and the candidal count in the saliva of HIV-positive individuals compared with the HIV-negative individuals. A significant increase (P < 0.004) in the salivary candidal count was observed in the HIV subgroups 1-3. There was a significant negative correlation (P < 0.01) between the CD4 and candidal counts in subgroup 1 (P < 0.02) and between the lysozyme concentration and CD4 count in subgroup 3. There was no correlation between the lysozyme concentration and oral candidal carriage.

CONCLUSIONS

An association exists between the lysozyme concentration and specific immunity. Yeast colonization serves as a marker of immunodeficiency in HIV disease progression.

Dynamic analysis of oral Candida carriage, distribution, and antifungal susceptibility in HIV-infected patients during the first year of highly active antiretroviral therapy in Guangxi, China

BACKGROUND

Highly active antiretroviral therapy (HAART) as an effective therapy for immune reconstruction among patients with HIV/AIDS might have influence on oral Candida status. We investigated oral Candida carriage, distribution, and antifungal susceptibility dynamically during the first year of HAART among adult HIV-infected patients in Guangxi, China.

METHODS

Forty-five adult HIV-infected patients who received their first year HAART in the AIDS clinic of the Guangxi Center for Disease Control (CDC) and 31 healthy individuals were recruited. Clinical information and oral examinations were obtained. Oral rinses taken from patients at baseline, 3, 6, 12 months during HAART, respectively, were cultured, and Candida species were identified following standard microbiological techniques. In vitro antifungal susceptibilities were tested by the broth microdilution method.

RESULTS

The oral Candida load decreased gradually in the 45 patients with HIV/AIDS during the first year of HAART (P < 0.050). Among 176 Candida isolates, Candida albicans (114/176) was the predominant species, and Candida parapsilosis (23/62) was the most common non-albicans species. We found the frequency of resistance to fluconazole and itraconazole of Candida isolated from our samples increased (P < 0.05) after 12 months of HAART. In addition, the frequency of C. albicans isolates resistant to fluconazole and itraconazole was on the rise (P < 0.05).

CONCLUSIONS

The Candida load decreased with increased CD4(+) T cell counts, and C. albicans was still the prevailing species. Further, a trend toward more frequent in vitro resistance to fluconazole and itraconazole was observed. Our results provide reference for treatment and prevention of oral candidiasis among this population.

Yeast oropharyngeal colonization in human immunodeficiency virus-infected patients in central taiwan

A prospective, cross-sectional study was conducted at a medical center in central Taiwan to understand the prevalence, associated factors, and microbiologic features for oropharyngeal yeast colonization in human immunodeficiency virus-infected outpatients. Oral yeast colonization was detected in 127 (45 %) patients, including 21 (16.5 %) colonized by more than one species. Of the 154 isolates, Candida albicans was the most common species (114, 74 %), followed by Candida dubliniensis (10, 6.5 %), Candida glabrata (10, 6.5 %), Candida tropicalis (7, 4.5 %), and 13 others. We found that receiving antituberculous drug (p = 0.046) or atazanavir (p = 0.045) was two predictors for patients colonized by non-C. albicans species (p = 0.005) and risking mixed yeast colonization (p = 0.009). Even though our data showed that clinical antifungal drugs remained effective in vitro against the colonizing yeasts, the increased mixed yeast colonization indicates a potential issue for controlling mixed infections in hospital settings.

