Emerging infections caused by non-Aspergillus filamentous fungi

Dematiaceous Molds

Dematiaceous molds are darkly pigmented environmental molds found worldwide, especially prevalent in tropical and subtropical regions. Common genera include Bipolaris, Cladophialophora, Exophiala, and Alternaria. They cause disease in both immunocompetent and immunocompromised individuals, presenting as cutaneous infections, allergic sinusitis, pneumonia, and, rarely, disseminated infections. Contaminated medical products have also led to fungal meningitis outbreaks. Treatment typically involves itraconazole, voriconazole, or posaconazole, along with source control and reduction in immunosuppression, if possible. Newer antifungals may have a role in treatment. Mortality is high in disseminated disease, especially with Lomentospora prolificans in immunocompromised individuals, prompting global efforts to improve diagnostics and treatments.

Meeting the Therapeutic Challenges of Emergent and Rare Invasive Fungal Diseases Through Novel Clinical Trial Designs

Treatments for emerging and rare invasive fungal diseases (IFDs) represent a critical unmet medical need. For IFDs that occur less frequently than invasive aspergillosis, such as mucormycosis, hyalohyphomycosis, and phaeohyphomycosis, randomized controlled clinical trials are impractical and unlikely to meet urgent public health needs. Understanding regulatory approaches for approval of drugs for rare cancers and rare metabolic diseases could help meet the challenges of studying drugs for rare IFDs. A single-arm, controlled clinical trial with a high-quality external control(s), with confirmatory evidence from nonclinical studies, including pharmacokinetic/pharmacodynamic data in predictive animal models of the disease may support findings of effectiveness of new drugs and biologics. Control populations may include historical controls from published literature, patient registries, and/or contemporaneous external control groups. Continuous engagement among clinicians, industrial sponsors, and regulatory agencies to develop consensus on trial design and innovative development pathways for emergent and rare invasive fungal diseases is important.

Diagnosis of pulmonary Scedosporium apiospermum infection from bronchoalveolar lavage fluid by metagenomic next-generation sequencing in an immunocompetent female patient with normal lung structure: a case report and literature review

BACKGROUND

Scedosporium apiospermum (S. apiospermum) belongs to the asexual form of Pseudallescheria boydii and is widely distributed in various environments. S. apiospermum is the most common cause of pulmonary infection; however, invasive diseases are usually limited to patients with immunodeficiency.

CASE PRESENTATION

A 54-year-old Chinese non-smoker female patient with normal lung structure and function was diagnosed with pulmonary S. apiospermum infection by metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid (BALF). The patient was admitted to the hospital after experiencing intermittent right chest pain for 8 months. Chest computed tomography revealed a thick-walled cavity in the upper lobe of the right lung with mild soft tissue enhancement. S. apiospermum was detected by the mNGS of BALF, and DNA sequencing reads were 426. Following treatment with voriconazole (300 mg q12h d1; 200 mg q12h d2-d20), there was no improvement in chest imaging, and a thoracoscopic right upper lobectomy was performed. Postoperative pathological results observed silver staining and PAS-positive oval spores in the alveolar septum, bronchiolar wall, and alveolar cavity, and fungal infection was considered. The patient's symptoms improved; the patient continued voriconazole for 2 months after surgery. No signs of radiological progression or recurrence were observed at the 10-month postoperative follow-up.

CONCLUSION

This case report indicates that S. apiospermum infection can occur in immunocompetent individuals and that the mNGS of BALF can assist in its diagnosis and treatment. Additionally, the combined therapy of antifungal drugs and surgery exhibits a potent effect on the disease.

Practical issues related to non-Aspergillus invasive mold infections

Infection by non-Aspergillus molds has been increasingly reported. The management of such infections is challenging both for diagnosis and treatment, including the need of well-trained mycologists to properly identify rare fungi, difficulties in distinguishing between contamination, colonization and infection, the lack of randomized studies comparing different drugs or regimens, poor activity of available antifungal agents, lack of correlation between in vitro antifungal susceptibility tests and clinical outcome, and poor prognosis. Mucormycosis and fusariosis are the most frequent non-Aspergillus mold infections. Mucormycosis occurs more frequently in four major groups of patients: solid organ transplant recipients, patients with hematologic malignancies receiving chemotherapy or hematopoietic cell transplantation, diabetic patients, and immunocompetent individuals who suffer various types of skin and soft tissue trauma. Invasive fusariosis occurs almost exclusively in patients with hematologic malignancies. In this review we discuss practical issues related to the management of these and other non-Aspergillus mold infections.

Unusual manifestation of pulmonary Verruconis gallopava infection with synchronous reactive pericardial effusion in a non-transplanted patient

Verruconis gallopava is an emerging causative agent in solid organ transplant patients, increasing in prevalence both in non-transplanted patients and also in immunocompetent ones, albeit rarely. In this case report, we describe an unusual V. gallopava infection in a patient with steroid-dependent autoimmune haemolytic anaemia. The chest CT scan revealed a mass-like consolidation in the superior segment of the right lower lobe, and bronchoscopic examination confirmed V. gallopava from bronchoalveolar lavage. The histopathology showed non-necrotising granulomatous inflammation concurrent with septate-pigmented hyphae, which is compatible with dematiaceous fungi. After 3 weeks of posaconazole treatment, the patient developed a new pericardial effusion. Further investigations, including culture, cytology and histopathology, yielded negative results, leading to suspicion of reactive pericardial effusion associated with V. gallopava pulmonary infection. The patient received antifungal therapy for 9 months, after which a follow-up chest CT scan showed complete resolution of consolidation and pericardial effusion.

Attention-Guided Transfer Learning for Identification of Filamentous Fungi Encountered in the Clinical Laboratory

This study addresses the challenge of accurately identifying filamentous fungi in medical laboratories using transfer learning with convolutional neural networks (CNNs). The study uses microscopic images from touch-tape slides with lactophenol cotton blue staining, the most common method in clinical settings, to classify fungal genera and identify Aspergillus species. The training and test data sets included 4,108 images with representative microscopic morphology for each genus, and a soft attention mechanism was incorporated to enhance classification accuracy. As a result, the study achieved an overall classification accuracy of 94.9% for four frequently encountered genera and 84.5% for Aspergillus species. One of the distinct features is the involvement of medical technologists in developing a model that seamlessly integrates into routine workflows. In addition, the study highlights the potential of merging advanced technology with medical laboratory practices to diagnose filamentous fungi accurately and efficiently. IMPORTANCE This study utilizes transfer learning with CNNs to classify fungal genera and identify Aspergillus species using microscopic images from touch-tape preparation and lactophenol cotton blue staining. The training and test data sets included 4,108 images with representative microscopic morphology for each genus, and a soft attention mechanism was incorporated to enhance classification accuracy. As a result, the study achieved an overall classification accuracy of 94.9% for four frequently encountered genera and 84.5% for Aspergillus species. One of the distinct features is the involvement of medical technologists in developing a model that seamlessly integrates into routine workflows. In addition, the study highlights the potential of merging advanced technology with medical laboratory practices to diagnose filamentous fungi accurately and efficiently.

Antifungal Development and the Urgency of Minimizing the Impact of Fungal Diseases on Public Health

Fungal infections are a major public health problem resulting from the lack of public policies addressing these diseases, toxic and/or expensive therapeutic tools, scarce diagnostic tests, and unavailable vaccines. In this Perspective, we discuss the need for novel antifungal alternatives, highlighting new initiatives based on drug repurposing and the development of novel antifungals.

