Candida parapsilosis, an emerging fungal pathogen

Congenital Sepsis with Candida albicans-A Rare Event in the Neonatal Period: Report of Two Cases and Literature Review

Candida spp. is rarely found in neonatal early-onset sepsis (EOS) etiology. However, candidemia is associated with increased mortality and morbidity, as in late-onset sepsis. Congenital candidiasis may present as a mucocutaneous infection or, more rarely, as a systemic infection in term and preterm infants. This paper presents case reports of two cases of congenital systemic candidiasis (CSC) caused by Candida albicans and a review of the data in the literature. An electronic search of PubMed, Scopus, and Google Scholar was performed to identify publications on congenital candidiasis. Both neonates were male, born vaginally, with risk factors for congenital candidiasis. One of the infants was born at term and presented with an almost generalized maculopapular rash at birth and congenital candidemia; parenteral fluconazole was used successfully. The other infant was born prematurely at 28 weeks of gestation; blood culture, gastric aspirate, and maternal vaginal cultures sampled at birth were positive for C. albicans. Liver and kidney involvement became apparent on the third day of life, while lung involvement was clinically evident on the fourth day. Prolonged parenteral fluconazole was administered due to multiple organ involvement and persistent candidemia. Our experience with the presented cases, similar to data in the literature, suggests that CSC may occur at any gestational age, with various clinical pictures, sometimes mimicking bacterial sepsis, and even in the absence of the rash. Careful anamnesis and a high index of suspicion are important for the prompt recognition and treatment of CSC, optimizing the short- and long-term outcomes. Further research should focus on CSC to improve its diagnosis.

Understanding the role of bats as fungal vectors in the environment

Bats (Chiroptera), the second largest group of mammals, are known for their unique immune system and their ability to act as vectors for various zoonoses. Bats also act as important carriers of fungi, which include plant, animal, and human pathogens. Their roosting areas, foraging behaviors, and even migration routes make bats ideal vectors for fungi. We isolated 75 culturable fungal species from bats in Yunnan Province, China, with 36 species representing known pathogens of plants, animals, and humans, while 39 species are non-pathogenic fungi. Among these species, 77% (58 species) belonged to Ascomycota, 9% (seven species) belonged to Basidiomycota, and 13% (10 species) belonged to Mucoromycota. Even though several taxonomic studies on fungi associated with bats have been published, studies exploring the role of bats as fungal vectors are lacking. This study discusses the fungi host-specific traits and pathogenicity and the impact and ecological significance of bats as fungal vectors.

Prosthetic Joint Infections due to Candida Species: A Multicenter International Study

BACKGROUND

Prosthetic joint infection (PJI) caused by Candida spp is a severe complication of arthroplasty. We investigated the outcomes of Candida PJI.

METHODS

This was a retrospective observational multinational study including patients diagnosed with Candida-related PJI between 2010 and 2021. Treatment outcome was assessed at 2-year follow-up.

RESULTS

A total of 269 patients were analyzed. Median age was 73.0 (interquartile range [IQR], 64.0-79.0) years; 46.5% of patients were male and 10.8% were immunosuppressed. Main infection sites were hip (53.0%) and knee (43.1%), and 33.8% patients had fistulas. Surgical procedures included debridement, antibiotics, and implant retention (DAIR) (35.7%), 1-stage exchange (28.3%), and 2-stage exchange (29.0%). Candida spp identified were Candida albicans (55.8%), Candida parapsilosis (29.4%), Candida glabrata (7.8%), and Candida tropicalis (5.6%). Coinfection with bacteria was found in 51.3% of cases. The primary antifungal agents prescribed were azoles (75.8%) and echinocandins (30.9%), administered for a median of 92.0 (IQR, 54.5-181.3) days. Cure was observed in 156 of 269 (58.0%) cases. Treatment failure was associated with age >70 years (OR, 1.811 [95% confidence interval {CI}: 1.079-3.072]), and the use of DAIR (OR, 1.946 [95% CI: 1.157-3.285]). Candida parapsilosis infection was associated with better outcome (OR, 0.546 [95% CI: .305-.958]). Cure rates were significantly different between DAIR versus 1-stage exchange (46.9% vs 67.1%, P = .008) and DAIR versus 2-stage exchange (46.9% vs 69.2%, P = .003), but there was no difference comparing 1- to 2-stage exchanges (P = .777).

CONCLUSIONS

Candida PJI prognosis seems poor, with high rate of failure, which does not appear to be linked to immunosuppression, use of azoles, or treatment duration.

Evaluating and Managing the Microbial Contamination of Eye Drops: A Two-Phase Hospital-Based Study

The microbial contamination of eye drop tips and caps varies between 7.7% and 100%. In seeking patient protection and continuous improvement, the Pharmacy Department in the Sterile Ophthalmological and Oncological Preparations Unit at Cochin Hospital AP-HP, Paris, France, conducted a two-phase study to compare the antimicrobial efficiency and practical use of standard packaging and a marketed eye drop container incorporating a self-decontaminating antimicrobial green technology by Pylote SAS at the tip and cap sites. The first phase was conducted in situ to identify the microbial contaminants of eye drops used in the hospital and community settings. A total of 110 eye drops were included for testing. Staphylococcus species were the most prevalent bacteria. Candida parapsilosis was detected in only one residual content sample and, at the same time, on the cap and tip. The second phase was performed in vitro, according to JIS Z2801. Reductions above one log in Staphylococcus aureus and Pseudomonas aeruginosa counts were noted in Pylote SAS eye drop packaging after 24 h of contact. The practical tests showed satisfactory results. Pylote SAS antimicrobial mineral oxide technology exhibited promising effects that combined effectiveness, safety, and sustainability to protect the patient by preventing infections due to the contamination of eye drop containers.

Comparative Evaluation of Candida Species-Specific T-Cell Immune Response in Human Peripheral Blood Mononuclear Cells

Non-albicans Candida (NAC) species are increasingly recognized as significant contributors to candidemia infections; however, relatively less is known about the immune responses induced by these species. In this study, we compared the cytokine production ability of human peripheral blood mononuclear cells (PBMCs) upon stimulation with different Candida species (Candida spp.). We measured secreted cytokines using ELISA and checked the functional profiles of T-cell responses using multicolor flow cytometry. Although there was a differential expression of cytokines against Candida spp., significant difference were observed in the levels of IFN-γ, TNF-α, IL-10, IL-12p40, and IL-23 (p < 0.05) between Candida spp. A significant difference was observed between C. albicans and C. glabrata (p = 0.026) in the levels of TNF-α. C. glabrata showed significant differences compared to C. albicans, C. parapsilosis, and C. krusei in the levels of IL-10 (p values of 0.02, 0.04, and 0.01, respectively). Despite the percentages of CD4+ and CD8+ expressing Th1, Th2, and Th17 cytokines being higher in stimulated PBMCs, none of the Candida spp. showed significant differences. The levels of secreted IL-17A and IL-23 were consistently lower in Candida spp. regardless of the stimulus used. Here, we showed the differential regulation of Th1, Th2, and Th17 during Candida spp. stimulation of the immune system ex vivo. Additionally, our findings suggest that C. albicans elicits an IFN-γ response, whereas C. glabrata promotes IL-10 cellular responses, but this warrants additional studies to conclude this association. This investigation holds the potential to advance our comprehension of the distinct immune responses induced by Candida spp., with probable implications in designing antifungal immunotherapeutics.

Candida parapsilosis: Heterogeneous and strain-specific expression of secreted aspartic proteases (Sapp1 and Sapp2)

The increasing prevalence of Candida parapsilosis as a causative agent of fungal infections underscores the need to comprehensively understand its virulence factors. Secreted aspartic proteases (Saps) play a significant role in adhesion events, promoting biofilm formation, causing tissue damage and evading the host's immune response. In C. parapsilosis, three Saps have been identified: Sapp1, Sapp2 and Sapp3. The present study investigates the production dynamics of Sapp1 and Sapp2 across 10 clinical isolates of C. parapsilosis using various approaches. Each fungal isolate demonstrated the capability to utilize bovine serum albumin (BSA) as the sole nitrogen source, as evidenced by its degradation in a cell-free culture medium, forming low molecular mass polypeptides. Interestingly, the degradation of different proteinaceous substrates, such as BSA, human serum albumin (HSA), gelatin and hemoglobin, was typically isolate-dependent. Notably, higher proteolysis of HSA compared to BSA, gelatin and hemoglobin was observed. A quantitative assay revealed that the cleavage of a peptide fluorogenic substrate (cathepsin D) was isolate-specific, ranging from 44.15 to 270.61 fluorescence arbitrary units (FAU), with a mean proteolysis of 150.7 FAU. The presence of both Sapp1 and Sapp2 antigens on the cell surface of these fungal isolates was confirmed through immunological detection employing specific anti-Sapp1 and anti-Sapp2 antibodies. The surface levels of Sapp1 were consistently higher, up to fourfold, compared to Sapp2. Similarly, higher levels of Sapp1 than Sapp2 were detected in fungal secretions. This study provides insights into the dynamic expression and regulation of Sapps in C. parapsilosis, highlighting a known virulence factor that is considered a potential target for drug development against this increasingly prominent pathogen.

