Sterol Composition of Clinically Relevant Mucorales and Changes Resulting from Posaconazole Treatment

Mucorales are fungi with increasing importance in the clinics. Infections take a rapidly progressive course resulting in high mortality rates. The ergosterol biosynthesis pathway and sterol composition are of interest, since they are targeted by currently applied antifungal drugs. Nevertheless, Mucorales often exhibit resistance to these drugs, resulting in therapeutic failure. Here, sterol patterns of six clinically relevant Mucorales (Lichtheimia corymbifera, Lichtheimia ramosa, Mucor circinelloides, Rhizomucor pusillus, Rhizopus arrhizus, and Rhizopus microsporus) were analysed in a targeted metabolomics fashion after derivatization by gas chromatography-mass spectrometry. Additionally, the effect of posaconazole (POS) treatment on the sterol pattern of R. arrhizus was evaluated. Overall, fifteen different sterols were detected with species dependent variations in the total and relative sterol amount. Sterol analysis from R. arrhizus hyphae confronted with sublethal concentrations of posaconazole revealed the accumulation of 14-methylergosta-8,24-diene-3,6-diol, which is a toxic sterol that was previously only detected in yeasts. Sterol content and composition were further compared to the well-characterized pathogenic mold Aspergillus fumigatus. This work contributes to a better understanding of the ergosterol biosynthesis pathway of Mucorales, which is essential to improve antifungal efficacy, the identification of targets for novel drug design, and to investigate the combinatorial effects of drugs targeting this pathway

Improving outcome of fungal diseases - Guiding experts and patients towards excellence

Invasive fungal infections are on the rise and during recent years understanding the epidemiology of fungal infections improved. Over 1 billion people are affected and 25 million patients are at imminent risk of severe organ damage or death due to fungal infection. The European Confederation of Medical Mycology (ECMM), founded in 1993, is the roof organisation of 23 National Medical Mycology Societies in Europe. ECMM fights fungal infections at various levels, by creating and distributing scientific knowledge and promoting scientific exchange. In response to the increasing prevalence and management complexity of invasive fungal infections, ECMM recently launched three additional initiatives (). (i) ECMM together with other European infectious diseases societies created a comprehensive set of European guidelines for the diagnostic and therapeutic management of invasive fungal infections. (ii) ECMM founded the ECMM Academy awarding fellow status (FECMM) to outstanding researchers who advanced medical mycology. The academy aims at strengthening networking activities between these researchers. (iii) Centres throughout the world can apply for ECMM Excellence Center Status. Following such application on site auditing of up to three levels of mycological work (clinical, microbiological, epidemiological/clinical trials) evaluates the excellence of a centre along predefined criteria. All three initiatives share a common ambition; they aim at improving outcome of fungal diseases through guiding experts and patients towards excellence. Acknowledging fungal infections as a global problem, all three initiatives explicitly reach out beyond European borders

Recent Increase in the Prevalence of Fluconazole-Non-susceptible Candida tropicalis Blood Isolates in Turkey: Clinical Implication of Azole-Non-susceptible and Fluconazole Tolerant Phenotypes and Genotyping

WOS: 000581278900001PubMed: 33123116Candida tropicalis is the fourth leading cause of candidemia in Turkey. Although C. tropicalis isolates from 1997 to 2017 were characterized as fully susceptible to antifungals, the increasing global prevalence of azole-non-susceptible (ANS) C. tropicalis and the association between high fluconazole tolerance (HFT) and fluconazole therapeutic failure (FTF) prompted us to re-evaluate azole susceptibility of C. tropicalis in Turkey. in this study, 161 C. tropicalis blood isolates from seven clinical centers were identified by ITS rDNA sequencing, genotyped by multilocus microsatellite typing, and tested for susceptibility to five azoles, two echinocandins, and amphotericin B (AMB); antifungal resistance mechanisms were assessed by sequencing of ERG11 and FKS1 genes. the results indicated that C. tropicalis isolates, which belonged to 125 genotypes grouped into 11 clusters, were fully susceptible to echinocandins and AMB; however, 18.6% of them had the ANS phenotype but only two carried the ANS-conferring mutation (Y132F). HFT was recorded in 52 isolates, 10 of which were also ANS. Large proportions of patients infected with ANS and HFT isolates (89 and 40.7%, respectively) showed FTF. Patients infected with azole-susceptible or ANS isolates did not differ in mortality, which, however, was significantly lower for those infected with HFT isolates (P = 0.007). There were significant differences in mortality (P = 0.02), ANS (P = 0.012), and HFT (P = 0.007) among genotype clusters. the alarming increase in the prevalence of C. tropicalis blood isolates with ANS and HFT in Turkey and the notable FTF rate should be a matter of public health concern.Major National R&D Projects of the National Health Department [2018ZX10101003]; National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [31770161]; Shanghai Science and Technology CommitteeShanghai Science & Technology Committee [17DZ2272900, 14495800500]; Shanghai Municipal Commission of Health and Family Planning [2017ZZ01024-001]; Shanghai Sailing Program [19YF1448000]; Chinese Academy of Engineering [2019-XY-33]This work was supported by the Major National R&D Projects of the National Health Department (2018ZX10101003), National Natural Science Foundation of China (31770161), Shanghai Science and Technology Committee (17DZ2272900 and 14495800500), Shanghai Municipal Commission of Health and Family Planning (2017ZZ01024-001), Shanghai Sailing Program (19YF1448000), and the Chinese Academy of Engineering (2019-XY-33)

Multicenter Comparison of the ISO Standard 20776-1 and the Serial 2-Fold Dilution Procedures To Dilute Hydrophilic and Hydrophobic Antifungal Agents for Susceptibility Testing ▿ †

