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Background Except for cryptococcosis, fungal infection of the central nervous system (FI-CNS) is a rare but severe complication. Clinical and radiological signs are non-specific, and the value of conventional mycological diagnosis is very low. This study aimed to assess the value of β1,3-D-glucan (BDG) detection in the cerebrospinal fluid (CSF) of non-neonatal non-cryptococcosis patients. Methods Cases associated with BDG assay in the CSF performed in 3 French University Hospitals over 5 years were included. Clinical, radiological, and mycological results were used to classify the episodes as proven/highly probable, probable, excluded, and unclassified FI-CNS. Sensitivity and specificity were compared to that calculated from an exhaustive review of the literature. Results In total, 228 episodes consisting of 4, 7, 177, and 40 proven/highly probable, probable, excluded, and unclassified FI-CNS, respectively, were analysed. The sensitivity of BDG assay in CSF to diagnose proven/highly probable/probable FI-CNS ranged from 72.7% [95% confidence interval {CI}: 43.4%‒90.2%] to 100% [95% CI: 51%‒100%] in our study and was 82% in the literature. For the first time, specificity could be calculated over a large panel of pertinent controls and was found at 81.8% [95% CI: 75.3%‒86.8%]. Bacterial neurologic infections were associated with several false positive results Conclusions Despite its sub-optimal performance, BDG assay in the CSF should be added to the diagnostic armamentarium for FI-CNS.

PCR-based methods applied to various body fluids emerged in recent years as a promising approach for the diagnosis of mucormycosis. In this study, we set up and assess the value of a qPCR to detect a wide variety of Mucorales species in a single tube. A pair of degenerated primers targeting the rDNA operon was used in a qPCR utilizing an intercalating fluorescent dye. Analytical assessment, using a wide variety of both Mucorales strains (8 genera, 11 species) and non-Mucorales strains (9 genera, 14 species), showed 100% sensitivity and specificity rates with a limit of detection at 3 rDNA copy/qPCR reaction. Subsequently, 364 clinical specimens from 166 at-risk patients were prospectively tested with the assay. All the seven patients classified as proven/probable mucormycosis using the EORTC-MSG criteria had a positive qPCR as well as a patient with a proven uncharacterized invasive mold infection. In addition, three out of seven patients with possible mold invasive infections had at least one positive qPCR test. Sensitivity was calculated between 73.33 and 100% and specificity between 98.10 and 100%. The qPCR method proposed showed excellent performances and would be an important adjunctive tool for the difficult diagnosis of mucormycosis diagnosis. Lay abstract qPCR-based diagnosis is the most reliable approach for mucormycosis. We set up a pan-Mucorales qPCR able to detect in a single reaction not less than 11 different species. Both analytical and clinical performances support its use in the clinical setting.

Invasive fungal infections (IFI) are an important cause of morbidity and mortality in children with leukaemia. International guidelines recommend a monotherapy for most IFI. The use of antifungal combination therapy (ACT) has been reported, but clinical data supporting these combinations are scarce, particularly in paediatrics.To describe, among patients treated in our department, the situations in which an ACT was used.Between January 2017 and December 2020, 239 patients (406 hospital stays) benefited from systemic antifungals. Among them, ACT was prescribed for 14 (5.9%) patients (13 leukaemia, 1 aplastic anaemia) corresponding to 16 (3.9%) hospital stays. IFI cases treated with ACT were mainly proven (n=9) or probable (n=4). Seven cases required admission to the intensive care unit. The most commonly used antifungal agents were liposomal amphotericin B (n=13), caspofungin (n=12) and voriconazole (n=9). In 13 cases, monotherapy was prescribed as first-line therapy and changed to an ACT for an uncontrolled infection. But in 3 cases, the ACT was started immediately. The response at 12 weeks after diagnosis of proven/probable IFI was successful in 12 cases (92.3%). The only IFI-related death was attributed to disseminated mucormycosis. ACT were generally well tolerated. In 4 cases, adverse events led to the discontinuation of the offending antifungal agent.This retrospective analysis of practices shows that the use of ACT in our paediatric haemato-oncology department is rare, and concerns the most severe cases and/or those not responding to the first line treatment. In most cases, ACT was efficient and well tolerated.