The need for evolution in the management of febrile neutropenia in pediatric cancer: TRIIO KIDS update

New treatments have increased the life expectancy of pediatric patients diagnosed with malignant hematological diseases, often at the cost of protracting their immunocompromised state in the form of prolonged neutropenia. This neutropenic state favors the development of bacterial and fungal infections. Moreover, recent years have seen a series of changes in the epidemiology of fungal and Clostridium infections. These changes necessitate adaptations to the management of pediatric patients with febrile neutropenia, who are at risk of further increases in already high rates of morbidity and mortality. This article discusses the current bases for the management of febrile neutropenia and associated emerging fungal infections, as well as the epidemiology, diagnosis, and treatment of Clostridioides difficile in pediatric patients diagnosed with malignant hematological diseases.

Trichoderma after crossing kingdoms: infections in human populations

Trichoderma is a saprophytic fungus that is used worldwide as a biocontrol and biofertilizer agent. Although considered nonpathogenic until recently, reports of human infections produced by members of the Trichoderma genus are increasing. Numerous sources of infection were proposed based upon patient data and phylogenetic analysis, including air, agriculture, and healthcare facilities, but the deficit of knowledge concerning Trichoderma infections makes patient treatment difficult. These issues are compounded by isolates that present profiles which exhibit high minimum inhibitory concentration values to available antifungal drugs. The aim of this review is to present the global distribution and sources of infections that affect both immunocompetent and immunocompromised hosts, clinical features, therapeutic strategies that are used to treat patients, as well as highlighting treatments with the best responses. In addition, the antifungal susceptibility profiles of Trichoderma isolates that have emerged in recent decades were examined and which antifungal drugs need to be further evaluated as potential candidates to treat Trichoderma infections are also indicated.

Molecular epidemiology of clinical filamentous fungi in Qatar beyond Aspergillus and Fusarium with notes on the rare species

Due to an increasing number of patients at risk (i.e., those with a highly compromised immune system and/or receiving aggressive chemotherapy treatment), invasive fungal infections (IFI) are increasingly being reported and associated with high mortality rates. Aspergillus spp., particularly A. fumigatus, is the major cause of IFI caused by filamentous fungi around the world followed by Fusarium spp., however, other fungi are emerging as human pathogens. The aim of this study was to explore the epidemiology and prevalence of the non-Aspergillus and non-Fusarium filamentous fungi in human clinical samples over an 11-year period in Qatar using molecular techniques. We recovered 53 filamentous fungal isolates from patients with various clinical conditions. Most patients were males (75.5%), 9.4% were immunocompromised, 20.7% had IFI, and 11.3% died within 30 days of diagnosis. The fungal isolates were recovered from a variety of clinical samples, including the nasal cavity, wounds, respiratory samples, body fluids, eye, ear, tissue, abscess, and blood specimens. Among the fungi isolated, 49% were dematiaceous fungi, followed by Mucorales (30%), with the latter group Mucorales being the major cause of IFI (5/11, 45.5%). The current study highlights the epidemiology and spectrum of filamentous fungal genera, other than Aspergillus and Fusarium, recovered from human clinical samples in Qatar, excluding superficial infections, which can aid in the surveillance of uncommon and emerging mycoses.

Non-Aspergillus mould lung infections

Non-Aspergillus filamentous fungi causing invasive mould infections have increased over the last years due to the widespread use of anti-Aspergillus prophylaxis and increased complexity and survival of immunosuppressed patients. In the few studies that have reported on invasive mould infection epidemiology, Mucorales are the most frequently isolated group, followed by either Fusarium spp. or Scedosporium spp. The overall incidence is low, but related mortality is exceedingly high. Patients with haematological malignancies and haematopoietic stem cell transplant recipients comprise the classical groups at risk of infection for non-Aspergillus moulds due to profound immunosuppression and the vast use of anti-Aspergillus prophylaxis. Solid organ transplant recipients also face a high risk, especially those receiving lung transplants, due to direct exposure of the graft to mould spores with altered mechanical and immunological elimination, and intense, associated immunosuppression. Diagnosing non-Aspergillus moulds is challenging due to unspecific symptoms and radiological findings, lack of specific biomarkers, and low sensitivity of cultures. However, the advent of molecular techniques may prove helpful. Mucormycosis, fusariosis and scedosporiosis hold some differences regarding clinical paradigmatic presentations and preferred antifungal therapy. Surgery might be an option, especially in mucormycosis. Finally, various promising strategies to restore or enhance the host immune response are under current evaluation.

Efficacy of Propolis Gel on Mature Biofilm Formed by Neocosmospora keratoplastica Isolated from Onychomycosis

This article describes Neocosmospora keratoplastica as an etiological onychomycosis agent. Ex vivo studies were initially performed to demonstrate the ability of this species to grow and form a well-organized characteristic biofilm on sterilized healthy nails. Based on the history of excellent results, both for antifungal and antibiofilm, of propolis resin gum, we evaluated its activity using artificially formed biofilm. In vitro, the minimal biofilm eradication concentration of the propolis extract (PE) was 375 µg of total polyphenol content (TPC) per mL, while for the propolis gel (PG) it was 450 µg of TPC per mL. In biofilm exposed to the propolis products, a decrease in hyphae and conidia was evident, accompanied by a disorganization of the extracellular matrix. Additionally, this low concentration of PE was able to significantly reduce the number of colony-forming units and the metabolic activity. Furthermore, the treatment of a 15-year nail infection due to N. keratoplastica was carried out exclusively using a topical treatment with a gel containing propolis (30%) with a daily dosage. This treatment achieved complete remission of the onychomycosis in 12 months. It is important to point out that some inconveniences previously reported by other patients treated with propolis extract were eliminated, increasing adherence to treatment.

Nail Changes in People Living with Human Immunodeficiency Virus: Observational and Cross-Sectional Study in a Third-Level Hospital

Introduction

Nail changes in people living with human immunodeficiency virus (HIV) have been scarcely reported. The aim of this study was to establish the frequency and characteristics of nail alterations observed in adults with HIV infection in a third-level hospital in Mexico.

Method

Observational and cross-sectional study carried out in 205 patients receiving care at the HIV/AIDS Clinic of the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ) in Mexico City. We performed a nail and iconographic assessment of both hands and toenails. We collected information of demographic and clinical variables, as well as drugs use, and antiretroviral treatment used by the participants through a questionnaire and from medical records. We performed direct cytological examinations and nail mycological cultures in participants with symptoms of onychomycosis.

Results

The participants were predominantly male patients (91.2%), with a mean age of 41 (range 21-78) years, under antiretroviral therapy (91.2%), with a suppressed viral load (78.5%) and mean CD4+ lymphocyte count of 379.5 (range 20-1,162) cells/μL. Fitzpatrick's IV phototype was prevailing in the studied population (70%). Nail changes were documented in 72.2% of the patients; being pigmentary changes (37.1%) and trauma (30.7%) the most frequent. Onychomycosis was observed in 26.3%; with total dystrophic onychomycosis as the most frequent clinical variant (68.5%). We obtained fungal isolates in 59.3% of participants and Candida parapsilosis was the most frequent of these (37.5%).

