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Objectives: To identify rare fungi from saliva and urine of immunocompromised patients, and apparently healthy controls and to test the susceptibility of the rare fungi to antifungal agents. Patients and methods: One hundred and twenty immunocompromised (cancer, diabetic) patients were enrolled in this study. The clinical specimens were collected from January-July 2011 and included saliva (120) and urine (120) samples, in addition to saliva (60) and urine (60) samples from a control group. The identification process employed direct examination, culture, biochemical tests and API-20 C system test. Susceptibility test to six antifungal agents was prepared for each isolate. Results: Among 110 yeast isolates, only 7 (6.3%) were categorized as unusual yeasts belonging to three genera. Four isolates were Cryptococcus laurantii, one C.neoformans, one Saccharomyces cereviciae, and one isolate was Rhodotorula rubra. All the isolates have various susceptibility to antifungal agents. Conclusion: Many opportunistic fungi are important uncommon pathogens in saliva and urine of immunocompromised patients.

Introduction: Kodamaea ohmeri is a rare, recognized pathogen that has previously been isolated from environmental sources. The patients commonly affected by this yeast include immunocompromised as well as immunocompetent patients having several associated risk factors. Methodology: We report three cases in which K. ohmeri was isolated from blood using Bact T/ALERT. Identification was carried out by MALDI-TOF MS (Vitek-MS, BioMérieux, Marcy-l'Etoile, France) in addition to color characteristics on chromogenic media. The patients had diminished immune response on account of a multitude of comorbidities. Results: K. ohmeri can be misidentified as Candida tropicalis, Candida albicans, or Candida hemolounii by conventional methods; correct and timely identification can be achieved by MALDI-TOF MS. Antifungal susceptibility breakpoints for K. ohmeri are currently not defined. An Echinocandin was added to the treatment regimen of all three of the cases. Conclusions: Identification of K. ohmeri using conventional methods is difficult and unusual yeasts should be carefully observed, especially upon prolonged incubation. [ABSTRACT FROM AUTHOR]

Aim: The increasing recovery rates of unusual yeasts with innate drug resistance make accurate identification crucial for successful therapy and infection control measures. The current study was undertaken to study the utility of CHROMagar Candida (CC) and evaluate an identification algorithm, using germ tube test (GT), CC and a commercial identification kit, API ID 32C. Settings and Design: The prospective study was carried out at a private laboratory in Mumbai, India. Materials and Methods: Identification of 533 yeast and yeast like isolates was carried out using an identification algorithm, comprising of the GT, CC and API tests. Results: CC was useful to detect mixed cultures. We were able to identify 393/533, i.e. 73.7 % of isolates using GT and CC Tests only. This was because C. albicans and C. tropicalis, which can be reliably identified using CC, constituted 75.2 % of the isolates. We were unable to identify 140 isolates, i.e. 26.3 %, using GT and CC tests only and performed additional testing using API ID 32C. CC was not found to be reliable in identifying C. krusei. Conclusion: The diverse identification profile obtained in our study substantiates the need for all diagnostic microbiology laboratories to be better prepared for identifying unusual yeasts. Though GT or CC testing cannot alone suffice for identification of all clinically encountered Candida and yeast-like fungi, use of GT, CC and automated identification systems in a stepwise algorithm can enable the same in a more cost effective manner. [ABSTRACT FROM AUTHOR]

Clinical needs for novel antifungal agents have increased due to the increase of people with a compromised immune system, the appearance of resistant fungi, and infections by unusual yeasts. The search for new molecular targets for antifungals has generated considerable research, especially usingmodern omicsmethods (genomics, genome-wide collections of mutants, and proteomics) and bioinformatics approaches. Recently, micro- and nanoscale approaches have been introduced in antifungal drug discovery. Microfluidic platforms have been developed, since they have a number of advantages compared to traditional multiwell-plate screening, such as low reagent consumption, the manipulation of a large number of cells simultaneously and independently, and ease of integrating numerous analytical standard operations and large-scale integration. Automated high-throughput antifungal drug screening is achievable bymassive parallel processing. Various microfluidic antimicrobial susceptibility testing (AST) methods have been developed, since they can provide the result in a short time-frame, which is necessary for personalized medicine in the clinic. New nanosensors, based on detecting the nanomotions of cells, have been developed to further decrease the time to test antifungal susceptibility to a few minutes. Finally, nanoparticles (especially, silver nanoparticles) that demonstrated antifungal activity are reviewed. [ABSTRACT FROM AUTHOR]

Background and Objectives: Fungal burn wound infections (FBWIs) are one of the most disastrous complications in burn patients. The present study investigated the incidence and the species distribution of fungal agents isolated from burn lesions and reviewed the feautures, underlying conditions, and outcomes of patients. Materials and Methods: The wounds were swabbed and cultured on Sabouraud Dextrose Agar with chloramphenicol medium. Fungal identification was performed using internal transcribed spacer (ITS) and beta-tubulin sequencing. Results: A total of 380 swab specimens were obtained. Of these, 101 patients (26.75 %) were positive in culture. Among the 101 positive cases, most isolates were from males (n= 68, 67.33%) and most of them were over 30 years old. Flame (n=38, 37.63%) was the predominant cause of burns, and previous history of ICU admission (n=35, 34.66%), presence of central venous catheter (n=25, 24.75%), and diabetes mellitus (n=17, 16.83%) were the main underlying conditions. Candida parapsilosis complex (n=36, 35.64%), and Pichia kudriavzevii (C. krusei) (n=8, 7.92%) represent the most commonly isolated species Also, 2 out of 101 patients (2%) died. Conclusion: In the present study, non-albicans Candida species were much higher frequent than C. albicans with most cases associated with Candida parapsilosis complex. [ABSTRACT FROM AUTHOR]