The major challenge of the COVID-19 health crisis is to identify the factors of susceptibility to SARS-Cov2 in order to adapt the recommendations to the populations and to reduce the risk of getting COVID-19 to the most vulnerable people especially those having chronic respiratory diseases including cystic fibrosis (CF). Airway epithelial cells (AEC) are playing a critical role in the immune response and in COVID-19 severity. SARS-CoV-2 infects the airways through ACE2 receptor and the host protease TMPRSS2 was shown to play a major role in SARS-CoV-2 infectivity. Here, we show that the main component of P. aeruginosa flagella, ie. flagellin is able to increase TMPRSS2 expression in AEC, and even more in those deficient for CFTR. Importantly, this increased TMPRSS2 expression is associated with an increase in the level of SARS-CoV-2 infection. Considering the urgency of the health situation, this result is of major significance for patients with CF which are frequently infected and colonized by P. aeruginosa during the course of the disease.

International audience; Aspergillus fumigatus is an environmental filamentous fungus that can be pathogenic for humans, wherein it is responsible for a large variety of clinical forms ranging from allergic diseases to life-threatening disseminated infections. The contamination occurs by inhalation of conidia present in the air, and the first encounter of this fungus in the human host is most likely with the bronchial epithelial cells. Although alveolar macrophages have been widely studied in the Aspergillus-lung interaction, increasing evidence suggests that bronchial epithelium plays a key role in responding to the fungus. This review focuses on the innate immune response of the bronchial epithelial cells against A. fumigatus, the predominant pathogenic species. We have also detailed the molecular interactants and the effects of the different modes of interaction between these cells and the fungus.

Reference methods used to assess the drug susceptibilities of Aspergillus fumigatus isolates consisted of EUCAST and CLSI standardized broth microdilution techniques. Considering the increasing rate and the potential impact on the clinical outcome of azole resistance in A. fumigatus, more suitable techniques for routine testing are needed. The gradient concentration strip (GCS) method has been favorably evaluated for yeast testing. The aim of this study was to compare the CGS test with EUCAST broth microdilution for amphotericin B (AMB), posaconazole (PCZ), itraconazole (ITZ), voriconazole (VRZ), and isavuconazole (ISA). A total of 121 Aspergillus section Fumigati strains were collected, including 24 A. fumigatus sensu stricto strains that were resistant to at least one azole drug. MICs were determined using GCS and EUCAST methods. Essential agreement between the 2 methods was considered when MICs fell within ±1 dilution or ±2 dilutions of the 2-fold dilution scale. Categorical agreement was defined as the percentage of strains classified in the same category (susceptible, intermediate, or resistant) with both methods. Essential agreements with ±1 dilution and ±2 dilutions were 96.7, 93.4, 90.0, 89.3, and 95% and 100, 99.2, 100, 97.5, and 100% for AMB, PCZ, ITZ, VRZ, and ISA, respectively. Categorical agreements were 94.3, 86.1, 89.3, and 88.5% for AMB, PCZ, ITZ, and VRZ, respectively. Detection of resistance was missed with the GCS for one strain (4.1%) for PCZ and for 2 strains (8.3%) for ISA. Determination of ITZ MICs using the GCS allowed the detection of 91.7% of azole-resistant strains. The GCS test appears to be a valuable method for screening azole-resistant A. fumigatus clinical isolates.

PCR-based methods are a key tool for the diagnosis of toxoplasmosis in immunocompromised patients. Laboratory-developed protocols lack standardization. This study aimed to assess the performances of a commercial kit for the detection of Toxoplasma DNA in different specimens drawn from immunocompromised patients. This multicentric retrospective study included 227 DNA specimens (157 blood specimens, 22 bronchoalveolar fluid [BALF] specimens, 39 cerebrospinal fluid [CSF] specimens, and 9 miscellaneous specimens) collected between 2010 and 2015 from 126 immunocompromised patients. The specimens were selected based on previous laboratory-developed quantitative PCR (qPCR) analyses targeting either the rep529 element or the B1 gene, and the results were classified as positive, negative, and "negative of interest," where the latter was defined as representing either the last specimen with a negative result before a positive one or the first with a negative result following a positive result(s). All specimens were secondary tested using the Bio-Evolution Toxoplasma DNA assay targeting the T. gondii rep529 element. We found a 95.6% concordance rate for qualitative results obtained with laboratory-developed qPCR techniques and the commercial kit. The rate reached 99.3% in comparisons of rep529-based laboratory-developed PCR methods and the commercial kit. The quantifications obtained with the commercial kit and the rep529 laboratory-developed PCRs were in very good agreement. Sensitivity and specificity of the commercial kit were calculated at 98.8% and 100%, respectively. The Bio-Evolution Toxoplasma DNA assay appears to be a valuable method for the detection of Toxoplasma DNA in blood, BALF, and CSF specimens from immunocompromised patients.