Genotypic and phenotypic characteristics of Candida parapsilosis bloodstream isolates: Health Care Associated Infections in a teaching Hospital in Italy

BACKGROUND

Candidemia is the most common healthcare associated invasive fungal infection. Over the last few decades, candidemia caused by Candida species other than Candida albicans, particularly the Candida parapsilosis complex, has emerged worldwide. The aims of this study were: to analyze the genotypic and phenotypic characteristics of C. parapsilosis strains isolated from blood cultures and the environment in a hospital in southern Italy, to study the possible source of infection and to correlate the isolated strains.

METHODS

From April to October 2022, cases of candidemia due to C. parapsilosis in patients admitted to a hospital in the Apulia region were investigated. However, 119 environmental samples from the intensive care unit were collected for identification of the likely environmental reservoir of infection. Routine antifungal (amphotericin B, anidulafungin, fluconazole) susceptibility was performed on all isolates. Whole genome sequencing was performed to study the genotypic correlation of the isolates. Biofilm biomass and metabolic activity were also quantified for all isolates.

RESULTS

A total of 43 C. parapsilosis isolates were cultured from the bloodstream of each patient in different departments, and seven surface samples were positive for C. parapsilosis. Most of the isolated yeasts (41/50; 85 %) were resistant to fluconazole and were genetically related to each other, suggesting an ongoing clonal outbreak of this pathogen. The fluconazole-susceptible isolates produced significantly more biofilm than did the resistant isolates. Metabolic activity was also higher for fluconazole-susceptible than resistant isolates.

CONCLUSION

Cross-transmission of the microorganisms is suggested by the phenotypic similarity and genetic correlation between clinical and environmental strains observed in our study.

Molecular and Epidemiological Investigation of Fluconazole-resistant Candida parapsilosis-Georgia, United States, 2021

Background

Reports of fluconazole-resistant Candida parapsilosis bloodstream infections are increasing. We describe a cluster of fluconazole-resistant C parapsilosis bloodstream infections identified in 2021 on routine surveillance by the Georgia Emerging Infections Program in conjunction with the Centers for Disease Control and Prevention.

Methods

Whole-genome sequencing was used to analyze C parapsilosis bloodstream infections isolates. Epidemiological data were obtained from medical records. A social network analysis was conducted using Georgia Hospital Discharge Data.

Results

Twenty fluconazole-resistant isolates were identified in 2021, representing the largest proportion (34%) of fluconazole-resistant C parapsilosis bloodstream infections identified in Georgia since surveillance began in 2008. All resistant isolates were closely genetically related and contained the Y132F mutation in the ERG11 gene. Patients with fluconazole-resistant isolates were more likely to have resided at long-term acute care hospitals compared with patients with susceptible isolates (P = .01). There was a trend toward increased mechanical ventilation and prior azole use in patients with fluconazole-resistant isolates. Social network analysis revealed that patients with fluconazole-resistant isolates interfaced with a distinct set of healthcare facilities centered around 2 long-term acute care hospitals compared with patients with susceptible isolates.

Conclusions

Whole-genome sequencing results showing that fluconazole-resistant C parapsilosis isolates from Georgia surveillance demonstrated low genetic diversity compared with susceptible isolates and their association with a facility network centered around 2 long-term acute care hospitals suggests clonal spread of fluconazole-resistant C parapsilosis. Further studies are needed to better understand the sudden emergence and transmission of fluconazole-resistant C parapsilosis.

Photoactivated riboflavin inhibits planktonic and biofilm growth of Candida albicans and non-albicans Candida species

Fungal infections caused by Candida species pose a serious threat to humankind. Antibiotics abuse and the ability of Candida species to form biofilm have escalated the emergence of drug resistance in clinical settings and hence, rendered it more difficult to treat Candida-related diseases. Lethal effects of Candida infection are often due to inefficacy of antimicrobial treatments and failure of host immune response to clear infections. Previous studies have shown that a combination of riboflavin with UVA (riboflavin/UVA) light demonstrate candidacidal activity albeit its mechanism of actions remain elusive. Thus, this study sought to investigate antifungal and antibiofilm properties by combining riboflavin with UVA against Candida albicans and non-albicans Candida species. The MIC20 for the fluconazole and riboflavin/UVA against the Candida species tested was within the range of 0.125-2 μg/mL while the SMIC50 was 32 μg/mL. Present findings indicate that the inhibitory activities exerted by riboflavin/UVA towards planktonic cells are slightly less effective as compared to controls. However, the efficacy of the combination towards Candida species biofilms showed otherwise. Inhibitory effects exerted by riboflavin/UVA towards most of the tested Candida species biofilms points towards a variation in mode of action that could make it an ideal alternative therapeutic for biofilm-related infections.

Ascomycetes yeasts: The hidden part of human microbiome

The fungal component of the microbiota, the mycobiota, has been neglected for a long time due to its poor richness compared to bacteria. Limitations in fungal detection and taxonomic identification arise from using metagenomic approaches, often borrowed from bacteriome analyses. However, the relatively recent discoveries of the ability of fungi to modulate the host immune response and their involvement in human diseases have made mycobiota a fundamental component of the microbial communities inhabiting the human host, deserving some consideration in host-microbe interaction studies and in metagenomics. Here, we reviewed recent data on the identification of yeasts of the Ascomycota phylum across human body districts, focusing on the most representative genera, that is, Saccharomyces and Candida. Then, we explored the key factors involved in shaping the human mycobiota across the lifespan, ranging from host genetics to environment, diet, and lifestyle habits. Finally, we discussed the strengths and weaknesses of culture-dependent and independent methods for mycobiota characterization. Overall, there is still room for some improvements, especially regarding fungal-specific methodological approaches and bioinformatics challenges, which are still critical steps in mycobiota analysis, and to advance our knowledge on the role of the gut mycobiota in human health and disease. This article is categorized under: Immune System Diseases > Genetics/Genomics/Epigenetics Immune System Diseases > Environmental Factors Infectious Diseases > Environmental Factors.

Antifungal drug resistance in Candida: a special emphasis on amphotericin B

Invasive fungal infections in humans caused by several Candida species, increased considerably in immunocompromised or critically ill patients, resulting in substantial morbidity and mortality. Candida albicans is the most prevalent species, although the frequency of these organisms varies greatly according to geographic region. Infections with C. albicans and non-albicans Candida species have become more common, especially in the past 20 years, as a result of aging, immunosuppressive medication use, endocrine disorders, malnourishment, extended use of medical equipment, and an increase in immunogenic diseases. Despite C. albicans being the species most frequently associated with human infections, C. glabrata, C. parapsilosis, C. tropicalis, and C. krusei also have been identified. Several antifungal drugs with different modes of action are approved for use in clinical settings to treat fungal infections. However, due to the common eukaryotic structure of humans and fungi, only a limited number of antifungal drugs are available for therapeutic use. Furthermore, drug resistance in Candida species has emerged as a result of the growing use of currently available antifungal drugs against fungal infections. Amphotericin B (AmB), a polyene class of antifungal drugs, is mainly used for the treatment of serious systemic fungal infections. AmB interacts with fungal plasma membrane ergosterol, triggering cellular ion leakage via pore formation, or extracting the ergosterol from the plasma membrane inducing cellular death. AmB resistance is primarily caused by changes in the content or structure of ergosterol. This review summarizes the antifungal drug resistance exhibited by Candida species, with a special focus on AmB.

Candida parapsilosis bone marrow infection in an immunocompetent patient

Background

We discuss a case of an immunocompetent patient who presented with fever and tachypnoea, found to have Candida parapsilosis bone marrow infection, cultured on bone marrow aspirate sample. Candida parapsilosis is an opportunistic yeast pathogen that typically affects immunocompromised individuals, or occurs in patients with apparent introduced source; neither of these factors were present for this case. Bone marrow aspirates and trephines are not regular investigations for fever; however they can be useful diagnostic aids as evidenced in this case.

Case report

An 83-year-old woman presenting with fevers and tachypnoea was being treated for a systemic bacterial infection, however was unresponsive to empirical antibiotic therapy. To exclude an occult malignancy, an 18-fluorodeoxyglucose positron emission tomography scan was conducted. Significant bone marrow uptake was noted, prompting a bone marrow aspirate and trephine to investigate for a hematological malignancy. While the trephine biopsy was benign, a culture of the aspirate grew Candida parapsilosis. Intravenous antifungal therapy was initiated; however, the patient did not improve despite targeted therapy likely due to delays in diagnosis, and was palliated.

