HIV感染者口腔念珠菌负荷及生物型研究

目的调查人类免疫缺陷病毒（human immunodeficiency virus，HIV）感染者口腔中念珠菌负荷状况、生物分型及与口腔念珠菌病临床表现的关系。方法采取漱口法对64例HIV感染者和42名健康对照者进行口腔念珠菌的定量分离培养，并综合利用革兰染色、厚壁孢子生成实验、CHROMagar显色培养和API 20C AUX酵母菌鉴定系统对分离株进行生物型鉴定。结果64例HIV感染者中，52例中可分离出念珠菌74株，阳性分离率为81．3％，而42名健康对照者口腔念珠菌阳性分离率仅为16．7％（P〈0．001）。通过对74株念珠菌的生物型进行鉴定，发现有39株白色念珠菌，15株热带念珠菌及其他6个生物型20株。健康对照组中，分离出5株白色念珠菌和其他裂2株。结论HIV感染者口腔念珠菌感染率明显增加，其口腔念珠菌的检出率和负荷量亦明显增加，白色念珠菌和热带念珠菌为其主要分离菌；与健康对照组相比，HIV感染者的口腔念珠菌分离株生物类型旱现多样化。     

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.     

The prevalence of oral candidiasis in HIV-infected individuals and dental attenders in Edinburgh

This study prospectively assessed the prevalence of oral candidal carriage and oral candidiasis in known HIV-seropositive individuals (n = 121) and other dental attenders in Edinburgh (n = 614). Candida species were isolated from 57.4% of dental attenders and 93.4% of HIV-seropositive subjects. Clinical evidence of oral candidiasis was observed in 6% and 52%) of these groups respectively, erythema-tous forms of candidiasis being the commonest in both groups.     

Carriage of Candida species in the oral cavity in diabetic patients: relationship to glycaemic control

To study the possible relationship between the quality of glycaemic control in diabetes mellitus and the carriage of Candida species, the candidal carrier status of 412 diabetic patients was examined using an oral rinse technique and correlated with measurements of random blood glucose and total glycosylated haemoglobin. Candida was isolated in 210 diabetics (51%) with 13 patients (6%) carrying more than one species. The positive isolates were: Candida albicans (89%), Candida krusei (2.8%), Candida glabrata (2.8%), Candida tropicalis (6.2%), Candida stellatoidea (2.8%) and Candida parapsilosis (0.5%). No association was identified between carriage rates and the type of treatment of diabetes, or with the quality of glycaemic control. As in non-diabetic subjects, the carriage rates were higher in diabetic patients wearing dentures. Thus, the oral carriage of Candida in diabetic patients was independent of glycaemic control but in certain sub-groups the carriage rates were higher, and involved uncommon candidal species.     

Betel quid-associated oral lesions and oral Candida species in a female Cambodian cohort

BACKGROUND: Betel quid chewing (BQC) is still prevalent among elderly Cambodian women and is associated with a wide variety of oral mucosal lesions. BQC has also been associated with a reduced rate of dental caries and changes in the oral microbiological flora. METHODS: Since no studies were available on the impact of BQC on the oral carriage of Candida species, in this study oral swabs (Fungiquick, Hain Diagnostika, Germany) were taken from the tongue and palate of 48 Cambodian women with BQC habit (study group) and 13 control subjects without BQC habit (control group) to determine the spectrum of Candida species in these two groups. In addition, we investigated lesions of the oral mucosa likely to be associated with BQC habit in both study and control groups. RESULTS: The median duration of BQC was 10 years (range 10 months-30 years). The following oral lesions were found in the study group: betel chewer's mucosa (85.4%), oral leukoplakia (8.3%), leukoedema (37.5%) and oral lichen planus (4.2%). Oral candidiasis was seen neither in BQ-chewers nor in controls. Candida spp. were found in 70.8% of the cases (controls 69.2%). Whilst C. albicans was isolated from 27.1% of the study cohort, C. tropicalis was the second most common isolate. One control case was colonised by C. dubliniensis--the first report of this organism from a Cambodian population. There was no significant difference in the candidal carriage rate or the Candida species isolated between the study and the control group. CONCLUSIONS: Mycological findings from the present study do not indicate that BQC has a significant effect on oral colonisation by Candida species.     