Background: Vulvovaginal candidiasis (VVC) remains one of the most common infections of the female genital tract. This local study was conducted to identify the spectrum of Candida species associated with VVC and recurrent vulvovaginal candidiasis (RVVC) using different phenotypic and genotypic methods and assess their fluconazole susceptibility. Methods: High vaginal swabs were collected from 576 patients with VVC. Swabs were subjected to KOH 10% and cultured on Sabouraud dextrose agar. The species identification of Candida isolates was made using phenotypic methods, including the germ tube test, corn meal agar (CMA), CHROMagar Candida, and PCR-RFLP as the best genotypic methods for confirmation of Candida species in vulvovaginal candidiasis. Fluconazole susceptibility testing was performed using the disk diffusion method. Results: The data were analyzed using the chi-square test. The prevalence of candidiasis was 61%. The socio-demographic profile corresponded to a woman aged 29.14 ± 4.8 years on average, pregnant (77%), diabetic (19%), with hypertension (10%), recurrent (9%), a history of fluconazole use (4%), and under 30 years of age (73%). Vaginal swab cultures yielded Candida growth in 352 cases (61%). Candida albicans was the predominant isolated species (78%), while the most common non-albicans species were C. glabrata (14.7%), C. parapsilosis (4.2%), C. tropicalis (2.8%), and C. krusei (0.56%). Isolates of C. glabrata and C. krusei exhibited the highest rate of Double-Disk Synergy (DDS) resistance among all isolates tested. Conclusion: C. albicans was the most common species. Careful periodical surveillance is needed to identify any changes in the susceptibility patterns to fluconazole with the increased use of this antifungal agent in Sayad Shirazi tertiary care hospital, Iran. [ABSTRACT FROM AUTHOR]

Burn wound infection (BWI) is a major public health problem and the most devastating form of trauma worldwide. Fungi cause BWI as part of monomicrobial or polymicrobial infection, fungaemia, rare aggressive soft tissue infection and as opportunistic infections. The risk factors for acquiring fungal infection in burns include age of burns, total burn size, body surface area (BSA) (30-60%), full thickness burns, inhalational injury, prolonged hospital stay, late surgical excision, open dressing, artificial dermis, central venous catheters, antibiotics, steroid treatment, long-term artificial ventilation, fungal wound colonisation (FWC), hyperglycaemic episodes and other immunosuppressive disorders. Most of the fungal infections are missed owing to lack of clinical awareness and similar presentation as bacterial infection coupled with paucity of mycology laboratories. Expedient diagnosis and treatment of these mycoses can be life-saving as the mortality is otherwise very high. Emergence of resistance in non-albicans Candida spp., unusual yeasts and moulds in fungal BWI, leaves very few fungi susceptible to antifungal drugs, leaving many patients susceptible. There is a need to speciate fungi as far as the topical and systemic antifungal is concerned. Deep tissue biopsy and other relevant samples are processed by standard mycological procedures using direct microscopy, culture and histopathological examination. Patients with FWC should be treated by aggressive surgical debridement and, in the case of fungal wound infection (FWI), in addition to surgical debridement, an intravenous antifungal drug, most commonly amphotericin B or caspofungin, is prescribed followed by de-escalating with voriconazole or itraconazole, or fluconazole depending upon the species or antifungal susceptibility, if available. The propensity for fungal infection increases, the longer the wound is present. Therefore, the development of products to close the wound more rapidly, improvement in topical antifungal therapy with mould activity and implementation of appropriate systemic antifungal therapy guided by antifungal susceptibility may improve the outcome for severely injured burn victims. [ABSTRACT FROM AUTHOR]

During the course of independent studies in Europe, North America, and Africa, seven yeast strains were isolated from insect frass, decaying wood, tree flux, and olive oil sediment. Phylogenetic analysis of two barcoding DNA regions (internal transcribed spacer and the D1/D2 domain of the LSU rRNA gene) revealed that they belong to two closely related undescribed species distinct from all genera in the family Debaryomycetaceae. For reliable taxonomic placement the genomes of four strains of the two novel species and six type strains of closely related species were sequenced. Orthologous genes from 54 genomes of representatives of the Pichiomycetes and 23 outgroup taxa were concatenated to construct a fully supported phylogenetic tree. Consistent with the assumptions, we found that the two new species belong to a novel genus. In addition, the delimitation of the novel species was supported by genetic distance calculations from average nucleotide identity (ANI) and digital DNA:DNA hybridization (dDDH) values. The physiological characterization of the novel species was generally consistent with their genomic content. All strains had two alleles encoding secretory lipase in either two or three copies depending on the species. However, lipolytic activity was detected only in strains with three copies of the secretory lipase gene. Nevertheless, lipolytic activity might be related to their association with the insect gut. Based on these results, formal descriptions of the new genus Rasporella gen. nov. and of two new species Rasporella dianae sp. nov. (holotype UCDFST 68‐643T, MycoBank no.: 850238) and Rasporella oleae sp. nov. (holotype ZIM 2471T, MycoBank no.: 850126) are provided. Take‐away: A new genus within the Debaryomycetaceae family, Rasporella gen. nov. is described along with two new yeast species.The accommodation of the new genus is supported by a phylogenomic analysis involving 77 taxa.Both new species possess genes encoding secretory lipase, but only strains of Rasporella dianae exhibited the ability to degrade olive oil under laboratory conditions.While one of the strains was isolated from olive oil, it was found to be a transient habitat, as most of the other strains were associated with insect frass. [ABSTRACT FROM AUTHOR]

