Potential Pathogenicity of Candida Species Isolated from Oral Cavity of Patients with Diabetes Mellitus

In Vitro Evaluation of the Virulence Attributes of Oropharyngeal Candida Species Isolated from People Living with Human Immunodeficiency Virus with Oropharyngeal Candidiasis on Antiretroviral Therapy

Background

Oropharyngeal Candida species are part commensal microflora in the the oral cavity of health individuals. Commensal Candida species can become opportunist and transition to pathogenic causes of oropharyngeal candidiasis (OPC) in individuals with impaired immunity through ecological cues and expression of virulence factors. Limited studies have evaluated virulence attributes of oropharyngeal Candida species among people living with human immunodeficiency virus (PLHIV) with OPC on antiretroviral therapy (ART) in Uganda.

Objective

Evaluation of the Virulence Attributes of Oropharyngeal Candida Species Isolated from People Living with Human Immunodeficiency Virus with Oropharyngeal Candidiasis on Antiretroviral Therapy.

Methods

Thirty-five (35) Candida isolates from PLHIV with OPC on ART were retrieved from sample repository and evaluated for phospholipase activity using the egg yolk agar method, proteinase activity using the bovine serum albumin agar method, hemolysin activity using the blood agar plate method, esterase activity using the Tween 80 opacity test medium method, coagulase activity using the classical tube method and biofilm formation using the microtiter plate assay method in vitro.

Results

Phospholipase and proteinase activities were detected in 33/35 (94.3%) and 31/35 (88.6%) of the strains, respectively. Up to 25/35 (71.4%) of the strains exhibited biofilm formation while esterase activity was demonstrated in 23/35 (65.7%) of the strains. Fewer isolates 21/35 (60%) of the strains produced hemolysin and coagulase production was the least virulence activity detected in 18/35 (51.4%).

Conclusion

Phospholipase and proteinase activities were the strongest virulence attributes of oropharyngeal Candida species.

Stephanoascus ciferrii Complex: The Current State of Infections and Drug Resistance in Humans

In recent years, the incidence of fungal infections in humans has increased dramatically, accompanied by an expansion in the number of species implicated as etiological agents, especially environmental fungi never involved before in human infection. Among fungal pathogens, Candida species are the most common opportunistic fungi that can cause local and systemic infections, especially in immunocompromised individuals. Candida albicans (C. albicans) is the most common causative agent of mucosal and healthcare-associated systemic infections. However, during recent decades, there has been a worrying increase in the number of emerging multi-drug-resistant non-albicans Candida (NAC) species, i.e., C. glabrata, C. parapsilosis, C. tropicalis, C. krusei, C. auris, and C. ciferrii. In particular, Candida ciferrii, also known as Stephanoascus ciferrii or Trichomonascus ciferrii, is a heterothallic ascomycete yeast-like fungus that has received attention in recent decades as a cause of local and systemic fungal diseases. Today, the new definition of the S. ciferrii complex, which consists of S. ciferrii, Candida allociferrii, and Candida mucifera, was proposed after sequencing the 18S rRNA gene. Currently, the S. ciferrii complex is mostly associated with non-severe ear and eye infections, although a few cases of severe candidemia have been reported in immunocompromised individuals. Low susceptibility to currently available antifungal drugs is a rising concern, especially in NAC species. In this regard, a high rate of resistance to azoles and more recently also to echinocandins has emerged in the S. ciferrii complex. This review focuses on epidemiological, biological, and clinical aspects of the S. ciferrii complex, including its pathogenicity and drug resistance.

In vitro comparison of antifungal activity of conventional alcohol sprays and antimicrobial photodynamic therapy on acrylic denture resin

BACKGROUND

Traditionally, alcohol sprays are used for disinfection of acrylic-base denture surfaces. A limited number of studies have assessed the role of antimicrobial photodynamic therapy (aPDT) in this regard; however, it remains debatable whether conventional alcohol sprays are superior to aPDT in terms of antifungal activity or vis versa.

OBJECTIVE

The aim of the present in vitro study is to compare the antifungal activity of conventional alcohol sprays and aPDT on acrylic denture resin.

