Prevalence of oral Candida carriage in Thai adolescents

Oral candidiasis and cigarette, tobacco, alcohol, and opium consumption in Rafsanjan, a region in the southeast of Iran

BACKGROUND

We investigated the association between oral candidiasis prevalence and cigarette, tobacco, alcohol, and opium consumption in Rafsanjan, a region in the southeast of Iran.

METHODS

This cross-sectional study was conducted using the data of Oral Health Branch of Rafsanjan Cohort Study (OHBRCS) as a part of the Rafsanjan Cohort Study (RCS). RCS included in Prospective Epidemiological Research Studies in IrAN (PERSIAN) was begun in 2015 in the Rafsanjan. A full-mouth examination was done by trained dental specialists. Oral candidiasis was diagnosed based on clinical examination. Information about cigarette, tobacco, and opium smoking and alcohol consumption were collected based on data from self-reported questionaries. Univariate and multivariate dichotomous logistics regression were used to assess the association between oral candidiasis and cigarette, tobacco, alcohol, and opium consumption.

RESULTS

Among 8682 participants with mean age of 49.94 years, the prevalence of oral candidiasis was 7.94%. There was a direct association between cigarette smoking in current and former cigarette smokers with an increased odds of oral candidiasis (OR: 3.26, 95% CI: 2.46-4.33 and OR: 1.63, 95% CI: 1.18-2.25 respectively) in fully adjusted models. There was a dose-response relationship between the odds of oral candidiasis and dose (OR: 3.31, 95% CI: 2.38-4.60), duration (OR: 2.48, 95% CI: 2.04-3.95) and number (OR: 3.01, 95% CI: 2.02-4.50) of cigarette smoking in the 4th quartile compared to reference group.

CONCLUSIONS

A dose-response relationship was shown between cigarette smoking and increased odds of oral candidiasis.

Profiling of potential pulmonary fungal pathogens and the prevalence of the association between pulmonary tuberculosis and potential fungal pathogens in presumptive tuberculosis patients referred to Saint Peter's Specialized Tuberculosis Referral Hospital, Addis Ababa, Ethiopia

Objective

The burden of pulmonary fungal infection is increasing and often misdiagnosed as pulmonary tuberculosis in developing countries where the prevalence of pulmonary tuberculosis is high. |Therefore, the purpose of this study is to determine the spectrum of potential pulmonary fungal pathogens and the prevalence of the association between pulmonary tuberculosis and potential fungal pathogens.

Materials and methods

A cross-sectional study was conducted between October 2018 and May 2019. Sputum was collected from 636 study participants. Part of the sputum was inoculated onto Brain Heart Infusion agar, and fungi were identified following standard microbiological procedures. The remaining part of the sample was used for the investigation of pulmonary tuberculosis.

Results

Among 636 sputum samples, 75.9% (483) and 25.6% (163) were positive for potential fungal pathogens and pulmonary tuberculosis, respectively. The prevalence of the association between pulmonary tuberculosis and potential fungal pathogens was 20.0%. Of fungal isolates, 81.4% were yeasts. The remaining 128 (18.6%) isolates were molds. The isolation rate of fungi was higher in males (51.6%) than in females (48.4%). There was no statistically significant association between the prevalence of potential pulmonary fungal pathogens and sex (p = 0.239). Patients in the age group of 35 to 44 and above were slightly more affected than younger age groups. The association between potential fungal pathogens and age was not statistically significant (p = 0.50).

Conclusion

High prevalence of potential pulmonary fungal pathogens and the association of tuberculosis and potential fungal pathogens recorded in this study will enforce health personnel to pay due attention to these conditions and arise the interest of researchers to conduct further work on the burden of the association between tuberculosis and potential fungal pathogens. Our study also revealed the need to employ conventional microbiology tests along with clinical and radiological evidence since clinical manifestations and radiological pictures of tuberculosis mimic that of pulmonary fungal infection.

Microbial interactions and immunity response in oral Candida species

Oral candidiasis are among the most common noncommunicable diseases, related with serious local and systemic illnesses. Although these infections can occur in all kinds of patients, they are more recurrent in immunosuppressed ones such as patients with HIV, hepatitis, cancer or under long antimicrobial treatments. Candida albicans continues to be the most frequently identified Candida spp. in these disorders, but other non-C. albicans Candida are rising. Understanding the immune responses involved in oral Candida spp. infections is a key feature to a successful treatment and to the design of novel therapies. In this review, we performed a literature search in PubMed and WoS, in order to examine and analyze common oral Candida spp.-bacteria/Candida-Candida interactions and the host immunity response in oral candidiasis.