Several non-conventional yeasts are emerging as potential candidate with an ability to produce lignocellulosic ethanol along with other biofuels. Capability to effectively ferment a variety of sugars especially, which are released during lignocellulosic biomass degradation, makes Pichia an organism of choice. By utilizing five carbon sugars along with the six carbon sugars, and generating biofuels with high yields, Pichia is a possible complement with conventional yeasts. Recent research has indicated that these yeasts may have the ability to function as an exoelectrogen, generating electrical energy by extracellular electron transfer. The metabolic pathways and the important products and by-products produced in electrochemical bioreactors by using lignocellulosic hydrolysate and the formation of ethanol and other biofuels are reviewed in the present study. Additionally, it emphasizes Pichia's potential to be used as a flexible biocatalyst for the synthesis of value-added compounds and bioremediation in microbial fuel cells. The article further highlights some gaps and possibilities for future engineering and optimization of Pichia strains for large-scale production. [ABSTRACT FROM AUTHOR]

The production of alcoholic and non-alcoholic rosé wines using Saccharomyces cerevisiae var. boulardii probiotic yeast is described in this study for the first time. Before and after fermentation and distillation, the volatile acidity, lactic, and malic acid levels were evaluated for S. cerevisiae var. boulardii. These contents were compared to those obtained with a standard S. cerevisiae EC-1118 yeast. We measured the levels of gluconic acid and free amino nitrogen in the musts. After fermentation and distillation, yeast viability was assessed as a function of time (0, 15 days, 3 months, and 6 months), both at ambient temperature (25 ± 0.5 °C) and refrigerator temperature (4 ± 0.5 °C). The outcomes revealed that the rosé wine made with S. cerevisiae var. boulardii had the same values and preliminary sensory characteristics as other commercial wines made with S. cerevisiae EC-1118. The S. cerevisiae var. boulardii yeast successfully survived the high alcohol level produced during fermentation and vacuum distillation. The study also revealed that this unique rosé wine retains its probiotic viability for at least 6 months when stored at room temperature or in the refrigerator, making it a suitable candidate for large-scale production where long storage intervals are required by both producers and consumers. [ABSTRACT FROM AUTHOR]

Aim: The increasing recovery rates of unusual yeasts with innate drug resistance make accurate identification crucial for successful therapy and infection control measures. The current study was undertaken to study the utility of CHROMagar Candida (CC) and evaluate an identification algorithm, using germ tube test (GT), CC and a commercial identification kit, API ID 32C. Settings and Design: The prospective study was carried out at a private laboratory in Mumbai, India. Materials and Methods: Identification of 533 yeast and yeast like isolates was carried out using an identification algorithm, comprising of the GT, CC and API tests. Results: CC was useful to detect mixed cultures. We were able to identify 393/533, i.e. 73.7 % of isolates using GT and CC Tests only. This was because C. albicans and C. tropicalis, which can be reliably identified using CC, constituted 75.2 % of the isolates. We were unable to identify 140 isolates, i.e. 26.3 %, using GT and CC tests only and performed additional testing using API ID 32C. CC was not found to be reliable in identifying C. krusei. Conclusion: The diverse identification profile obtained in our study substantiates the need for all diagnostic microbiology laboratories to be better prepared for identifying unusual yeasts. Though GT or CC testing cannot alone suffice for identification of all clinically encountered Candida and yeast-like fungi, use of GT, CC and automated identification systems in a stepwise algorithm can enable the same in a more cost effective manner.

Background: The introduction of MALDI-TOF MS in the clinical microbiology laboratory has modified the approaches for the identification of fungi. Thanks to this tool, it is possible to identify cryptic species, which possess critical susceptibility patterns. Clinical strains were identified using the MicroScan and MALDI-TOF MS systems. Discrepant results from both methods were investigated using ITS rDNA barcoding. Finally, these isolates were also tested for in vitro susceptibility. Results: The percentage of agreement between both methods to 498 yeast isolates was of 93.6% (32 discrepant isolates). The concordance of ITS sequencing with MALDI-TOF MS was higher (99%) than that of MicroScan (94%). Several of these discordant yeasts displayed high MICs for antifungal agents. Conclusions: Our study highlights the need of the MS and molecular approaches such as MALDI-TOF MS and ITS rDNA barcoding for the correct identification of emerging or cryptic yeast species; besides, some of these could be multidrug resistant. This work was the first experience in the implementation of the MALDI-TOF MS technology in Colombia. We found the first uncommon yeasts including Candida auris and we could identify Trichosporon faecalis. Our work highlights a clear necessity of an accurate yeast identification as a much more pertinent technique than the susceptibility profiles, because the most unusual yeasts exhibit resistance profiles to the few available antifungals. [ABSTRACT FROM AUTHOR]