Conclusion

Our case seeks to demonstrate a novel case whereby a bone marrow aspirate culture provided a conclusive diagnosis of invasive Candida parapsilosis bone marrow infection, and guided treatment in an immunocompetent patient. It is important for clinicians to consider invasive fungal infections in febrile patients regardless of immune status. Additionally, when performing a bone marrow aspirate and trephine on a febrile patient, we recommend including aspirate fungal cultures to investigate for an invasive fungal infection.

Isolated Cutaneous Granuloma Caused by Candida Parapsilosis: Case Report and Literature Review

Candidal granuloma is an uncommon type of deep chronic cutaneous candidiasis. Candida albican is the most common causative pathogen for candidal granuloma. We report herein the original case of a 69-year-old Chinese woman presented with a 3-year of painful cutaneous lesion on the back of left hand. Physical examination revealed a 4 × 5 cm large infiltrative reddish plaque with unclear boundaries. The yellow-white crusts were observed on the uneven surface of plaque. Histopathological examination of biopsy tissue revealed that yeast cells and the horizontal section of hyphae in the dermis by hematoxylin eosin staining and periodic acid-Schiff staining. Finally, the pathogen was identified as Candida parapsilosis by mycological examination and molecular identification. The patient was treated with itraconazole oral 200 mg twice daily combined with topical terbinafine hydrochloride cream for 2 months. The lesions were fully resolved and no recurrence was observed. Since the cutaneous infection caused by C. parasilosis were rarely reported, we also reviewed all 11 cases of cutaneous infection caused by C. parapsilosis in the PubMed. Our study highlighted that chronic unilateral infiltrated plaques or ulcers should be aware of the occurrence of fungal granuloma including candidal granuloma especially in immunocompromised patients.

Role of CARD9 in Cell- and Organ-Specific Immune Responses in Various Infections

The caspase recruitment domain-containing protein 9 (CARD9) is an intracellular adaptor protein that is abundantly expressed in cells of the myeloid lineage, such as neutrophils, macrophages, and dendritic cells. CARD9 plays a critical role in host immunity against infections caused by fungi, bacteria, and viruses. A CARD9 deficiency impairs the production of inflammatory cytokines and chemokines as well as migration and infiltration, thereby increasing susceptibility to infections. However, CARD9 signaling varies depending on the pathogen causing the infection. Furthermore, different studies have reported altered CARD9-mediated signaling even with the same pathogen. Therefore, this review focuses on and elucidates the current literature on varied CARD9 signaling in response to various infectious stimuli in humans and experimental mice models.

Fungal coexistence in the skin mycobiome: a study involving Malassezia, Candida, and Rhodotorula

Evidence of fungal coexistence in humans points towards fungal adaptation to the host environment, like the skin. The human commensal Malassezia has evolved, especially residing in sebum-rich areas of the mammalian body where it can get the necessary nutrition for its survival. This fungus is primarily responsible for skin diseases like Pityriasis versicolor (PV), characterized by hypo or hyperpigmented skin discoloration and erythematous macules. In this manuscript, we report a 19-year-old healthy female who presented with a one-year history of reddish, hypopigmented, asymptomatic lesions over the chest and a raised erythematous lesion over the face. Upon clinical observation, the patient displayed multiple erythematous macules and erythematous papules over the bilateral malar area of the face, along with multiple hypopigmented scaly macules present on the chest and back. Based on the above clinical findings, a diagnosis of PV and Acne vulgaris (AV) was made. Interestingly, the patient was immunocompetent and didn't have any comorbidities. Upon isolation of skin scrapings and post-culturing, we found the existence of three fungal genera in the same region of the patient's body. We further went on to confirm the identity of the particular species and found it to represent Malassezia, Rhodotorula, and Candida. We report how Malassezia, the predominant microbial resident skin fungus, coexists with other fungal members of the skin mycobiome. This study on an applied aspect of microbiology also shows how important it is to identify the fungal organism associated with skin infections so that appropriate therapeutics can be advised to avoid cases of relapse.

Unresolved issues in the diagnosis of catheter related candidemia: A position paper

The incidence and recent trends of candidemia and the contribution of the COVID-19 pandemic to its evolution are not well documented. The catheter is a major focus of Candida spp. infections, but the methods used to confirm the origin of candidemia are still based on the data generated for bacterial infection. The presence of Candida spp. on the tip of a removed catheter is the gold standard for confirmation but it is not always possible to remove it. Conservative methods, without catheter removal, have not been specifically studied for microorganisms whose times of growth are different from those of bacteria and therefore these results are not applicable to candidemia. The different Candida species do not have a particular tropism for catheter colonization and fungal biomarkers have not yet been able to contribute to the determination of the origin of candidemia. Techniques such Candida T2 Magnetic Resonance (T2MR) has not yet been applied for this purpose. Finally, there is not yet a consensus of how to proceed when Candida spp. is isolated from an extracted catheter and blood cultures obtained from simultaneous peripheral veins are negative. In this lack of firm data, a group of experts has formulated a series of questions trying to answer them based on the literature, indicating the current deficiencies and offering their own opinion. All authors agree with the conclusions of the manuscript and offer it as a position and discussion paper.

In Vivo Confocal Microscopy Characterization of Candida parapsilosis Keratitis

ABSTRACT

The present clinical case concerns two patients with mycotic keratitis because of Candida parapsilosis in which corneal confocal microscopy presented a characteristic feature of this pathogen. Both described patients used a therapeutic contact lens and administered a therapy with steroid eye drops which are well known predisposing factors for the onset of corneal mycoses. This report can be useful for correctly identifying the pathologic condition and quickly directing the therapy.

The Emerging Pathogen Candida metapsilosis: Biological Aspects, Virulence Factors, Diagnosis, and Treatment

Fungal infections represent a constant and growing menace to public health. This concern is due to the emergence of new fungal species and the increase in antifungal drug resistance. Mycoses caused by Candida species are among the most common nosocomial infections and are associated with high mortality rates when the infection affects deep-seated organs. Candida metapsilosis is part of the Candida parapsilosis complex and has been described as part of the oral microbiota of healthy individuals. Within the complex, this species is considered the least virulent; however, the prevalence has been increasing in recent years, as well as an increment in the resistance to some antifungal drugs. One of the main concerns of candidiasis caused by this species is the wide range of clinical manifestations, ranging from tissue colonization to superficial infections, and in more severe cases it can spread, which makes diagnosis and treatment difficult. The study of virulence factors of this species is limited, however, proteomic comparisons between species indicate that virulence factors in this species could be similar to those already described for C. albicans. However, differences may exist, taking into account changes in the lifestyle of the species. Here, we provide a detailed review of the current literature about this organism, the caused disease, and some sharing aspects with other members of the complex, focusing on its biology, virulence factors, the host-fungus interaction, the identification, diagnosis, and treatment of infection.

The wooden shelf surface and cheese rind mutually exchange microbiota during the traditional ripening process

The rind acts as a protective barrier for internally-bacterial ripened cheeses. Unlike surface-inoculated smear cheeses, centripetal maturation is not assumed to occur in these cheeses. This research was aimed to evaluate the microbial diversity of the wooden shelves used for the ripening of Protected Denomination of Origin (PDO) Pecorino di Filiano and Protected Geographical Indication (PGI) Canestrato di Moliterno cheeses. The microorganisms associated with the rind of these cheeses were also investigated. Both wooden shelf surfaces and cheese rinds were sampled by brushing method to collect their biofilms. Wooden shelves showed levels of total mesophilic microorganisms (TMM) between 5.6 and 7.2 log CFU/cm2, while cheese rinds between 6.1 and 7.8 log CFU/cm2. The major dairy pathogens (Salmonella spp., Listeria monocytogenes, Escherichia coli, and Staphylococcus aureus) were never detected, while mesophilic and thermophilic bacteria dominated the surfaces of all wooden shelves and cheese rinds. LAB community was represented by Enterococcus spp., Leuconostoc spp., and Marinilactibacillus spp. Among yeasts, Debaryomyces spp., Candida spp., were identified, while Aspergillus spp., and Penicillium spp., dominated the community of filamentous fungi. MiSeq Illumina analysis identified 15 phyla, 13 classes, 28 orders, 54 families, and 56 genera among bacteria. Staphylococcus spp. was identified from all wooden surfaces, with a maximum abundance of 71 %. Brevibacterium, Corynebacterium and halophilic bacteria were detected in almost all samples. Regarding fungi, wooden shelves mainly hosted Aspergillus, Penicillium and Debaryomyces hansenii, while cheese rinds especially Penicillium and D. hansenii. Alpha diversity confirmed a strict correlation between the microbiota of wooden shelves and that of cheese rinds for the majority of factories. This study confirmed that the wooden shelves used for cheese ripening are microbiologically active and represent safe systems. Furthermore, the results of this work clarified the transfer flow between wooden shelves and PDO Pecorino di Filiano and PGI Canestrato di Moliterno cheese surfaces: smear-active microorganisms are mainly transferred from wooden shelves to cheese rind, which potentially contribute to the development of the final organoleptic characteristics; meanwhile, cheeses transfer LAB that are potentially involved in defining the safety aspects of the shelves.