Oral Candida carriage and immune status in Thai human immunodeficiency virus-infected individuals

Oral candidiasis is a common opportunistic infection among human immunodeficiency virus (HIV)-infected individuals, with growing concerns about the emergence of non-albicans species with resistance to antifungal agents. This cross-sectional study determined the prevalence of oral Candida species in Thai HIV-infected adults and factors affecting their colonization. Candida species were identified from oral rinse samples of 60 HIV-infected participants of the MTCT-Plus initiative and 49 healthy controls by culture-based and molecular assays. The prevalence of oral Candida carriage was similar in HIV-infected patients (56.6 %) and in controls (55.1 %, P = 0.87). Candida albicans was the most predominant species in both groups (94.1 % of Candida carriers in HIV, 88.9 % in control). Interestingly, Candida dubliniensis was the second most common species in controls (29.6 %) and the third in HIV-infected patients (11.8 %, P = 0.08). Multivariate analysis showed that, amongst HIV-infected individuals, CD4 count <200 cells mm(-3) was associated with increased prevalence of oral carriage of both C. albicans (P = 0.03) and non-albicans species (P = 0.03). Moreover, patients with tuberculosis infection had a higher prevalence of the non-albicans species than those without (P = 0.03). Intriguingly, contraceptive use was also associated positively with non-albicans and multi-species carriage (P = 0.04 for both). However, use of antiretroviral drugs protected the patients from Candida carriage (P = 0.03), especially from C. albicans (P = 0.02). In conclusion, while HIV-infected individuals had a similar prevalence of oral Candida carriage to that of the control group, host immune status, tuberculosis infection, and contraceptive use may influence oral colonization of Candida, especially of the non-albicans species.

The association between detectable plasmatic human immunodeficiency virus (HIV) viral load and different subgingival microorganisms in Brazilian adults with HIV: a multilevel analysis

BACKGROUND

This study investigates the association between detectable plasmatic human immunodeficiency virus (HIV) viral load (HVL) and high levels of periodontal- and non-periodontal-related microorganisms in the subgingival microbiota of individuals with HIV.

METHODS

Thirty-seven individuals with HIV were divided into two groups: 1) detectable HVL (n = 15); and 2) undetectable HVL (n = 22). Subgingival biofilm samples were obtained, and the levels of 35 microbial species were determined by the checkerboard DNA-DNA hybridization method. Periodontal clinical measures and laboratory and sociodemographic data were also registered. χ(2) test, Fisher exact test, and Mann-Whitney U test were used to compare groups. Multilevel ordinal regression models were used to test the association between HVL and the levels of 35 microbial species in subgingival biofilm, adjusted for confounders.

RESULTS

Of the 35 species studied, 11 (31.4%) showed higher mean levels in the detectable HVL group than undetectable HVL group (P <0.001). These species included Actinomyces naeslundii II, Actinomyces israelii, Actinomyces odontolyticus, Veillonella parvula, Capnocytophaga gingivalis, Eikenella corrodens, Campylobacter concisus, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Candida albicans. Significant associations between detectable HVL and high levels of microorganisms, adjusted for confounders, were observed for A. naeslundii I, Actinomyces gerencseriae, C. gingivalis, E. corrodens, C. concisus, Prevotella nigrescens, T. forsythia, and Dialister pneumosintes.

CONCLUSION

Detectable plasmatic HVL in individuals with HIV was associated with elevated levels of known periodontal pathogens, such as P. nigrescens, T. forsythia, and E. corrodens, as well as C. concisus, C. gingivalis, and D. pneumosintes in the subgingival biofilm.

Oral microflora and their relation to risk factors in HIV+ patients with oropharyngeal candidiasis

OBJECTIVE

The purpose of this study was to determine the prevalence of oral microflora and association of oral candidiasis and multiple risk factors in HIV(+) patients.

PATIENTS AND METHODS

The present study included 100 HIV-infected patients participated in Imam Khomeini Hospital, Tehran, Iran for Oropharyngeal candidiasis (OPC) and HIV. We assessed the presence or absence of OPC, and samples were obtained from the oral cavity and direct microscopic examination, gram staining and culture on standard microbiological media were performed in all patients. CD4(+) cell count/CD4(+) percentage were also calculated.