Summary: A growing population of immunosuppressed patients has resulted in increasingly frequent diagnoses of invasive fungal infections, including those caused by unusual yeasts. The incidence of non-albicans species of Candida is increasing compared with that of Candida albicans, and several species, such as Candida glabrata and Candida krusei, may be resistant to azole antifungal therapy. Trichosporon species are the second most common cause of fungaemia in patients with haematological malignant disease and are characterised by resistance to amphotericin and echinocandins and poor prognosis. Rhodotorula species belong to the family Cryptococcaceae, and are a cause of catheter-related fungaemia, sepsis, and invasive disease in severely immunosuppressed patients. An increasing number of sporadic cases of invasive fungal infections by non-neoformans cryptococci have been reported in immunocompromised hosts, especially for patients with advanced HIV infection or cancer who are undergoing transplant. Other uncommon yeasts that can cause invasive disease in severely immunosuppressed patients include Geotrichum, Hansenula, Malassezia, and Saccharomyces. Host immune status is a crucial determinant of the type of invasive fungal infection a patient is at risk for. Diagnosis can be challenging and relies heavily on traditional cultures of blood and other sterile sites, although serum (1,3)-β-D-glucan testing might have an adjunctive role. Although rare yeasts are emerging as opportunistic human pathogens, diagnosis remains challenging and treatment suboptimal. [ABSTRACT FROM AUTHOR]

Purpose of Review: The use of molecular tests to aid the diagnosis of invasive yeast infection, in particular invasive candidosis, has been described for over two decades, yet widespread application is limited, and diagnosis remains heavily dependent on classical microbiology. This article will review developments from the past decade in attempt to build on existing knowledge. It will highlight clinical performance and limitations while reviewing developments on recognized procedures; it will also provide insight into novel approaches incorporated in response to clinical demand (e.g. C. auris and antifungal resistance) or technological advances (e.g. next-generation sequencing). Recent Findings: Limited methodological standardization and, until recently, unavailability of commercial options have hindered the integration of molecular diagnostics for yeasts. The development of certain, novel commercial methods has received considerable evaluation allowing a greater understanding of individual assay performance, but widespread multicentre evaluation of most commercial kits is lacking. The detection of emerging pathogens (e.g. C. auris) has been enhanced by the development of molecular tests. Molecular methods are providing a better understanding of the mycobiome, mechanisms of resistance and epidemiology/phylogeny. Summary: Despite over two decades of use, the incorporation of molecular methods to enhance the diagnosis of yeast infections remains limited to certain specialist centres. While the development of commercial tests will provide stimulus for broader application, further validation and reduced costs are required. Over the same period of time, Aspergillus PCR has become more widely accepted driven by international efforts to standardize methodology; it is critical that yeast PCR follows suit. Next-generation sequencing will provide significant information on the mycobiome, antifungal resistance mechanism and even broad-range detection directly from the specimen, which may be critical for the molecular detection of yeasts other than Candida species, which is currently limited. [ABSTRACT FROM AUTHOR]

Abstract Background The introduction of MALDI-TOF MS in the clinical microbiology laboratory has modified the approaches for the identification of fungi. Thanks to this tool, it is possible to identify cryptic species, which possess critical susceptibility patterns. Clinical strains were identified using the MicroScan and MALDI-TOF MS systems. Discrepant results from both methods were investigated using ITS rDNA barcoding. Finally, these isolates were also tested for in vitro susceptibility. Results The percentage of agreement between both methods to 498 yeast isolates was of 93.6% (32 discrepant isolates). The concordance of ITS sequencing with MALDI-TOF MS was higher (99%) than that of MicroScan (94%). Several of these discordant yeasts displayed high MICs for antifungal agents. Conclusions Our study highlights the need of the MS and molecular approaches such as MALDI-TOF MS and ITS rDNA barcoding for the correct identification of emerging or cryptic yeast species; besides, some of these could be multidrug resistant. This work was the first experience in the implementation of the MALDI-TOF MS technology in Colombia. We found the first uncommon yeasts including Candida auris and we could identify Trichosporon faecalis. Our work highlights a clear necessity of an accurate yeast identification as a much more pertinent technique than the susceptibility profiles, because the most unusual yeasts exhibit resistance profiles to the few available antifungals.

Bloodstream infections (BSI) caused by Candida species are the fourth cause of healthcare associated infections worldwide. Non- albicans Candida species emerged in the last decades as agents of serious diseases. In this study, clinical and microbiological aspects of six patients with BSI due to the Meyerozyma (Candida) guilliermondii species complex from an oncology reference center in Brazil, were evaluated. To describe demographic and clinical characteristics, medical records of the patients were reviewed. Molecular identification of the isolates was performed by ITS1-5.8S-ITS2 region sequencing. Antifungal susceptibility was evaluated by the EUCAST method and the minimal inhibitory concentrations (MIC) assessed according to the epidemiological cutoff values. Virulence associated phenotypes of the isolates were also studied. Ten isolates from the six patients were evaluated. Five of them were identified as Meyerozyma guilliermondii and the others as Meyerozyma caribbica. One patient was infected with two M. caribbica isolates with different genetic backgrounds. High MICs were observed for fluconazole and echinocandins. Non-wild type isolates to voriconazole appeared in one patient previously treated with this azole. Additionally, two patients survived, despite infected with non-wild type strains for fluconazole and treated with this drug. All isolates produced hemolysin, which was not associated with a poor prognosis, and none produced phospholipases. Aspartic proteases, phytase, and esterase were detected in a few isolates. This study shows the reduced antifungal susceptibility and a variable production of virulence-related enzymes by Meyerozyma spp. In addition, it highlights the poor prognosis of neutropenic patients with BSI caused by this emerging species complex. Lay Abstract Our manuscript describes demographic, clinical and microbiological characteristics of patients with bloodstream infection by the Meyerozyma guilliermondii species complex at a reference center in oncology in Brazil. [ABSTRACT FROM AUTHOR]

