Search Results (60)

We analyzed data on pediatric invasive fungal diseases of the central nervous system (CNS-IFDs) reported by five of a total of eight Pediatric Hematology-Oncology Departments in Greece for 16 years (2007–2022). A total of twelve patients (11 boys, median age: 9.5 years, range: 2–16) were reported suffering from CNS-IFDs. The underlying malignancy was acute lymphoblastic leukemia in 9/12 and acute myeloid leukemia, Ewing sarcoma, and rhabdomyosarcoma in one each. Eleven patients presented with CNS-related symptoms (i.e., seizures, headache, cerebral palsy, ataxia, hallucination, seizures, blurred vision, amaurosis). All patients had pathological MRI findings. Multifocal fungal disease was observed in 6/12 patients. Nine proven and three probable CNS-IFD cases were diagnosed. Causative pathogens in proven cases were Aspergillus spp. and Candida albicans (n = 2 each), Mucor spp., Rhizopus arrhizus, Absidia spp., Fusarium oxysporum and Cryptococcus neoformans (n = 1 each). Causative pathogens in probable cases were Aspergillus spp. (n = 2) and Candida spp. (n = 1). All patients received appropriate antifungal therapy (median duration: 69.5 days, range 19–364). Two patients underwent additional surgical treatment. Six patients were admitted to the Intensive Care Unit due to complications. Three patients (25%) died, two due to IFD and one due to an underlying disease. Early recognition and prompt intervention of CNS-IFDs may rescue the patients and improve overall survival. Full article

Synanthropic birds might play an important role as reservoirs of many zoonotic endoparasites; however, little information is available on many parasites and their prevalence. Here, we use an approach based on targeted metagenomic detection through the use of DNA metabarcoding of faecal samples to screen for circulating parasites in alien parakeets (Myiopsitta monachus and Psittacula krameri) and urban landfill-feeding storks (Ciconia ciconia) and gulls (Larus fuscus). We focus especially on potentially zoonotic parasites, with the aim of better understanding the zoonotic risk that these birds’ faeces may pose. We detected a total of 23 genera of eukaryotic parasites: six fungi, three protists, five nematodes, two cestodes and seven trematodes. Among them, six stood out for their relevance to human health: Cryptococcus spp., Aspergillus spp. and Candida spp. (fungi); Cryptosporidium spp. (a protist); and Ascaris spp. and Halicephalobus spp. (nematodes). In parakeets, we detected Cryptococcus spp. and Ascaris spp., the latter being detected in 10–20% of the samples. In the White Stork and the Lesser Black-backed Gull, we found a high prevalence of Aspergillus spp. (in 15% and 50% of the samples, respectively) and Candida spp. (in 63% and 82% of the samples, respectively), and the presence of Cryptosporidium spp. in 10% of the samples. We detected Halicephalobus spp. in one gull sample (2%). Our results show that synanthropic birds may act as vectors and reservoirs of zoonotic parasites and their faeces could pose a risk to human health associated with the zoonotic parasites present in them. This should be taken into account when developing management plans for urban populations of these bird species. Full article

This study aimed to estimate the prevalence of cryptococcal antigenemia detected by lateral flow assay (LFA) in AIDS patients and its accuracy in the diagnosis of cryptococcosis. Conducted at a university hospital in Brazil from March 2015 to July 2017, it included AIDS patients over 18 years old with a CD4+ count ≤ 200 cells/mm³. Cryptococcal antigen (CrAg) detection using LFA and latex agglutination (LA), along with blood and urine cultures, were performed. The reference standard was the identification of Cryptococcus spp. in clinical specimens through microbiological or histopathological examination. Among 230 patients, the prevalence of CrAg detected by LFA (CrAg LFA) was 13.0%. Factors associated with cryptococcal antigenemia included fever, vomiting, seizures, and a lack of antiretroviral therapy. The sensitivity and specificity of CrAg LFA were 83.9% and 98.0%, respectively. The positive predictive value (PPV) was 86.7%, the negative predictive value (NPV) was 97.5%, and overall accuracy was 96.1%. Cross-reactions were observed in patients with histoplasmosis and paracoccidioidmycosis, but not with aspergillosis or positive rheumatoid factor. The study concludes that the LFA is a useful tool for detecting cryptococcal antigenemia in severely immunocompromised AIDS patients due to its high NPV, specificity, and PPV. Full article