RESULTS

The demographic characteristics showed that the patients had a mean age of 32.3 years old, 78% male and 22% female. Patients belonging to 'O(+)' blood group (27%) were more prone to develop OPC. A total of 460 bacterial colonies were obtained and Streptococcus mutans (15.4%) was the most frequently isolated species in the HIV(+) patients, followed by Staphylococcus epidermidis (12.8%) and Corynebacterium (8.7%). In addition, 254 yeasts (from four different genera) were isolated from the patient under study. Candida species (94.4%) were the most frequently obtained genera, followed by Saccharomyces (2.4%), Kluyveromyces and Cryptococcus (1.6% for both) species. Candida albicans (37.2%) was the most common species isolated from HIV(+) patients with OPC and its frequency was significantly higher than that of other Candida species (P<0.05). Candida glabrata, C. dubliniensis, C. tropicalis, C. parapsilosis, C. krusei, C. lusitaniae, C. guilliermondii and C. norvegensis were also identified. Forty percent of the patients had angular cheilitis as the most frequent clinical variant. The mean CD4(+) cell counts were 154.5 cells/μL, with a range of 8 to 611 cells/μL. Thirty percent patients had a CD4(+) cell count between 101 and 200 cells/μL (28.7% of total yeasts isolated). Yeast and bacteria counts did not differ statistically among HIV(+) patients' subgroups with different levels of CD4(+) cells counts.

CONCLUSION

Our results showed that yeasts of the genus Candida were isolated at a comparable rate from the oral cavity of HIV(+) patients and there was no significant difference of the variables CD4(+) cell count and yeast counts. The findings of this study would be helpful in any further study, which, if done prospectively on a large cohort, can be confirmatory.

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

BACKGROUND

Oral 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.

METHODS

Mucosal 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).

RESULTS

The 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.

CONCLUSION

Oral 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.

Smoking as a risk factor for oral candidiasis in HIV-infected adults

OBJECTIVE

We aimed to examine if smoking is an independent predictor of oral candidiasis (OC) among HIV-1 infected persons.

METHODS

The cross-sectional part of this study evaluated 631 adult dentate HIV-1 seropositive persons examined for OC from 1995-2000 at the University of North Carolina Hospitals in Chapel Hill, NC. In the second part, from the above sample, a total of 283 individuals who were free of HIV-associated oral diseases at baseline were followed up for 2 years to assess incident OC events. Data collected from medical record review, interview questionnaires, and clinical examinations were analyzed using chi-squared tests and t-tests. Logistic regression models were developed for prevalent OC employing the likelihood ratio test, whereas Poisson regression models were developed for assessing cumulative incidence of OC. These models included a variety of independent variables to adjust for confounding.

RESULTS

Thirteen percent of participants had OC only; 4.6% had OC with Oral Hairy Leukoplakia; and 69.7% had neither. Smoking was associated with OC in all models [prevalent OC - current smokers: logistic regression - Odd ratio (95% CI) = 2.5 (1.3, 4.8); Incident OC - current smokers: Poisson regression (main effects model) - Incidence rate ratio (95% CI) = 1.9 (1.1, 3.8)]. Other Poisson regression models suggested evidence for effect modification between CD4 cell count and incident OC by smoking.

CONCLUSION

Smoking is an independent risk factor for the development of OC in HIV-1 infected persons, and the risk of OC is modified by CD4 cell count which measures strength of the immune system.

Predisposing factors for oropharyngeal colonization of yeasts in human immunodeficiency virus-infected patients: a prospective cross-sectional study

BACKGROUND

Oropharyngeal candidiasis continues to be a major opportunistic infection in human immunodeficiency virus (HIV)-infected patients. The objectives of this study were to investigate the prevalence, associated factors, and microbiologic features for oropharyngeal yeast colonization in HIV-infected patients.

METHODS

From October to December 2009, consecutive HIV-infected patients older than 18 years were recruited in this study. Demographic information, underlying conditions, and clinical histories were collected. Oropharyngeal swab cultures for yeasts and antifungal drug susceptibilities of the isolates were performed.

