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.     

Implantation of Candida albicans and other Candida species in the oral cavity of rats

The carriage of five Candida species in the mouths of normal and siaioadenectomised rats was determined for periods up to 30 days after inoculation into the oral cavity. In both test and control animals. Candida albicans was the species recovered in greatest quantities at all periods, followed by C. parapsilosis and C. tropicalis. In contrast. C. gullliermondii and C. krusei were isolatable only in small numbers and only from the 1st up to the 5th day; they were not present thereafter. Sialoadenectomy favoured oral colonisation only by C. albicans ( P <0.05) and did not influence the carriage of the other species.     

Colonization of the oral cavity by Candida species: risk factors in long-term geriatric care

The population of elderly people in hospitals for long-term geriatric care presents many risk factors for nosocomial infection by Candida species. The aim of this work was to reduce the risk of C. albicans nosocomial infections starting from colonization of the oral cavity. The population of concern was the patients in long-stay geriatrics units; a sample of 110 people was selected by drawing lots. The clinical and biological parameters of each patient included in the study were recorded. The oral cavity was colonized by Candida spp in 67% of cases. The distribution of the strains showed that C. albicans was the most frequently identified strain, followed by C. glabrata; of the 73 patients with at least one strain of Candida spp., 47 had a clinically diagnosed candidiasis (64.4%). The wearing of dentures was not statistically linked with the development of oral candidiasis. Detecting which patients have been colonized, identifying the risk factors and applying preventive measures should reduce the probability of elderly people falling into the vicious circle of infection-malnutrition-immune-depression.     

Presence of Candida spp. in the oral cavity of heart transplantation patients

Candida spp. can lead to infections or even fungal sepsis particularly among immunocompromized individuals.

Objective

The aim of the present study was to analyze the presence of Candida spp. among patients subjected to orthotopic heart transplantation.

Material and Methods

Oral rinses from 50 patients subjected to orthotopic heart transplantation, aged 13 to 70 years, 40 males and 10 females, were examined. Sexage-oral conditions matched-control included 50 individuals who were not subjected to any kind of transplantation and were not immunocompromized for any other reason. Counts of yeasts were expressed as median values of logarithm of cfu/mL and were statistically compared by Mann-Whitney’s test. The heart transplant and control groups were compared for the presence of Candida spp. by chi-square test (p<0.05).

Results

The results showed statistically significant difference (p=0.001) in the prevalence of Candida spp. between the transplantation and control groups. Counts of yeasts (cfu/mL) in the transplanted group were significantly higher than in the control group (p=0.005). Candida albicans was the most prevalent species isolated from both groups.

Conclusion

It was concluded that Candida yeast counts were higher in the heart transplant recipients than in the controls. There was higher variation of Candida species among the heart transplant patients and the most frequently isolated samples were: Candida albicans, Candida glabrata and Candida tropicalis. Isolates of Candida dubliniensis was not found in either of the groups.     

Fluconazole-resistant Candida species in the oral flora of fluconazole-exposed HIV-positive patients

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

Papillary lesions of the oral cavity: relationship to human papillomaviruses

Human papillomaviruses are a group of genetically related organisms that infect stratified squamous epithelium. Unlike many other viruses that infect oral epithelium and induce lysis of the cells they penetrate, HPVs induce proliferative changes in these cells that result in both benign and malignant tumors. The common skin wart (verruca vulgaris) is induced by HPV 2 and 4. Genital warts (condylomas) and the common solitary oral papilloma are associated with HPV 6 and 11. Either HPV 13 or 32 causes focal epithelial hyperplasia. All of these wart-like lesions are benign growths of the stratified squamous lining of the oral cavity and lips and can be treated by surgical excision or laser ablation. HPV 16 and other less frequently encountered genotypes are associated with uterine cervix cancer in 95 percent to 98 percent of cases, and the evidence for a causal role is robust. There are emerging data that implicate HPV in certain subsets of oral cancer, particularly those that arise in the oropharynx/tonsillar region. Some instances of the various histologic subtypes subsumed under proliferative verrucous leukoplakia and verrucous carcinoma also harbor HPV.     

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.     

Isolation and identification of Candida from the oral cavity

A number of methods of sampling the oral cavity for the presence of candida have been developed. Such techniques play an important role in the diagnosis and management of oral candidosis. In the past, identification of candida isolated from the oral cavity has usually been limited to the genus Candida or to the species C. albicans. However, with the recognition that Candida species differ in the production of putative virulence factors and sensitivity to antifungal agents, greater emphasis has been placed on identification of isolates to species level. As a result a range of commercially available systems for yeast identification can now be used in conjunction with traditional identification procedures.     

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.     