Hyposalivation, oral health, and Candida colonization in independent dentate elders

Hyposalivation is an important problem in elders and could interfere with several oral functions and microbial ecology. While the number of independent elders who retain more natural teeth increases worldwide, few studies examined hyposalivation in this population. Thus, this study aims to examine relationships between hyposalivation, oral health conditions and oral Candida colonization in independent dentate elders and evaluate factors associated with salivary flow and Candida carriage. We conducted a cross-sectional study in fifty-three dentate elders (≥65 years old with at least 4 pairs of posterior occlusal contacts) with no, or well-controlled, systemic conditions. Participants were interviewed for medical history, subjective dry mouth symptoms, oral hygiene practices and denture information. Unstimulated and stimulated salivary flow rates, objective dry mouth signs, gingival, tongue-coating, and root-caries indices were recorded. Stimulated saliva was cultured on Sabouraud-dextrose agar for Candida counts. Candida species were identified using chromogenic Candida agar and polymerase chain reaction. Statistical significance level was set at p<0.05. The results showed that hyposalivation was associated with higher gingival and tongue-coating indices (p = 0.003 and 0.015, respectively), but not root-caries index. Hyposalivation was also associated with higher prevalence of oral Candida colonization (p = 0.010; adjusted OR = 4.36, 95% confidence interval = 1.29–14.72). These two indices and Candida load were negatively correlated with unstimulated and stimulated salivary flow rates. Interestingly, non-albicans Candida species were more prevalent in denture wearers (p = 0.017). Hence, hyposalivation is a risk factor for poorer oral health and oral Candida colonization in independent dentate elders. Because of its potential adverse effects on oral and systemic health, hyposalivation should be carefully monitored in elders.

Efficacy of gel-based artificial saliva on Candida colonization and saliva properties in xerostomic post-radiotherapy head and neck cancer patients: a randomized controlled trial

Objective

To evaluate the efficacy of an edible artificial saliva gel, oral moisturizing jelly (OMJ), and a topical commercial gel (GC dry mouth gel) on Candida colonization and saliva properties.

Materials and methods

This study was a secondary analysis of a single-blinded randomized controlled trial conducted in xerostomic post-radiotherapy head and neck cancer patients. Candida colonization, stimulated salivary flow rate (SSFR), saliva pH, and buffering capacity (BC) were measured at 0, 1, and 2 months after each intervention. Candida colonization was quantified by colony counts and species identified by Candida Chromagar, polymerase chain reaction, and API 20C AUX system. Statistical significance level was 0.05.

Results

A total of 56 participants in OMJ (N = 30) and GC (N = 26) groups completed the study. OMJ significantly increased saliva pH (p = 0.042) and BC (p = 0.013) after 1-month use, while GC only improved saliva pH (p = 0.027). Both interventions tended to increase SSFR but only GC had a significant increase at 2 months (p = 0.015). GC and OMJ significantly decreased the number of Candida species at 1 and 2 months, respectively. Both groups tended to reduce Candida counts but not significant.

Conclusions

Both OMJ and GC saliva gels could improve saliva pH and decrease the number of Candida species. OMJ is superior to GC in its buffering capacity, while GC may better improve salivary flow rate. Long-term and large-scale study is warranted to test the efficacy of artificial saliva in oral health improvement.

Clinical relevance

OMJ and GC gel could decrease the number of Candida species and improve saliva properties in post-radiation xerostomic patients.

Trial registration number

Clinicaltrials.gov NCT03035825. Date of registration: 25th January 2017.