RESULTS

Of the 105 HIV-infected patients, 54 (51.4%) were colonized with yeasts, including 11 patients (20.4%) with more than one species. Among the 68 isolates, Candida albicans accounted for 73.5%, followed by Candida tropicalis (5.9%), Candida glabrata (5.9%), and Candida dubliniensis (4.4%). There were 7.5% and 6% Candida isolates resistant to fluconazole and voriconazole, respectively. All of the Candida isolates were susceptible to amphotericin B. A higher prevalence of yeast colonization was noted in patients with a CD4 cell count ≤200 cells/μL (p = 0.032). Multivariate regression analysis showed that intravenous drug use was an independent associated factor for oropharyngeal yeast colonization (odds ratio, 5.35; 95% confidence interval, 1.39-20.6; p = 0.015), as well as protease inhibitor-containing antiretroviral therapy (odds ratio, 3.59; 95% confidence interval, 1.41-9.12; p = 0.007).

CONCLUSION

Despite previous studies showing that protease inhibitors decreased Candida adhesion to epithelial cells in vitro, the current study found protease inhibitor-containing antiretroviral therapy predisposed to oropharyngeal yeast colonization in HIV-infected patients.

In vitro Antifungal Susceptibility Patterns of Candida Albicans from HIV and AIDS Patients Attending the Nylon Health District Hospital in Douala, Cameroon

HIV and AIDS are major public health problems in Cameroon where the HIV prevalence is 5.5%. Candidiasis is the leading opportunistic mycosis in HIV and AIDS patients. The objective of this study was to determine the in vitro antifungal susceptibility pattern of Candida albicans in HIV and AIDS patients to eight antifungal agents in the Nylon Health District of Douala in Cameroon. Three hundred and four HIV and AIDS patients were recruited between March and August 2007 to participate in a cross-sectional study. All subjects who fulfilled the inclusion criteria were enrolled. Informed consent was obtained from all subjects before samples were collected. Three samples comprising oral swabs, vagina/urethra swabs and a mid-stream urine were collected from each subject. Specimens were cultured on sabouraud dextrose agar and C. albicans isolates were identified using the germ tube technique. The disk diffusion method was used for antifungal susceptibility testing using eight antifungal agents. The prevalence of candidiasis in the study population was 67.8% (95% CI: 62.5-73.1%) and that of C. albicans was 42.8% (95% CI: 37.2-48.4%). Oral swabs had the highest prevalence of C. albicans followed by vaginal/urethral samples (52.6% vs. 29.7% respectively). Forty (30.8%) subjects had C. albicans infection at more than one collection site. There was a statistically significant difference in the infectivity of C. albicans with age, sex and site of infection (P<0.05). C. albicans isolates were most sensitive to ketoconazole (80%) followed by econazole (64.6%) while fluconazole and 5-flurocytosin recorded the poorest sensitivities (22.9% vs 24.6%, respectively). There was a statistically significant difference in the sensitivity pattern of antifungal agents with respect to the site of isolation of the organism (P<0.05). Ketoconazole is the drug of choice for the treatment of C. albicans infection in HIV and AIDS patients in the Nylon Health District of Douala, Cameroon.

A Comparative Study of Oral Candidal Carriage and Its Association with CD4 Count between HIV-Positive and Healthy Individuals

Aims and Objectives:

To correlate asymptomatic oral candidal carriage in HIV-positive patients and normal individuals and determine its association with CD4 count.

Material and Methods:

Forty HIV-positive patients and forty healthy individuals were included in this study. Saliva from both groups was collected by the spitting method. The saliva from each individual was incubated aerobically on Sabouraud Dextrose agar with antibiotics at 37°C. The germ tube method was used for differentiation of candidal species, whether the Candida albicans or non- Candida albicans. Surface count method was used to count the number of colonies of candida species. Data were analyzed by chi square and Mann-Whitney test.