METHODS

Individuals wearing complete dentures at least on one arch were included. Dentures were randomly divided into three groups. Groups 1-3 were disinfected with an alcohol-based antiseptic spray and aPDT, respectively. Assessment of oral yeast growth was done using swab samples. The culture mediums were incubated at 37∘C for 72 hours and viewed through a microscope. The numbers of colony forming units (CFU/ml) were determined. P< 0.05 were considered statistically significant.

RESULTS

At baseline, the mean CFU/ml in Groups 1-3 were comparable. After disinfection, a statistically significant reduction in microbial CFU/ml was observed in Groups 1 (P< 0.05) and 2 (P< 0.05) compared with baseline. In Group 3, there was no difference in CFU/ml throughout the study. After disinfection, there was no difference in microbial CFU/ml in dentures in Groups 1 and 2.

CONCLUSION

Conventional alcohol sprays are as effective as aPDT towards reducing oral yeasts CFU/ml on acrylic denture resin.

Phenotypic Investigation of Virulence Factors, Susceptibility to Ceragenins, and the Impact of Biofilm Formation on Drug Efficacy in Candida auris Isolates from Türkiye

Candida auris has emerged as a significant fungal threat due to its rapid worldwide spread since its first appearance, along with its potential for antimicrobial resistance and virulence properties. This study was designed to examine virulence characteristics, the efficacy of ceragenins, and biofilm-derived drug resistance in seven C. auris strains isolated from Turkish intensive care patients. It was observed that none of the tested strains exhibited proteinase or hemolysis activity; however, they demonstrated weak phospholipase and esterase activity. In addition, all strains were identified as having moderate to strong biofilm formation characteristics. Upon determining the minimum inhibitory concentrations (MIC) of ceragenins, it was discovered that CSA-138 exhibited the highest effectiveness with a MIC range of 1-0.5 µg/mL, followed by CSA-131 with a MIC of 1 µg/mL. Also, antimicrobial agents destroyed mature biofilms at high concentrations (40-1280 µg/mL). The investigation revealed that the strains isolated from Türkiye displayed weak exoenzyme activities. Notably, the ceragenins exhibited effectiveness against these strains, suggesting their potential as a viable treatment option.

The Associations of Auto-Brewery Syndrome and Diabetes Mellitus: A Literature Review and Clinical Perspective

Endogenous production of alcohol without the external intake of alcohol is called auto-brewery syndrome (ABS), and to get its levels to rise to a level that it has physical symptoms of alcohol intake is rare. The most common cause of ABS is the metabolism of ingested carbohydrates by intestinal microflora. This occurrence does not happen in all normal individuals but only in some high-risk individuals. Patients with diabetes mellitus (DM) have been hypothesized to be at high risk for ABS. We searched databases, such as PubMed, Medline, and PubMed Central, to search for existing literature with relevant keywords. In the finalized review, we have included 30 relevant articles. Alcohol formed in the gut gets absorbed in the bloodstream and immediately gets metabolized, so usually it does not achieve a level in blood high enough to cause symptoms. In high-risk patients, there is an increase in the level of bloodstream alcohol above a certain level, so it shows symptoms. Because there is higher blood glucose in DM, the patients have been shown to be at increased risk for developing ABS. Similarly, obesity is also a risk factor for DM, making it a high-risk condition for ABS. The most involved pathogens are Candida and Saccharomyces.

Phenotypic and genotypic characterization of virulence markers and antifungal susceptibility of oral Candida species from diabetic and non-diabetic hemodialysis patients

BACKGROUND

Patients with chronic kidney disease undergoing hemodialysis are often colonized by Candida species with high possibility of fungal infections. The purposes of this study were to determine the prevalence of Candida species, evaluate antifungal susceptibility profile, biofilm formation, proteinase and phospholipase activities, and the frequency of virulence genes in the Candida species isolated from the oral mucosa of hemodialysis diabetic (DM) and non-diabetic (non-DM) patients.