Gut mycobiome dysbiosis after sepsis and trauma

BACKGROUND

Sepsis and trauma are known to disrupt gut bacterial microbiome communities, but the impacts and perturbations in the fungal (mycobiome) community after severe infection or injury, particularly in patients experiencing chronic critical illness (CCI), remain unstudied.

METHODS

We assess persistence of the gut mycobiome perturbation (dysbiosis) in patients experiencing CCI following sepsis or trauma for up to two-to-three weeks after intensive care unit hospitalization.

RESULTS

We show that the dysbiotic mycobiome arrays shift toward a pathobiome state, which is more susceptible to infection, in CCI patients compared to age-matched healthy subjects. The fungal community in CCI patients is largely dominated by Candida spp; while, the commensal fungal species are depleted. Additionally, these myco-pathobiome arrays correlate with alterations in micro-ecological niche involving specific gut bacteria and gut-blood metabolites.

CONCLUSIONS

The findings reveal the persistence of mycobiome dysbiosis in both sepsis and trauma settings, even up to two weeks post-sepsis and trauma, highlighting the need to assess and address the increased risk of fungal infections in CCI patients.

Isolation and investigation of external reproduction tract mycoflora in healthy male cats

BACKGROUND

Various infectious agents can infect the male reproductive system.

OBJECTIVES

The aims of this study were to provide current data on fungal and yeast flora of the external organs of reproductive system of male short hair cats including penis and prepuce.

METHODS

In total 28 samples were taken from external genital system of male stray cats using sterilised cotton swabs. Samples were taken based on the absence of any reproductive complications using physical examinations. The samples were transferred to sterilised Stuart transport media and were then incubated in the Sabouraud dextrose agar with chloramphenicol at 32°C for 48 h. The identification of fungi and yeasts was confirmed by germ tube formation test, CHROM agar, urease testing and Corn meal agar medium with Tween 80.

RESULTS

Fungal agents were isolated from 7 (25%) out of 28 male stray cats. Fungal isolates were obtained from the penis and prepuce of 4 (36%) and 7 (100%) male cats, respectively. The most commonly recovered species samples were Candida krusei (3.75%) and Penicillum spp. (6.86%) from the penis and prepuce of the cats, respectively. The external organs of male reproduction of cats were infected with 2-4 different fungal agents. Only 5 (45%) cats were infected with one fungus; however, in 6 (55%) cats, mixed fungal infections were isolated. Cats 3-4 years old had the highest fungal contamination in the prepuce region (4/7), while the penis at this age had the least contamination (1/4).

CONCLUSIONS

It is concluded that the external reproduction organs of male cats could be infected by different fungal agents.

Natural history and prognostic factors of candidemia in kidney transplant recipients: A retrospective, multinational study

BACKGROUND

The natural history of candidemia in kidney transplant recipients (KTR) remains poorly understood. This study aimed to evaluate mortality, prognostic factors and overall graft loss after candidemia in KTRs.

METHODS

This is a retrospective multicentre study enrolling all KTRs ≥15 years old with candidemia diagnosed at hospitals in Brazil, Spain and Italy from 2010 to 2020. Primary endpoints were mortality rates at 14 and 30 days. Secondary endpoints were prognostic factors of 14-day mortality and overall graft loss.

RESULTS

We enrolled 93 KTRs of which 75 were from Brazil. The mean time interval from transplantation to the onset of candidemia was 45.2 ± 61.5 months. 42% of all patients were on haemodialysis, 31.3% had an episode of sepsis and 39% underwent surgery within 30 days before fungemia. European patients were more likely to receive echinocandin (32 vs. 72%, p < .001). 22.7% of Brazilian patients did not receive any antifungal before death. All-cause mortality at 14 days was higher in Brazil (41.3 vs. 11.1%, p = .016). Candida colonisation (OR 6.91 [95% CI: 1.08-44.3], p = .042) and hypotension (OR 4.87 [95% CI: 1.62-14.66], p = .005) were associated with 14-day mortality. Echinocandin treatment had a protective effect (OR 0.19 [95% CI: 0.05-0.73], p = .015). Graft loss at 90 days occurred in 48% of patients (70.7 in Brazil vs. 22.2% in Europe, p < .01).

CONCLUSIONS

Candidemia in KTR is usually documented late after engraftment in patients requiring HD, surgical procedures and dysbiosis secondary to antibiotic use. Mortality was higher in Brazil. Echinocandin therapy was associated with improved survival.

Species distribution and antifungal susceptibility profiles of yeasts isolated from onychomycosis: a cross-sectional study with insights into emerging species

Candida onychomycosis is a common fungal infection affecting the nails, primarily caused by Candida (C.) species. Regarding the increasing trend of Candida onychomycosis and the antifungal resistant phenomenon in recent years, this study aims to evaluate the epidemiological characteristics of Candida onychomycosis, the distribution of emerging species, and the antifungal susceptibility profiles of isolates. Onychomycosis caused by yeast species was confirmed through direct examination and culture of nail scraping among all individuals suspected to have onychomycosis and referred to a medical mycology laboratory between June 2019 and March 2022. Species of yeast isolates were identified using the multiplex PCR and PCR-RFLP methods. The antifungal susceptibility of isolates to common antifungal agents and imidazole drugs was evaluated according to the M-27-A3 CLSI protocol. Among 101 yeast strains isolated from onychomycosis, Candida parapsilosis complex (50.49%) was the most common species, followed by C. albicans (20.79%) and C. tropicalis (10.89%). Rare species of yeasts such as C. guilliermondii and Saccharomyces cerevisiae were also identified by molecular methods. Results obtained from antifungal susceptibility testing showed significant differences in MIC values of isoconazole, fenticonazole, and sertaconazole among different species. Overall, a fluconazole-resistant rate of 3% was found among Candida species. Moreover, there was a statistically significant difference in MICs of fenticonazole and clotrimazole between the two most prevalent causative species, C. parapsilosis complex and C. albicans. Correct identification of the causative agents of onychomycosis and performing susceptibility testing could be helpful in choosing the most appropriate antifungal therapy.

Clinic-mycological spectrum of Candida infection in diabetic foot ulcers in a tertiary care hospital

Background and Purpose

In diabetic foot ulcers, if fungal agents, such as Candida species penetrate the cutaneous or depth of the ulcer, it can increase the wound severity and make it more difficult to heal.

Materials and Methods

A cross-sectional study was performed on 100 diabetic patients with a foot ulcer from December 2019 to November 2020 in northern Iran. Patient data and wound grades were recorded in a questionnaire. Candida infection was confirmed by direct microscopic examination and culture. To identify the causative agent, polymerase chain reaction-restriction fragment length polymorphism using MspI enzyme and the partial amplification of hyphal wall proteins (HWP1) gene were performed.

Results

Mean age of the participants was 62.1 ± 10.8 years old, and 95% of them had type 2 diabetes. Moreover, more than 83% of them had diabetes for a duration of 10 years. In addition, 59% of the patients were male, and 66% > of them had poor education levels. Besides, 99% of them were married, and 52% were rural. Furthermore, 95% of the participants had neuropathic symptoms and 88% used antibiotics. The HbA1C level was > 9% in 69% of them, and the mean ulcer grade of the patients was 2.6±1.05. Candida infection was detected in 13% of the deep tissue and 7% of the tissue surrounding the wound. The predominant Candida isolate was C. parapsilosis (71.5%) and C. albicans (14.3%). Infections caused by filamentous fungi were not detected. There was a statistically significant relationship between Candida infection and gender, rural lifestyle, HbA1C, and ulcer grade.

Conclusion

Mycological evaluations of diabetic foot ulcers are often ignored. The present study revealed that C. parapsilosis is the most common causative agent of deep-seated foot ulcer infection in these patients and may require specific treatment. Therefore, more attention of physicians to Candida infections, early diagnosis, and prompt treatment can help accelerate wound healing and prevent amputation.

Seasonal Variation in Fungi in Beach Sand in Summertime: Stintino (Italy)

BACKGROUND

The goal of this study was to monitor the microbial biodiversity in beach sand that is heavily visited by tourists during the summer, and to determinate whether the high presence of bathers (around 5000 per day) can modify sand microbial composition.

