Molecular identification and antifungal susceptibility profiles of etiologic agents of oral candidiasis among HIV-positive patients: A multicenter study

Background and Purpose

Human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) is a serious risk factor for oral candidiasis (OC). In this regard, the present study aimed to investigate the frequency of Candida species collected from the oropharyngeal cavity of HIV-positive patients and the sensitivity of these isolates to antifungal drugs.

Materials and Methods

Oral samples were collected from 169 HIV-positive patients. In addition to culture-based methods, a molecular assay via the polymerase chain reaction-restriction fragment length polymorphism method was applied to identify isolates using the MspI restriction enzyme. The disk diffusion method determined the susceptibility of isolated yeasts to common antifungal drugs according to the CLSI M44-A2 protocol.

Results

In total, 81 participants (47.92%) were positive for OC, and Candida albicans was the most prevalent yeast (53.98%). The median age of patients was 36 years old (IQR=10.5; 17-59), and it was found that women are 27% more susceptible to HIV-associated OC (OR=1.268; 95% CI: 0.685-2.348). Patients who received antifungal therapy had a 97.3% reduced chance for OC (OR: 0.027; 95% CI: 0.008-0.091; P-value: 0.000). Antifungal therapy reduced the risk of OC by 97.3% (OR=0.027; 95% CI=0.008-0.091; P=0.000), and antiretroviral therapy decreased the chance of OC 4.42 times (OR=4.423; 95% CI=1.697-11.528; P=0.002). The resistance rates for antifungals, namely fluconazole, ketoconazole, itraconazole, amphotericin B, and nystatin were 15.93%, 8.85%, 7.96%, 5.31%, and 4.42%, respectively.

Conclusion

Although several decades have passed since the emergence of HIV/AIDS, little information is available about fungal colonization and infections in this population. Further investigations are suggested using novel and reference molecular identification methods, such as matrix-assisted laser desorption ionization time-of-flight mass spectrometry and sequencing, respectively. In addition, more reliable methods for antifungal susceptibility testing are recommended.

Diagnosis of Oral candidiasis in Patients under 12 Years: 18S rRNA as a Marker of Molecular Characterization of Candida tropicalis

Candida tropical has been found as the most abundant pathogenic yeast species under the group Candida-non-albicans. Despite this, it is taxonomically related to C. albicans and has many of its pathogenic characteristics. Infection with Candida tropicalis is closely associated with many virulence factors encoded by multiple virulence genes. This study aims to diagnose C. tropicalis based on the presence of 18SrRNA and to detect many virulence genes. C. tropicalis isolates were collected from oral candidiasis patients. Children infected with oral thrush ranging in age from infants to 12 years old provided 150 samples. C. albicans (66.68 %), C. tropicalis (13.21 %), C. krusie (9.43 %), C. parapsilosis (7.55 %), and C. glarata were isolated as C. tropicalis types, according to the findings of the present study (2.83%). The presence of the 18SrRNA gene was confirmed in the isolates. All isolates were positive for cph1 and hwp1, while some were positive for sap1 (78.5%) and plb1 genes (71.4%). Using sequences and phylogenetic trees, it was determined that there was negligible genetic variation between local isolates and global strains. These virulence factor genes play a crucial role in developing infections.

A comparative study on the production of extracellular hydrolytic enzymes of C. albicans and non-albicans Candida species isolated from HIV+/AIDS patients and healthy individuals

Background and Purpose

Oropharyngeal candidiasis is the most prevalent opportunistic fungal infection in patients with human immunodeficiency virus (HIV) as well as other immunodeficiency disorders, which is caused by various Candida species, mostly Candida albicans. Studies have shown that Candida isolates differ in their pathogenicity. These variations are attributed to virulence factors, host characteristics, and the target tissue. This study aimed to determine and compare the secretion of hydrolytic enzymes in C. albicans and non-albicans Candida species isolated from HIV⁺/AIDS patients and healthy individuals.

Materials and Methods

Samples were taken from 201 patients with HIV and 118 healthy individuals. The samples were identified by macroscopic, phenotypic, and molecular methods, and virulence factors were subsequently measured. Statistical differences in enzymatic activity of various Candida isolates were calculated (P<0.0001).

Results

In total, 95 samples (47.20%) from patients and 46 samples (38.90%) from healthy individuals were positive for the growth of different Candida species. There were 39 (41.10%) and 36 (78.30%) C. albicans in patients and healthy individuals, respectively, as well as 56 (58.90%) and 10 (21.70%) non-albicans species in patients and healthy subjects, respectively. All the enzymes produced by Candida species enzymes were at low, medium, and high levels. Hemolysin activity in Candida species isolated from patients was significantly higher, compared to healthy individuals. Moreover, the activity of all C. albicans enzymes in patients was significantly higher than other Candida species.

Conclusion

The C. albicans isolated from HIV-positive individuals secreted higher amounts of exoenzymes, and can cause oropharyngeal candidiasis and become a source of candidiasis for the host.

Comparison of antifungal efficacy of ethanolic extracts of Woodfordia fruticosa leaf and Punica granatum peel in uncontrolled diabetic patients wearing removable dentures: A randomized controlled clinical trial

BACKGROUND AND PURPOSE

The search for the development of a suitable novel antimicrobial agent for fungal diseases continues to be a key problem in the current clinical field. The present investigation was aimed to determine the antifungal effect of the ethanolic crude extracts of Woodfordia fruticosa leaf (Wfl) and Punica granatum peel (Pgp) in uncontrolled diabetic patients wearing removable dentures.

MATERIALS AND METHODS

The ethanolic extracts of both plants were prepared using the soxhlet extraction method, and the obtained metabolites were confirmed by thin- layer chromatography. After the preparation of the mouthwash, a total of 100 subjects were randomly divided into two groups. Each subject was given physiological saline at the baseline. Group I was provided with P. granatum mouthwash, while Group II was given W. fruticosa mouthwash. Following the administration of the mouthwash, the patients were requested to rinse the mouthwash using the oral rinse technique twice daily 5 ml/rinse for 30 sec. Subsequently, colony-forming units (CFU) were evaluated in the participants. Post-therapeutic samples were collected 1 h and 1 week after the mouthwash use.

RESULTS

The mean reduction of CFU was calculated at the baseline, as well as 1 h and 1 week after using mouthwash. The results indicated a drastic reduction in CFU 1 h and 1 week after the application of Wfl mouthwash.

CONCLUSION

The obtained data revealed that Wfl had potential anticandidal activity against Candida yeast cells, probably owing to its bioactive compounds like glycosides. Therefore, this agent can be used effectively as a natural remedy for the treatment of oral candidiasis. However, the exact mechanism of action of this plant needs to be elucidated.