Conclusions

We observed a high prevalence of nail changes with very diverse etiology, as well as a variety of nondermatophytic yeasts and molds isolates associated with cases with onychomycosis. These findings reinforce and confirm the need for routine nail examination and stress the importance of medical personnel working with people living with HIV to have broad knowledge of nail pathology.

Rapid Identification of Four Fusarium spp. Complex by High-Resolution Melting Curve Analysis and their Antifungal Susceptibility Profiles

Fusarium species are globally distributed filamentous ascomycete fungi that are frequently reported as plant pathogens and opportunistic human pathogens, leading to yield loss of crops, mycotoxin contamination of food and feed products as well as damage to human and livestock. Human infections of Fusarium spp. are difficult to treat due to broad antifungal resistance by members of this genus. Their role as disease-causing agents in crops and humans suggests a need for antifungal resistance profiles as well as a simple, rapid, and cost effective identification method. Fusarium strains were isolated from food and clinical samples. High-resolution melting curve (HRM) analysis was performed using specific primers targeting internal transcribed spacer (ITS) region, followed with evaluation of specificity and sensitivity. The antifungal susceptibility of four Fusarium species was studied using the Sensititre YeastOne method. HRM analysis revealed reproducible, unimodal melting profiles specific to each of the four Fusarium strains, while no amplification of the negative controls. The minimum detection limits were 100-120 copies based on a 2 µl volume of template. Clear susceptibility differences were observed against antifungal agents by different Fusarium isolates, with amphotericin B and voriconazole displayed strongest antifungal effects to all the tested strains. We developed a simple, rapid, and low-cost qPCR-HRM method for identification of four Fusarium spp. (F. oxysporum, F. lateritium, F. fujikuroi, and F. solani). The antifungal susceptibility profiles supplied antifungal information of foodborne and clinical Fusarium spp. and provided guidance for clinical treatment of human infections.

A bacterial endosymbiont of the fungus Rhizopus microsporus drives phagocyte evasion and opportunistic virulence

Opportunistic infections by environmental fungi are a growing clinical problem, driven by an increasing population of people with immunocompromising conditions. Spores of the Mucorales order are ubiquitous in the environment but can also cause acute invasive infections in humans through germination and evasion of the mammalian host immune system. How they achieve this and the evolutionary drivers underlying the acquisition of virulence mechanisms are poorly understood. Here, we show that a clinical isolate of Rhizopus microsporus contains a Ralstonia pickettii bacterial endosymbiont required for virulence in both zebrafish and mice and that this endosymbiosis enables the secretion of factors that potently suppress growth of the soil amoeba Dictyostelium discoideum, as well as their ability to engulf and kill other microbes. As amoebas are natural environmental predators of both bacteria and fungi, we propose that this tri-kingdom interaction contributes to establishing endosymbiosis and the acquisition of anti-phagocyte activity. Importantly, we show that this activity also protects fungal spores from phagocytosis and clearance by human macrophages, and endosymbiont removal renders the fungal spores avirulent in vivo. Together, these findings describe a new role for a bacterial endosymbiont in Rhizopus microsporus pathogenesis in animals and suggest a mechanism of virulence acquisition through environmental interactions with amoebas.

Work clothes as a vector for microorganisms: Accumulation, transport, and resuspension of microorganisms as demonstrated for waste collection workers

Work clothes may act as a vector for the transport of microorganisms leading to second-hand exposure; however, this has not been studied in work environments. We investigated whether microorganisms accumulate on workers' clothes in environments with elevated microbial exposures, and whether they are transported with the clothes and subsequently resuspended to the air. To study this, we selected waste collection workers and potential transport of bacteria and fungi to waste truck cabs via clothes, and compared the microbial communities within truck cabs, in waste collection workers' personal exposure, and on clean T-shirts worn by the workers. Microbial communities were also investigated for the presence of potentially harmful microorganisms. Results showed that microorganisms accumulated in large quantities (GM = 3.69 × 10⁵ CFU/m²/h for bacteria, GM = 8.29 × 10⁴ CFU/m²/h for fungi) on workers' clothes. The concentrations and species composition of airborne fungi in the truck cabs correlated significantly with the accumulation and composition of fungi on clothes and correlated to concentrations (a trend) and species composition of their personal exposures. The same patterns were not found for bacteria, indicating that work clothes to a lesser degree act as a vector for bacteria under waste collection workers' working conditions compared to fungi. Several pathogenic or allergenic microorganisms were present, e.g.: Klebsiella oxytoca, K. pneumoniae, Proteus mirabilis, Providencia rettgeri, Pseudomonas aeruginosa, and Aspergillus fumigatus, A. glaucus, A. nidulans, A. niger, and various Penicillium species. The potential 'take-home' exposure to these microorganisms are of most concern for immunocompromised or atopic individuals or people with open wounds or cuts. In conclusion, the large accumulation of microorganisms on workers' clothes combined with the overlap between fungal species for the different sample types, and the presence of pathogenic and allergenic microorganisms forms the basis for encouragement of good clothing hygiene during and post working hours.

"Increasing Incidence of Mucormycosis in Spanish inpatients from 1997-2018"

BACKGROUND

Mucormycosis is a worldwide angio-invasive fungal infection that is associated with high morbidity and mortality. A few European studies have focused on the epidemiology.

METHODOLOGY

A retrospective longitudinal descriptive study was performed with inpatients diagnosed with mucormycosis (ICD-9-CM, code 117.7, cases 1997-2015; and ICD-10, code B46, cases 2016-2018; along with length of hospital stay) in Spanish public hospitals between 1 January 1997 and 31 December 2018. Data were obtained from the Minimum Basic Data Set (CMBD in Spanish).

PRINCIPAL FINDINGS

A total of 962 patients were recorded; 665 were men. The mean age (±SD) was 55±18.8 years. The annual incidence rate increased from 0.74 to 1.24 cases per million person-years. The lethality rate was 31.3%. Renal failure (41.6%) and hematological malignancy (36.3%) were the main factors involved.

CONCLUSIONS

Mucormycosis is a rare infectious disease in Spain, but it has had a significantly increased incidence in the last two decades. Being an adult male and having diabetes, neoplasm or renal failure are the main factors associated. High mortality is usually associated mainly with hematological malignancy and renal failure. CMBD studies could be an efficient tool for assessing changes in the epidemiology of mucormycosis.

Liquid Biopsy for Invasive Mold Infections in Hematopoietic Cell Transplant Recipients With Pneumonia Through Next-Generation Sequencing of Microbial Cell-Free DNA in Plasma

BACKGROUND

Noninvasive diagnostic options are limited for invasive mold infections (IMIs). We evaluated the performance of a plasma microbial cell-free DNA sequencing (mcfDNA-Seq) test for diagnosing pulmonary IMI after hematopoietic cell transplant (HCT).

METHODS

We retrospectively assessed the diagnostic performance of plasma mcfDNA-Seq next-generation sequencing in 114 HCT recipients with pneumonia after HCT who had stored plasma obtained within 14 days of diagnosis of proven/probable Aspergillus IMI (n = 51), proven/probable non-Aspergillus IMI (n = 24), possible IMI (n = 20), and non-IMI controls (n = 19). Sequences were aligned to a database including >400 fungi. Organisms above a fixed significance threshold were reported.