Cryptococcal infection poses a significant global public health challenge, particularly in regions near the equator. In this review, we offer a succinct exploration of the Cryptococcus spp. genome and various molecular typing methods to assess the burden and genetic diversity of cryptococcal pathogens in the environment and clinical isolates. We delve into a detailed discussion on the molecular pathogenesis and diagnosis of immune reconstitution inflammatory syndrome (IRIS) associated with cryptococcosis, with a specific emphasis on cryptococcal meningitis IRIS (CM-IRIS). Our examination includes the recent literature on CM-IRIS, covering host cellulomics, proteomics, transcriptomics, and genomics. Full article

An amplicon metagenomic approach based on the ITS2 region of fungal rDNA was used to investigate the diversity of fungi associated with mature strawberries collected from a volcanic orchard and open-air market stands. Based on the Kruskal–Wallis test, no statistically significant differences were observed in both non-phylogenetic and phylogenetic alpha diversity indices. According to beta diversity analyses, significant differences in fungal communities were found between groups (orchard vs. market). Taxonomic assignment of amplicon sequence variables (ASVs) revealed 7 phyla and 31 classes. The prevalent fungal phyla were Basidiomycota (29.59–84.58%), Ascomycota (15.33–70.40%), and Fungi-phy-Insertae-sedis (0.45–2.89%). The most predominant classes among the groups were Saccharomycetes in the market group, and Microbotryomycetes and Tremellomycetes in the orchard group. Based on the analysis of microbiome composition (ANCOM), we found that the most differentially fungal genera were Hanseniaspora, Kurtzmaniella, and Phyllozyma. Endophytic yeasts Curvibasidium cygneicollum were prevalent in both groups, while Candida railenensis was detected in fruits originating only from the market. In addition, Rhodotorula graminis (relative abundance varying from 1.7% to 21.18%) and Papiliotrema flavescens (relative abundance varying from 1.58% to 16.55%) were detected in all samples regardless of origin, while Debaryomyces prosopidis was detected in samples from the market only, their relative abundance varying with the sample (from 0.80% to 19.23%). Their role in fruit quality and safety has not been yet documented. Moreover, several clinically related yeasts, such as Meyerozyma guilliermondii and Candida parapsilosis, were detected in samples only from the market. Understanding the variety and makeup of the mycobiome in ripe fruits during the transition from the orchard to the market is crucial for fruit safety after harvest. Full article

The importance of fungal infections, particularly those caused by yeasts, is increasing among the medical community. Candida albicans and Cryptococcus neoformans are amongst the high-priority fungal species identified by the World Health Organization (WHO) and are considered in the critical group, while Candida krusei is included in the medium-priority group. The cyclam salt H₄[H₂(^4-CF3PhCH₂)₂Cyclam]Cl₄ proved to be active against the growth of these three yeasts, and the aim of this work was to verify its interference with their virulence mechanisms, whether shared or unique. H₄[H₂(^4-CF3PhCH₂)₂Cyclam]Cl₄ significantly inhibited biofilm production and catalase activity, being able to interfere with C. albicans dimorphic transition and C. neoformans melanin production. At the minimal inhibitory concentration (MIC) values, H₄[H₂(^4-CF3PhCH₂)₂Cyclam]Cl₄ had no antioxidant effect, as determined by the DPPH method. When using the RAW264.7 macrophage cell line, H₄[H₂(^4-CF3PhCH₂)₂Cyclam]Cl₄ reduced nitric oxide (NO) detection (the Griess reaction), but this effect was associated with a significant toxic effect on the cells. Full article