To evaluate the in vitro susceptibility of Fusarium to isavuconazole, 75 clinical isolates were identified using matrix-assisted laser desorption ionization–time of flight mass spectrometry and then tested with a broth microdilution method (EUCAST) and the gradient concentration strip (GCS) technique. The activity of isavuconazole overall was shown to be limited, with an MIC 50 of >16 μg/ml, without significant differences between the species complexes.

Introduction Nous avons recemment montre que les cellules epitheliales bronchiques (CEB) etaient capables de memoriser une premiere rencontre avec un pathogene. Ce processus de memoire engendre une modulation de leur reponse inflammatoire lors d’un stimulus secondaire survenant 6 jours plus tard. L’utilisation d’inhibiteurs de methylation et d’acetylation d’histones suggerait l’implication de processus epigenetiques. Notre objectif, ici, a ete de rechercher les mecanismes epigenetiques, lies a l’etat de condensation de la chromatine, pouvant etre a l’origine de cette memoire immunitaire innee. Methodes Les CEB (lignee BEAS-2B) ont ete pre-exposees pendant 48 heures a un agoniste microbien, la flagelline de Pseudomonas aeruginosa, puis lavees et laissees au repos pendant 4 jours. L’ADN et l’ARN ont ete extraits, a J0, a 48 heures et apres les 4 jours de repos afin d’analyser d’une part les regions de la chromatine accessibles a la machinerie transcriptionnelle (Assay for Transposase-Accessible Chromatin sequencing ou ATAC-seq) et d’autre part l’expression des genes (microarray) des cellules exposees ou non a la flagelline. Resultats La pre-exposition des CEB a la flagelline module l’expression de 1598 et 2086 genes a J2 et a J6, respectivement. Parmi eux, 272 genes montrent une modification d’expression a J2 par la pre-stimulation avec la flagelline, qui se poursuit a J6. Les donnees de l’ATAC-seq indiquent que 688 loci, correspondants a des regions ouvertes sont presents a J2 et a J6 exclusivement dans les cellules exposees a la flagelline. L’analyse croisee des donnees du microarrays et de l’ATAC-seq montrent que l’expression de genes impliques dans la regulation de la reponse inflammatoire, tels que TNFAIP3 et de NFKBIA, est correlee a la presence de loci. Conclusion L’analyse du remodelage de la chromatine et du transcriptome nous a permis d’identifier l’impact a long terme d’une pre-exposition des CEB a un composant bacterien sur l’accessibilite de certaines regions d’ADN a la transcription et sur l’expression genique. Le role de facteurs de transcription sur ces modulations est en cours d’analyses.

Human bronchial epithelial cells play a key role in airway immune homeostasis. We hypothesized that these sentinel cells can remember a previous contact with pathogen compounds and respond nonspecifically to reinfection, a phenomenon called innate immune memory. We demonstrated that their pre-exposure to Pseudomonas aeruginosa flagellin modify their inflammatory response to a second, non-related stimulus, including live pathogens or lipopolysaccharide. Using histone acetyltransferase and methyltransferase inhibitors, we showed that this phenomenon relied on epigenetic regulation. This report is a major breakthrough in the field of multi-microbial respiratory tract infections, wherein control of inflammatory exacerbations is a major therapeutic issue.

PCR-based methods are a key tool for the diagnosis of toxoplasmosis in immunocompromised patients. Laboratory-developed protocols lack standardization. This study aimed to assess the performances of a commercial kit for the detection of Toxoplasma DNA in different specimens drawn from immunocompromised patients. This multicentric retrospective study included 227 DNA specimens (157 blood specimens, 22 bronchoalveolar fluid [BALF] specimens, 39 cerebrospinal fluid [CSF] specimens, and 9 miscellaneous specimens) collected between 2010 and 2015 from 126 immunocompromised patients. The specimens were selected based on previous laboratory-developed quantitative PCR (qPCR) analyses targeting either the rep529 element or the B1 gene, and the results were classified as positive, negative, and “negative of interest,” where the latter was defined as representing either the last specimen with a negative result before a positive one or the first with a negative result following a positive result(s). All specimens were secondary tested using the Bio-Evolution Toxoplasma DNA assay targeting the T. gondii rep529 element. We found a 95.6% concordance rate for qualitative results obtained with laboratory-developed qPCR techniques and the commercial kit. The rate reached 99.3% in comparisons of rep529-based laboratory-developed PCR methods and the commercial kit. The quantifications obtained with the commercial kit and the rep529 laboratory-developed PCRs were in very good agreement. Sensitivity and specificity of the commercial kit were calculated at 98.8% and 100%, respectively. The Bio-Evolution Toxoplasma DNA assay appears to be a valuable method for the detection of Toxoplasma DNA in blood, BALF, and CSF specimens from immunocompromised patients.