To determine the dynamic changes of pathogenic yeast prevalence and antifungal susceptibility patterns in tertiary hospitals in China, we analyzed 527 yeast isolates preserved in the Research Center for Medical Mycology at Peking University, Beijing, China, between Jan 2010 and Dec 2019 and correctly identified 19 yeast species by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and ribosomal DNA sequencing. Antifungal susceptibility testing was performed following a Sensititre YeastOne colorimetric microdilution panel with nine clinically available antifungals. The Clinical and Laboratory Standards Institute (CLSI)-approved standard M27-A3 (S4) and newly revised clinical breakpoints or species-specific and method-specific epidemiological cutoff values were used for the interpretation of susceptibility test data. In this study, although Candida albicans was the predominant single species, non- C. albicans species constituted >50% of isolates in 6 out of 10 years, and more rare species were present in the recent 5 years. The non- C. albicans species identified most frequently were Candida parapsilosis sensu stricto , Candida tropicalis , and Candida glabrata. The prevalence of fluconazole and voriconazole resistance in the C. parapsilosis sensu stricto population was <3%, but C. tropicalis exhibited decreased susceptibility to fluconazole (42, 57.5%) and voriconazole (31, 42.5%), and 22 (30.1%) C. tropicalis isolates exhibited wild-type minimum inhibitory concentrations (MICs) to posaconazole. Furthermore, fluconazole and voriconazole cross-resistance prevalence in C. tropicalis was 19 (26.1%). The overall prevalence of fluconazole resistance in the C. glabrata population was 14 (26.9%), and prevalence of isolates exhibiting voriconazole non-wild-type MICs was 33 (63.5%). High-level echinocandin resistance was mainly observed in C. glabrata , and the prevalence rates of isolate resistance to anidulafungin, micafungin, and caspofungin were 5 (9.6%), 5 (9.6%), and 4 (7.7%), respectively. Moreover, one C. glabrata isolate showed multidrug resistant to azoles, echinocandins, and flucytosine. Overall, the 10-year surveillance study showed the increasing prevalence of non- C. albicans species over time; the emergence of azole resistance in C. tropicalis and multidrug resistance in C. glabrata over the years reinforced the need for epidemiological surveillance and monitoring. [ABSTRACT FROM AUTHOR]

Bloodstream infections caused by uncommon or novel fungal species are challenging to identify and treat. We report a series of cases of fungemia due to a rare basidiomycete yeast, Dirkmeia churashimaensis, in neonatal patients in India. Whole-genome sequence typing demonstrated that the patient isolates were genetically indistinguishable, indicating a single-source infection. [ABSTRACT FROM AUTHOR]

Candida auris is an emerging multidrug-resistant yeast that causes serious invasive infections with high mortality. It was first discovered in 2009, and since then, individual cases or outbreaks have been reported from over 20 countries on five continents. Controlling C. auris is challenging for several reasons: (1) it is resistant to multiple classes of antifungals, (2) it can be misidentified as other yeasts by commonly available identification methods, and (3) because of its ability to colonize patients perhaps indefinitely and persist in the healthcare environment, it can spread between patients in healthcare settings. The transmissibility and high levels of antifungal resistance that are characteristic of C. auris set it apart from most other Candida species. A robust response that involves the laboratory, clinicians, and public health agencies is needed to identify and treat infections and prevent transmission. We review the global emergence, biology, challenges with laboratory identification, drug resistance, clinical manifestations, treatment, risk factors for infection, transmission, and control of C. auris. [ABSTRACT FROM AUTHOR]

Introduction Yeast pathogens are emerging agents of nosocomial as well as community-acquired infections and their rapid and accurate identification is crucial for a better management of high-risk patients and for an adequate treatment. Methods We performed a retrospective review of 156 yeast isolates collected during a 17 months' period of regular clinical practice at the Microbiology Department of San Camillo Hospital in Treviso, Italy and analyzed by the traditional culture-based method combined with matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Results Out of all the samples collected MALDI-TOF MS was able to characterize with a MT score ≥1.7 (accurate result at species level) 12 different yeast and yeast-like species from 140 samples: Candida albicans (63.7%), Candida glabrata (13.6%), Saccharomyces cerevisiae (6.5%), Candida parapsilosis (5.7%), Candida tropicalis (2.1%), Candida pararugosa (2.1%), Candida guilliermondii (2.1%), Candida kefyr (1.4%), Candida lusitaniae (0.7%), Candida palmioleophila (0.7%), Geotrichum silvicola (0.7%), Rhodotorula mucilaginosa (0.7%). Susceptibility testing toward seven common antifungal agents showed a characteristic MIC distribution of C. albicans isolates for echinocandins: particularly we noticed that 72% and 46% of C. albicans showed an MIC value close to clinical breakpoint as defined by EUCAST, respectively for anidulafungin and micafungin. Conclusion Accurate identification of microorganisms and the study of their antifungal susceptibility allow to understand the epidemiology of a particular area, permitting the choice of the most appropriate early antifungal treatment. [ABSTRACT FROM AUTHOR]

