Description d'une nouvelle espèce pathogène responsable de mucormycose

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Heat inactivation of monkeypox virus

Different kinds of media spiked with monkeypox virus (MPXV) were subjected to heat inactivation at different temperatures for various periods of time. The results showed that MPXV was inactivated in less than 5 min at 70 °C and less than 15 min at 60 °C, with no difference between viruses from the West African and Central African clades. The present findings could help laboratory workers to manipulate MPXV in optimal biosafety conditions and improve their protocols

Misidentification of Saprochaete clavata as Magnusiomyces capitatus in clinical isolates: utility of internal transcribed spacer sequencing and matrix-assisted laser desorption ionization-time of flight mass spectrometry and importance of reliable databases

International audienceSaprochaete clavata and Magnusiomyces capitatus are human pathogens that are frequently mistaken for each other due to their similar phenotypes and erroneous or limited databases. Based on internal transcribed spacer (ITS) sequences, we propose species-specific carbon assimilation patterns and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) fingerprints that enable the identification of S. clavata, M. capitatus, and Galactomyces candidus to the species level

Molecular and phenotypic evaluation of Lichtheimia corymbifera (formerly Absidia corymbifera) complex isolates associated with human mucormycosis: rehabilitation of L. ramosa.

International audienceThirty-eight isolates (including 28 isolates from patients) morphologically identified as Lichtheimia corymbifera (formerly Absidia corymbifera) were studied by sequence analysis (analysis of the internal transcribed spacer [ITS] region of the ribosomal DNA, the D1-D2 region of 28S, and a portion of the elongation factor 1alpha [EF-1alpha] gene). Phenotypic characteristics, including morphology, antifungal susceptibility, and carbohydrate assimilation, were also determined. Analysis of the three loci uncovered two well-delimited clades. The maximum sequence similarity values between isolates from both clades were 66, 95, and 93% for the ITS, 28S, and EF-1alpha loci, respectively, with differences in the lengths of the ITS sequences being detected (763 to 770 bp for isolates of clade 1 versus 841 to 865 bp for isolates of clade 2). Morphologically, the shapes and the sizes of the sporangiospores were significantly different among the isolates from both clades. On the basis of the molecular and morphological data, we considered isolates of clade 2 to belong to a different species named Lichtheimia ramosa because reference strains CBS 269.65 and CBS 270.65 (which initially belonged to Absidia ramosa) clustered within this clade. As neotype A. corymbifera strain CBS 429.75 belongs to clade 1, the name L. corymbifera was conserved for clade 1 isolates. Of note, the amphotericin B MICs were significantly lower for L. ramosa than for L. corymbifera (P < 0.005) but were alway

Heat inactivation of monkeypox virus

International audienceDifferent kinds of media spiked with monkeypox virus (MPXV) were subjected to heat inactivation at different temperatures for various periods of time. The results showed that MPXV was inactivated in less than 5 min at 70 °C and less than 15 min at 60 °C, with no difference between viruses from the West African and Central African clades. The present findings could help laboratory workers to manipulate MPXV in optimal biosafety conditions and improve their protocols

Successful Triple Combination Therapy of Disseminated Absidia corymbifera Infection in an Adolescent With Osteosarcoma

International audienceMucormycosis are opportunistic infections mostly observed in immunocompromised patients. We report the case of a 13-year-old girl who suffered a systemic mucormycosis without presenting the usual risk factors. She was undergoing antineoplastic chemotherapy for advanced osteosarcoma of the femur with an uncommunicative pathologic fracture and pulmonary metastasis. Absidia corymbifera was isolated from skin lesions at the primary tumor site. She subsequently developed fungal pulmonary localizations and blood vessel thrombosis. Surgical treatment together with systemic, high doses of liposomal amphotericin B, posaconazole, and caspofungin cured the local infection and controlled systemic lesions. Unfortunately, the break in chemotherapy led to pulmonary metastasis progression

Comparison of Microsatellite Length Polymorphism and Multilocus Sequence Typing for DNA-Based Typing of Candida albicans▿

For genotyping Candida albicans isolates, two PCR-based methods have recently emerged: multilocus sequence typing (MLST), based on the sequence of selected genes, and microsatellite length polymorphism (MLP), based on the length of PCR products containing variable numbers of short DNA repeats. To compare the two methods in their abilities to differentiate and group C. albicans isolates, we selected 50 independent isolates collected at the National Reference Center for Mycoses and Antifungals. MLST typing was performed using sequencing of seven loci as described at http://test1.mlst.net. The MLP method consisted of a single multiplex PCR testing three different loci. Dendrograms were constructed by the unweighted pair group cluster method with Euclidean metric for both methods. The correlation between the distance matrices was performed with a Mantel test tested with 1,000 random permutations. The sensitivity and specificity of the MLP typing system were determined after allocating MLST groups for the greater number of isolates of each distinct MLP group. The discriminatory power index was >0.99, and the distances between the isolates were highly correlated with both systems. The Mantel coefficient and the Pearson product-moment correlation coefficient were 35,699 and 0.32, respectively (P ≤ 1.2 × 10−6). Using MLP, the average specificity and sensitivity of clustering compared to MLST were 83% and 73%, respectively, when the singletons were excluded. The two methods are similarly discriminatory and can be interchangeable depending on the objectives. MLP is less expensive and faster than MLST. However, MLST is currently more accurate and additional standardization is needed for MLP

In Vitro Susceptibility to Posaconazole of 1,903 Yeast Isolates Recovered in France from 2003 to 2006 and Tested by the Method of the European Committee on Antimicrobial Susceptibility Testing▿

The posaconazole MIC90 for 1,903 yeast isolates from France was 1 μg/ml (range, ≤0.015 to 8 μg/ml). Ninety percent of isolates with fluconazole MICs of ≥8 μg/ml (n = 509) and 90% of those with voriconazole MICs of ≥2 μg/ml (n = 80) were inhibited by 2 and 8 μg/ml of posaconazole, respectively