Cetaceans, which are integral to marine ecosystems, face escalating anthropogenic threats, including climate change and pollution, positioning them as critical sentinel species for ocean and human health. This review explores the neglected realm of non-Candida yeasts in cetaceans, addressing the gaps in the understanding of their prevalence, pathogenicity, and environmental impacts. By examining identified species such as Cryptococcus spp., Paracoccidioides spp., and several dimorphic fungi, this review emphasizes global prevalence, epidemiology and ecology, pathogenicity, and potential zoonotic implications. It also discusses the fine line between yeast commensalism and pathogenicity by considering environmental influences such as pollution, climate shifts, and immune suppression. Environmental impact discussions delve into how rising ocean temperatures and pollution can modify yeast mycobiota, potentially affecting marine host health and broader ecosystem dynamics. The cetacean’s unique physiology and ecological niches are considered, highlighting potential impacts on behaviors, reproductive success, and survival rates. Identifying crucial knowledge gaps, the review calls for intensified research efforts, employing advanced molecular techniques to unravel the cetacean mycobiome. Systematic studies on yeast diversity, antifungal susceptibility, and their influence on environmental and ecosystem health are proposed, and the balance between commensal and pathogenic species emphasizes the significance of the One Health approach. In conclusion, as marine mammals face unprecedented challenges, unveiling non-Candida yeasts in cetaceans emerges as a critical endeavor with far-reaching implications for the conservation of marine ecosystems and for both animal and human public health. Full article

Immunoassays for cell wall mannans that are excreted into serum and urine have been used as an aid in the diagnosis of many disseminated fungal infections, including coccidioidomycosis. Antigen-detection immunoassays are critically dependent on the detection of an analyte, such as mannan, by antibodies that are specific to the analyte. The goal of this study was to evaluate the extent of cross-reactivity of polyclonal antibodies raised against Coccidioides spp. Analysis of antigenic relatedness between mannans from C. posadasii and C. immitis spherules and mycelia showed complete relatedness when evaluated by the method of Archetti and Horsfall, which was originally used to study the antigenic relationships between Influenzae virus isolates. In a further effort to validate the suitability of the antigenic relatedness calculation methodology for polysaccharide antigens, we also applied the method of Archetti and Horsfall to published results that had previously identified the major capsular serotypes of Cryptococcus species. The results of this analysis showed that Archetti and Horsfall’s antigenic relatedness calculation correctly identified the major cryptococcal serotypes. Together, these results suggest that the method is applicable to polysaccharide antigens, and that immunoassays that detect Coccidioides mannans are likely to have good reactivity across Coccidioides species (inclusivity) due to the species’ high level of antigenic relatedness. Full article

Aquatic animals are continually being exposed to stressors under farming conditions, increasing risks to gut health that result in dysbiosis. Since restrictions are imposed on the frequent use of antibiotics in aquaculture, there is emerging demand for economically viable, environmentally safe, and sustainable alternatives for the intensive production of aquaculture species. The application of beneficial microorganisms as probiotics has been suggested and widely practiced in recent times. Bacteria and fungi are ubiquitous microorganisms that can grow in various environments where organic substrates are available. Being rich in nutrients, a fish’s aquatic environment and gastrointestinal tract confer a favorable culture milieu for the microorganisms. However, the colonization and probiotic potential of fungi and mycelial bacteria resembling fungi (actinobacteria), either in the culture environment or within the gastrointestinal tracts of fish, have received less emphasis. Apart from bacilli and lactic acid bacteria, as the most conventionally used probiotics in aquaculture, numerous studies have focused on other promising alternatives. Diverse species of yeasts and molds belonging to the kingdom ‘Fungi’ have been characterized for their prospective roles in nutrition, immunomodulation, and disease prevention in fish. Bioactive compounds such as manno-oligosaccharides and β-glucans are recognized as fungal postbiotics that improve innate immunity and disease resistance in fish. Actinobacteria are known to possess different hydrolytic enzymes and novel secondary metabolites representing their probiotic attributes. The application of these groups in water quality amelioration has also been explored. Thus, this paper presents an overview of the present status of knowledge pertaining to the effects of yeasts (Candida, Cryptococcus, Debaryomyces, Geotrichum, Leucosporidium, Pichia, Rhodosporidium, Rhodotorula, Saccharomyces, Sporidiobolus, Sporobolomyces, Trichosporon and Yarrowialipolytica), molds (Aspergillus spp.) and actinobacteria (Streptomyces) as probiotics in finfish aquaculture, as well as their occurrence within the gastrointestinal tracts of finfish. Furthermore, probiotic mechanisms, selection criteria, and future perspectives on using fungi and actinobacteria as promising probiotics are discussed. Full article