METHODS

This study identified several species of Candida isolated from 69 DM and 58 non-DM patients on hemodialysis using phenotypic methods and PCR-RFLP technique. The identification of C. albicans and C. glabrata complex was performed by HWP1 gene and four oligonucleotides (UNI-5.8S, GLA-f, BRA-f, and NIV-f), respectively. Antifungal susceptibility to amphotericin B, fluconazole, itraconazole, voriconazole, and caspofungin was assessed according to CLSI M27-A3/S4. The biomass, metabolic activity of biofilm, proteinase (P_rz), phospholipase (P_z), and molecular study for virulence genes were assessed using crystal violet, XTT assay, agar-based hydrolytic enzyme, and PCR technique, respectively.

RESULTS

Candida prevalence was 44.9% with 47.8% and 41.4% among DM and non-DM patients, respectively (P = .045). The species identified were C. albicans (49.5%), C. glabrata (16.5%), C. tropicalis (12%), C. kefyr (8.8%), C. parapsilosis (6.6%), C. dubliniensis (3.3%), and C. lusitaniae (3.3%). The antifungal susceptibility profile showed that all Candida isolates were sensitive to amphotericin B, itraconazole, voriconazole, and caspofungin whereas fluconazole resistance was observed in 6.3% (MIC ≥ 64 μg/mL) of C. albicans and 6.6% of C. glabrata (MIC ≥ 64 μg/mL). The susceptible- dose-dependent rate was found in 10.5% of C. albicans. The P_rz values of C. albicans ranged from 0.37 to 0.66 for the DM and 0.44-0.73 for the non-DM group (P < 0.05). The non-albicans Candida (NAC) species produced higher degree of biomass and metabolic activity compared to C. albicans (P < 0.05). Furthermore, significant (p < 0.05) correlations were detected between the biofilm formation with P_rz values and fluconazole MICs. The most detected virulence factors were ALS3 and Sap5.

CONCLUSIONS

These results showed the importance of prevalence of NAC species in hemodialysis patients. Investigating antifungal susceptibility profile made a better understanding of the role of virulence markers in the pathogenesis of Candida strains.

Assessing pH-dependent activities of virulence factors secreted by Candida albicans

Candida albicans is an opportunistic pathogen that can thrive under adverse conditions including suboptimal pH, nutrient scarcity, and low levels of oxygen. Its pathogenicity is associated with the production of virulence factors such as extracellular hydrolytic enzymes and toxins. This study was aimed at determining the effect of external pH, substrate nature, and strain origin on protease, lipase, and hemolysin production. To achieve this objective, agar plate assays were performed at pH 5.0, 6.5, and 7.5 with substrates suitable for the detection of each family of enzymes. Moreover, the study was conducted with 20 clinical C. albicans isolates from blood, oral cavity, skin, urine, and vagina. The hydrolytic zones formed around the colonies were further measured to calculate the Ez (enzymatic zone) indexes. We found that detection of proteases in skim milk agar plates was possible for most isolates only at pH 5 (80%) and pH 6.5 (75%), whereas BSA plates could confer protease detection exclusively at pH 5 (80%). Similarly, the percentage of isolates possessing lipolytic activities was higher at pH 5 (90%) than at pH 6.5 (70%) and pH 7.5 (35%). In contrast, hemolytic activities were detected in all isolates at pH 6.5 and 7.5 but not at pH 5. Further analysis revealed that some differences in the detected activities could potentially be attributed to the anatomical origin of these isolates. Collectively, these findings suggest that the pH of the site of infection might be critical for mimicking the microenvironment employed to experimentally discover the key virulence factors.

A Reciprocal Link between Oral, Gut Microbiota during Periodontitis: The Potential Role of Probiotics in Reducing Dysbiosis-Induced Inflammation

Human body is colonized by a florid microbial community of bacteria, archaea, fungi, protists, helminths, and viruses, known as microbiota, which co-evolves with the host and influences its health through all stages of its life. It is well known that oral microorganisms form highly structurally and functionally organized multi-species biofilms and establish a network of complex mutual inter-species interactions having a primary function in synergy, signaling, or antagonism. This ecological model allows the microorganisms to increase their resistance to antimicrobial agents and settle a balanced microbes-host symbiotic relationship that ensures oral and global health status in humans. The host-associated microbiome is an important factor in human health and disease. Therefore, to develop novel diagnostic, therapeutic, and preventive strategies, microbiome's functions and the reciprocal interactions every microbiome entertains with other microbial communities in the human body are being investigated. This review provides an analysis of the literature about the close connection between the two largest microbial communities in humans: the oral and the gut microbiomes. Furthermore, it focuses on how the alteration of their microbial and functional characteristics can lead to and reciprocally influence the onset of both oral and intestinal microbiome-associated illness, along with the potential role of probiotics in ameliorating inflammation and microbial dysbiosis.

