Assessment of species distribution and virulence factors of oral fungal carriage among hospitalized patients with COVID-19: a case-control study

Background

The COVID-19 pandemic highlighted the need to study oral fungal carriage and its potential impact. In oral fungal environments, factors like changes in respiratory epithelium, increased pathogen attachment, local inflammation, and virulence factors could influence COVID-19 severity. The authors conducted a study to explore oral fungal carriage in COVID-19 patients and compare it to a healthy control group.

Methods

The authors executed a case-control investigation including 144 COVID-19 patients and an equivalent number of 144 healthy controls. The matching criteria encompassed age, sex, body mass index, and the history of antibiotic and antiviral medication intake. This research was performed over a span of 12 months from May 2021 to May 2022. The mouth area was sampled with a cotton-tipped swab. Subsequently, all the samples underwent fungal culture and PCR-sequencing procedures.

Results

In COVID-19 patients, oral fungal carriage was three times higher compared to healthy controls. Candida was the exclusive genus found in both groups, with Candida albicans being the most frequently isolated species (90.79%). Among COVID-19 patients, Candida species showed significantly higher esterase, proteinase, and hemolysin activity compared to healthy individuals. Both groups exhibited elevated levels of C. albicans virulence factors compared to non-albicans species.

Conclusions

It is crucial to understand the way that virulence factors of oral fungal carriage act in COVID-19 patients in order to come up with novel antifungal medications, identify the contributing factors to drug resistance, and manage clinical outcomes.

Effect of the 1064 nm Nd: YAG Laser on the MICs of Antifungals Used in Clinical Practice for the Treatment of Fungal Nail Infections

Introduction: The fungal nail infection (onychomycosis) involves 18%-40% of all nail disorders, which, although not fatal, can cause mechanical, aesthetic, occupational, and economic problems. Drug treatments due to prolonged treatment periods, drug interactions, adverse effects, and slow progression may associate with numerous negative outcomes. This study aimed to evaluate the long-pulsed 1064-nm Nd: YAG laser effect on fungal colonies and subsequently possible change in the minimum inhibitory concentrations (MICs) of common antifungals compared with the same non-lasered colonies as a novel way to investigate laser and antifungal interaction. Methods: Sixty onychomycosis samples consisting of saprophyte (n=20), dermatophyte (n=20), and yeast (n=20) duplicate colonies were isolated. A series was treated by a long-pulsed 1064-nm Nd: YAG laser. Afterward, the MIC (CLSI-M38-A2 and CLSI-M27-A3) of two series against common antifungals were compared. Results: After 1064-nm Nd: YAG laser irradiation in all 20 tested saprophytes, the MICs of terbinafine (P value<0.035) were changed, and in all 20 tested dermatophytes, the MICs of voriconazole (P value<0.021) were changed. Also, in all 20 tested yeasts, the MICs of caspofungin (P value<0.037) were changed. Moreover, in saprophytes, dermatophytes, and yeasts, significant changes in the MICs of itraconazole (P value<0.032), terbinafine (P value<0.025), and caspofungin (P value<0.037) were detected. Our result showed the GM MICs of the 1064-nm Nd: YAG laser in all saprophyte, dermatophyte, and yeast groups were lower than in the control group. Conclusion: The present study indicated that the long-pulsed 1064-nm Nd: YAG laser significantly changes the MICs of antifungals in onychomycosis clinical samples.

Design of a multi-epitopic vaccine against Epstein-Barr virus via computer-based methods

Background

Scientific findings have shown that Epstein-Barr virus (EBV) plays a key role in the development of some tumor diseases. Therefore, this study intends to take a practical step in controlling the pathogenicity of this virus by designing an effective vaccine based on the virus Capsid Envelope and Epstein–Barr nuclear immunogen (EBNA) Proteins Epitopes. Currently, there are no effective drugs or vaccines to treat or prevent EBV infection. So, we applied a computer-based strategy to design an epitope vaccine