Onychomycosis, or fungal nail infection, causes not only pain and discomfort but can also have psychological and social consequences for the patient. Treatment of onychomycosis is complicated by the location of the infection under the nail plate, meaning that antifungal molecules must either penetrate the nail or be applied systemically. Currently, available treatments are limited by their poor nail penetration for topical products or their potential toxicity for systemic products. Plant defensins with potent antifungal activity have the potential to be safe and effective treatments for fungal infections in humans. The cystine-stabilized structure of plant defensins makes them stable to the extremes of pH and temperature as well as digestion by proteases. Here, we describe a novel plant defensin, Ppdef1, as a peptide for the treatment of fungal nail infections. Ppdef1 has potent, fungicidal activity against a range of human fungal pathogens, including Candida spp., Cryptococcus spp., dermatophytes, and non-dermatophytic moulds. In particular, Ppdef1 has excellent activity against dermatophytes that infect skin and nails, including the major etiological agent of onychomycosis Trichophyton rubrum. Ppdef1 also penetrates human nails rapidly and efficiently, making it an excellent candidate for a novel topical treatment of onychomycosis. Full article

Cryptococcosis is a systemic mycosis that causes pneumonia and meningoencephalitis. Strongyloidiasis is a chronic gastrointestinal infection caused by parasites of the genus Strongyloides. Cryptococcosis and strongyloidiasis affect the lungs and are more prevalent in the same world regions, i.e., Africa and tropical countries such as Brazil. It is undeniable that those coincidences may lead to the occurrence of coinfections. However, there are no studies focused on the interaction between Cryptococcus spp. and Strongyloides spp. In this work, we aimed to investigate the interaction between Strongyloides venezuelensis (Sv) and Cryptococcus gattii (Cg) in a murine coinfection model. Murine macrophage exposure to Sv antigens reduced their ability to engulf Cg and produce reactive oxygen species, increasing the ability of fungal growth intracellularly. We then infected mice with both pathogens. Sv infection skewed the host’s response to fungal infection, increasing lethality in a murine coinfection model. In addition to increased NO levels and arginase activity, coinfected mice presented a classic Th2 anti-Sv response: eosinophilia, higher levels of alternate activated macrophages (M2), increased concentrations of CCL24 and IL-4, and lower levels of IL-1β. This milieu favored fungal growth in the lungs with prominent translocation to the brain, increasing the host’s tissue damage. In conclusion, our data shows that primary Sv infection promotes Th2 bias of the pulmonary response to Cg-infection and worsens its pathological outcomes. Full article

Candidiasis is one of the most frequent infections worldwide. In this study, the antimicrobial properties of six strains belonging to the Metschnikowia pulcherrima clade were evaluated against twenty Candida and Candida-related Filobasidiella neoformans var. bacillispora (syn. Cryptococcus neoformans) of different origins, employing the agar cross method. The toxic effect of pulcherrimin, a red metabolite that is responsible for the antimicrobial activities of Metschnikowia spp., was evaluated in various experimental models. The results of agar tests showed that the selected M. pulcherrima strains inhibited the growth of the Candida and non-Candida strains. However, inhibition was dependent on the strain and the environment. The presence of peptone, sodium silicate, and a higher incubation temperature decreased the antifungal action of the M. pulcherrima strains. Pulcherrimin showed cytotoxic and antiproliferative activity, with oxidative stress in cells leading to apoptosis. More research is needed on the mechanism of action of pulcherrimin on somatic cells. Full article