New Approach to Addison Disease: Oral Manifestations Due to Endocrine Dysfunction and Comorbidity Burden

This review highlights oral anomalies with major clinical impact in Addison disease (AD), including dental health and dermatologic features, through a dual perspective: pigmentation issues and AD comorbidities with oral manifestations. Affecting 92% of AD patients, cutaneomucosal hyperpigmentation is synchronous with or precedes general manifestations by up to a decade, underlying melanocytic infiltration of the basal epidermal layer; melanophages in the superficial dermis; and, rarely, acanthosis, perivascular lymphocytic infiltrate, and hyperkeratosis. Intraoral pigmentation might be the only sign of AD; thus, early recognition is mandatory, and biopsy is helpful in selected cases. The buccal area is the most affected location; other sites are palatine arches, lips, gums, and tongue. Pigmented oral lesions are patchy or diffuse; mostly asymptomatic; and occasionally accompanied by pain, itchiness, and burn-like lesions. Pigmented lingual patches are isolated or multiple, located on dorsal and lateral areas; fungiform pigmented papillae are also reported in AD individuals. Dermoscopy examination is particularly indicated for fungal etiology; yet, it is not routinely performed. AD’s comorbidity burden includes the cluster of autoimmune polyglandular syndrome (APS) type 1 underlying AIRE gene malfunction. Chronic cutaneomucosal candidiasis (CMC), including oral CMC, represents the first sign of APS1 in 70–80% of cases, displaying autoantibodies against interleukin (IL)-17A, IL-17F ± IL-22, and probably a high mucosal concentration of interferon (IFN)-γ. CMC is prone to systemic candidiasis, representing a procarcinogenic status due to Th17 cell anomalies. In APS1, the first cause of mortality is infections (24%), followed by oral and esophageal cancers (15%). Autoimmune hypoparathyroidism (HyP) is the earliest endocrine element in APS1; a combination of CMC by the age of 5 years and dental enamel hypoplasia (the most frequent dental complication of pediatric HyP) by the age of 15 is an indication for HyP assessment. Children with HyP might experience short dental roots, enamel opacities, hypodontia, and eruption dysfunctions. Copresence of APS-related type 1 diabetes mellitus (DM) enhances the risk of CMC, as well as periodontal disease (PD). Anemia-related mucosal pallor is related to DM, hypothyroidism, hypogonadism, corresponding gastroenterological diseases (Crohn’s disease also presents oral ulceration (OU), mucogingivitis, and a 2–3 times higher risk of PD; Biermer anemia might cause hyperpigmentation by itself), and rheumatologic diseases (lupus induces OU, honeycomb plaques, keratotic plaques, angular cheilitis, buccal petechial lesions, and PD). In more than half of the patients, associated vitiligo involves depigmentation of oral mucosa at different levels (palatal, gingival, alveolar, buccal mucosa, and lips). Celiac disease may manifest xerostomia, dry lips, OU, sialadenitis, recurrent aphthous stomatitis and dental enamel defects in children, a higher prevalence of caries and dentin sensitivity, and gingival bleeding. Oral pigmented lesions might provide a useful index of suspicion for AD in apparently healthy individuals, and thus an adrenocorticotropic hormone (ACTH) stimulation is useful. The spectrum of autoimmune AD comorbidities massively complicates the overall picture of oral manifestations.

Therapeutic Screening of Herbal Remedies for the Management of Diabetes

The study of diabetes mellitus (DM) patterns illustrates increasingly important facts. Most importantly, they include oxidative stress, inflammation, and cellular death. Up to now, there is a shortage of drug therapies for DM, and the discovery and the development of novel therapeutics for this disease are crucial. Medicinal plants are being used more and more as an alternative and natural cure for the disease. Consequently, the objective of this review was to examine the latest results on the effectiveness and protection of natural plants in the management of DM as adjuvant drugs for diabetes and its complex concomitant diseases.