Improved oral hygiene and Candida species colonization level in geriatric patients

OBJECTIVES: This work consists in improving oral hygiene (OH) for elderly dependent people in long-term hospital care, in order to decrease the degree of colonization and the associated risk of developing oral candidiasis. As this population frequently suffers from such colonization and because it is difficult to install and practice OH care, a study protocol was designed at the request of geriatricians. The objective of the present study was to set up a programme of OH, applied by the care staff, and to monitor oral colonization of by Candida spp. BASIC RESEARCH DESIGN: We compared the levels of hygiene and Candida spp. colonization for a group of 110 long-term patients in geriatric departments at T1, when clinical data were collected and oral mycological samples taken before the OH protocol was applied, and at T2, during the postprotocol phase after 3 months of application, when the clinical data and sample collection were repeated. RESULTS: During these 3 months 11 patients died. These patients were excluded from the results, which are presented for matched series of the 99 patients still present at T2. Statistical analysis comparing the clinical and biological parameters at T1 and T2 established that there had been an improvement in OH: the 'adequate' level was reached for 72.4% of patients at T2 compared with 41.8% at T1 (P < 0.001) and the 'very inadequate' level was observed for 9.2% at T2 compared with 27.9% at T1 (P < 0.01). A reduction was observed in the number of patients showing the highest degree of C. albicans and C. glabrata colonization (> 50 colony forming units) from 41.9% at T1 to 24.9% at T2 (P < 0.05) and from 56.4% at T1 to 13.0% at T2 (P < 0.05) respectively. The number of patients with candidiasis fell significantly from 43.2% at T1 to 10.2% at T2. CONCLUSIONS: The OH protocol led to an overall decrease in Candida spp. colonization, a significant reduction in the number of candidiasis and an improvement in the level of oral and denture hygiene but vigilance is still necessary concerning OH care and the initial training of staff in specific care of the mouth.     

Close association between oral Candida species and oral mucosal disorders in patients with xerostomia

Oral Diseases (2012) 18, 667-672 Objective: Heightened interest in oral health has lead to an increase in patients complaining of xerostomia, which is associated with various oral mucosal disorders. In this study, we investigated the relationship between Candida species and oral mucosal disorders in patients with xerostomia. Subjects and Methods: We evaluated whole salivary flow rate and presence of oral mucosal disorders in 48 patients with xerostomia and 15 healthy controls. The number of Candida species was measured as colony-forming units after propagation on selective medium. Identification of Candida at the species level was carried out by polymerase chain reaction and restriction fragment length polymorphism analysis. We then examined the relationship between Candida species and oral mucosal symptoms. Results: Compared with controls, patients with xerostomia exhibited significantly decreased whole salivary flow rate, increased rate of oral mucosal symptoms, and higher numbers of Candida. Salivary flow rate negatively correlated with the number Candida. Among patients with oral candidiasis, Candida albicanswas isolated from the tongue mucosa and Candida glabratawas isolated from the angle of the mouth. Conclusion: These results suggest that particular Candida species are involved in the pathogenesis of oral mucosal disorders in patients with xerostomia.     

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.     

A strip test for detecting Candida in the oral cavity.

One-hundred and twenty persons were screened for the presence of Candida in the mouth. Salivary samples were cultured on Sabouraud's agar, on yeast extract, and on Microstix. Microstix is a new and simple method testing for Candida. The reliability of the strip for detecting clinically identified candidiasis in severely ill patients was 100 per cent. Of ninety-three clinically healthy controls, forty-five were found to be Candida carriers according to the two conventional methods (Sabouraud's agar and yeast extract), but only forty-one of them by the strip. The discrepancy might be explained by the limit of the sensitivity of the strip (5.10(2) yeast per milliliter). The strip is recommended for testing clinically suspected candidiasis and is very useful for screening.     

Susceptibility of oral Candida species to calcium hydroxide in vitro.

AIM: The susceptibility of common oral Candida species to saturated aqueous calcium hydroxide solution was studied. METHODOLOGY: The yeast species tested were C. albicans (16 strains). C. glabrata (three strains), C. guilliermondii (three strains), C. krusei (two strains), and C. tropicalis (two strains). At least one reference strain of each species was used; the others were clinical isolates either from persistent apical periodontitis or from marginal periodontitis. The susceptibility of Enterococcus faecalis (ATCC 29212) was studied for comparative purposes. Standardized inocula of the strains were incubated in aqueous calcium hydroxide solution, pH 12.4, for time-periods ranging from 5 min to 6 h. Volumes of 0.1 mL of the test suspension were cultured directly on Brucella blood agar and incubated in air at 37C. The plates were inspected for growth at 24 and 48 h and the colonies were counted. The time required to reduce the number of colony-forming units to less than 0.1% of the initial number was determined for each strain. RESULTS: The sensitivity of the C. albicans strains was generally low, with 16 h of incubation required to kill 99.9% of the colony-forming units. No differences in susceptibility between C. albicans strains isolated from root-canal infections and from periodontitis were found. Both strains of C. tropicalis were killed between 3 and 6 h of incubation, whilst strains of C. guilliermondii were killed after only 1020 min of incubation. All strains of C. glabrata survived 20 min, but not 1 h, of incubation, whilst 13 h were required to kill C. krusei. Compared with E. faecalis, all Candida spp. showed either equally high or higher resistance to aqueous calcium hydroxide. CONCLUSIONS: This study indicates that Candida spp. are resistant to calcium hydroxide in vitro, which may explain the isolation of yeasts from cases of persistent apical periodontitis.