Results:

Oral candidal carriage was found in 22 out of 40 (55%) HIV-positive patients. In healthy volunteers, oral candidal carriage was found in 6 out of 40 (15%) individuals ( p value = 0.0002), which is significantly higher. Similarly, density carriage in the HIV-positive patients was found to be significantly higher than that in the HIV-negative group ( p value = 0.002). However, oral yeast carriage was not associated with CD4 count (correlation coefficient r = −0.087).

Conclusion:

Within the limits of the study, we concluded oral candidal carriage rate and density carriage higher in HIV-positive patients than in healthy individuals.

Hosting infection: experimental models to assay Candida virulence

Although normally commensals in humans, Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Candida krusei are capable of causing opportunistic infections in individuals with altered physiological and/or immunological responses. These fungal species are linked with a variety of infections, including oral, vaginal, gastrointestinal, and systemic infections, with C. albicans the major cause of infection. To assess the ability of different Candida species and strains to cause infection and disease requires the use of experimental infection models. This paper discusses the mucosal and systemic models of infection available to assay Candida virulence and gives examples of some of the knowledge that has been gained to date from these models.

New approaches to Candida and oral mycotic infections: Workshop 2A

This workshop reviewed aspects of the following: oral fungal disease in HIV-infected patients and the predictive value of oral mucosal disease in HIV progression; the role of the oral biofilms in mucosal disease; microbial virulence factors and the pseudomembranous oral mucosal disease process; the role that oral mucosal disease may have in HIV transmission; and the available topical antifungal treatment. This article summarizes the ensuing discussions and raises pertinent problems and potential research directions associated with oral fungal disease in HIV-infected patients, including the frequency of oral candidosis, the role of the intraoral biofilm in the development of oral mucosal disease, and host-pathogen interactions, as well as the development of the fetal oral mucosa, neonatal nutrition, and the role of oral candidosis in this setting. Finally, discussions are summarized on the use of inexpensive effective antifungal mouthwashes in resource-poor countries, the potential stigmata that may be associated with their use, as well as novel topical medications that may have clinical applicability in managing oral candidal infections in HIV-infected patients.

Characterization of yeasts colonizing in healthy individuals

Opportunistic yeast pathogens may switch from harmless commensal to pathogenic relationships with the host under different conditions. They usually cause superficial infections, but may be the agents of more significant infections in immunocompromised patients. To investigate yeast colonization in the oral cavities of clinically healthy individuals, we collected oral swabs from 323 students and staff at the National Health Research Institutes, Taiwan. A total of 49 (15.2%) volunteers were colonized by low levels of yeasts and of these, only 3 (6.1%) were co-colonized by more than one species. Among the 52 isolates, comprising seven fungal genera and 13 species, Candida albicans (57.7%) was the dominant species, followed by Candida parapsilosis (15.4%). There was only one isolate of C. parapsilosis that showed, in vitro, a high (2 μg/ml) minimum inhibitory concentration (MIC) to amphotericin B. There were six (11.5%) isolates with fluconazole MICs ≥ 64 μg/ml and all of them were non-Candida species. With the exception of Cryptococcus albidus, the remaining five isolates had voriconazole MICs ≥ 4 μg/ml. In addition, there was one C. albicans isolate with relatively high fluconazole (32 μg/ml) and voriconazole (4 μg/ml) MICs.

Oropharyngeal colonization of HIV-infected outpatients in Taiwan by yeast pathogens

Among 234 isolates comprising 26 different Candida species colonizing the oropharynx of 181 (54.3% of 399 surveyed) HIV-infected outpatients, 27 (11.7%) were fluconazole resistant. Antibacterial treatment was associated with increased rates of yeast colonization, while antiretroviral therapy and pneumococcal vaccination protected patients from yeast colonization.