METHODS

Between 2016 and 2020, 150 sand samples were collected from nine different points at La Pelosa beach in Sardinia, Italy. Non-culturing methods were used; DNA extraction and meta-barcode sequencing were performed. All samples were analyzed with sequencing methods for 16S and ITS sequences.

RESULTS

Fungal genera differ on the three beaches and in the winter/summer zones. The ITS sequence showed the most common presence of Candida during summer and Paradendryphiella in the winter. The greatest diversity was found in the dune during winter, while in other parts of the beach, there are differences between bacteria and fungi, particularly in the wash zone during the winter, with high diversity for 16S sequences but low diversity for ITS sequences.

CONCLUSIONS

It appears reasonable that the sands, even on non-urban beaches, should be included in health monitoring programs in addition to the waters, and that access to them should be regulated by limiting the number of bathers with the aim of reducing the presence of pathogenic fungal species.

The first established microsatellite markers to distinguish Candida orthopsilosis isolates and detection of a nosocomial outbreak in China

The infection proportion of Candida orthopsilosis, a member of the C. parapsilosis complex, has increased globally in recent years, and nosocomial outbreaks have been reported in several countries. This study aimed to establish microsatellite loci-based typing method that was able to effectively distinguish among C. orthopsilosis isolates. Three reference C. orthopsilosis genome sequences were analyzed to identify repeat loci. DNA sequences containing over eight bi- or more nucleotide repeats were selected. A total of 51 loci were initially identified, and locus-specific primers were designed and tested with 20 epidemiologically unrelated isolates. Four loci with excellent reproducibility, specificity, and resolution for molecular typing purposes were identified, and the combined discriminatory power (DP, based on 20 epidemiologically unrelated isolates) of these four loci was 1.0. Reproducibility was demonstrated by consistently testing three strains each in triplicate, and stability, demonstrated by testing 10 successive passages. Then, we collected 48 C. orthopsilosis non-duplicate clinical isolates from the China Hospital Invasive Fungal Surveillance Net study to compare the DP of the microsatellite-based typing with internal transcribed spacer (ITS) and amplified fragment length polymorphism (AFLP) typing analyses, using ATCC 96139 as a reference strain. These 49 isolates were subdivided into 12 microsatellite types (COMT1-12), six AFLP types, and three ITS types, while all the isolates with the same COMT belonged to consistent AFLP and ITS type, demonstrating the high DP of our microsatellite-type method. According to our results, COMT12 was found to be the predominant type in China, and COMT5 was the second largest and responsible for causing a nosocomial outbreak. This microsatellite-type method is a valuable tool for the differentiation of C. orthopsilosis and could be vital for epidemiological studies to determine strain relatedness and monitor transmission.

How clean is your ice machine? Revealing microbial amplification and presence of opportunistic pathogens in hospital ice-water machines

BACKGROUND

Ice machines in healthcare facilities have been suspected and even linked to outbreaks and pseudo-outbreaks. Guidelines exist for maintenance of these devices but there is no clear independent infection control standard, and little is known about their microbial contamination.

AIM

To evaluate the microbial contamination, amplification, and presence of opportunistic pathogens in ice-water machines in a healthcare facility.

METHODS

Concentrations of general microbial indicators (heterotrophic plate counts (HPC), total and intact cells), faecal indicators (enterococci) and opportunistic pathogens (Pseudomonas aeruginosa, non-tuberculous mycobacteria (NTM), Candida spp.) were measured in 36 ice-water machines on patient wards of a 772-bed hospital. Profile sampling was performed on five ice-water machines and adjacent faucets to identify sites of microbial proliferation.

FINDINGS

Candida spp. were found in half of ice-water samples while enterococci and P. aeruginosa were present in six and 11 drain inlets respectively. NTM were measured in all ice-water samples and 35 out of 36 biofilms. Pre-filters and ice machines are sites for additional amplification: NTM densities were on average 1.3 log10 higher in water of ice machine flushed 5 min compared to flushed adjacent tap water.

CONCLUSION

Ice machine design needs to be adapted to reduce microbial proliferation. The absence of correlation between HPC densities (current microbial indicators) and NTM concentrations suggests a need for cleaning efficiency indicators better correlated with opportunistic pathogens. Cleaning and disinfection guidelines of ice machines in healthcare facilities need to be improved, especially when ice is given to the most vulnerable patients, and NTM may be an efficiency indicator.

Stewardship-Guided T2Candida Testing Shortens Time to Antifungal Treatment and Reduces Antifungal Usage Among Medical Intensive Care Unit Patients With Septic Shock

Background

Diagnosis of invasive candidiasis (IC) is limited by insensitivity and slow turnaround of cultures. Our objectives were to define the performance of T2Candida, a nonculture test, under guidance of a diagnostic stewardship program, and evaluate impact on time to antifungal initiation and antifungal utilization.

Methods

This was a retrospective study of adult medical intensive care unit (MICU) patients with septic shock for whom T2Candida testing was performed from March 2017 to March 2020. Patients with positive T2Candida results during this period were compared to MICU patients who did not undergo T2Candida testing but had septic shock and blood cultures positive for Candida from January 2016 through March 2020.

Results

Overall, 155 T2Candida tests from 143 patients were included. Nine percent of T2Candida tests were positive compared to 4.5% of blood cultures. Sensitivity, specificity, positive predictive value, and negative predictive value of T2Candida for proven and probable IC were 78%, 95%, 50%, and 99%, respectively. Patients who tested positive for T2Candida (n = 14) were diagnosed earlier and initiated on antifungal therapy sooner than patients with IC (n = 14) diagnosed by blood culture alone (median, 5.6 vs 60 hours; P < .0001). Median antifungal days of therapy/1000 patient-days were 23.3/month preimplementation and 15/month postimplementation (P  = .007). Following a negative T2Candida result, empiric antifungals were either not administered in 58% or discontinued within 72 hours in 96% of patients.

Conclusions

Diagnostic stewardship guided T2Candida testing resulted in reduced time to IC diagnosis, faster initiation of antifungal therapy, and lower antifungal usage among MICU patients with septic shock.

Recurrent copy number variations in the human fungal pathogen Candida parapsilosis

Candida parapsilosis is an opportunistic fungal pathogen with increasing incidence in hospital settings worldwide; however, we lack a comprehensive understanding of the mechanisms promoting its virulence and drug resistance. Bergin et al. systematically quantify the frequency and effect of copy number variation (CNV) across 170 diverse clinical and environmental isolates of C. parapsilosis (Bergin SA, Zhao F, Ryan AP, Müller CA, Nieduszynski CA, Zhai B, Rolling T, Hohl TM, Morio F, Scully J, Wolfe KH, Butler G, 2022, mBio, https://doi.org/10.1128/mbio.01777-22). Using a combination of both short- and long-read whole genome sequencing techniques, they determine the structure and copy number of two CNVs that arose recurrently throughout the evolution of these isolates. Each CNV predominantly amplifies one coding sequence (ARR3 or RTA3); however, the amplitude and recombination breakpoints are variable across the isolates. Amplification of RTA3 correlates with drug resistance and deletion causes drug susceptibility. This study highlights the need for further research into the mechanisms and dynamics of CNV formation and the impact of these CNVs on virulence and drug resistance across diverse fungal pathogens.

Paradigm Shift: Candida parapsilosis sensu stricto as the Most Prevalent Candida Species Isolated from Bloodstream Infections with Increasing Azole-Non-Susceptibility Rates: Trends from 2015-2022 Survey

Candidemia is the fourth most common healthcare-related bloodstream infection. In recent years, incidence rates of Candida parapsilosis have been on the rise, with differences in prevalence and antifungal susceptibility between countries. The aim of the present study was to evaluate temporal changes in prevalence and antifungal susceptibility of C. parapsilosis among other species causing candidemia. All candidemia episodes from January 2015 to August 2022 were evaluated in order to depict time trends in prevalence of C. parapsilosis sensu stricto among all Candida species recovered from blood cultures as well as fluconazole- and voriconazole-non-susceptibility rates. Secondary analyses evaluated time trends in prevalence and antifungal non-susceptibility according to clinical settings. The overall prevalence of C. parapsilosis was observed to increase compared to the prevalence of other Candida species over time (p-trend = 0.0124). From 2019, the number of C. parapsilosis sensu stricto isolates surpassed C. albicans, without an increase in incidence rates. Overall rates of fluconazole- and voriconazole-non-susceptible C. parapsilosis sensu stricto were both 3/44 (6.8%) in 2015 and were 32/51 (62.7%) and 27/51 (52.9%), respectively, in 2022 (85% cross-non-susceptibility). The risk of detecting fluconazole- or voriconazole-non-susceptibility was found to be higher in C. parapsilosis compared to other Candida species (odds ratio (OR) = 1.60, 95% CI [1.170, 2.188], p-value < 0.0001 and OR = 12.867, 95% CI [6.934, 23.878], p-value < 0.0001, respectively). This is the first study to report C. parapsilosis sensu stricto as the most prevalent among Candida spp. isolated from blood cultures, with worrisome fluconazole- and voriconazole-non-susceptibility rates, unparalleled among European and North American geographical regions.