RESULTS

Among 75 patients with proven/probable pulmonary IMI, mcfDNA-Seq detected ≥1 pathogenic mold in 38 patients (sensitivity, 51% [95% confidence interval {CI}, 39%-62%]). When restricted to samples obtained within 3 days of diagnosis, sensitivity increased to 61%. McfDNA-Seq had higher sensitivity for proven/probable non-Aspergillus IMI (sensitivity, 79% [95% CI, 56%-93%]) compared with Aspergillus IMI (sensitivity, 31% [95% CI, 19%-46%]). McfDNA-Seq also identified non-Aspergillus molds in an additional 7 patients in the Aspergillus subgroup and Aspergillus in 1 patient with possible IMI. Among 19 non-IMI pneumonia controls, mcfDNA-Seq was negative in all samples, suggesting a high specificity (95% CI, 82%-100%) and up to 100% positive predictive value (PPV) with estimated negative predictive values (NPVs) of 81%-99%. The mcfDNA-Seq assay was complementary to serum galactomannan index testing; in combination, they were positive in 84% of individuals with proven/probable pulmonary IMI.

CONCLUSIONS

Noninvasive mcfDNA-Seq had moderate sensitivity and high specificity, NPV, and PPV for pulmonary IMI after HCT, particularly for non-Aspergillus species.

Invasive fungal disease in children with acute myeloid leukaemia: An Australian multicentre 10-year review

BACKGROUND

Invasive fungal disease (IFD) is a common and important complication in children with acute myeloid leukaemia (AML). We describe the epidemiology of IFD in a large multicentre cohort of children with AML.

METHODS

As part of the retrospective multicentre cohort TERIFIC (The Epidemiology and Risk factors for Invasive Fungal Infections in immunocompromised Children) study, proven/probable/possible IFD episodes occurring in children with primary or relapsed/refractory AML from 2003 to 2014 were analysed. Crude IFD prevalence, clinical characteristics, microbiology and treatment were assessed. Kaplan-Meier survival analysis was used to estimate 6-month survival.

RESULTS

There were 66 IFD episodes diagnosed in 63 children with AML. The majority (75.8%) of episodes occurred in the context of primary AML therapy. During primary AML therapy, the overall prevalence was 20.7% (95% CI 15.7%-26.5%) for proven/probable/possible IFD and 10.3% (95% CI 6.7%-15.0%) for proven/probable IFD. Of primary AML patients, 8.2% had IFD diagnosed during the first cycle of chemotherapy. Amongst pathogens implicated in proven/probable IFD episodes, 74.4% were moulds, over a third (37.9%) of which were non-Aspergillus spp. Antifungal prophylaxis preceded 89.4% of IFD episodes, most commonly using fluconazole (50% of IFD episodes). All-cause mortality at 6 months from IFD diagnosis was 16.7% with IFD-related mortality of 7.6% (all in cases of proven IFD).

CONCLUSIONS

IFD is a common and serious complication during paediatric AML therapy. Mould infections, including non-Aspergillus spp. predominated in this cohort. A systematic approach to the identification of patients at risk, and a targeted prevention strategy for IFD is needed.

Scedosporium apiospermum Pneumonia in an Immunocompetent Host

Invasive fungal infections are being increasingly identified recently. Scedosporium is a significant cause of non-Aspergillus mold infection. It can cause disseminated disease in an immunocompromised host and localized pulmonary infection in immunocompetent ones, especially in those with preformed lung cavities. We present a case of scedosporiosis in an elderly female with bronchiectasis who presented with refractory pulmonary symptoms and infiltrates. The case emphasizes the need to keep the fungal infection in the differential diagnosis of refractory infiltrates in immunocompetent individuals without preformed cavities if they have bronchiectasis. Voriconazole monotherapy can be used as the first-line in proven cases of scedosporiosis.

Recovery and Its Dynamics of Filamentous Fungi from Clinical Specimen Cultures: An Extensive Study

The culture method remains vital in diagnosing fungal infections, but extensive data-based evaluation of the method, especially for filamentous fungi (molds), is minimal. The purpose of this study was to characterize mold recoveries from fungal cultures and the impact of media and incubation duration. Clinical specimens for fungal cultures were submitted primarily from the eastern and central United States, and mold isolation data were prospectively collected and analyzed. A total of 1,821 molds in 59 genera were isolated from 1,687 positive specimens, accounting for approximately 5.6% of our cohort of 30,000 fungal cultures. Within 2 weeks, nearly 90% of molds and 97.3% of Aspergillus fumigatus complex were recovered (>95% confidence interval [CI]). All Mucorales fungi were recovered within 11 days of incubation. The recovery peak time was day 3 for Mucorales fungi, day 4 for hyaline molds, day 5 for dematiaceous molds, and day 7 for Onygenales fungi. The recovery of Histoplasma capsulatum and Trichophyton species in the fourth week of incubation reveals that a 3-week incubation time is insufficient. Inhibitory mold agar was the best medium for recovering all mold types among all tested specimen types, yielding nearly 78% of mold growth overall, indicating the necessity of selective medium for fungal cultures. IMPORTANCE Fungal culture is the gold standard method of diagnosing fungal infections, but important information, such as the impact of media and incubation times on fungal recovery, is not well documented. This study addressed these gaps using extensive data-based evaluation focused on molds. We identified the best medium types and incubation times for better fungal culture practice. We analyzed 1,821 molds from 1,687 positive specimens in our cohort of approximately 30,000 fungal cultures. Mold recovery peaked between 3 and 7 days of incubation, dependent upon the type of mold. Some well-defined fungal pathogens, such as Histoplasma capsulatum and Trichophyton species, were isolated in the fourth week of incubation. Inhibitory mold agar was identified as the best medium for recovering all mold types among all tested specimen sources. As we are aware, this is the largest study of fungal culture methods and supports 4 weeks of incubation for optimal mold recovery.

Activity of Amphotericin B Formulations and Voriconazole, alone or in combination, against Biofilms of Scedosporium and Fusarium spp

Scedosporium and Fusarium species are emerging opportunistic pathogens, causing invasive fungal diseases in humans, particularly in immunocompromised patients. Biofilm-related infections are associated with increased morbidity and mortality. We herein assessed the ability of Scedosporium apiospermum (SA) and Fusarium solani species complex (FSSC) isolates to form biofilms and evaluated the efficacy of deoxycholate amphotericin B (D-AMB), liposomal amphotericin B (L-AMB) and voriconazole (VRC), alone or in combination, against mature biofilms. Biofilm formation was assessed by safranin staining and spectrophotometric measurement of optical density. Planktonic and biofilm damage was assessed by XTT reduction assay. Planktonic cell and biofilm MIC50's were determined as the minimum concentrations that caused ≥50% fungal damage compared to untreated controls. The combined activity of L-AMB (0.5-32 mg/L) with VRC (0.125-64 mg/L) against biofilms was determined by the checkerboard microdilution method and analyzed by the Bliss independence model. Biofilm MIC50's of D-AMB and L-AMB against SA isolates were 1 and 2 mg/L and against FSSC isolates were 0.5 and 1 mg/L, respectively. Biofilm MIC50's of VRC against SA and FSSC were 32 mg/L and >256 mg/L, respectively. Synergistic effects were observed at 2-4 mg/L of L-AMB combined with 4-16 mg/L of VRC against SA biofilms (mean ΔE±standard error: 17% ± 3.7%). Antagonistic interactions were found at 0.5-4 mg/L of L-AMB combined with 0.125-16 mg/L of VRC against FSSC isolates with -28% ± 2%. D-AMB and L-AMB were more efficacious against SA and FSSC biofilms than VRC.