Prevalence of Candida species in Turkish children: relationship between dietary intake and carriage

In this study, the prevalence and intensity of Candida species were evaluated in 300 healthy Turkish children aged between 0 and 12 years. The candidal carriage in 26 children who were fed only with breast milk and 38 children who were fed with both breast milk and bottle milk or other fluids was also examined. Oral samples cultured for fungal growth and Candida species were identified using germ tube test, chlamydospore formation test and API 20C AUX system. The results demonstrated that the prevalence of oral candidal carriage in 300 healthy children was 26.3%. Candida albicans was the most frequently isolated yeast (84.8% of the isolates). The other yeasts were identified as Candida parapsilosis, Candida krusei, Candida kefyr, Candida famata, and Candida tropicalis. It was also observed that the frequency of carriage varied as a function of age. The prevalence of carriage in children who were fed with both breast milk and bottle milk or other fluids was 18.5%, while in children fed only with breast milk was 0%. This finding supports previously reported observations that there may be intrinsic differences in oral carriage of Candida species between different ages and populations and type of dietary intake may affect frequency of carriage.     

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

OBJECTIVES. We sought to assess asymptomatic oral carriage of Candida species and relative density in human immunodeficiency virus-infected (HIV+) subjects, as well as to determine whether yeast carriage is associated with CD4+ cell count, HIV-1 RNA quantity, gender, route of HIV transmission, antiretroviral therapy, or smoking. STUDY DESIGN. A cross-sectional analysis of oral rinses from HIV+ and healthy subjects was undertaken. Oral candidal carriage and relative species were investigated in 42 HIV+ and 41 healthy individuals, all of whom were seen at the Palermo University Department of Oral Sciences, Italy. Data were managed and analyzed by means of the computer software package StatView 5.0.1. RESULTS. Carriage rate was 61.9% and 29.3% (P =.003) among HIV+ and healthy subjects, respectively. Similarly, density carriage in the HIV+ group was found to be significantly higher than in the control group (P = .0002). Among HIV+ subjects, Candida carriage was significantly associated with smoking, whereas density was not. Oral candidal carriage and relative density were not significantly associated with the other 4 parameters evaluated. Candida albicans was the most frequently recovered species. CONCLUSIONS. Asymptomatic candidal carriage and relative density were found to be significantly higher in the oral cavity of HIV+ subjects-but not associated with CD4+ counts or HIV-1 RNA quantities.     

Carriage of Candida species in the oral cavity in diabetic patients: relationship to glycaemic control

To study the possible relationship between the quality of glycaemic control in diabetes mellitus and the carriage of Candida species, the Candidal carrier status of 412 diabetic patients was examined using an oral rinse technique and correlated with measurements of random blood glucose and total glycosylated haemoglobin. Candida was isolated in 210 diabetics (51%) with 13 patients (6%) carrying more than one species. The positive isolates were: Candida albicans (89%), Candida krusei (2.8%), Candida glabrata (2.8%), Candida tropicalis (6.2%), Candida stellatoidea (2.8%) and Candida parapsilosis (0.5%). No association was identified between carriage rates and the type of treatment of diabetes, or with the quality of glycaemic control. As in non-diabetic subjects, the carriage rates were higher in diabetic patients wearing dentures. Thus, the oral carriage of Candida in diabetic patients was independent of glycaemic control but in certain sub-groups the carriage rates were higher, and involved uncommon candidal species.     

Effect of cannabis use on oral candidal carriage

The effects of cigarette smoking on oral candidal carriage and candidosis have been well documented but few similar studies on cannabis smoking have appeared, therefore it was felt that such a study needed to be undertaken. In this investigation, the effect of cannabis smoking combined with methaqualone and tobacco on candidal prevalence, density and candidosis was examined in 55 users. Age and sex matched tobacco-smoking (n = 58) and non-smoking controls (n = 50) were examined similarly. The imprint culture technique was used for harvesting Candida. Results showed an increased prevalence and density of C. albicans in cannabis users while there was no apparent difference in the prevalence of candidiasis. However, two subjects presented with oral multifocal candidiasis.     