Candida auris is a rapidly emerging pathogen and is able to cause severe infections with high mortality rates. It is frequently misidentified in most clinical laboratories, thus requiring more specialized identification techniques. Furthermore, several clinical isolates have been found to be multidrug resistant and there is evidence of nosocomial transmission in outbreak fashion. Appropriate infection control measures will play a major role in controlling the management and spread of this pathogen. Unfortunately, there are very few data available on the effectiveness of disinfectants against C. auris. Chlorine-based products appear to be the most effective for environmental surface disinfection. Other disinfectants, although less effective than chlorine-based products, may have a role as adjunctive disinfectants. A cleaning protocol will also need to be established as the use of disinfectants alone may not be sufficient for maximal decontamination of patient care areas. Furthermore, there are fewer data on the effectiveness of antiseptics against C. auris for patient decolonization and hand hygiene for healthcare personnel. Chlorhexidine gluconate has shown some efficacy in in vitro studies but there are reports of patients with persistent colonization despite twice daily body washes with this disinfectant. Hand hygiene using soap and water, with or without chlorhexidine gluconate, may require the subsequent use of alcohol-based hand sanitizer for maximal disinfection. Further studies will be needed to validate the currently studied disinfectants for use in real-world settings. [ABSTRACT FROM AUTHOR]

Clinical needs for novel antifungal agents have increased due to the increase of people with a compromised immune system, the appearance of resistant fungi, and infections by unusual yeasts. The search for new molecular targets for antifungals has generated considerable research, especially using modern omics methods (genomics, genome-wide collections of mutants, and proteomics) and bioinformatics approaches. Recently, micro- and nanoscale approaches have been introduced in antifungal drug discovery. Microfluidic platforms have been developed, since they have a number of advantages compared to traditional multiwell-plate screening, such as low reagent consumption, the manipulation of a large number of cells simultaneously and independently, and ease of integrating numerous analytical standard operations and large-scale integration. Automated high-throughput antifungal drug screening is achievable by massive parallel processing. Various microfluidic antimicrobial susceptibility testing (AST) methods have been developed, since they can provide the result in a short time-frame, which is necessary for personalized medicine in the clinic. New nanosensors, based on detecting the nanomotions of cells, have been developed to further decrease the time to test antifungal susceptibility to a few minutes. Finally, nanoparticles (especially, silver nanoparticles) that demonstrated antifungal activity are reviewed.

Candida wangnamkhiaoensis is a species clustered under the Hyphopichia clade has not ever been isolated from any clinical specimens. To the best of our knowledge, this is the first report of C. wangnamkhiaoensis associated with fungaemia in immunocompromised paediatric patient. The isolate was assigned a strain name as UZ1679/14, in which the identification was confirmed by a polymerase chain reaction-sequencing of the internal transcribed spacer ( ITS) and large subunit ( LSU) regions of the rRNA gene. Antifungal susceptibility pattern showed that the isolate was sensitive to anidulafungin, caspofungin, fluconazole and voriconazole. The patient clinically improved after the antifungal treatment with caspofungin. [ABSTRACT FROM AUTHOR]

Burn wound infection (BWI) is a major public health problem and the most devastating form of trauma worldwide. Fungi cause BWI as part of monomicrobial or polymicrobial infection, fungaemia, rare aggressive soft tissue infection and as opportunistic infections. The risk factors for acquiring fungal infection in burns include age of burns, total burn size, body surface area (BSA) (30–60%), full thickness burns, inhalational injury, prolonged hospital stay, late surgical excision, open dressing, artificial dermis, central venous catheters, antibiotics, steroid treatment, long-term artificial ventilation, fungal wound colonisation (FWC), hyperglycaemic episodes and other immunosuppressive disorders. Most of the fungal infections are missed owing to lack of clinical awareness and similar presentation as bacterial infection coupled with paucity of mycology laboratories. Expedient diagnosis and treatment of these mycoses can be life-saving as the mortality is otherwise very high. Emergence of resistance in non-albicans Candida spp., unusual yeasts and moulds in fungal BWI, leaves very few fungi susceptible to antifungal drugs, leaving many patients susceptible. There is a need to speciate fungi as far as the topical and systemic antifungal is concerned. Deep tissue biopsy and other relevant samples are processed by standard mycological procedures using direct microscopy, culture and histopathological examination. Patients with FWC should be treated by aggressive surgical debridement and, in the case of fungal wound infection (FWI), in addition to surgical debridement, an intravenous antifungal drug, most commonly amphotericin B or caspofungin, is prescribed followed by de-escalating with voriconazole or itraconazole, or fluconazole depending upon the species or antifungal susceptibility, if available. The propensity for fungal infection increases, the longer the wound is present. Therefore, the development of products to close the wound more rapidly, improvement in topical antifungal therapy with mould activity and implementation of appropriate systemic antifungal therapy guided by antifungal susceptibility may improve the outcome for severely injured burn victims.