[Invasive fungal infection over the last 30 years]

Clinical mycology is in continuous development. The appearance of new clinical guidelines has made it possible to improve the approach to opportunistic fungal infections, especially in immunosuppressed patients (oncohematological and/or transplant recipients). At the same time, the development of new diagnostic tools and new antifungals with a greater spectrum of action and fewer side effects have led to faster diagnoses and treatments that are more effective. Along with these advances, there has been a change in the epidemiology of invasive fungal infection (IFI), with the appearance of new patients (e.g., COPD, liver cirrhosis, post-influenza) and new microorganisms (Candida auris, Lomentospora prolificans, mucorales), and resistant fungi (isolates of Aspergillus resistant to azoles) which the clinician must take into account when choosing the treatment of a patient with an IFI. In this paper we will briefly review the advances in recent decades and the emerging problems.

Trichoderma longibrachiatum and Aspergillus fischeri Infection as a Cause of Skin Graft Failure in a Patient with Critical Burns after Liver Transplantation

Infectious complications are responsible for the majority of mortalities and morbidities of patients with critical burns. Although bacteria are the predominant etiological agents in such patients, yeasts and fungi have become relatively common causes of infections over the last decade. Here, we report a case of a young man with critical burns on 88% TBSA (total body surface area) arising as a part of polytrauma. The patient's history of orthotopic liver transplantation associated with the patient's need to use combined immunosuppressant therapy was an additional complication. Due to deep burns in the forearm region, we have (after a suitable wound bed preparation) applied a new bi-layered dermal substitute. The patient, however, developed a combined fungal infection in the region of this dermal substitute caused by Trichoderma longibrachiatum and Aspergillus fischeri (the first case ever reported). The infection caused the loss of the split-thickness skin grafts (STSGs); we had to perform repeated hydrosurgical and mechanical debridement and a systemic antifungal treatment prior to re-application of the STSGs. The subsequent skin transplant was successful.

Recent Trends in the Epidemiology of Fungal Infections

The breadth of fungi causing human disease and the spectrum of clinical presentations associated with these infections has widened. Epidemiologic trends display dramatic shifts with expanding geographic ranges, identification of new at-risk groups, increasing prevalence of resistant infections, and emergence of novel multidrug-resistant pathogenic fungi. Certain fungi have been transmitted between patients in clinical settings. Major health events not typically associated with mycoses resulted in larger proportions of the population susceptible to secondary fungal infections. Many health care-related, environmental, and socioeconomic factors have influenced these epidemiologic shifts. This review summarizes updates to clinically significant fungal pathogens in North America.

Drug Repurposing in Medical Mycology: Identification of Compounds as Potential Antifungals to Overcome the Emergence of Multidrug-Resistant Fungi

Immunodepression, whether due to HIV infection or organ transplantation, has increased human vulnerability to fungal infections. These conditions have created an optimal environment for the emergence of opportunistic infections, which is concomitant to the increase in antifungal resistance. The use of conventional antifungal drugs as azoles and polyenes can lead to clinical failure, particularly in immunocompromised individuals. Difficulties related to treating fungal infections combined with the time required to develop new drugs, require urgent consideration of other therapeutic alternatives. Drug repurposing is one of the most promising and rapid solutions that the scientific and medical community can turn to, with low costs and safety advantages. To treat life-threatening resistant fungal infections, drug repurposing has led to the consideration of well-known and potential molecules as a last-line therapy. The aim of this review is to provide a summary of current antifungal compounds and their main resistance mechanisms, following by an overview of the antifungal activity of non-traditional antimicrobial drugs. We provide their eventual mechanisms of action and the synergistic combinations that improve the activity of current antifungal treatments. Finally, we discuss drug repurposing for the main emerging multidrug resistant (MDR) fungus, including the Candida auris, Aspergillus or Cryptococcus species.

Clinical Accuracy and Impact of Plasma Cell-Free DNA Fungal PCR Panel for Non-Invasive Diagnosis of Fungal Infection

BACKGROUND

Invasive fungal infection (IFI) is a growing cause of morbidity and mortality in oncology and transplant patients. Diagnosis of IFI is often delayed due to need for invasive biopsy and low sensitivity of conventional diagnostic methods. Fungal cell-free DNA (cfDNA) detection in plasma is a novel testing modality for the non-invasive diagnosis of IFI.

METHODS

A novel bioinformatic pipeline was created to interrogate fungal genomes and identify multicopy sequences for cfDNA PCR targeting. A real-time PCR panel was developed for 12 genera and species most commonly causing IFI. Sensitivity and specificity of the fungal PCR panel were determined using plasma samples from patients with IFI and non-IFI controls. Clinical impact of fungal PCR panel was evaluated prospectively based on the treating team's interpretation of the results.

RESULTS

Overall, the sensitivity and specificity were 56.5% (65/115, 95% confidence interval [CI], 47.4%-65.2%) and 99.5% (2064/2075; 95% CI, 99.0%-99.7%), respectively. In the subset of patients with an optimized plasma volume (2mL), sensitivity was 69.6% (48/69; 95% CI, 57.9%-79.2%). Sensitivity was 91.7% (11/12; 95% CI, 62.5%-100%) for detection of Mucorales agents, 56.3% (9/16; 95% CI, 33.2%-76.9%) for Aspergillus species, and 84.6% (11/13; 95% CI, 56.5%-96.9%) for Candida albicans. In a prospective evaluation of 226 patients with suspected IFI, cfDNA testing was positive in 47 (20.8%) patients and resulted in a positive impact on clinical management in 20/47 (42.6%).

CONCLUSIONS

The fungal cfDNA PCR panel offers a non-invasive approach to early diagnosis of IFI, providing actionable results for personalized care.

Deuterium-labeled Raman tracking of glucose accumulation and protein metabolic dynamics in Aspergillus nidulans hyphal tips

Filamentous fungi grow exclusively at their tips, where many growth-related fungal processes, such as enzyme secretion and invasion into host cells, take place. Hyphal tips are also a site of active metabolism. Understanding metabolic dynamics within the tip region is therefore important for biotechnology and medicine as well as for microbiology and ecology. However, methods that can track metabolic dynamics with sufficient spatial resolution and in a nondestructive manner are highly limited. Here we present time-lapse Raman imaging using a deuterium (D) tracer to study spatiotemporally varying metabolic activity within the hyphal tip of Aspergillus nidulans. By analyzing the carbon-deuterium (C-D) stretching Raman band with spectral deconvolution, we visualize glucose accumulation along the inner edge of the hyphal tip and synthesis of new proteins from the taken-up D-labeled glucose specifically at the central part of the apical region. Our results show that deuterium-labeled Raman imaging offers a broadly applicable platform for the study of metabolic dynamics in filamentous fungi and other relevant microorganisms in vivo.

Invasive Scedosporium and Lomentosora infections in the era of antifungal prophylaxis: A 20-year experience from a single centre in Spain

BACKGROUND

Non-Aspergillus mould infections such as those caused by Scedosporium apiospermum or Lomentospora prolificans are an emerging threat. Few studies have monitored their long-term incidence.

