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Cystic fibrosis (CF) is characterised by chronic airway infection with bacteria and fungi. Infections caused by Scedosporium/Lomentospora species can occur and are difficult to treat. Moulds belonging to the genus Scedosporium/Lomentospora are detected most frequently in respiratory samples of patients with CF, next to Aspergillus spp. Our aim was to define pulmonary fungal infections due to Scedosporium/Lomentospora in CF and to study the antimycotic treatment. In this multicentre study (12 centres; duration January 2008 to December 2014) 31 patients with a lung infection caused by moulds of the genus Scedosporium/Lomentospora were included. 36 courses of antifungal treatment were documented. Scedosporium apiospermum sensu stricto accounted for 48.4% of cases. In 20/31 patients a therapeutic response under antimycotics (median duration 3.9 months) was achieved. Triple and double therapy was significantly more effective compared to monotherapy regarding FEV 1 , radiology, and symptoms. This data suggests that combined treatment is superior to monotherapy in patients with CF., (Copyright © 2018 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Fungal respiratory colonization of cystic fibrosis (CF) patients emerges as a new concern; however, the heterogeneity of mycological protocols limits investigations. We first aimed at setting up an efficient standardized protocol for mycological analysis of CF sputa that was assessed during a prospective, multicenter study: "MucoFong" program (PHRC-06/1902). Sputa from 243 CF patients from seven centers in France were collected over a 15-month period and submitted to a standardized protocol based on 6 semi-selective media. After mucolytic pretreatment, sputa were plated in parallel on cycloheximide-enriched (ACT37), erythritol-enriched (ERY37), benomyl dichloran-rose bengal (BENO37) and chromogenic (CAN37) media incubated at 37 °C and on Sabouraud-chloramphenicol (SAB27) and erythritol-enriched (ERY27) media incubated at 20-27 °C. Each plate was checked twice a week during 3 weeks. Fungi were conventionally identified; time for detection of fungal growth was noted for each species. Fungal prevalences and media performances were assessed; an optimal combination of media was determined using the Chi-squared automatic interaction detector method. At least one fungal species was isolated from 81% of sputa. Candida albicans was the most prevalent species (58.8%), followed by Aspergillus fumigatus (35.4%). Cultivation on CAN37, SAB27, ACT37 and ERY27 during 16 days provided an optimal combination, detecting C. albicans, A. fumigatus, Scedosporium apiospermum complex and Exophiala spp. with sensitivities of 96.5, 98.8, 100 and 100%. Combination of these four culture media is recommended to ensure the growth of key fungal pathogens in CF respiratory specimens. The use of such consensual protocol is of major interest for merging results from future epidemiological studies.

The airways of patients with cystic fibrosis (CF) are frequently colonized by various filamentous fungi, mainly Aspergillus fumigatus and Scedosporium species. To establish within the respiratory tract and cause an infection, these opportunistic fungi express pathogenic factors allowing adherence to the host tissues, uptake of extracellular iron, or evasion to the host immune response. During the colonization process, inhaled conidia and the subsequent hyphae are exposed to reactive oxygen species (ROS) and reactive nitrogen species (RNS) released by phagocytic cells, which cause in the fungal cells an oxidative stress and a nitrosative stress, respectively. To cope with these constraints, fungal pathogens have developed various mechanisms that protect the fungus against ROS and RNS, including enzymatic antioxidant systems. In this review, we summarize the different works performed on ROS- and RNS-detoxifying enzymes in fungi commonly encountered in the airways of CF patients and highlight their role in pathogenesis of the airway colonization or respiratory infections. The potential of these enzymes as serodiagnostic tools is also emphasized. In addition, taking advantage of the recent availability of the whole genome sequence of S. apiospermum, we identified the various genes encoding ROS- and RNS-detoxifying enzymes, which pave the way for future investigations on the role of these enzymes in pathogenesis of these emerging species since they may constitute new therapeutics targets.