Purpose The isolation of yeast species other than Candida albicans from the oral mucosa has been increasing in frequency, suggesting that those may constitute emerging potential oral colonizers. The purpose of this work was to determine whether yeast species other than C. albicans are associated with factors related to wearing of dental prostheses. Materials and Methods tRNA-PCR fingerprinting and sequencing of the 26S rDNA D1/D2 domain were used to identify all yeasts isolated from CHROMagar™ Candida cultures of oral swabs collected from 178 patients. Results Besides C. albicans, 13 other species were identified, corresponding to 34% of the yeast isolates. The majority of the non- C. albicans species were not detected as single colonizers but rather in co-colonization with one or two other yeasts, often with C. albicans. No significant associations were found with non- C. albicans species. On the contrary, the best-fitted logistic regression model predicts that either wearing a denture (adjusted odds = 4.6) or insufficient oral hygiene (adjusted odds = 2.3) are risks for colonization by yeast, in general. Conclusions The colonization with non- C. albicans species and co-colonization were not independently associated with any of the analyzed host-related factors. In particular, neither wearing a removable denture nor being elderly were significant predictors. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics which include the antifungal activity of isavuconazole to Madurella mycetomatis, antibacterial activity of bifonazole to Corynebacterium minutissimum, and antibiofilm activity of Allium sativum extract to biofilm formed from Candida sp.

Summary The current study was conducted to know the incidence, predisposing factors, spectrum, clinical profile and antifungal susceptibility (AFS) of fungal wound infection (FWI) in burn patients. Of a total of 71 patients, 20 (28.2%) emerged with the diagnosis of FWI. Fungal pathogens in this study were Candida tropicalis (14%), Candida parapsilosis (5.6%), Aspergillus niger (2.8%) and one each of Candida albicans (1.4%), Candida glabrata (1.4%), Syncephalestrum (1.4%) and Fusarium solani (1.4%). All patients with mould infections expired before the mycological culture results could be conveyed to clinicians. Of the yeasts isolated in the study, one each of C. tropicalis and C. albicans showed cross-resistance to azoles. All the moulds were susceptible to amphotericin B. This study depicted that fungal invasion is associated with a high mortality, burn size 30-60% and high incidence of inhalational injury. Fungal invasion was detected on an average of 14 days after injury. Association of use of four classes of drugs - aminoglycosides, imipenem, vancomycin and third generation cephalosporins and use of total parenteral nutrition was observed. Expedient laboratory diagnosis of FWI and appropriate systemic antifungal therapy guided by AFS may improve outcome for severely injured burn victims. [ABSTRACT FROM AUTHOR]

We report 5 cases of disseminated infection caused by Blastoschizomyces capitatus yeast in central Switzerland. The emergence of this yeast in an area in which it is not known to be endemic should alert clinicians caring for immunocompromised patients outside the Mediterranean region to consider infections caused by unfamiliar fungal pathogens. [ABSTRACT FROM AUTHOR]

Introduction: Identification of yeast isolated from clinical specimens to the species level has become increasingly important. Ever-increasing numbers of immuno-suppressed patients, a widening range of recognized pathogens, and the discovery of resistance to antifungal drugs are contributing factors to this necessity. Material and methods: A total of 487 yeast strains were studied for the primary isolation and presumptive identification, directly from clinical specimen. Efficacy of CHROMagar Candida has been evaluated with conventional methods including morphology on Corn meal-tween 80 agar and biochemical methods by using API 20 C AUX. Results: The result of this study shows that CHROMagar Candida can easily identify three species of Candida on the basis of colonial color and morphology, and accurately differentiate between them i.e. Candida albicans, Candida tropicalis, and Candida krusei. The specificity and sensitivity of CHROMagar Candida for C. albicans calculated as 99%, for C. tropicalis calculated as 98%, and C. krusei it is 100%. Conclusion: The data presented supports the use of CHROMagar Candida for the rapid identification of Candida species directly from clinical specimens in resource-limited settings, which could be very helpful in developing appropriate therapeutic strategy and management of patients. [ABSTRACT FROM AUTHOR]

Since the first report in 1998, 10 cases of Pichia ohmeri infection have been reported in the literature. Here we present two new cases of P. ohmeri infection in the paediatric age group. The first case was an 8-month-old male infant, who was admitted with fever, convulsions and altered consciousness. Conservative therapy was started with a presumptive diagnosis of encephalitis. The patient failed to respond to the given treatments and died on the 21st day of hospitalisation. The second case was a 10-year-old male with B-cell acute lymphoblastic leukaemia. He was hospitalised with neutropenic fever. He was discharged after 3 weeks of therapy. In both cases P. ohmeri was identified in blood samples. Growing evidence indicates that P. ohmeri should be added to the lengthening list of opportunistic fungal pathogens that can cause infection in all ages, including infants, and particularly in those who are immunocompromised. [ABSTRACT FROM AUTHOR]