Photodynamic inactivation of normal and antifungal resistant Candida species

BACKGROUND

Susceptibility of bacterial and fungal species to the photodynamic killing effects of various photosensitizing dyes has received increasing attention. In the oral cavity oral candidiasis is primarily caused by Candida albicans. Evidence suggests that Oropharyngeal Candidiasis, found frequently in patients with immunodeficiency, present with mixed Candida organisms and are more difficult to treat than those solely due to C. albicans. In the present study we demonstrate the ability to efficiently kill antifungal resistant isolates of Candida using Photofrin induced PDT.

METHODS

Candida strains from the ATCC as well as fluconazole and amphotericin B resistant and sensitive isolates from adults with AIDS were grown cultures and grown under standard conditions. Photofrin was added to appropriate cultures as dictated by experimental design. Light was delivered to assigned cultures using a 630 nm laser source at a power density of 150 mW/cm(2), for appropriate time to deliver 45-135 J/cm(2). Colony forming assays were used to determine survival.

RESULTS

After illumination cultures treated with Photofrin had significant reduction in colony forming ability at all light doses examined. Isolates from AIDS patients which had demonstrated antifungal resistance showed equivalent sensitivity to photodynamic killing as did control ATCC cultures of the same strain.

CONCLUSION

This study demonstrates Photofrin induced PDT can eliminate Candida species with significant efficiency as revealed by colony forming ability. Further Candida isolates from AIDS patients that had demonstrated fluconazole and amphotericin B resistance were equally susceptible to photodynamic killing.

Oral distribution of Candida species and presence of oral lesions in Brazilian leprosy patients under multidrug therapy

OBJECTIVE

The aim of this study was to evaluate the prevalence of Candida spp. and presence of oral lesions in Brazilian leprosy patients under multidrug therapy (MDT).

METHODS

Thirty-eight individuals (18 males and 20 females, median age 53 years) clinically and microbiologically diagnosed as leprosy (lepromatous variant), and under MDT for at least 45 days were studied. The control group constituted by 38 healthy individuals (median age 53.5), matched to the test group in relation to age, gender and oral conditions. Oral rinses were collected and the Candida identification was performed by phenotypic tests. The existence of Candida dubliniensis among the isolates was analyzed using a validated multiplex PCR assay. Twenty-nine leprosy patients were examined intra-orally for the presence of lesions. Data were analyzed by z- and Mann-Whitney tests (alpha = 5%).

RESULTS

Yeast carriage rate between leprosy patients (65.8%) and controls (47.4%) was similar (P = 0.099), and no significant difference between yeast counts was observed (P = 0.1004). Candida albicans was the most frequently isolated species in both groups. In the leprosy group, Candida tropicalis and Candida parapsilosis were also identified. In the control group, we additionally identified Candida tropicalis, Candida glabrata and Candida kefyr. Candida dubliniensis was not detected. No leprosy-related oral lesion was registered.

CONCLUSION

Within the limits of the study, we concluded that Brazilian leprosy patients under MDT showed similar levels of carriage and Candida species distribution in relation to the controls.

Carriage of Candida species in oral cavities of HIV infected patients in South India

Fifty-four patients with human immunodeficiency virus (HIV) infection were studied to assess the load of oral carriage of Candida spp. The mean oral Candida carriage density (30,305.93 +/- 56,643.93 CFU ml(-1)) in HIV patients was significantly higher than that seen in the control population (93.48 +/- 358.48 CFU ml(-1); P = 0.000). The mean Candida load in HIV patients with oral thrush (46,591.43 +/- 65,002.57 CFU ml(-1)) was significantly higher than in the HIV subjects without oral thrush (306.32 +/- 699.50 CFU ml(-1); P = 0.000). Non-C. albicans Candida species (56%) were more predominant than the C. albicans (44%) isolates. 25S rDNA PCR analysis of C. albicans revealed preponderance of genotype A strains. Interestingly, 42.6% of rinse specimens grew multiple Candida species, with the combination of C. albicans and C. krusei (39.1%) being the most frequent.