Cryptococcus gattii is a pathogenic yeast, member of the C. neoformans/gattii complex. Previous work from our laboratory has established the presence of C. gattii on cacti lesions, providing proof that it can grow in a stressful environment. However, it is not known which part of the cactus the yeast uses for nutrients. The purpose of this research is to determine the ability of C. gattii to grow in different parts of the cactus to assess how the yeast adapts to grow in this unique environment. Cactus media were developed using the outer, inner, and whole cactus from Pilosocereus spp. Cryptcoccus gattii was grown on the different cactus media, along with potato dextrose agar as a control for 24 and 48 h at 30 °C. Compared to the control medium, yeast growth was reduced in all cactus media, while an increase in the capsule development of the yeast grown in the inner part and the whole-cactus media was observed. Interestingly, the yeast produces melanin when grown in the outer membrane medium, which was dependent on laccase, suggesting that the outer membrane may contain a precursor that stimulatates pigment production. To our knowledge, this is the first study addressing these key differences in the growth of C. gattii on different parts of the cactus. Full article

Otomycosis (OM) is a superficial fungal infection of the external auditory canal (EAC) with a worldwide prevalence ranging from 9% to 30%. Commonly, otomycoses are caused by Aspergillus (A.) niger complex and Candida spp. Other causative agents are yeasts of the genera Cryptococcus spp., Rhodotorula spp., Geotrichum candidum, dermatophytes (Trichophyton mentagrophytes), and non-dermatophytes molds (Fusarium spp., Penicillium spp., Mucorales fungi). The widest range of different species causing OM are found in the territories of Iran, India, China, Egypt, Mexico, and Brazil. Fungal infection of the EAC varies from mild to severe forms. It can be acute, subacute, or chronic, and is often unilateral, while the bilateral form is more common in immunocompromised patients. From an epidemiological point of view, tropical and subtropical climates are the most significant risk factor for the development of otomycosis. Other predisposing conditions include clothing habits, EAC hygiene practices, long-term antibiotic therapy, diabetes, and immunodeficiency. Since it is often difficult to distinguish otomycosis from an infection of a different origin, laboratory-based evidence, including standard procedures (microscopy and cultivation), is essential for diagnosis. For the treatment of this superficial fungal infection, there are no official therapeutic guidelines and protocols. However, many antifungals for local application, such as polyene, imidazoles, and allylamines, can be applied, as well as systemic antimycotics (triazoles) in severe forms of infection. Full article

Blood culture systems are a potential alternative to classical cultivation of fungi on mycological media, but there are limited data on the suitability of these systems for culturing other sample types (e.g., sterile body fluids). We conducted a prospective study to evaluate different types of blood culture (BC) bottles for the detection of different fungal species in non-blood samples. A total of 43 fungal isolates were tested for their ability to grow in BD BACTEC Mycosis-IC/F (Mycosis bottles), BD BACTEC Plus Aerobic/F (Aerobic bottles) and BD BACTEC Plus Anaerobic/F (Anaerobic bottles) (Becton Dickinson, East Rutherford, NJ, USA) BC bottles inoculated with spiked samples without the addition of blood or fastidious organism supplement. Time to detection (TTD) was determined for all BC types tested and compared between groups. In general, Mycosis and Aerobic bottles were similar (p > 0.05). The Anaerobic bottles failed to support growth in >86% of cases. The Mycosis bottles were superior in detecting Candida glabrata, Cryptococcus spp. and Aspergillus spp. (p < 0.05). The performance of Mycosis and Aerobic bottles was similar, but if cryptococcosis or aspergillosis is suspected, the use of Mycosis bottles is recommended. Anaerobic bottles are not recommended for fungal detection. Full article