Results

We designed a powerful multi-epitope peptide vaccine against EBV using in silico analysis. The vaccine is made up of 844 amino acids derived from three different types of proteins (Envelope, Capsid, EBNA) found in two different viral strains. responses. These epitopes have a high immunogenic capacity and are not likely to cause allergies. To enhance the vaccine immunogenicity, we used rOv-ASP-1, a recombinant Onchocerca volvulus activation associated protein-1, as an adjuvant and linked it to the vaccine’s N and C terminus. The physicochemical and immunological properties of the vaccine structure were evaluated. The proposed vaccine was stable, with a stability index of 33.57 and a pI of 10.10, according to bioinformatic predictions. Docking analysis revealed that the vaccine protein binds correctly with immunological receptors.

Conclusion

Our results demonstrated that the multi-epitope vaccine might be potentially immunogenic and induce humoral and cellular immune responses against EBV. This vaccine can interact appropriately with immunological receptors Also, it has a high-quality structure and suitable characteristics such as high stability.

Drug Resistance and Biofilm Formation in Candida Species of Vaginal Origin

BACKGROUND

Candida species are normal vaginal flora in healthy women, which can cause vulvovaginal candid-iasis (VVC). The formation of biofilm is a cause of drug resistance in Candida species of vaginal origin. We aimed to specify Candida species cause VVC, detect their biofilm-forming ability, and antifungal susceptibility pattern.

METHODS

Overall 150 vaginal samples were collected from suspected cases of referring to Bahar Hospital of Shahroud, Iran between Jan 2018 and Jan 2019. Samples were cultured on Sabouraud dextrose agar (SDA), Chrome gar Candida and Corn meal agar (CMA). PCR-RFLP was performed to confirm the identification. Bio-film formation of the identified species was measured by the Crystal Violet method. The susceptibility to fluconazole, clotrimazole, and miconazole was determined based on the CLSI document M27-A3.

RESULTS

Of 50 women (33.3%) were suffering from VVC. C.albicans was the predominant species isolated in this study (n=39, 78%) followed by C. glabratia (n=11, 22%). In addition, in 25 (50%) of positive samples, bio-film formation was determined. The mean MIC of fluconazole and clotrimazole for C. albicans was 5.02 μg/mL and 3.92 μg/mL, respectively. Furthermore, the mean MIC related to these drugs for C. glabrata was 12.45 μg / mL and 4.1μg / mL, respectively. The mean diameter of miconazole inhibition zone for C. albicans and C. glabra isolates was 25.13 mm and 24.5mm, respectively and all of them were susceptible to this drug.

CONCLUSION

C.albicans was the predominant Candida species isolated from patients with VVC and also was the predominant biofilm producer species.

Fungal and bacterial co-infections of the respiratory tract among patients with COVID-19 hospitalized in intensive care units

Backgrounds

The pandemic of COVID-19 has created a global public health crisis. ICU patients with COVID-19 are prone to infections of bacterial and/or fungal origins due to several risk factors. Consequently, the current study was conducted to evaluate the frequency, demographic characteristics, underlying conditions, and etiologic agents of fungal and bacterial co-infections of the respiratory tract among ICU patients with COVID-19 in Iran.

Materials and methods

From May to October 2020, sputa and endotracheal aspirates were collected from ICU patients hospitalized with COVID-19 who also were suspected of bacterial and/or fungal co-infections according to inclusion criteria. The etiologic agents of bacterial co-infections were identified using the Vitek 2 identification method. For fungal identification, all samples were analyzed by direct microscopy using KOH 10% and culture. Furthermore, all isolates were subjected to sequencing method.

Results

A total of 73 lung specimens were obtained from patients who met the inclusion criteria. Of these, in 15 cases (20.54%) fungal and/or bacterial co-infections were confirmed. Males were more infected (73.33%) and all of them were between 49 and 79 years. Candida albicans (n = 8, 61.53%) and Klebsiella pneumoniae (n = 5, 38.46%) were the most frequent etiologic agents related to fungal and bacterial co-infections, respectively. Pneumonia (n = 15, 100%) and diabetes mellitus (n = 8, 53.33%) were documented as the most prevalent underlying conditions. In the current study, 3 out of 15 patients (20%) died.

