27 research outputs found

    Common staining techniques for highlighting Acanthamoeba cysts

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    A 36-year-old woman returning from holiday in Portugal presented with bilateral ocular pain and acute visual loss. Eye examination revealed an inflammation in the anterior segment associated with corneal keratitis. During her trip, she wore contact lenses and rinsed the storage case using tap water. Corneal scrapings, contact lenses and cleaning solution from the case were inoculated onto agar plates supplemented with heat-inactivated bacteria. Bilateral Acanthamoeba keratitis was diagnosed, as microscopic examination of cultures from the last two samples revealed typical, spherical double-walled cystic structures (Fig. 1)

    Genomic Organization and Expression of Iron Metabolism Genes in the Emerging Pathogenic Mold

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    The ubiquitous mold is increasingly recognized as an emerging pathogen, especially among patients with underlying disorders such as immunodeficiency or cystic fibrosis (CF). Indeed, it ranks the second among the filamentous fungi colonizing the respiratory tract of CF patients. However, our knowledge about virulence factors of this fungus is still limited. The role of iron-uptake systems may be critical for establishment of infections, notably in the iron-rich environment of the CF lung. Two main strategies are employed by fungi to efficiently acquire iron from their host or from their ecological niche: siderophore production and reductive iron assimilation (RIA) systems. The aim of this study was to assess the existence of orthologous genes involved in iron metabolism in the recently sequenced genome of . At first, a tBLASTn analysis using iron-related proteins as query revealed orthologs of almost all relevant loci in the genome. Whereas the genes putatively involved in RIA were randomly distributed, siderophore biosynthesis and transport genes were organized in two clusters, each containing a non-ribosomal peptide synthetase (NRPS) whose orthologs in have been described to catalyze hydroxamate siderophore synthesis. Nevertheless, comparative genomic analysis of siderophore-related clusters showed greater similarity between and phylogenetically close molds than with species. The expression level of these genes was then evaluated by exposing conidia to iron starvation and iron excess. The expression of several orthologs of genes involved in siderophore-based iron uptake or RIA was significantly induced during iron starvation, and conversely repressed in iron excess conditions. Altogether, these results indicate that possesses the genetic information required for efficient and competitive iron uptake. They also suggest an important role of the siderophore production system in iron uptake by

    Successful treatment of a recurrent Aspergillus niger otomycosis with local application of voriconazole

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    Fungal otitis (otomycosis) is a common infection encountered by otolaryngologists. Nevertheless, its management can be challenging because of its high recurrence rate and of the limited therapeutic options. A 45-year-old woman suffered from recurrent otomycosis. The ineffectiveness of successive antibiotic cures and repeated topical treatments with nystatin and then with econazole cream led to perform microbiological analyses. Culture of ear swab grew Aspergillus niger. The use of a 1% voriconazole sterile solution previously validated for treatment of eye infections was considered after ensuring the absence of known ototoxic effects of the antifungal and of the excipients. The patient was advised to apply locally this voriconazole solution daily for 14 days (3 drops, 3-4 times a day). Full recovery was obtained at the end of the treatment, and no relevant side effects were noticed. More than one year after completion of therapy, there was no recurrence. Our observation shows that voriconazole 1% solution is an interesting option for treating otomycosis which failed to respond to usual therapeutic options. Further prospective studies are now warranted to confirm these findings

    Investigation of nosocomial pneumocystis infections: usefulness of longitudinal screening of epidemic and post-epidemic pneumocystis genotypes

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    BACKGROUND: Twenty-five patients, of whom 22 were renal transplant recipients, developed Pneumocystis jirovecii infections at the nephrology department of Reims University Hospital (France) from September 2008 to October 2009, whereas only four sporadic cases had been diagnosed in this department over the 14 previous years. AIM: This outbreak was investigated by analysing patient encounters and P. jirovecii types. METHODS: A transmission map was drawn up. P. jirovecii typing at DHPS, ITS and mtLSU rRNA sequences was performed in the patients of the cluster (18 patients with Pneumocystis pneumonia (PCP) and seven colonized patients), 10 unlinked control patients (six PCP patients and four colonized patients), as well as 23 other patients diagnosed with P. jirovecii (nine PCP patients and 14 colonized patients) in the same department over a three-year post-epidemic period. FINDINGS: Eleven encounters between patients harbouring the same types were observed. Three PCP patients and one colonized patient were considered as possible index cases. The most frequent types in the cluster group and the control group were identical. However, their frequency was significantly higher in the first than in the second group (P < 0.01). Identical types were also identified in the post-epidemic group, suggesting a second outbreak due to the same strain, contemporary to a disruption in prevention measures. CONCLUSIONS: These results provide additional data on the role of both PCP and colonized patients as infectious sources. Longitudinal screening of P. jirovecii types in infected patients, including colonized patients, is required in the investigation of the fungus\u27s circulation within hospitals