Qualitative and Quantitative Comparison of Aromatic Oil Components and Antifungal Effects of Cymbopogon flexuosus Obtained with Supercritical CO2, Microwave-Ultrasonic, Steam Distillation, and Hydrodistillation Extraction Techniques

Cymbopogon flexuosus is a highly valued botanical species with significant applications in the food and food supplement industries, medicine, and cosmetics. The effects of four extraction techniques, supercritical CO2, microwave-ultrasonic, steam distillation, and hydrodistillation techniques, on the yield, phytochemical constituents, and antifungal activity against nine fungal species of Cymbopogon flexuosus aromatic oil (AO) were explored in this investigation. Gas chromatography connected with a mass spectrometry apparatus was employed for the qualitative and quantitative analyses of the investigated plant AOs. In addition, using the broth microdilution method, minimum inhibitory concentrations (MICs) were calculated for several fungi species. The supercritical CO2 method gave the highest yield of AO (11.62 ± 0.03 (w/w)) followed by the microwave-ultrasonic method (1.55 ± 0.05% (w/w)) and the steam distillation method (1.24 ± 0.04% (w/w)), while the hydrodistillation methods gave the lowest yield (1.17 ± 0.01 (w/w)). In addition, eighteen molecules were specified in the AOs obtained with the supercritical CO2, microwave-ultrasonic, steam distillation, and hydrodistillation techniques, which constituted 99.36, 98.6, 98.21, and 98.31% (v/v) of the total oils, respectively. Additionally, linalyl acetate was the trending molecule in the microwave-ultrasonic and steam distillation methods, representing 24.61 and 24.34% (v/v), respectively, while geranial was the dominant molecule in the AOs extracted with the hydrodistillation and supercritical CO2 extraction techniques (27.01 and 25.6% (v/v), respectively). The antifungal screening results revealed that the tested C. flexuosus AOs have potential antifungal effects against all the screened fungi species. The antifungal effect of the AOs extracted with the steam distillation and microwave-ultrasonic methods was remarkable compared with that of the commercial antifungal drug Fluconazole. However, the AOs extracted with these two methods have a more potent antifungal effect against Candida parapsilosis than that of Fluconazole with MICs of 3.13 ± 0.01, 3.13 ± 0.01, and 6.25 ± 0.91 µg/mL, respectively. The same effects were also observed against Trichophyton rubrum with MICs of 6.25 ± 0.91 µg/mL, respectively. The results of this investigation demonstrated that the steam distillation and microwave-ultrasonic methods are promising processes for the extraction of C. flexuosus AO with a potent antifungal effect. This may be an advantage for the utilization of C. flexuosus AO over some antifungal synthetic agents commonly utilized as medicines, preservatives, food additives, cosmetics, and nutrient supplements.

Biofilm Formation in Medically Important Candida Species

Worldwide, the number of infections caused by biofilm-forming fungal pathogens is very high. In human medicine, there is an increasing proportion of immunocompromised patients with prolonged hospitalization, and patients with long-term inserted drains, cannulas, catheters, tubes, or other artificial devices, that exhibit a predisposition for colonization by biofilm-forming yeasts. A high percentage of mortality is due to candidemia caused by medically important Candida species. Species of major clinical significance include C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, C. krusei, and C. auris. The association of these pathogenic species in the biofilm structure is a serious therapeutic problem. Candida cells growing in the form of a biofilm are able to resist persistent therapy thanks to a combination of their protective mechanisms and their ability to disseminate to other parts of the body, thus representing a threat from the perspective of a permanent source of infection. The elucidation of the key mechanisms of biofilm formation is essential to progress in the understanding and treatment of invasive Candida infections.

The evaluation of Candida-related central line-related bloodstream infections in pediatric cancer patients: A pre- and post-intervention study

Aim/Objections

The purpose of this study was to assess the efficacy of a central line maintenance bundle in preventing catheter-related (implanted venous access devices, port) Candida bloodstream infections.

Methods

The study encompassed two distinct time periods, namely, pre-bundle and bundle. The number of catheter-related bloodstream infections (CRBSI) episodes per catheter days for each timeframe was determined.

Findings/Results

Upon implementation of the central line bundle, the rate of CRBSI reduced significantly from 4.27 per 1000 central line days in the pre-bundle period to 1.0 per 1000 central line days in the bundle period (p < .001).

Discussion

Using a central line bundle to avoid CRBSIs in pediatric cancer patients with ports led to a significant decrease in Candida species-related CRBSIs.

Clinical, Epidemiological and Laboratory Features of Invasive Candida parapsilosis Complex Infections in a Brazilian Pediatric Reference Hospital during the COVID-19 Pandemic

The present study aimed to describe the clinical, epidemiological and laboratory characteristics of invasive candidiasis by C. parapsilosis complex (CPC) in a Brazilian tertiary pediatric hospital during the COVID-19 pandemic. Clinical samples were processed in the BACT/ALERT® 3D system or on agar plates. Definitive identification was achieved by MALDI-TOF MS. Antifungal susceptibility was initially analyzed by the VITEK 2 system (AST-YS08 card) and confirmed by the CLSI protocol. Patient data were collected from the medical records using a structured questionnaire. CPC was recovered from 124 patients over an 18-month period, as follows: C. parapsilosis (83.87%), C. orthopsilosis (13.71%) and C. metapsilosis (2.42%). Antifungal resistance was not detected. The age of the patients with invasive CPC infections ranged from <1 to 18 years, and most of them came from oncology-related sectors, as these patients were more affected by C. parapsilosis. C. orthopsilosis infections were significantly more prevalent in patients from critical care units. Invasive infections caused by different pathogens occurred in 75 patients up to 30 days after the recovery of CPC isolates. Overall, 23 (18.55%) patients died within 30 days of CPC diagnosis. Catheter removal and antifungal therapy were important measures to prevent mortality. COVID-19 coinfection was only detected in one patient.

Candida parapsilosis cell wall proteins-CPAR2_404800 and CPAR2_404780-Are adhesins that bind to human epithelial and endothelial cells and extracellular matrix proteins

One of the initial steps necessary for the development of Candida infections is the adherence to the host tissues and cells. Recent transcriptomic studies suggest that, in Candida parapsilosis-a fungal infectious agent that causes systemic candidiasis in immunosuppressed individuals-the adhesion is mediated by pathogen cell-exposed proteins belonging to the agglutinin-like sequence (Als) family. However, to date, the actual interactions of individual members of this family with human cells and extracellular matrix (ECM) have not been characterized in detail. In the current study, we focused attention on two of these C. parapsilosis Als proteins-CPAR2_404800 and CPAR2_404780-that were proteomically identified in the fungal cell wall of yeasts grown in the media suitable for culturing human epithelial and endothelial cells. Both proteins were extracted from the cell wall and purified, and using a microplate binding assay and a fluorescence microscopic analysis were shown to adhere to human cells of A431 (epithelial) and HMEC-1 (endothelial) lines. The human extracellular matrix components that are also plasma proteins-fibronectin and vitronectin-enhanced these interactions, and also could directly bind to CPAR2_404800 and CPAR2_404780 proteins, with a high affinity (KD in a range of 10-7 to 10-8  M) as determined by surface plasmon resonance measurements. Our findings highlight the role of proteins CPAR2_404800 and CPAR2_404780 in adhesion to host cells and proteins, contributing to the knowledge of the mechanisms of host-pathogen interactions during C. parapsilosis-caused infections.

A Novel One Health Approach concerning Yeast Present in the Oral Microbiome of the Endangered Rio Skate (Rioraja agassizii) from Southeastern Brazil

The current climate change scenario caused by anthropogenic activities has resulted in novel environmental pressures, increasing the occurrence and severity of fungal infections in the marine environment. Research on fungi in several taxonomic groups is widespread although not the case for elasmobranchs (sharks and rays). In this context, the aim of the present study was to screen the oral fungal microbiota present in artisanally captured Rioraja agassizii, a batoid that, although endangered, is highly fished and consumed worldwide. Oropharyngeal samples were obtained by swabbing and the samples were investigated using morphological and phenotypic methods by streaking on Sabouraud Dextrose Agar (SDA) and subculturing onto CHROMagar Candida (BD Difco) and CHROMagar Candida Plus (CHROMagarTM), as well as molecular techniques by amplification of the ITS1-5.8S-ITS2 ribosomal DNA region and a MALDI-TOF MS assessment. The findings indicated the presence of Candida parapsilosis (seven isolates), Candida duobushaemulonii (one isolate) and Rhodotorula mucilaginosa (three isolates), several of these reported for the first time in Rioraja agassizii. In addition, a 100% agreement between the MALDI-TOF results and partial ITS region sequencing was noted, demonstrating that the MALDI-TOF MS is a rapid and effective alternative for yeast identification in Rioraja agassizii isolates and potentially in other elasmobranch species. These findings highlight the need for further research to determine the potential impact on elasmobranch health, ecology, and commercial fisheries. Furthermore, this research is paramount in a One Health framework and may be employed to predict elasmobranch responses to an evolving ocean, keep healthy populations in check, monitor species, and assess the public health consequences of consuming these species.