The insertion or implantation of foreign bodies has become an indispensable part in almost all fields of medicine. However, medical devices are associated with a definitive risk of bacterial and fungal infections. Foreign body-related infections (FBRIs), particularly catheter-related infections, significantly contribute to the increasing problem of nosocomial infections. While a variety of micro-organisms may be involved as pathogens, staphylococci account for the majority of FBRIs. Their ability to adhere to materials and to promote formation of a biofilm is the most important feature of their pathogenicity. This biofilm on the surface of colonised foreign bodies is regarded as the biological correlative for the clinical experience with FBRI, that is, that the host defence mechanisms often seem to be unable to handle the infection and, in particular, to eliminate the micro-organisms from the infected device. Since antibacterial chemotherapy is also frequently not able to cure these infections despite the use of antibacterials with proven in vitro activity, removal of implanted devices is often inevitable and has been standard clinical practice. However, in specific circumstances, such as infections of implanted medical devices with coagulase-negative staphylococci, a trial of salvage of the device may be justified. All FBRIs should be treated with antibacterials to which the pathogens have been shown to be susceptible. In addition to systemic antibacterial therapy, an intraluminal application of antibacterial agents, referred to as the ‘antibiotic-lock’ technique, should be considered to circumvent the need for removal, especially in patients with implanted long-term catheters. To reduce the incidence of intravascular catheter-related bloodstream infections, specific guidelines comprising both technological and nontechnological strategies for prevention have been established. Quality assurance, continuing education, choice of the catheter insertion site, hand hygiene and aseptic techniques are aspects of particular interest. Furthermore, all steps in the pathogenesis of biofilm formation may represent targets against which prevention strategies may be directed. Alteration of the foreign body material surface may lead to a change in specific and nonspecific interactions with micro-organisms and, thus, to a reduced microbial adherence. Medical devices made out of a material that would be antiadhesive or at least colonisation resistant would be the most suitable candidates to avoid colonisation and subsequent infection. Another concept for the prevention of FBRIs involves the impregnation of devices with various substances such as antibacterials, antiseptics and/or metals. Finally, further studies are needed to translate the knowledge on the mechanisms of biofilm formation into applicable therapeutic and preventive strategies. [ABSTRACT FROM AUTHOR]

Zygosaccharomyces kombuchaensis was recently discovered in the ‘tea fungus’ used to make fermented tea. Z. kombuchaensis was shown by ribosomal DNA sequencing to be a novel species, and a close relative of Zygosaccharomyces lentus, from which it could not be distinguished by conventional physiological tests. Z. lentus was originally established as a new taxon by growth at 4°C, sensitivity for heat and oxidative stress, and lack of growth in aerobic shaken culture at temperatures above 25°C. Subsequent analysis of Z. kombuchaensis reveals that this species shares these unusual characteristics, confirming its close genealogical relationship to Z. lentus. Detailed physiological data from a number of Z. kombuchaensis and Z. lentus strains clearly demonstrate that these two species can in fact be distinguished from one another based on their differing resistance/sensitivity to the food preservatives benzoic acid and sorbic acid. The spoilage yeasts Zygosaccharomyces bailii and Z. lentus are resistant to both acetic acid and sorbic acid, whereas Z. kombuchaensis is resistant to acetic acid but sensitive to sorbic acid. This would indicate that Z. kombuchaensis strains lack the mechanism for resistance to sorbic acid, but possess the means of resistance to acetic acid. This observation would therefore suggest that these two resistance mechanisms are different, and that in all probability acetic and sorbic acids inhibit yeast growth by different modes of action. Z. kombuchaensis strains were also sensitive to benzoic acid, again suggesting inhibition dissimilar from that to acetic acid. [ABSTRACT FROM AUTHOR]

The first step in the infection of fungal pathogens in humans is the adhesion of the pathogen to host tissue cells or abiotic surfaces such as catheters and implants. One of the main players involved in this are the expressed cell wall adhesins. Here, we review the Flo adhesin family and their involvement in the adhesion of these yeasts during human infections. Firstly, we redefined the Flo adhesin family based on the domain architectures that are present in the Flo adhesins and their functions, and set up a new classification of Flo adhesins. Next, the structure, function, and adhesion mechanisms of the Flo adhesins whose structure has been solved are discussed in detail. Finally, we identified from Pfam database datamining yeasts that could express Flo adhesins and are encountered in human infections and their adhesin architectures. These yeasts are discussed in relation to their adhesion characteristics and involvement in infections. [ABSTRACT FROM AUTHOR]

The number of fungal species reported to cause disease in man is increasing rapidly. Very few of these fungi are capable of infecting a normal host. Important progress has been achieved in an understanding of fungal pathogenicity including the mechanisms of adherence to host tissues, penetration of tissues, multiplication within the host, and the interaction of fungal cells with host effector cells. In addition to the increase in infections by opportunistic and pathogenic fungi in compromised patients, caused by Candida spp., Aspergillus spp., Cryptococcus neoformans, Histoplasma capsulation and Coccidioides immitis, many fungi that occur as saprophytes in the environment and which had previously been considered to be nonpathogenic are now being encountered as causes of human infection. The advent of these unusual infections has led to reappraisal of the diagnostic tests involved in the investigation of fungal infections and has had important implications for the choice of treatment. Many of these fungi have a similar tissue appearance and the organisms must be isolated and identified to ensure that the most appropriate treatment is given. [ABSTRACT FROM PUBLISHER]