In vitro evaluation of virulence attributes of Candida spp. isolated from patients affected by diabetes mellitus

BACKGROUND: Diabetes mellitus is a common disease found worldwide and it has been previously suggested that oral candidal infections may be more frequent or severe in patients with this disease. Systemic and local factors may influence the balance between the host and yeasts, and favour the transformation of Candida isolates from commensal to pathogenic microorganisms. Candida species have developed specific virulence mechanisms that confer the ability to colonise host surfaces, to invade deeper host tissue, or to evade host defences. Few studies have investigated the expression of the virulence attributes of oral Candida isolates in patients with diabetes mellitus. MATERIAL AND METHODS: The in vitro extracellular proteinase production and the in vitro ability to adhere to fibronectin of 229 Candida isolates of two geographic different groups of patients with diabetes mellitus and of healthy subjects were assessed. RESULTS: Candida isolates of patients with diabetes mellitus expressed a higher ability to adhere than those of healthy subjects. Higher levels of adhesion were also recorded in patients with a lower oral Candida colonisation. No differences were observed in the in vitro expression of extracellular proteinase of Candida isolates of patients with diabetes mellitus and those of non-diabetic subjects. Isolates of patients with type 2 diabetes mellitus expressed greater levels of proteinase than isolates of type 1 diabetes mellitus. CONCLUSIONS: Diabetes mellitus could be considered as an additional variable that may influence not only oral Candida carriage but also the ability of isolates to enhance the expression of virulence attributes.     

The relationship between oral hygiene and oral colonization with Candida species in healthy adult subjects*

To cite this article:
Int J Dent Hygiene
DOI: 10.1111/j.1601‐5037.2009.00371.x
Darwazeh AM‐G, Hammad MM, Al‐Jamaei AA. The relationship between oral hygiene and oral colonization with Candida species in healthy adult subjects. Abstract: Poor oral hygiene has been frequently suggested as a predisposing factor for oral candidal colonization, but the convincing evidence is lacking. Objective: To assess and compare oral candidal colonization, both quantitatively and qualitatively, in groups of healthy dentate subjects with different levels of oral hygiene as determined by the plaque index (PI) and gingival index (GI) scores. Methods: The concentrated oral rinse technique was used to isolate Candida species from 149 healthy dentate subjects. Candida species were cultured on Sabouraud’s dextrose agar plates and identified by germ‐tube test and the automated Vitek® system biochemical yeast card. According to the PI and GI scores, subjects were divided into different groups of oral hygiene level. Results: Candida species were isolated from 86 (57.7%) subjects. The prevalence of candidal carriage increased significantly as a function of age (P = 0.023), but was comparable between males and females (58.7% and 56.7% respectively; P = 0.87). Oral candidal carriage rate and density were not affected by the levels of dental plaque or gingival condition. The prevalence of oral candididal carriage was significantly higher in the subjects who were not using dental floss compared with those who were using dental floss (P = 0.032). Conclusion: Oral hygiene status, as determined by the PI and the GI scores per se, does not affect oral candidal colonization in healthy dentate subjects.     

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 (α = 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.     

Isolation of Candida species from the oral cavity and fingertips of complete denture wearers.

STATEMENT OF PROBLEM: Candida species usually colonize in the oral cavity of denture wearers and may also colonize on their fingers because of frequent manual manipulation of the dentures. PURPOSE: This study investigated the association between oral and fingertip candidal isolation in a group of denture wearers. MATERIAL AND METHODS: Oral rinse and fingerprints obtained from 25 healthy male complete denture wearers were microbiologically investigated for candidal growth, and isolated Candida species were identified with a germ tube test and a commercially available yeast identification system. Denture cleanliness, hand washing, and denture wearing and handling habits were recorded for each subject. RESULTS: Candida species were isolated from the oral cavity of 15 (60%) and fingertips of 11 (44%) subjects. Ten (66.7%) subjects had concomitant oral and fingertip candidal isolation, whereas 5 (33.3%) subjects had only oral Candida (P=.005). CONCLUSION: The hands of denture wearers who had oral Candida were significantly more colonized with Candida species than oral Candida-free subjects. Further studies identifying Candida species to the strain level and the significance of hand Candida as a source for mouth reinfection are needed.     