OBJECTIVES

To analyse the epidemiology, risk factors, clinical features and incidence of patients with proven and probable infections.

PATIENTS/METHODS

Patients admitted to Gregorio Marañón Hospital between 1998 and 2017 and from whom Scedosporium/Lomentospora was isolated were studied. Subjects were classified as having a probable/proven invasive fungal infection or colonization. Molecular identification and antifungal susceptibility testing of isolates causing infection were performed, as well as a description of the patients and incidence of infection.

RESULTS

One or more Scedosporium/Lomentospora isolates were identified in 67 patients. Sixteen (23.9%) patients had developed infection: 11 scedosporiosis and 5 lomentosporiosis. Stable incidence was observed throughout the study period. Most patients were immunosuppressed and the most common underlying diseases were haematologic malignancy (25%), solid organ transplantation (25%) and chronic corticoid therapy (25%). Breakthrough infection occurred in four patients, 2/11 (18.2%) cases of scedosporiosis and 2/5 (40%) of lomentosporiosis. Overall mortality was 54.5% (6/11) and 80% (4/5) in subjects with scedosporiosis and lomentosporiosis, respectively. High MICs of amphotericin B and remarkable inter-species susceptibility variability to triazoles was observed for most isolates.

CONCLUSIONS

In contrast to previous studies, the incidence of scedosporiosis and lomentosporiosis has not increased at our hospital over the years. The tendency to cause disseminated infection and a reduced susceptibility to most antifungal agents leads to high mortality.

Unexpected mould diversity in clinical isolates from French Guiana and associated identification difficulties

New mold species are increasingly reported in invasive fungal infections. However, these fungi are often misdiagnosed or undiagnosed due to the use of inappropriate laboratory diagnostic tools. Tropical countries, such as French Guiana, harbor a vast diversity of environmental fungi representing a potential source of emerging pathogens. To assess the impact of this diversity on the accuracy of mold-infection diagnoses, we identified mold clinical isolates in French Guiana during a five-month follow-up using both microscopy and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. In total, 38.8% of the 98 obtained molds isolates could not be identified and required a DNA-based identification. Fungal diversity was high, including 46 species, 26 genera, and 13 orders. Fungal ecology was unusual, as Aspergillus species accounted for only 27% of all isolates, and the Nigri section was the most abundant out of the six detected Aspergillus sections. Macromycetes (orders Agaricales, Polyporales, and Russulales) and endophytic fungi accounted for respectively 11% and 14% of all isolates. Thus, in tropical areas with high fungal diversity, such as French Guiana, routine mold identification tools are inadequate. Molecular identifications, as well as morphological descriptions, are necessary for the construction of region-specific mass spectrum databases. These advances will improve the diagnosis and clinical management of new fungal infections.

LAY SUMMARY

In French Guiana, environmental fungal diversity may be a source of emerging pathogens. We evaluated microscopy and mass spectrometry to identify mold clinical isolates. With 39% of unidentified isolates, a region-specific mass spectrum database would improve the diagnosis of new fungal infections.

Influence of Nonthermal Atmospheric Plasma-Activated Water on the Structural, Optical, and Biological Properties of Aspergillus brasiliensis Spores

Plasma-activated water (PAW) has emerged as a platform for sterilizing fungal pathogens. In this study, we investigated the influence of PAW on black melanized spores of Aspergillus brasiliensis to explore the mechanism of fungal spore inactivation. PAW was prepared by activating deionized water with a nonthermal atmospheric pressure air plasma jet (soft plasma jet). The concentrations of H2O2 and NOx in the PAW treated by the soft plasma jet for 3 min were 50 μM and 1.8 mM, respectively, and the pH of the PAW was 3.10. The reactive oxygen and nitrogen species (RONS) in the PAW increased with longer plasma activation time. After being treated for 30 min in the PAW with a plasma activation time of 3 min, the spore viability dramatically dropped to 15%. The viabilities of 0.3% H2O2- and 0.3% HNO3-treated spores were 22% and 42%, respectively. The breakage of the spore cell wall by the PAW was revealed in scanning electron microscope images and flow cytometry measurements. Disruption of cell wall integrity provides a path for intracellular components to escape and RONS of the PAW can attack intracellular components directly. Degradation of high molecular genomic DNA was also observed by agarose gel electrophoresis. These results suggest that long-lived reactive species generated in the PAW play an important role in the inactivation of melanized fungal spores. Consequently, PAW produced by a soft plasma jet can be applied to sterilize bioprotective walled fungal spores in a relatively large volume.

Sarocladium and Acremonium infections: New faces of an old opportunistic fungus

The genera Acremonium and Sarocladium comprise a high diversity of morphologically and genetically related fungi generally found in the environment, although a few species, mainly Sarocladium kiliense and Acremonium egyptiacum, can also be involved in many human infections. Clinical management of opportunistic infections caused by these fungi is very complex, since their correct identification is unreliable, and they generally show poor antifungal response. More than 300 clinical cases involving a broad range of Acremonium/Sarocladium infections have so far been published, and with this review we aim to compile and provide a detailed overview of the current knowledge on Acremonium/Sarocladium human infections in terms of presentation, diagnosis, treatments and prognoses. We also aim to summarise and discuss the data currently available on their antifungal susceptibility, emphasising the promising results obtained with voriconazole as well as their impact in terms of animal infections.

Identification by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry and Antifungal Susceptibility Testing of Non-Aspergillus Molds

Non-Aspergillus molds including Mucorales, Fusarium, and Scedosporium, etc. are emerging pathogens leading to higher mortality in immunocompromised patients. Fifty-two isolates of genetically confirmed non-Aspergillus molds representing 16 species from 8 genera were collected to evaluate the performance of the Bruker matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) in identification of non-Aspergillus molds. Antifungal susceptibilities were determined through the Clinical & Laboratory Standards Institute (CLSI) M38-A2 broth microdilution method and the Sensititre YeastOne colorimetric method. Bruker MALDI-TOF MS identified 57.7% (30/52) of isolates cultured in broth and 15.4% (8/52) of isolates cultured on solid agar media to the species level, respectively, according to standard interpretation criteria. Lowering the species level cut-off value (COV) from ≥2.0 to ≥1.7 could improve the MALDI-TOF MS species-level identification rate to 67.3% (38/52) for isolates cultured on solid media, with a slight increase of false identification rate of 2.6% (1/38). Amphotericin B was the most in vitro fungistatic-active agent for 98.1% (51/52) of the tested non-Aspergillus molds, with minimum inhibitory concentrations (MICs) of ≤2 μg/mL. The susceptibilities to triazoles varied, with MICs of 0.12 to >16 μg/mL among different species of non-Aspergillus molds. The correlation between the CLSI method and Sensititre YeastOne on antifungal susceptibility testing of non-Aspergillus molds was good, with essential agreement (EA) rates of >90% for triazoles and echinocandins except amphotericin B, which had a lower EA rate of 84.6%. In conclusion, a favorable performance of the Bruker MALDI-TOF MS in identification of clinical non-Aspergillus isolates directly inoculated on solid agar media could be achieved with the adoption of alternative interpretation criteria. Antifungal susceptibility testing is important for non-Aspergillus molds, especially when information on triazole susceptibility is required, and the Sensititre YeastOne is a practical and reliable method to determine antifungal susceptibilities of non-Aspergillus molds.