Candida parapsilosis sensu stricto Antifungal Resistance Mechanisms and Associated Epidemiology

Fungal diseases cause millions of deaths per year worldwide. Antifungal resistance has become a matter of great concern in public health. In recent years rates of non-albicans species have risen dramatically. Candida parapsilosis is now reported to be the second most frequent species causing candidemia in several countries in Europe, Latin America, South Africa and Asia. Rates of acquired azole resistance are reaching a worrisome threshold from multiple reports as in vitro susceptibility testing is now starting also to explore tolerance and heteroresistance to antifungal compounds. With this review, the authors seek to evaluate known antifungal resistance mechanisms and their worldwide distribution in Candida species infections with a specific focus on C. parapsilosis.

Synthesis and Antimicrobial Activity of New Mannich Bases with Piperazine Moiety

A series of novel Mannich bases were designed, synthesized, and screened for their antimicrobial activity. The target compounds were synthesized from 4-(3-chlorophenyl)-5-(3-fluorophenyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione and different piperazine derivatives. The structures of the products were confirmed by ¹H and ¹³C NMR and elemental analysis. The activity of piperazine derivatives against bacteria (Gram-positive: Staphylococcus epidermidis, Staphylococcus aureus, Micrococcus luteus, Bacillus cereus, and Bacillus subtilis; Gram-negative: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Proteus mirabilis) and yeasts (Candida glabrata, Candida krusei, and Candida parapsilosis) was determined by the minimum inhibitory concentration and minimum bactericidal concentration values. Significant activity was observed against Gram-positive bacteria, mainly staphylococci (PG7-PG8) and bacteria of the genes of Micrococcus and Bacillus (PG1-3), as well as selected strains of Gram-negative bacteria, including bacteria of the Enterobacteriaceae family (PG7), while all tested compounds showed high fungistatic activity against Candida spp. yeasts, especially C. parapsilosis, with MICs ranging from 0.49 µg/mL (PG7) to 0.98 µg/mL (PG8) and 62.5 µg/mL (PG1-3). In conclusion, the results obtained confirm the multidirectional antimicrobial activity of the newly synthesized piperazine derivatives. Furthermore, in silico studies suggest that the tested compounds are likely to have good oral bioavailability. The results obtained will provide valuable data for further research into this interesting group of compounds. The library of compounds obtained is still the subject of pharmacological research aimed at finding new interesting biologically active compounds.

Evaluation of the In Vitro Antifungal Activity of Novel Arylsulfonamides against Candida spp

The antifungal activity of molecules belonging to the arylsulfonamide chemotype has previously been demonstrated. Here, we screened arylsulfonamide-type compounds against a range of Candida spp. and further established the structure-activity relationship based on a "hit compound". A series of four sulfonamide-based compounds, N-(4-sulfamoylbenzyl) biphenyl-4-carboxamide (3), 2,2-diphenyl-N-(4-sulfamoylbenzyl) acetamide (4), N-(4-sulfamoylphenethyl) biphenyl-4-carboxamide (5) and 2,2-diphenyl-N-(4-sulfamoylphenethyl) acetamide (6), were tested against the American Type Culture Collection (ATCC) and clinical strains of C. albicans, C. parapsilosis and C. glabrata. Based on the fungistatic potential of prototype 3, a further subset of compounds, structurally related to hit compound 3, was synthesized and tested: two benzamides (10-11), the related amine 4-[[(4-4-((biphenyl-4-ylmethylamino)methyl) benzenesulfonamide (13) and the corresponding hydrochloride, 13^.HCl. Both amine 13 and its hydrochloride salt had fungicidal effects against Candida glabrata strain 33 (MFC of 1.000 mg/mL). An indifferent effect was detected in the association of the compounds with amphotericin B and fluconazole. The cytotoxicity of the active compounds was also evaluated. This data could be useful to develop novel therapeutics for topical use against fungal infections.

In vitro evaluation of biofilm formation by Candida parapsilosis and Enterobacter cloacae. Scanning electron microscopy and efficacy of antimicrobial combinations study

Fungal-bacterial infections are being increasingly recognized in clinical settings, and the interaction between these species in polymicrobial biofilms often lead to infections that are highly resistant to treatment. In this in vitro study, we analyzed the formation of mixed biofilms using clinically isolated Candida parapsilosis and Enterobacter cloacae. Additionally, we assessed the potential of conventional antimicrobials, both alone and in combination, for treating polymicrobial biofilms built by these human pathogens. Our results demonstrate that C. parapsilosis and E. cloacae are capable of forming mixed biofilms, as confirmed by scanning electron microscopy. Interestingly, we found that colistin alone or in combination with antifungal drugs was highly effective reducing up to 80% of the total biomass of polymicrobial biofilms.

Green Ultrasound-Assisted Synthesis of Surface-Decorated Nanoparticles of Fe3O4 with Au and Ag: Study of the Antifungal and Antibacterial Activity

This work proposes a sonochemical biosynthesis of magnetoplasmonic nanostructures of Fe₃O₄ decorated with Au and Ag. The magnetoplasmonic systems, such as Fe₃O₄ and Fe₃O₄-Ag, were characterized structurally and magnetically. The structural characterizations reveal the magnetite structures as the primary phase. Noble metals, such as Au and Ag, are present in the sample, resulting in a structure-decorated type. The magnetic measurements indicate the superparamagnetic behavior of the Fe₃O₄-Ag and Fe₃O₄-Au nanostructures. The characterizations were carried out by X-ray diffraction and scanning electron microscopy. Complementarily, antibacterial and antifungal assays were carried out to evaluate the potential properties and future applications in biomedicine.

Yeast community succession in cow dung composting process

Yeast complexes in the composting process of cow dung prepared to fertilize the soil for growing vegetables and fruits were studied. The average abundance of yeasts changed during the four temperature stages of the composting process. The highest abundance of yeasts, 1.38 × 10⁴ cfu/g, was observed in the second stage of heating from 20 to 40 °C; the lowest was studied in the stage with the highest temperature (65 °C), 1.68 × 10³ cfu/g. A total of 19 yeast species were observed and identified: 11 ascomycetes and 8 basidiomycetes, belonging to five subphyla of Fungi: Saccharomycotina (10), Pezizomycotina (1), Agaricomycotina (5), Pucciniomycotina (2), and Ustilaginomycotina (1). The greatest diversity of yeasts was found in the initial (20 °C) and second (heating up to 40 °C) temperature stages of composting (Aureobasidium pullulans (yeast-like fungus), Candida parapsilosis, Candida saitoana, Candida santamariae, Candida tropicalis, Curvibasidium cygneicollum, Cutaneotrichosporon moniliforme, Debaryomyces fabryi, Debaryomyces hansenii, Filobasidium magnum, Kazachstania sp., Moesziomyces bullatus, Naganishia globosa, Papiliotrema flavescens, Rhodotorula mucilaginosa, Scheffersomyces insectosa, Torulaspora delbrueckii, Vanrija musci), and the lowest in the stage of maximum heating (65 °C) (C. parapsilosis, C. tropicalis, Cyberlindnera jadinii).The opportunistic yeasts C. parapsilosis and C. tropicalis were obtained not only in the initial, second and third temperature stages of the composting process, but also in mature compost in the final stage prepared for soil application. This study shows that the cow dung, used in the farm studied did not meet the microbiological safety criteria. The reduction of opportunistic yeast species was not achieved with the composting method used. The likelihood of these species entering agricultural products via compost and soil and developing as endophytes in the internal tissues of fruits is very high. Since some strains of opportunistic Candida species from cow dung exhibited virulent characteristics (they produced hydrolytic enzymes and were resistant to antifungal compounds), additional phenotypic and genetic studies of the compost strains and their comparison with clinical isolates should be pursued.

Risk Factors and Characteristics of Candidemia After Cardiac Surgery in Pediatric Patients in Central Israel

BACKGROUND

Candidemia is a serious complication in pediatric patients with congenital heart defects (CHD) after cardiac surgery. Information about the epidemiology, clinical characteristics and risk factors for candidemia in this vulnerable population remains limited.