During the past decades, atomic force microscopy (AFM) has emerged as a powerful tool in microbiology. Although most of the works concerned bacteria, AFM also permitted major breakthroughs in the understanding of physiology and pathogenic mechanisms of some fungal species associated with cystic fibrosis. Complementary to electron microscopies, AFM offers unprecedented insights to visualize the cell wall architecture and components through three-dimensional imaging with nanometer resolution and to follow their dynamic changes during cell growth and division or following the exposure to drugs and chemicals. Besides imaging, force spectroscopy with piconewton sensitivity provides a direct means to decipher the forces governing cell-cell and cell-substrate interactions, but also to quantify specific and non-specific interactions between cell surface components at the single-molecule level. This nanotool explores new ways for a better understanding of the structures and functions of the cell surface components and therefore may be useful to elucidate the role of these components in the host-pathogen interactions as well as in the complex interplay between bacteria and fungi in the lung microbiome.

The genus Scedosporium, which comprises at least five clinically relevant species, i.e. Scedosporium apiospermum, Scedosporium boydii, Scedosporium aurantiacum, Scedosporium dehoogii and Scedosporium minutisporum, ranks the second among the filamentous fungi colonizing the airways of patients with cystic fibrosis (CF). This colonization of the airways is thought to contribute to the inflammatory reaction leading to a progressive deterioration of the lung function. Additionally, these colonizing fungi may lead to severe disseminated infections in case of lung transplantation. Therefore, considering the low susceptibility of Scedosporium species to all current antifungal drugs, preventive measures should be defined to reduce the risk of exposure to these fungi for non-colonized CF patients. With this in mind, several studies have been conducted to elucidate the ecology of these fungi and to define possible sources of patient contamination. This review will summarize the major outcomes of those studies, including: the clear demonstration that ecological niches of Scedosporium species are strongly impacted by human activities, and the ability of Scedosporium species to degrade aliphatic and aromatic pollutants which supports the high occurrence of these species in contaminated soils and polluted waters and makes them promising candidates for bioremediation purposes. Finally, prospects for future research in this field are proposed.

The achievement of a better life for cystic fibrosis (CF) patients is mainly caused by a better management and infection control over the last three decades. Herein, we want to summarize the cornerstones for an effective management of CF patients and to give an overview of the knowledge about the fungal epidemiology in this clinical context in Europe. Data from a retrospective analysis encompassing 66,616 samples from 3235 CF patients followed-up in 9 CF centers from different European countries are shown.

Cystic fibrosis (CF) is a genetic inherited disease due to mutations in the gene cystic fibrosis transmembrane conductance regulator (CFTR). Because of the huge diversity of CFTR mutations, the CF phenotypes are highly heterogeneous, varying from typical to mild form of CF, also called atypical CF. These atypical features are more frequently diagnosed at adolescence or adulthood, and among clinical signs and symptoms leading to suspect a mild form of CF, colonization or infection of the respiratory tract due to well-known CF pathogens should be a warning signal. Exophiala dermatitidis is a melanized dimorphic fungus commonly detected in respiratory specimens from CF patients, but only very rarely from respiratory specimens from non-CF patients. We described here two cases of chronic colonization of the airways by E. dermatitidis, with recurrent pneumonia and hemoptysis in one patient, which led clinicians to diagnose mild forms of CF in these elderly patients who were 68- and 87-year-old. These cases of late CF diagnosis suggest that airway colonization or respiratory infections due to E. dermatitidis in patients with bronchiectasis should led to search for a mild form of CF, regardless of the age and associated symptoms. On a broader level, in patients with chronic respiratory disease and recurrent pulmonary infections, an allergic bronchopulmonary mycosis or an airway colonization by CF-related fungi like E. dermatitidis or some Aspergillus, Scedosporium or Rasamsonia species, should be considered as potential markers of atypical CF and should led clinicians to conduct investigations for CF diagnosis.