Candida coinfection among patients with pulmonary tuberculosis in Asia and Africa; A systematic review and meta-analysis of cross-sectional studies

Diagnosis of fungal co-infections in patients suffering from pulmonary tuberculosis has critical importance. Therefore, we aimed to determine the prevalence of candida coinfection in patients with pulmonary tuberculosis. The present systematic review of cross-sectional studies was conducted based on the Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISMA) Protocol. Studies published online in English from January 2001 to March 2019 were assessed. Literature search was done in Web of Science, MEDLINE/PubMed, and Scopus databases and search engines using keywords combinations of "pulmonary fungi", "pulmonary coinfection", OR "pulmonary mycosis", "pulmonary fungal infections/agents", OR "polymicrobial infection", OR "secondary infection", OR "mixed infections", "pulmonary candidiasis", "fungi coinfection", "fungal co-colonization", AND "pulmonary tuberculosis", OR "pulmonary TB", AND "Asia", AND "Africa". Data was analyzed using Comprehensive Meta-Analysis software (CMA). Heterogeneity between studies was evaluated by Cochran's Q and I² tests. The pooled prevalence of candida coinfection among patients with pulmonary tuberculosis was 25.7% (95% CI: 23.7-27.9). C. albicans was the most prevalent Candida spp. with a pooled prevalence of 65.8% (95% CI: 54.3-75.7). Risk factors of candida coinfection were smoking, diabetes, advanced age, and low body mass index. The present review showed a high rate of candida coinfection among patients suffering from pulmonary tuberculosis. So, appropriate measures are necessary to early diagnose and treat these infections.

Oral Candida colonization in xerostomic postradiotherapy head and neck cancer patients

OBJECTIVES

To evaluate (a) oral colonization of Candida species, especially for non-albicans Candida species (NACS), in xerostomic postradiotherapy head and neck cancer patients and (b) risk factors affecting their colonization.

MATERIALS AND METHODS

Subjective and objective dry mouth scores, stimulated salivary flow rates, pH and buffering capacity were measured in 72 xerostomic postradiotherapy head and neck cancer patients. Candida counts and species identification were performed using oral rinse samples cultured in Candida Chromagar, followed by polymerase chain reaction and API 20C AUX system.

RESULTS

Candida colonization was observed in 87.5% of subjects, with 80.6% and 48.6% of study population colonized by C. albicans and NACS, respectively. NACS was associated with high objective dry mouth scores, denture use, and females (p = .006, .009, and .036, respectively). In addition, Candida glabrata was detected more in females (p = .018) and denture wearers (p = .026), while Candida tropicalis was associated with high objective dry mouth scores (p = .022) and females (p = .027). Quantity of Candida colonization correlated positively with objective dry mouth scores (r = 0.599, p < .001) and negatively with salivary flow rates (r = -0.258, p = .041) and pH (r = -0.290, p = .022).

CONCLUSION

NACS colonization was common in xerostomic head and neck cancer patients. Increased signs of dry mouth, female and dental prostheses may promote NACS colonization.

Adherence and Cytotoxicity of Candida spp. to HaCaT and A549 cells

Candida species are opportunistic fungal pathogens that cause superficial or invasive infections. Recently, the incidence of infection by non-Candida albicans species, especially Candida glabrata, has increased. In this study, we analyzed the adhesion and cytotoxicity of various Candida spp. that are part of the normal human microbiota. C. albicans adheres well to cell culture plates and to cultured cells. C. glabrata selectively adheres to epithelial cells rather than to cell culture plates. Candida parapsilosis insufficiently adheres to confluent monolayers of human lung epithelial A549 and keratinocyte HaCaT cells. We then analyzed the cytotoxicity of C. albicans and C. glabrata, which adhered well to epithelial cells. C. glabrata has been found to cause more damage to A549 cells than to HaCaT cells, suggesting that resident Candida spp. have distinct cytotoxic effects in different tissues. It is important to clarify the properties of Candida spp. as there is evidence that normal microbiota can cause infections. Our data suggest that it is necessary to use appropriate cell lines for characterizing the adherence and cytotoxicity of Candida spp.

Acrylic orthodontic retainer is not a risk factor for focal Candida colonization in young healthy patients: a pilot study

BACKGROUND

Denture enhances the risk of Candida colonization because of adherence to acrylic base and interference with salivary rinsing. Acrylic orthodontic appliances may also create retentive areas for food debris and microbial pathogens; moreover, patients are instructed to use the retainers at night, when salivary secretion is reduced. We studied the Candida colonization in orthodontic patients using acrylic retainer.