The effects of orthodontic appliances on Candida in the human mouth

Background.  Candida is an opportunistic pathogen present in about 50–60% of the healthy human population, and becomes pathogenic when the host immune defence is undermined such as in HIV infection. Adhesion and colonization of the oral cavity by Candida albicans is an initial step in candidosis, and the presence of orthodontic and other oral appliances seems to alter the oral ecological environment, hence may tip the balance to favour the candidal presence.
Objective.  The purpose of this paper was to review the literature with specific attention to prevalence; intra-oral density of the candidal organisms; and Candida carriage status in orthodontic patients before, during, and after treatment.
Conclusions.  The limited amount of literature demonstrated that the density of Candida increases; the most common Candida species isolated in the orthodontic patients was C. albicans ; and that there seems to be a direct relationship between the presence of a removable appliance, Candida , and low salivary pH levels. No healthy patients developed Candida infection from the orthodontic appliances. However, there seems to be a trend that some non- Candida carriers converted to Candida carriers following the insertion of the appliances by unknown mechanism. This may indicate a more cautious approach when providing orthodontic treatments to immunocompromised children concerning the possible increased risk of candidal infection.     

Oral Candida infection and colonization in solid organ transplant recipients

Introduction:  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.
Methods:  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.
Results:  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.
Conclusions:  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.     

Oral manifestation of chronic mucocutaneous candidiasis: seven case reports

BACKGROUND: Chronic mucocutaneous candidiasis (CMC) is a rare disorder characterized by persistent or recurrent candidal infections of the skin, nails and mucous membranes or by a variable combination of endocrine failure as well as immunodeficiency. Oral clinicopathological features of CMC have seldom been described in detail. METHODS: Seven patients with CMC were reported in the study. The clinical and histological findings, etiological Candida species, immunological evaluation, and therapeutic pattern of oral lesions, were analyzed. RESULTS: Long-standing whitish hyperplastic and nodule-like lesions with exaggerated deep fissure were the typical and characteristic oral manifestations presented by all patients. The tongue was the most common site affected. Histologically, no obvious distinction was found between CMC and other forms of candidal infection. Abnormal proportions of T-lymphocyte subsets and positive titers of autoantibody were observed in three subjects (42.9%) and one patient (14.3%) respectively. Meanwhile, four subjects (57.1%) showed decreased albumin and increased globulin, three cases (42.9%) had high levels of ESR. But no iron deficiency was found. Candida albicans was the microorganism isolated from these patients. CONCLUSIONS: Multiple and widespread candidal infectious lesions can be observed on the oral cavity of CMC patients. Hyperplastic and nodule-like lesion with irremovable whitish patches and deep fissure are the most common oral manifestations of these patients. Dentists, otolaryngologists and pediatricians should be familiar with the clinical appearances of CMC to make an accurate diagnosis. Potential systemic disorders should be concerned to avoid the reoccurrence of oral candidiasis.     

Alteration of humoral responses to Candida in HIV infection

The objectives of this preliminary study were to determine the prevalence of oral candidal carriage and infection in a group of HIV-positive individuals and compare the humoral immune responses in serum and saliva in this group with a control group of HIV-negative subjects. Patients were examined clinically with particular reference to the presence of candidal lesions and oral swabs taken to identify carriers. Venous blood and whole saliva were obtained for estimation of total and anti-Candida antibody levels. Pseudomembranous candidiasis was the commonest clinical variant in HIV-positive individuals. Candida albicans was the commonest species isolated in both groups. Increased levels of anti-Candida IgG were found in both serum and saliva of HIV-negative individuals who were either carriers of Candida species or had clinical candidiasis. This was associated with a reciprocal fall in anti-Candida IgA. Similar trends were seen in HIV-positive individuals in association with candidal carriage and infection, although the changes were more marked.     