Oral yeast carriage in HIV-infected and non-infected populations in Rosario, Argentina

The objectives of the present study were: (i) to assess the frequency of oral colonisation by Candida species in HIV-positive patients and to compare it with a population of HIV-negative individuals, (ii) to determine the prevalence of C. dubliniensis in both populations and (iii) to determine the susceptibility of C. dubliniensis and other Candida species isolated from HIV-positive patients to the most commonly used antifungal agents. Oral samples were obtained from 101 HIV-positive and 108 HIV-negative subjects. For yeast identification, we used morphology in cornmeal agar, the API 20C Aux, growth at 45 degrees C, d-xylose assimilation, morphology in sunflower seed agar and PCR. The frequency of isolation of Candida in HIV-positive patients was: C. albicans, 60.7%; C. dubliniensis, 20.2%; C. glabrata, 5.6%; C. krusei, 5.6%; C. tropicalis, 4.5%; others, <5%. The frequency of isolation of Candida in HIV-negative patients was: C. albicans, 73.9%; C. tropicalis, 15.5%; C. dubliniensis, 2.1%; C. glabrata, 2.1%; C. parapsilosis, 2.1%; others, <5%. The oral colonisation by yeast in the HIV-positive patients was higher than that in the HIV-negative subjects. The susceptibilities of 42 Candida isolates to three antifungal agents were determined. All isolates of C. dubliniensis were susceptible to fluconazole, although several individuals had been previously treated with this drug. Out of the 42 Candida isolates, 10 presented resistance to fluconazole and 10 to itraconazole. The presence of Candida species, resistant to commonly used antifungal agents, represents a potential risk in immunocompromised patients.

Asymptomatic oral carriage of Candida species in HIV-infected patients in the highly active antiretroviral therapy era

Oropharyngeal candidiasis is the most common opportunistic fungal infection in individuals infected with human immunodeficiency virus. CD4+ lymphocytes count and the quantification of viral RNA in blood plasma have been found to be the main markers of HIV disease progression. The present study was conducted to evaluate Candida sp. diversity in the oral cavity of HIV-infected patients and to determine whether there was association of CD4+ cell count and viral load with asymptomatic oral Candida carriage. Out of 99 HIV-positive patients studied, 62 (62.6%) had positive culture for Candida (oral carriage) and 37 patients (37.4%) had Candida negative culture (no oral carriage). The etiologic agents most common were C. albicans and C. tropicalis. The range of CD4+ was 6-2305 cells/mm3 in colonized patients and 3-839 cells/mm3 for non-colonized patients, while the viral load was 60-90016 copies/mL for colonized patients and 75-110488 copies/mL for non colonized patients. The viral load was undetectable in 15 colonized patients and in 12 non colonized patients. Our results showed that there was no significant difference of the variables CD4+ cell count and viral load between oral candida carriage and no oral candida carriage patients.

Effect of antifungal treatment on the prevalence of yeasts in HIV-infected subjects

Oral candidiasis, the most common opportunistic infection in patients with HIV infection, is usually associated with Candida albicans. Several factors may influence the carriage of Candida, including immunocompromised conditions and HIV infection, colonization by yeasts from different geographical areas and antimycotic treatment. This study investigated the Candida carrier rate, level and types of yeast in HIV-positive and -negative subjects, and the effect of previous exposure to antifungal drugs on the level of yeasts in HIV-positive patients in Gauteng, South Africa. Unstimulated saliva was collected from 332 HIV-positive patients and 100 HIV-negative subjects and cultured for yeasts. The number and species of yeast were determined. HIV-positive patients who carried yeasts were divided into two groups depending upon their previous antifungal drug exposure, and the level of Candida carriage in each group was compared. The Candida carrier rate in the HIV-positive patients (81.3%) was slightly higher than previously reported and significantly higher (P<0.001) than in the HIV-negative group (63%). The carrier rate in the HIV-negative group was also higher than in earlier studies. Fourteen per cent of the HIV-positive patients carried more than 10,000 c.f.u. ml-1 whereas none of the HIV-negative subjects carried this large a number of yeasts (P<0.001). Seventy per cent of the yeasts were identified as C. albicans and approximately 30% as non-albicans species. In conclusion, the Candida carrier rate is higher in the South African population than elsewhere. HIV-positive patients carry more and a greater variety of yeasts than HIV-negative subjects. Exposure to antifungal drugs has no effect on the level of yeast carriage in HIV-positive patients.