METHODS

Participants were orthodontic patients with full compliance during the retention phase with no signs or symptoms or being at risk for Candida, divided into users of (a) Hawley retainer (study group) and (b) other retainers (vacuum-formed/fixed bonded retainer; control group). Collected data included demographic characteristics and habits. Samples were collected from palate mucosa, cultured and incubated (28°C) for 3 days. Positive Candida species were recultured to identify the Candida species.

RESULTS

Fifty-one patients participated (mean age 20.9 ± 9.6 years); 22 had maxillary Hawley retainer and 29 had maxillary vacuum-formed/fixed bonded retainer. Candida albicans colonization in the hard palate was identified in 2 patients (3.9%)-1 (4.5%) from the Hawley retainer study group and 1 (3.4%) from the control group.

CONCLUSIONS

The hypothesis that palatal coverage by acrylic orthodontic retainer might enhance Candida colonization on the palatal mucosa is not supported by this pilot study.

Candida concentrations determined following concentrated oral rinse culture reflect clinical oral signs

BACKGROUND

Oral candidiasis is an infection caused by a yeast-like fungus called Candida. Various methods can be used to isolate Candida from the oral cavity. However, it is difficult to correctly and satisfactorily diagnose oral candidiasis because currently no microbiological or laboratory standards based on samples from the oral cavity are available. The aim of this study is to establish a reliable laboratory test for diagnosing oral candidiasis.

METHODS

Oral swab, rinse and concentrated rinse samples were obtained from 200 consecutive outpatients (103 male patients and 97 female patients; mean age, 47.2 years; age range, 9-89 years). Candida colonies from cultured samples were enumerated to compare the sensitivities and specificities of the above sampling methods, and the associations between Candida detection or concentration and the clinical oral signs were examined.

RESULTS

The mean colony numbers were 263 ± 590 CFU/swab for the swab method, 2894 ± 6705 CFU/100 μL for the rinse method, and 9245 ± 19,030 CFU/100 μL for the concentrated rinse method. The median numbers were 23 CFU/swab for the swab method, 56 CFU/100 μL for the rinse method, and 485 CFU/100 μL for the concentrated rinse method. Candida was detected in the oral cavity of 33.5 % and 52.0 % of the outpatients by the swab method and concentrated rinse, respectively. Candida concentrations determined by the concentrated rinse were closely related to the severity of the clinical oral signs. The positive predictive values of residual root, redness of the oral mucosa, denture, glossalgia, dry mouth, and taste disorder were useful predictors of oral candidiasis.

CONCLUSIONS

Concentrated rinse sampling is suitable for evaluating oral candidiasis, and Candida concentrations examined using this method strongly associated with the oral signs associated with Candida infection.

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.

Prevalence of Candida co-infection in patients with pulmonary tuberculosis

BACKGROUND

Candida species are emerging as a potentially pathogenic fungus in patients with broncho-pulmonary diseases. The synergistic growth promoting association of Candida and Mycobacterium tuberculosis has raised increased concern for studying the various Candida spp . and its significance in pulmonary tuberculosis patients during current years.

AIMS

This study was undertaken with the objective of discovering the prevalence of co-infection caused by different Candida species in patients with pulmonary tuberculosis.

METHOD

A total of 75 patients with pulmonary tuberculosis diagnosed by sputum Ziehl-Neelsen staining were included in the study. Candida co-infection was confirmed using the Kahanpaa et al. criteria. Candida species were identified using gram stain morphology, germ tube formation, morphology on cornmeal agar with Tween-80, sugar fermentation tests and HiCrome Candida Agar.

RESULTS

Candida co-infection was observed in 30 (40%) of patients with pulmonary tuberculosis. Candida albicans was the most common isolate observed in 50% of the patients with co-infection, followed by C. tropicalis (20%) and C. glabrata (20%). Candida co-infection was found in 62.5% of female patients, while it was observed in only 29.4% of the male patients (P value 0.0133). Mean ± SD age of the patients with C. glabrata infection was 65.83 ± 3.19, while the mean ± SD age of the patients with other Candida infections was 43.25 ± 20.44 (P value 0.0138).

CONCLUSION

Many patients with pulmonary tuberculosis have co-infection with Candida spp. The prevalence of non-albicans Candida species is increasing and may be associated with inadequate response to anti-tubercular drugs. C. glabrata infection has a strong association with old age.