Human fusariosis: An emerging infection that is difficult to treat

Fusarium spp. has been associated with a broad spectrum of emerging infections collectively termed fusariosis. This review includes articles published between 2005 and 2018 that describe the characteristics, clinical management, incidence, and emergence of these fungal infections. Fusarium solani and F. oxysporum are globally distributed and represent the most common complexes. Few therapeutic options exist due to intrinsic resistance, especially for the treatment of invasive fusariosis. Therefore, the use of drug combinations could be an important alternative for systemic antifungal resistance. Increase in the number of case reports on invasive fusariosis between 2005 and 2018 is evidence of the emergence of this fungal infection.

Evaluation of ID Fungi Plates Medium for Identification of Molds by MALDI Biotyper

MALDI-TOF mass spectrometry (MS) identification of pathogenic filamentous fungi is often impaired by difficulties in harvesting hyphae embedded in the medium and long extraction protocols. The ID Fungi Plate (IDFP) is a novel culture method developed to address such difficulties and improve the identification of filamentous fungi by MALDI-TOF MS. We cultured 64 strains and 11 clinical samples on IDFP, Sabouraud agar-chloramphenicol (SAB), and ChromID Candida agar (CAN2). We then compared the three media for growth, ease of harvest, amount of material picked, and MALDI-TOF identification scores after either rapid direct transfer (DT) or a long ethanol-acetonitrile (EA) extraction protocol. Antifungal susceptibility testing and microscopic morphology after subculture on SAB and IDFP were also compared for ten molds. Growth rates and morphological aspects were similar for the three media. With IDFP, harvesting of fungal material for the extraction procedure was rapid and easy in 92.4% of cases, whereas it was tedious on SAB or CAN2 in 65.2% and 80.3% of cases, respectively. The proportion of scores above 1.7 (defined as acceptable identification) were comparable for both extraction protocols using IDFP (P = 0.256). Moreover, rates of acceptable identification after DT performed on IDFP (93.9%) were significantly higher than those obtained after EA extraction with SAB (69.7%) or CAN2 (71.2%) (P = <0.001 and P = 0.001, respectively). Morphological aspects and antifungal susceptibility testing were similar between IDFP and SAB. IDFP is a culture plate that facilitates and improves the identification of filamentous fungi, allowing accurate routine identification of molds with MALDI-TOF-MS using a rapid-extraction protocol.

Towards a risk evaluation of workers' exposure to handborne and airborne microbial species as exemplified with waste collection workers

Bioaerosol exposure is associated with health problems. The aim of this study is to evaluate whether it is possible to assess the risks posed by waste collection workers' exposure through identification and characterization of bacterial and fungal species, to which the workers are exposed. Using MALDI-TOF MS, microorganisms in waste collection workers' exposure through air, hand, and contact with the steering wheel were identified. Fungi found in high concentrations from the workers' exposure were characterized for the total inflammatory potential (TIP), cytotoxicity, and biofilm-forming capacity. In total, 180 different bacterial and 37 different fungal species in the workers' exposure samples were identified. Some of them belong to Risk Group 2, e.g. Escherichia coli, Klebsiella oxytoca, Staphylococcus aureus, and Aspergillus fumigatus, some have been associated with occupational health problems e.g. Penicillium citrinum and P. glabrum and some are described as emerging pathogens e.g. Aureobasidium pullulans. The TIP of fungal species was dose-dependent. High TIP values were found for Penicillium italicum, P. brevicompactum, P. citrinum, and P. glabrum. Several species were cytotoxic, e.g. A. niger and P. expansum, while some, e.g. P. chrysogenum, did not affect the cell viability. Based on waste workers' average inhalation rate, they inhaled up to 2.3 × 10⁴ cfu of A. niger, 7.4 × 10⁴ cfu of P. expansum, and 4.0 × 10⁶ cfu of P. italicum per work day. Some species e.g. A. niger and P. citrinum were able to form biofilm. In conclusion, the workers were exposed to several species of microorganisms of which some to varying degrees can be evaluated concerning risk. Thus, some microorganisms belong to Risk Group 2, and some are described as causing agents of occupational health problems, emerging pathogens, or intrinsically antibiotic resistant. For some other species very little is known. The TIP, cytotoxicity, and ability to form biofilm of the dominating fungi support and expand previous findings. These parameters depended on the species and the dose, thus highlighting the importance of species identification and exposure level in the risk assessment of exposure.

Molecular identification of Fusarium species complex isolated from clinical samples and its antifungal susceptibility patterns

Background and Purpose:

More than 300 Fusarium species are grouped into approximately 23 species complexes out of which around 70 are involved in human infections. The nomenclature of these species has undergone considerable changes in recent years. These species cause localized infections in individuals while inducing systemic infections mainly in immunocompromised patients. The present study was conducted to identify Fusarium species in clinical isolates by molecular methods and determine their in vitro minimum inhibitory concentration (MIC) patterns to address the lack of data in this domain in Northern India.

Materials and Methods:

For the purpose of the study, Fusarium isolates obtained from various clinical samples were sent to the Westerdijk Fungal Biodiversity Institute, Utrecht, the Netherlands, for molecular identification. The MIC testing was performed using the microbroth dilution method as per the Clinical and Laboratory Standards Institute reference method (M38-A2).

Results:

Fusarium was isolated from 33 patients (i.e., 1, 1, 2, 14, and 15 cases with endophthalmitis, sinusitis, pulmonary involvement, onychomycosis, and keratitis, respectively). These 33 isolates belonged to three species complexes, namely F. solani species complex (FSSC; n=13), F. fujikuroi species complex (FFSC; n=13), and F. incarnatumequiseti species complex (FIESC; n=7). The species identified within FSSC, FFSC, and FIESC included F. keratoplasticum (n=6)/F. falciforme (n=6)/F. solani (n=1), F. proliferatum (n=7)/F. sacchari (n=5)/F. anthophilum (n=1), and F. incarnatum SC species (n=6)/F. equiseti SC species (n=1), respectively. The MIC results showed that all isolates had a lower MIC against amphotericin B than against the other antifungal agents.

Alteration of Fermentative Metabolism Enhances Mucor circinelloides Virulence

The fungus Mucor circinelloides undergoes yeast-mold dimorphism, a developmental process associated with its capability as a human opportunistic pathogen. Dimorphism is strongly influenced by carbon metabolism, and hence the type of metabolism likely affects fungus virulence. We investigated the role of ethanol metabolism in M. circinelloides virulence. A mutant in the adh1 gene (M5 strain) exhibited higher virulence than the wild-type (R7B) and the complemented (M5/pEUKA-adh1 ⁺) strains, which were nonvirulent when tested in a mouse infection model. Cell-free culture supernatant (SS) from the M5 mutant showed increased toxic effect on nematodes compared to that from R7B and M5/pEUKA-adh1 ⁺ strains. The concentration of acetaldehyde excreted by strain M5 in the SS was higher than that from R7B, which correlated with the acute toxic effect on nematodes. Remarkably, strain M5 showed higher resistance to H₂O₂, resistance to phagocytosis, and invasiveness in mouse tissues and induced an enhanced systemic inflammatory response compared with R7B. The mice infected with strain M5 under disulfiram treatment exhibited only half the life expectancy of those infected with M5 alone, suggesting that acetaldehyde produced by M. circinelloides contributes to the toxic effect in mice. These results demonstrate that the failure in fermentative metabolism, in the step of the production of ethanol in M. circinelloides, contributes to its virulence, inducing a more severe tissue burden and inflammatory response in mice as a consequence of acetaldehyde overproduction.

