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Molecular diagnostic assays can accelerate the diagnosis of fungal infections and subsequently improve patient outcomes. In particular, the detection of infections due to Mucorales is still challenging for laboratories and physicians. The aim of this study was to evaluate a probe-based Mucorales-specific real-time PCR assay (Muc18S) using tissue and serum samples from patients suffering from invasive mucormycosis (IMM). This assay can detect a broad range of clinically relevant Mucorales species and can be used to complement existing diagnostic tests or to screen high-risk patients. An advantage of the Muc18S assay is that it exclusively detects Mucorales species allowing the diagnosis of Mucorales DNA without sequencing within a few hours. In paraffin-embedded tissue samples this PCR-based method allowed rapid identification of Mucorales in comparison with standard methods and showed 91 % sensitivity in the IMM tissue samples. We also evaluated serum samples, an easily accessible material, from patients at risk from IMM. Mucorales DNA was detected in all patients with probable/proven IMM (100 %) and in 29 % of the possible cases. Detection of IMM in serum could enable an earlier diagnosis (up to 21 days) than current methods including tissue samples, which were gained mainly post-mortem. A screening strategy for high-risk patients, which would enable targeted treatment to improve patient outcomes, is therefore possible.

Invasive aspergillosis (IA) is associated with significant morbidity and mortality, and, among other factors, this is due to a delay in diagnosis performed with conventional techniques. A prospective, multicentre study was conducted to evaluate the efficacy of Aspergillus DNA screening in the early diagnosis of IA. Patients undergoing haematopoietic stem cell transplantation or chemotherapy for acute leukaemia were enrolled for biomarker screening. Three centres applied the same protocol for in-house PCR, which was compliant with the European Aspergillus PCR Initiative recommendations, to guarantee the highest diagnostic standards. Two thousand one hundred and twenty-eight sera from 213 patients were investigated and stratified according to the revised European Organization for the Research and Treatment of Cancer/Mycoses Study Group criteria for invasive fungal disease. The incidence rates of probable and possible IA were 18% and 38%, respectively. The sensitivity, specificity and positive predictive value (PPV) of PCR were superior in antifungal drug-naive patients, being 71.4%, 92.3%, and 62.5%, respectively. The last of these key performance indicators (PPV) was moderate in patients receiving primary prophylaxis, at 5.4%. Negative predictive values for both strategies applied were 100% with and 98.3% without antifungal mould prophylaxis. PCR has the potential to play a decisive role in the diagnosis and management of Aspergillus infections in centres not applying primary antifungal mould prophylaxis.

Prompt diagnosis of invasive fungal infections (IFI) remains a challenge. (1,3)β-D-glucan detection in bronchoalveolar lavage (BAL) fluid by Fungitell assay aims to further improve upon the test's utility by directly applying it to specimens from the target organ.A prospective multicenter analysis of the Fungitell assay was performed on BAL and serum samples obtained from nonselected solid-organ transplantation patients suffering from probable, proven or no IFI according to the revised criteria of the European Organisation for Research and Treatment of Cancer / Mycosis Study Group.Two hundred thirty-three BAL and 109 serum specimens from 135 patients with proven, probable, or no IFI were tested. Based on a 100 pg/mL: cutoff per test sensitivity, specificity, positive and negative predictive values were 79.2%, 38.5%, 27.6%, and 86.3% in BALs and 79.2%, 81.8%, 69.2%, and 83.1% in sera investigated.The accuracy of the (1,3)β-D-glucan test is marginal so that its utility as a clinical test for early diagnosis of IFI is questionable in the lung transplant population. Although the high negative predictive value of the Fungitell assay in both, BALs and sera, may support exclusion of pulmonary IFI in solid-organ transplantation patients, the low positive predictive value limits its utility as a screening tool for early diagnosis of IFI.

For antifungal susceptibility testing of nonsporulating or poorly sporulating dermatophytes, a fragmented-mycelium inoculum preparation method was established and compared to broth microdilution testing according to CLSI and EUCAST guidelines. Moreover, the in vitro activity of new antifungal agents against dermatophytes was evaluated. Agreement between the mycelial inoculum method and the CLSI broth microdilution method was high (93% to 100%). Echinocandins (minimal effective concentration [MEC], ≤0.5 mg/liter) and posaconazole (MIC, ≤3.00 mg/liter) showed good activity against all tested dermatophytes.

International audience; As a result of fundamental changes in the International Code of Nomenclature on the use of separate names for sexual and asexual stages of fungi, generic names of many groups should be reconsidered. Members of the ECMM/ISHAM working group on Pseudallescheria/Scedosporium infections herein advocate a novel nomenclature for genera and species in Pseudallescheria, Scedosporium and allied taxa. The generic names Parascedosporium, Lomentospora, Petriella, Petriellopsis, and Scedosporium are proposed for a lineage within Microascaceae with mostly Scedosporium anamorphs producing slimy, annellidic conidia. Considering that Scedosporium has priority over Pseudallescheria and that Scedosporium prolificans is phylogenetically distinct from the other Scedosporium species, some name changes are proposed. Pseudallescheria minutispora and Petriellidium desertorum are renamed as Scedosporium minutisporum and S. desertorum, respectively. Scedosporium prolificans is renamed as Lomentospora prolificans.