Usually living as a soil saprophyte, the filamentous fungus Scedosporium boydii may also cause various infections in human. Particularly, it is one of the major causative agents of fungal colonization of the airways in patients with cystic fibrosis (CF). To compete with other microorganisms in the environment, fungi have evolved sophisticated strategies, including the production of secondary metabolites with antimicrobial activity that may also help them to establish successfully within the respiratory tract of receptive hosts. Here, the culture filtrate from a human pathogenic strain of S. boydii was investigated searching for an antibacterial activity, mainly against the major CF bacterial pathogens. A high antibacterial activity against Staphylococcus aureus, including methicillin-resistant strains of this species, was observed. Bio-guided fractionation and analysis of the active fractions by nuclear magnetic resonance or by high-performance liquid chromatography and high-resolution electrospray ionization-mass spectrometry allowed us to identify boydone A as responsible for this antibacterial activity. Together, these results suggest that this six-membered cyclic polyketide could be one of the virulence factors of the fungus. Genes involved in the synthesis of this secreted metabolite are currently being identified in order to confirm the role of this polyketide in pathogenesis., (© FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Species of the Scedosporium apiospermum complex (S. a complex) are emerging fungi responsible for chronic airway colonization in cystic fibrosis (CF) patients. Recent studies performed on Aspergillus fumigatus suggest that the colonization of the airways by filamentous fungi may contribute to the progressive deterioration of lung function., Methods: We studied S. a complex seroprevalence, as a marker of close contact between patient and the fungi, in a large monocentric cohort of CF patients attended in a reference centre in Lyon, France., Results: Serum samples from 373 CF patients were analysed. Antibodies against S. a complex were detected in 35 patients (9.4%). In multivariate analysis, S. a complex seropositivity was only associated with seropositivity to A. fumigatus., Conclusions: This study does not suggest an association between sensitization against S. a complex and poorer lung function in CF. Prospective studies are needed to evaluate the impact of both seropositivity and S. a complex colonization on the course of CF., (Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Scedosporium apiospermum is an emerging pathogen colonizing the airways of patients with cystic fibrosis (CF). While usually responsible for chronic colonization without clinical signs, this fungus may cause severe and often lethal infections in lung transplant recipients. Early diagnosis of its airway colonization and appropriate treatment are required to eradicate the fungus when a lung transplantation is planned. Here we propose an alternative to mycological examination of sputum samples based on extraction of siderophores by chromatography on Amberlite XAD-4, followed by high performance liquid chromatography analysis of the siderophore extract. Improvement of the extraction procedure was performed in a fractional factorial design which revealed the importance of prior ammonium sulfate precipitation of the proteins, alkalinization of the obtained solution and stirring during extraction. In order to verify the specificity of N(α)-methyl coprogen B for S. apiospermum, the method was applied on culture supernatants of different filamentous fungi colonizing the airways of CF patients, including some aspergilli and Exophiala dermatitidis. N(α)-methyl coprogen B was detected exclusively for species of the S. apiospermum complex. Likewise, sputum samples from colonized and non-colonized CF patients were analyzed, and the siderophore was detected exclusively in three out of the five specimens which were found by culture to contain S. apiospermum. Together these results confirmed N(α)-methyl coprogen B as a marker of the airway colonization by species of the S. apiospermum complex.

Filamentous fungi and yeasts are increasingly isolated from respiratory secretions of patients with cystic fibrosis (CF), and persistent fungal colonization of the airways of such patients is thought to exacerbate lung damage. While many independent studies have identified Aspergillus fumigatus complex as the principal colonizing fungus in CF, increased awareness of the role of fungi in CF pathology coupled with improved mycological culture and identification methods have resulted in a number of other fungi being isolated and reported from CF sputum samples, including A. terreus, members of the Pseudallescheria boydii/Scedosporium apiospermum complex, Exophiala dermatitidis, Paecilomyces and Penicillium species. However, the range of fungal pathogens isolated and the relative prevalence of individual species vary widely between reports from different geographical CF centres, and as yet no standardized method for the mycological examination of CF sputum samples has been adopted. Here, we examine the potential contribution of the mycological methods employed to examine CF respiratory secretions relative to the variability in the fungal biota reported. The role of direct microscopic examination of respiratory samples and the impact of the culture conditions used on the detection of specific fungal pathogens are addressed, and the potential significance of isolation of yeast species from CF patient airways is discussed.