    Exophiala dermatitidis Revealing Cystic Fibrosis in Adult Patients with Chronic Pulmonary Disease

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    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

    Human cryptosporidiosis in immunodeficient patients in France (2015-2017)

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    Cryptosporidiosis is a common disease in children and immunodeficient individuals. In 2006, a national network was set up on the surveillance of human cryptosporidiosis in France. Since January 2015, the 41 tertiary care hospitals and the 3 private laboratories of the French National Network on the surveillance of human cryptosporidiosis have been able to declare confirmed cases of cryptosporidiosis online. Between 2015 and 2017, 210 cases of cryptosporidiosis were declared in immunodeficient patients in France; Cryptosporidium parvum and Cryptosporidium hominis represented 66% and 22% of cases, respectively. A peak was observed in autumn. Cryptosporidiosis occurred mainly in a context of solid organ transplantation (SOT) (49%) and of HIV infection (30%). In SOT recipients, cryptosporidiosis appeared more frequently in the first 6 months post transplantation. Regarding cases declared in SOT recipients, mycophenolate mofetil was used in 68%. A mortality rate of 6% was observed. Present results underline the importance of screening for cryptosporidiosis in immunocompromised patients suffering from diarrhea, especially in the course of major cell mediated immunodeficiency or even systematic screening before SOT. Exclusive Cryptosporidium free water feeding could be suggested during major cell mediated immunodeficiency

    Organization of Patient Management and Fungal Epidemiology in Cystic Fibrosis

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    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

    Rapid diagnostic tests relying on antigen detection from stool as an efficient point of care testing strategy for giardiasis and cryptosporidiosis? Evaluation of a new immunochromatographic duplex assay

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    Microscopy is the gold standard for the diagnosis of gastrointestinal parasites but is time-consuming and dependent on operator skills. Rapid diagnostic tests represent alternative methods but most evaluations have been conducted on a limited number of samples preventing their implementation in the clinical setting. We evaluated a new CE-IVD marked immunochromatographic assay (Crypto/Giardia K-SeT®, Coris Bioconcept) for the detection of G. intestinalis and Cryptosporidium spp. in 2 phases (retrospective and prospective) on a set of 482 stool samples including rare Cryptosporidium species. Besides G. intestinalis, this test could represent a rapid and reliable alternative to the modified Ziehl-Neelsen staining for the diagnosis of cryptosporidiosis (sensitivity/specificity were 89.2%/99.3% and 86.7%/100% for G. intestinalis and Cryptosporidium resp.), reducing diagnostic delays. Such strategy would also be time-saving by avoiding wet mount microscopy and concentrations steps, being particularly appropriate for laboratories having little expertise in microscopy or not able to implement molecular diagnostic methods

    Oxygen mobility in CeO2 and CexZr(1-x)O2 compounds: Study by CO transient oxidation and O-18/O-16 isotopic exchange

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    SSCI-VIDE+CARE+CDSInternational audienceCerium-zirconium mixed oxides (CexZr(1-x)O2), precalcined at 900 degrees C in dry air, were supplied by Rhodia Terres Rares as monophasic solid solutions. Introduction of some zirconium atoms in the ceria lattice by isomorphous substitution clearly influences the final properties of these materials as long as the cubic structure of ceria is maintained, Modifications in oxygen storage capacity (OSC measurements), redox properties (CO TPR), and oxygen exchange processes (TPIE) were studied. Ce0.63Zr0.37O2 was shown to have the most promising properties with-the largest OSC at 400 degrees C and the highest reactivity in O-2 exchange. All mixed oxides are able to exchange very large amounts of oxygen compared to ceria, implying the participation of bulk oxygen. Furthermore, on CexZr(1-x)O2 samples, oxygen is predominantly exchanged via a multiple heteroexchange mechanism involving surface dioxygen species as superoxides or peroxides

    Oxygen Mobility in CeO 2

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