Conclusion

The frequency of bacterial co-infections of the respiratory tract in ICU patients hospitalized with COVID-19 was relatively high. According to the results, one of the causes of death of these patients could be a secondary infection.

Epidemiology, risk factors, species distribution, and antifungal susceptibility of candidemia among hospitalized patients with COVID-19

Background and Purpose:

The pandemic of COVID-19 has caused a worldwide health crisis. Candidemia is a potentially lethal condition that has not yet been enough discussed in patients with COVID‐19. The current study aimed to investigate the prevalence of candidemia among Iranian COVID‐19 patients and characterize its causative agents and the antifungal susceptibility pattern

Materials and Methods:

The present cross-sectional survey was carried out from March 2020 to March 2021 at Imam Khomeini Hospital, Tehran, Iran. Blood specimens were obtained from patients with confirmed coronavirus infection who also had criteria for candidemia and were examined for any Candida species by conventional and molecular techniques. Susceptibility of isolates to amphotericin B, voriconazole, itraconazole, fluconazole, caspofungin, and 5-flucytosine was tested using the CLSI broth dilution technique.

Results:

In total, 153 patients with COVID-19 were included and candidemia was confirmed in 12 (7.8 %) of them. The majority of patients were ≥ 50 years of age (n=9) and female (n=8). Moreover, 6 out of the 12 patients were diabetic. The presence of central venous catheters, broad-spectrum antibiotic therapy, ICU admission, and mechanical ventilation was observed in all patients. The C. albicans (n=7, 58.3 %) and C. dubliniensis (n=2, 16.7%) were the most common isolated species. Amphotericin B and 5-flucytosine were the most active drugs. Despite antifungal treatment, 4 out of 12 patients (33.3 %) died.

Conclusion:

Due to the high mortality, the early diagnosis and proper treatment of candidemia are essential requirements for optimal clinical outcomes in COVID-19 patients.

The Prevalence, Etiological Agents, Clinical Features, Treatment, and Diagnosis of HIV-Associated Oral Candidiasis in Pediatrics Across the World: A Systematic Review and Meta-Analysis

In HIV-infected pediatrics, oral candidiasis (OC) is a global issue of concern due to its association with dysphagia, malnutrition, and mortality. The present systematic review and meta-analysis are the first to determine the prevalence of OC in HIV-infected pediatrics worldwide. We searched international (PubMed, Web of Science, Scopus, and Embase) databases for studies published between January 2000 to May 2020 reporting the epidemiologic features of OC in HIV-infected pediatrics. Inclusion and exclusion criteria were defined to select eligible studies. Data were extracted and presented according to PRISMA guidelines. The results of the meta-analysis were visualized as a forest plot. Heterogeneity was also analyzed using the I ², and τ² statistics. The publication bias was evaluated using Egger test. The literature search revealed 1926 studies, of which 34 studies met the eligibility criteria, consisting of 4,474 HIV-infected pediatrics from 12 different countries. The overall prevalence of OC among HIV-infected pediatrics was 23.9% (95% CI 17.3-32.0%), and Candida albicans was the most prevalent etiologic agent. Pseudomembranous candidiasis was the predominant clinical manifestation in HIV-infected pediatrics suffering from OC. Thirty articles involving 4,051 individuals provided data on HIV treatment status. Among the 4,051 individuals, 468 (11.53%) did not receive HIV treatment. The data from 11 articles demonstrated that HIV treatment was significantly associated with a reduction in oral Candida colonization or infection. In contrast, others showed the opposite relationship or did not report any statistical data. A high level of I ² (I ² = 96%, P < 0.01) and τ² (τ² = 1.36, P < 0.01) was obtained among studies, which provides evidence of notable heterogeneity between studies. OC is approximately frequent in HIV-positive children. Therefore, efforts should be made to teach dental and non-dental clinicians who care for HIV-infected pediatrics to diagnose and treat this infection.