METHODS

This retrospective case-control study was conducted in 2 pediatric intensive care units between 2004 and 2019. All patients <18 years old who developed candidemia following cardiac surgery were included. Each case was matched with 2 control patients based on age and date of surgery. Multivariable logistic regression analysis was conducted to determine the risk factors for postoperative candidemia.

RESULTS

Thirty-five candidemia cases were identified and matched to 70 control cases. The incidence of candidemia was 6.3 episodes per 1000 admissions. The median age for candidemia cases was 4 months. The attributable mortality was 28.5%. The predominant (54%) pathogens isolated were non- albicans Candida species, of which C. parapsilosis isolates demonstrated high resistance to fluconazole (70%). Independent risk factors associated with candidemia included cumulative antibiotic exposure for ≥4 days [OR: -4.3; 95% confidence interval (CI): 1.3-14.6; P = 0.02], the need for total parenteral nutrition or peritoneal dialysis (OR: -6.1; 95% CI: 2-18.8; P = 0.001), male sex (OR: 6.2; 95% CI: 1.9-20.3; P = 0.002) and delayed sternal closure≥2 days (OR: -3.2; 95% CI: 1-11.2; P = 0.05).

CONCLUSIONS

Postoperative candidemia in children with CHD is an uncommon but severe complication. Our study revealed an unexpectedly high frequency of fluconazole-resistant C. parapsilosis as the main cause of non- albicans candidemia. In addition to confirming previously recognized risk factors, our results reveal new potential risk factors such as delayed sternal closure and male sex.

The antifungal effect induced by itraconazole in Candida parapsilosis largely depends on the oxidative stress generated at the mitochondria

In Candida parapsilosis, homozygous disruption of the two genes encoding trehalase activity increased the susceptibility to Itraconazole compared with the isogenic parental strain. The fungicidal effect of this azole can largely be counteracted by preincubating growing cells with rotenone and the protonophore 2,4-Dinitrophenol. In turn, measurement of endogenous reactive oxygen species formation by flow cytometry confirmed that Itraconazole clearly induced an internal oxidative stress, which can be significantly abolished in rotenone-exposed cells. Analysis of the antioxidant enzymatic activities of catalase and superoxide dismutase pointed to a moderate decrease of catalase in trehalase-deficient mutant cells compared to the wild type, with an additional increase upon addition of rotenone. These enzymatic changes were imperceptible in the case of superoxide dismutase. Alternative assays with Voriconazole led to a similar profile in the results regarding cell growth and antioxidant activities. Collectively, our data suggest that the antifungal action of Itraconazole on C. parapsilosis is dependent on a functional mitochondrial activity. They also suggest that the central metabolic pathways in pathogenic fungi should be considered as preferential antifungal targets in new research.

Recent increase in fluconazole-nonsusceptible Candida parapsilosis in a global surveillance with the expansion of the Erg11 Y132F genotype and a rapid detection method for this alteration

We evaluated the rates of fluconazole nonsusceptibility among 1103 Candida parapsilosis isolates collected globally from 2018 to 2021. These rates were <10.3% until 2020 but increased to 15.4% in 2021. Fluconazole-nonsusceptible C. parapsilosis rates were highest in Europe (96/466 isolates; 20.6%) followed by the US (23/386; 6.0%). As the Erg11 Y132F alteration has been a common fluconazole nonsusceptibility mechanism in C. parapsilosis, we developed a PCR assay to detect this mutation. This assay displayed 100% sensitivity and specificity when tested against 56 isolates previously submitted to whole genome sequencing. The Erg11 Y132F alteration was detected in 83.2% of the isolates (104/125) collected during 2018 to 2021 using the PCR assay. The highest rates of the Erg11 Y132F genotype were observed among fluconazole-nonsusceptible isolates from Europe (93.8%), followed by the US (60.9%). An increase in fluconazole-nonsusceptible C. parapsilosis was documented in 2021. Most isolates from Europe and the US carried the Y132F Erg11 alteration that has been reported in various countries.

Molecular Investigation of the Fatal Bloodstream Candida orthopsilosis Infection Case following Gastrectomy

Candida orthopsilosis represents a closely related cryptic genospecies of Candida parapsilosis complex-misidentified in routine diagnostic assays. This is emerging in settings where central venous catheters, invasive medical interventions, and echinocandin treatments are most likely to be used. A 59-year-old, non-neutropenic male patient, was admitted to an intensive care unit (ICU) due to respiratory distress syndrome, following a partial gastrectomy. As a result of duodenal stump leakage, re-laparotomy was required, abdominal drains were provided and central line catheters were exchanged. Multiple isolates of Candida orthopsilosis drawn from consecutive blood cultures were identified, despite ongoing echinocandin therapy and confirmed in vitro echinocandins susceptibility of the isolated strain. Species identification was verified via ITS region sequencing. Herein, we report the well-documented—per clinical data and relevant laboratory diagnosis—first case of a bloodstream infection caused by Candida orthopsilosis in Poland.

Bioactive Potential of Elderberry (Sambucus nigra L.): Antioxidant, Antimicrobial Activity, Bioaccessibility and Prebiotic Potential

Due to its abundance of physiologically active ingredients, one of the oldest medicinal herbs, elderberry (EB) Sambucus nigra L., is beneficial for both therapeutic and dietary purposes. This study determined the bioaccessibility of the phenolic compounds and the prebiotic potential of the polyphenols from freeze-dried EB powder (FDEBP), along with the antioxidant and antimicrobial activities of this extract. The most significant phenolic compounds in black EB are represented by anthocyanins (41.8%), predominating cyanidin-sambubiosides and cyanidin-glucosides (90.1% of the identified anthocyanins). The FRAP assay obtained the highest antioxidant activity value (185 ± 0.18 μmol Fe2+/g DW). The most sensitive to the antimicrobial activity of the extract was proven to be Staphylococcus aureus, and Pseudomonas aeruginosa had the lowest minimum inhibitory concentration of 1.95 mg/mL. To determine the prebiotic potential of the polyphenols, the cell growth of five probiotic strains (Lactobacillus plantarum, L. casei, L. rhamnosus, L. fermentum and Saccharomyces boulardii) was tested. The influence on cell growth was positive for all five probiotic strains used. Overall, the most significant increase (p < 0.05) was recorded at 1.5% FDEBP, on S. boulardii with a growth index (GI) of 141.02%, very closely followed by GI at 0.5% and 1% concentrations. The stability of the total phenolic compounds through simulated gastronitestinal digestion was increased (93%), and the bioaccessibility was also elevated (75%).

Candida parapsilosis Cell Wall Proteome Characterization and Effectiveness against Hematogenously Disseminated Candidiasis in a Murine Model

Candida parapsilosis poses huge treatment challenges in the clinical settings of South Africa, and often causes infections among immunocompromised patients and underweight neonates. Cell wall proteins have been known to play vital roles in fungal pathogenesis, as these are the first points of contact toward environments, the host, and the immune system. This study characterized the cell wall immunodominant proteins of pathogenic yeast C. parapsilosis and evaluated their protective effects in mice, which could add value in vaccine development against the rising C. parapsilosis infections. Among different clinical strains, the most pathogenic and multidrug-resistant C. parapsilosis isolate was selected based on their susceptibility towards antifungal drugs, proteinase, and phospholipase secretions. Cell wall antigens were prepared by β-mercaptoethanol/ammonium bicarbonate extraction from selected C. parapsilosis strains. Antigenic proteins were identified using LC–MS/MS, where 933 proteins were found, with 34 being immunodominant. The protective effect of the cell wall immunodominant proteins was observed by immunizing BALB/c mice with cell wall protein extracts. After the immunization and booster, the BALC/c mice were challenged with a lethal dose of C. parapsilosis. In vivo results demonstrated increased survival rates and lower fungal burden in vital organs in the immunized mice compared to the unimmunized mice, thereby confirming the immunogenic property of cell wall-associated proteins of C. parapsilosis. Therefore, these results advocated the potential of these cell wall proteins to act as biomarkers for the development of diagnostic assays and/or vaccines against infections caused by C. parapsilosis.

The Role of the Mycobiome in Women’s Health

Although the human bacteriome and virome have gained a great deal of attention over the years, the human mycobiome has been far more neglected despite having significant value and implications in human health. In women, mycobiome profiles in breastmilk, vaginal regions, the gut, skin, and the oral cavity can provide insight into women’s health, diseases, and microbiome dysbiosis. Analyses of mycobiome composition under factors, such as health, age, diet, weight, and drug exposure (including antibiotic therapies), help to elucidate the various roles of women’s mycobiome in homeostasis, microbiome interactions (synergistic and antagonistic), and health. This review summarizes the most recent updates to mycobiome knowledge in these critical areas.