New azole antifungals with a fused triazinone scaffold

We identified a new series of azole antifungal agents bearing a pyrrolotriazinone scaffold. These compounds exhibited a broad in vitro antifungal activity against pathogenic Candida spp. (fluconazole-susceptible and fluconazole-resistant) and were 10- to 100-fold more active than voriconazole against two Candida albicans isolates with known mechanisms of azole resistance (overexpression of efflux pumps and/or specific point substitutions in the Erg11p/CYP51 enzyme). Our lead compound 12 also displayed promising in vitro antifungal activity against some filamentous fungi such as Aspergillus fumigatus and the zygomycetes Rhizopus oryzae and Mucor circinelloides and an in vivo efficiency against two murine models of lethal systemic infections caused by Candida albicans.

Molecular Diagnostic Advances in Transplant Infectious Diseases

PURPOSE OF REVIEW

The infectious complications of transplantation can have devastating consequences for patients. Early and accurate diagnosis is essential to good outcomes. This review describes recent advances in pathogen-directed diagnostic testing and discusses the role of new methods for transplant infectious diseases.

RECENT FINDINGS

Several molecular assays have been introduced into clinical practice in recent years. When the results of rapid testing are linked to patient-specific interventions, improved outcomes can be realized. Syndromic testing along with metagenomic next-generation sequencing (mNGS) represents novel approaches to infection diagnosis. However, the optimal use of these tests for transplant patients along with an overall assessment of cost-effectiveness demands further study. Molecular diagnostics are revolutionizing transplant care. Clinicians need to be aware of the current diagnostic landscape and have a working knowledge of the nuances related to test performance, result interpretation, and cost.

Angioinvasive, cutaneous infection due to Colletotrichum siamense in a stem cell transplant recipient: Report and review of prior cases

Colletotrichum is an important fungal plant pathogen, yet an uncommon cause of human disease. Herein we report a case of invasive, cutaneous infection in a stem cell transplant recipient due to Colletotrichum species, with accompanying review of the literature. The infection was successfully treated with a combination of liposomal amphotericin B and voriconazole. Multilocus phylogenetic analysis revealed that the distinct isolate belongs to Colletotrichum siamense, a member of the Colletotrichum gloeosporioides species complex not previously described as a human pathogen. Colletotrichum infection remains in the differential for skin lesions in the immune compromised host.

Increased species-assignment of filamentous fungi using MALDI-TOF MS coupled with a simplified sample processing and an in-house library

In this study we evaluated the capacity of MALDI-TOF MS (Bruker Daltonics, Bremen, Germany) to identify clinical mould isolates. We focused on two aspects of MALDI-TOF MS identification: the sample processing and the database. Direct smearing of the sample was compared with a simplified processing consisting of mechanical lysis of the moulds followed by a protein extraction step. Both methods were applied to all isolates and the Filamentous Fungi Library 1.0 (Bruker Daltonics) was used for their identification. This approach allowed the correct species-level identification of 25/34 Fusarium spp. and 10/10 Mucor circinelloides isolates using the simplified sample processing. In addition, 7/34 Fusarium spp. and 1/21 Pseudallescheria/Scedosporium spp. isolates were correctly identified at the genus level. The remaining isolates-60-could not be identified using the commercial database, mainly because of the low number of references for some species and the absence of others. Thus, an in-house library was built with 63 local isolates previously characterized using DNA sequence analysis. Its implementation allowed the accurate identification at the species level of 94 isolates (91.3%) and the remaining nine isolates (8.7%) were correctly identified at the genus level. No misidentifications at genus level were detected. In conclusion, with improvements of both the sample preparation and the feeding of the database, MALDI-TOF MS is a reliable, ready to use method to identify moulds of clinical origin in an accurate, rapid, and cost-effective manner.

Full genome sequence of a new polymycovirus infecting Fusarium redolens

By screening a collection of Fusarium spp. for the presence of dsRNA, the Fusarium redolens strain A63-1 was found harboring a pattern of multiple dsRNA bands when analyzed by agarose gel electrophoresis. Using NextSeq Illumina sequencing, the full sequences of eight dsRNA molecules were determined, compared to databases, and gathered into a new viral genome. This novel virus shares similarities with mycoviruses that were recently grouped in the proposed family "Polymycoviridae". Hence, the name "Fusarium redolens polymycovirus 1" is proposed for this virus. Each viral dsRNA contains only one ORF, except dsRNA 7, which has an additional one. Based on amino acid sequence similarities, the functions of the proteins encoded by dsRNA 1-4 can be hypothesized. On the other hand, the putative proteins encoded by dsRNA 5-8 exhibit no relevant homology to known proteins. In this report, the full genome sequence of this new virus is presented along with a primary bioinformatics analysis.

The effect of temperature on airborne filamentous fungi in the indoor and outdoor space of a hospital

Fungi are one of the bioaerosols in indoor air of hospitals. They have adverse effects on staff and patients. The aim of this study was to investigate the effects of three incubation temperature on the density and composition of airborne fungi in an indoor and outdoor space of hospital. Sabouraud dextrose agar was used for culture the fungi. For improvement of aseptic properties, chloramphenicol was added to this medium. The density of airborne fungi was less than 282 CFU/m³. The highest density was detected in emergency room and the lowest of them was in neonatal intensive care unit (NICU) and operation room (OR). Results showed that fungi levels at 25 °C were higher than 37 and 15 °C (p = 0.006). In addition, ten different genera of fungi were identified in all departments. The predominant fungi were Fusarium spp., Penicillium spp., Paecilomyces spp., and Aspergillus niger. Moreover, the density and trend of distribution of Fusaruim spp. in the indoor space was directivity to outdoor space by ventilation system. The present study has provided that incubation temperature had effect on airborne fungi remarkably. We are suggested that more studies would be conducted on incubation temperature and other ambient factors on airborne fungi.

Detection and identification of fungi in bronchoalveolar lavage fluid from immunocompromised patients using panfungal PCR

Rapid diagnostics of fungal pneumonia and initiation of appropriate therapy are still challenging. In this study, we used two panfungal assays to test bronchoalveolar lavage fluid (BALF) samples to prove their ability to confirm invasive fungal disease diagnosis and identify causative agents. Two methods targeting different fungal rDNA regions were used, and the obtained PCR products were sequenced directly or after cloning. In total, 106 BALF samples from 104 patients were tested. After sequencing, we obtained 578 sequences. Four hundred thirty-seven sequences were excluded from further analysis due to duplication (n = 335) or similarity with sequences detected in the extraction control sample (n = 102); 141 unique sequences were analyzed. Altogether, 23/141 (16%) of the fungi detected belonged to pathogenic species, and 63/141 (45%) were identified as various yeasts; a variety of environmental or very rare fungal human pathogens represented 29/141 (21%) of the total and 26/141 (18%) were described as uncultured fungus. Panfungal PCR detected fungal species that would be missed by specific methods in only one case (probable cryptococcosis). Panfungal PCR followed by sequencing has limited use for testing BALF samples due to frequent commensal or environmental fungal species pickup.