Salivary gland function in HIV-infected patients treated with highly active antiretroviral therapy (HAART)

OBJECTIVE

This study was undertaken to determine if HAART alters salivary oral host defense in HIV(+) men.

STUDY DESIGN

Whole, parotid, and submandibular/sublingual saliva was collected from 39 healthy men and 147 HIV(+) patients with mild to moderate immune dysfunction (69 treated with HAART [HAART(+)]; 78 not treated [HAART(-)]). Salivary flow rates, anticandidal activities, electrolytes, and antimicrobial/antifungal proteins were determined.

RESULTS

While CD4(+) cell counts were not different between the HIV(+) groups, the median viral load for HAART(-) was 15 times greater than HAART(+). For both HAART groups, salivary yeast carriage rates and concentration were comparable and both showed similar reductions in salivary flow rates. Salivary anticandidal activities were not altered. Saliva composition of both HIV(+) groups was different from control, but only uric acid in parotid saliva of HAART(+) differed from HAART(-).

CONCLUSIONS

HAART does not adversely affect inherent salivary oral host defense in HIV(+) patients with mild to moderate immune dysfunction.

Association of asymptomatic oral candidal carriage, oral candidiasis and CD4+ lymphocyte count in HIV-positive patients in China

OBJECTIVES

To compare the prevalence of asymptomatic oral candidal carriage in healthy volunteers with human immunodeficiency virus (HIV)-positive patients in China, as well as to investigate the relationship between CD4+ lymphocyte count and oral candidal colonization or oral candidiasis.

METHODS

Oral candidal carriage and oral candidiasis were investigated in 101 patients with HIV-infection seen at Youan Hospital, Beijing, China. Two hundred and seventeen healthy volunteers were involved as a control. Culture from saliva was used to test for the presence of oral Candida. CD4+ lymphocyte count was measured by flow cytometry. All data were analyzed statistically by SAS.

RESULTS

Asymptomatic oral candidal carriage rate (28.6%) in HIV-positive group was similar to that in the healthy group (18.0%; P = 0.07). No significant difference in CD4+ lymphocyte count was found between oral Candida carriers and non-carriers among HIV-positive subjects (P = 0.89). However, the frequency of oral candidiasis increased with the decrease in CD4+ lymphocyte count (P < 0.0001), and pseudomembranous candidiasis was predominant in HIV-positive patients with CD4+ <200 cells microl(-1) (66.7%).

CONCLUSIONS

In HIV-positive subjects, asymptomatic oral candidal colonization is not related to CD4+ lymphocyte count of blood, and the carriage rate is similar to that in the healthy population. Oral candidiasis is more likely to be observed in HIV-positive patients who have a low CD4+ lymphocyte count.

Invasive Candidiasis in Immunocompromised Hospitalized Patients

The frequency of infections by Candida species is increasing worldwide, with candidemia representing the fourth most common bloodstream infection in the U.S. The risk of infection is especially high in the immunocompromised, hospitalized patient. The treatment of and prophylaxis for Candida infection have led to the emergence of resistant species and the acquisition of resistance in previously susceptible species. Current therapeutic options include amphotericin B and its lipid compounds, fluconazole, itraconazole, voriconazole, and caspofungin. Research is focusing on better diagnostics and the evaluation of strategies such as prophylaxis in high-risk hosts and pre-emptive therapy.