Prevalence of oral methicillin-resistant Staphy/ococcus aureus in an institutionalized veterans population

Methicillin-resistant Staphylococcus aureus ( MRSA) is a nosocomial pathogen now of great concern in nursing homes and other institutional settings. MRSA has been well-documented to inhabit the nares, skin wounds, and respiratory tract, but little is known about its presence in the oral cavity. In this study, all patients admitted to an 80-bed VA extended care facility were cultured weekly for 12 weeks to detect the presence of MRSA in the nares, wounds, in-dwelling devices, and the oral cavity. Of a total of 107 participating subjects, 20 cultured positive for oral MRSA, yielding a prevalence of 18.7%, compared with 19.6% prevalence in the nares —the traditionally accepted screening site for MRSA. There was a 91.6% agreement between oral and nasal carriage in subjects, but four of 107 subjects (3.7%) cultured positive for oral MRSA without evidence of nasal carriage. These results suggest that oral MRSA may be more common than previously thought in high-risk settings, with a prevalence comparable with that of nasal infection. Further investigation is necessary to characterize the factors associated with the presence of MRSA in the oral cavity     

Influence of oral conditions on colonization by highly toxigenic Staphylococcus aureus strains

Oral Diseases (2012) 18 , 402–409 Objectives: As the oral cavity is regarded as a relevant site for Staphylococcus aureus colonization and interhuman transmission, this study aimed to investigate whether different oral conditions influence the rates of S. aureus oral carriage and genetic characters of S. aureus isolates. Subjects and methods: Staphylococcus aureus was searched in samples collected from cheek, gingival margin, and anterior nares of 45 healthy subjects, 27 periodontitis affected subjects, and 29 subjects with fixed prosthetic restorations. Isolates were screened for 17 genetic determinants, and Partial Least Square Discriminant Analysis was performed to evaluate whether specific characters correlated with oral condition or site of isolation. Results: The three subject groups showed comparable nasal carriage rates but, both the periodontitis and prosthetic restoration groups showed significantly higher oral carriage rates, as compared to healthy subjects (P = 0.01 and 0.02, respectively). Moreover, periodontitis affected subjects hosted strains possessing a distinct genotypic and phenotypic background, characterized by the presence of a larger number of exotoxins encoding genes. Conclusions: These data confirm that the oral cavity is an important site of S. aureus colonization and demonstrate that conditions modifying the oral environment, as the presence of periodontitis and of fixed prosthetic restorations, promote S. aureus carriage and may favor the spread of more pathogenic strains.     

Prevalence of oral Candida species in leprosy patients from Cambodia and Thailand

BACKGROUND: Leprosy is a chronic bacterial infection which may lead to significant orofacial morbidity. However, reports on the oral mycotic flora of leprosy patients are rare. The aim of the current study was to explore the oral yeast carriage in two groups of leprosy patients. METHODS: 40 Cambodian (seven men, 33 women) and 48 Thai (14 men, 34 women) leprosy patients from Leprosy Rehabilitation Centre Khien Kleang, Phnom Penh, Cambodia and McKean Rehabilitation Center, Chiangmai, Thailand were randomly selected and their demographic data and clinical history were recorded. Tongue and palatal swabs of each patient were collected using sterile Fungi-Quick swabs (Hain Diagnostika, Nehren, Germany) and they were cultured aerobically on Sabouraud's dextrose agar and CHROMAgar (CHROMagar, Paris, France). Yeast were identified by germ tube, chlamydospore production, and assimilation tests (API 20C AUX, Bio-Merieux, Marcy l'Etoile, France) and reconfirmed using APILAB Plus system (Bio-Merieux). RESULTS: Two groups (Cambodian and Thai) had median age of 35 and 64 years. They had been with leprosy for median durations of 17.7 and 38.9 years (P<0.05), respectively. Overall yeast carriage in two cohorts were 80% and 93.75%. Candida albicans had highest carriage rate in either group (65.6%, 44.4%). Candida krusei and C. glabrata existed as second-line colonizers after C. albicans. Candida glabrata carriage was significantly higher in Thai patients (P<0.05). Multispecies carriage was seen in three Cambodian (9.4%) and five Thai (11.5%) patients. CONCLUSIONS: This study indicates high oral yeast carriage in leprosy patients. Candida albicans remains predominant while C. krusei and C. glabrata are second-line oral colonizers. Co-inhabitation of multiple yeast species is also noted in these patients' oral mycotic flora.