Poorly sporulating Aspergillus isolates from patients with cystic fibrosis (CF) are generally identified in routine procedures as Aspergillus spp. In this study, we identified and characterized 11 isolates belonging to two unusual Aspergillus species of the section Fumigati (A. lentulus and Neosartorya pseudofischeri) recovered from four different patients. Aspergillus lentulus was found occasionally during a 10-year follow-up study of one CF patient colonized by A. fumigatus. Neosartorya pseudofischeri was isolated from three patients followed in different European hospitals. This species was recovered from two sputum samples of one patient, and from four successive samples of the two other patients, suggesting that it may be responsible for chronic colonization. Both species were isolated together with A. fumigatus. Isolates from both species did not grow at 50°C, and DNA sequence analysis, together with further morphological observations permitted identification at the species level. Growth at different temperatures and antifungal susceptibility were also investigated. All the isolates of N. pseudofischeri exhibited a very low susceptibility to voriconazole (VRZ) whereas a very low susceptibility to VRZ and amphotericin B was seen with the A. lentulus isolates.

We report eight cases of airway colonization by Geosmithia argillacea in patients with cystic fibrosis. This filamentous fungus, resembling members of the genera Penicillium and Paecilomyces, was identified by molecular analysis. All patients carried a mutation on each CFTR (cystic fibrosis transmembrane conductance regulator) allele, with at least one copy of the F508del mutation. The first isolation of this fungus occurred from F508del-homozygous patients at a younger age than in F508del-heterozygous patients. Before recovery of G. argillacea, all patients were treated with itraconazole; two of them had also received voriconazole for an Aspergillus fumigatus infection. However, antifungal susceptibility patterns showed high MICs of voriconazole for all isolates, and high MICs of amphotericin B and itraconazole for the majority of them, but mostly low minimum effective concentrations (MECs) of caspofungin. The appearance and persistence of G. argillacea in the airways were not associated with exacerbation of the disease. However, the clinical implications of G. argillacea, particularly in immunocompromised patients, remain a concern, particularly given recent observations suggesting that this fungus may also cause disseminated infections.

We report a case of disseminated Scedosporium/Pseudallescheria infection due to Pseudallescheria boydii sensu stricto after lung transplantation in a patient with cystic fibrosis. Dissemination occurred under voriconazole. Despite surgery and combination therapy with voriconazole, caspofungin, and terbinafine, the patient died 8 months after transplantation. Previously reported cases are reviewed.

The colonization of airways by filamentous fungi and the development of respiratory infections require some predisposing factors as encountered in patients with cystic fibrosis (CF). Indeed, the defective mucociliary clearance which characterizes the disease is associated with local immunological disorders. In addition, the prolonged therapy with antibiotics and the use of corticosteroid treatments also facilitate fungal growth. An important fungal biota has been described in respiratory secretions of patients suffering from CF. Aspergillus fumigatus, Scedosporium apiospermum and Aspergillus terreus for filamentous fungi and Candida albicans for yeasts are the main fungal species associated with CF. Although less common, several fungal species including Aspergillus flavus and Aspergillus nidulans may be isolated transiently from CF respiratory secretions, while others such as Exophiala dermatitidis and Scedosporium prolificans may chronically colonize the airways. Moreover, some of them like Penicillium emersonii and Acrophialophora fusispora are encountered in humans almost exclusively in the context of CF. As fungal complications in CF patients are essentially caused by filamentous fungi the present review will not include works related to yeasts. In CF patients, fungi may sometimes be responsible for deterioration of lung function, as occurs in allergic broncho-pulmonary aspergillosis (ABPA) which is the most common fungal disease in this context. Additionally, although the clinical relevance of the fungal airway colonization is still a matter of debate, filamentous fungi may contribute to the local inflammatory response, and therefore to the progressive deterioration of the lung function.

Polymorphism of forty-seven sequential clinical isolates from 3 patients with an aspergilloma was analyzed. DNA from each isolate was digested with EcoRI and hybridized in Southern blots with a 32P-labeled nonribosomal DNA repetitive sequence. Most isolates from each patient displayed the same hybridization pattern. Southern blot patterns obtained with DNA repetitive sequences can be used to type clinical isolates of Aspergillus fumigatus and have shown that aspergilloma patients are most probably infected by a single strain.