A multicenter study was conducted to assess the accuracy of the ISO standard 20776-1 and the serial 2-fold dilution procedures for antifungal susceptibility testing. Fluconazole trays can be accurately prepared by following ISO and serial dilution schemes. However, itraconazole trays showed a significant lack of reproducibility that was independent of which method was followed

EQUAL Candida Score: An ECMM score derived from current guidelines to measure QUAlity of Clinical Candidaemia Management

Candida species frequently cause blood stream infections and are reported to be the third to tenth most commonly isolated pathogens. Guidelines and standardised treatment algorithms provided by professional organisations aim to facilitate decision-making regarding diagnosis, management and treatment of candidaemia. In routine clinical practise, however, it may be challenging to comply with these guidelines. The reasons include lack of familiarity or feasibility to adherence, but also their length and complexity. There is no tool to measure guideline adherence currently. To provide such a tool, we reviewed the current guidelines provided by the European Society for Clinical Microbiology and Infectious Diseases (ESCMID) and by the Infectious Diseases Society of America (IDSA), and selected the strongest recommendations for management quality as the bases for our scoring tool. Factors incorporated were diagnostic (blood cultures, echocardiography, ophthalmoscopy, species identification) and follow-up procedures (repeat blood cultures until negative result) as well as key treatment parameters (echinocandin treatment, step down to fluconazole depending on susceptibility result, CVC removal). The EQUAL Candida Score weighs and aggregates factors recommended for the ideal management of candidaemia and provides a tool for antifungal stewardship as well as for measuring guideline adherence.status: publishe

Development and validation of the European QUALity (EQUAL) score for mucormycosis management in haematology

Background: Mucormycosis is a life-threatening infection in immunocompromised patients and in haematological malignancy patients in particular. Objectives: Our aim was to develop and evaluate a scoring tool to measure adherence to current guidelines for mucormycosis. Methods: Current guidelines of scientific societies on mucormycosis management were reviewed. We assembled diagnostic, treatment and follow-up milestones and designed the EQUAL Mucormycosis Score. The EQUAL Mucormycosis Score was evaluated in the ECMM Excellence Centres. Results: An 18-item tool with one to three points per item resulted in a maximum achievable score depending on disease complexity and ranging from 25 to 32 points. Given variable patient disease course, the diagnostic score is higher in patients with positive fungal culture and biopsy, thus reflecting more decision points and higher management complexity. Eleven patients from two centres were included during the study period. A total of 200 EQUAL Mucormycosis Score points were achieved, which is 62.7% of the maximum EQUAL Mucormycosis Score of 319 points achievable in that cohort (median 18 points, range 7-27). The total score accomplished for diagnostic procedures was 112 of 165 points (67.9%), for first-line treatment 54 of 88 (61.4%) and for follow-up management 34 of 66 points (51.5%). Conclusions: The EQUAL Mucormycosis Score quantitates adherence to current guideline recommendations for mucormycosis management. With 62.7% of maximum achievable score points, a first result is obtained that may serve as a reference for future evaluations. It remains to be shown whether guideline adherence and mortality rates correlate

Multicentre validation of a EUCAST method for the antifungal susceptibility testing of microconidia-forming dermatophytes

OBJECTIVES: Terbinafine resistance is increasingly reported in Trichophyton, rendering susceptibility testing particularly important in non-responding cases. We performed a multicentre evaluation of six EUCAST-based methods. METHODS: Ten laboratories susceptibility tested terbinafine, itraconazole, voriconazole and amorolfine against a blinded panel of 38 terbinafine WT and target gene mutant isolates. E.Def 9.3.1 modifications included: medium with/without addition of chloramphenicol and cycloheximide (CC), incubation at 25°C to 28°C for 5-7 days and three MIC endpoints [visually and spectrophotometrically (90%/50% inhibition)], generating 7829 MICs. Quality control (QC) strains were Aspergillus flavus ATCC 204304 and CNM-CM1813. Eyeball, ECOFFinder (where ECOFF stands for epidemiological cut-off) and derivatization WT upper limits (WT-ULs), very major errors (VMEs; mutants with MICs ≤WT-ULs) and major errors (MEs; WT isolates with MICs >WT-ULs) were determined. RESULTS: MICs fell within the QC ranges for ATCC 204304/CNM-CM1813 for 100%/96% (voriconazole) and 84%/84% (itraconazole), respectively. Terbinafine MICs fell within 0.25-1 mg/L for 96%/92%, suggesting high reproducibility. Across the six methods, the number of terbinafine MEs varied from 2 to 4 (2.6%-5.2%) for Trichophyton rubrum and from 0 to 2 (0%-2.0%) for Trichophyton interdigitale. Modes for WT and mutant populations were at least seven 2-fold dilutions apart in all cases. Excluding one I121M/V237I T. rubrum mutant and two mixed WT/mutant T. interdigitale specimens, the numbers of VMEs were as follows: T. rubrum: CC visual, 1/67 (1.5%); CC spectrophotometric 90% inhibition, 3/59 (5.1%); and CC spectrophotometric 50% inhibition, 1/67 (1.5%); and T. interdigitale: none. Voriconazole and amorolfine MICs were quite uniform, but trailing growth complicated determination of itraconazole visual and spectrophotometric 90% inhibition MIC. CONCLUSIONS: Although none of the laboratories was experienced in dermatophyte testing, error rates were low. We recommend the CC spectrophotometric 50% inhibition method and provide QC ranges and WT-ULs for WT/non-WT classification.status: publishe

Low level of antifungal resistance of Candida glabrata blood isolates in Turkey: Fluconazole minimum inhibitory concentration and FKS mutations can predict therapeutic failure

Background Candida glabratais the third leading cause of candidaemia in Turkey; however, the data regarding antifungal resistance mechanisms and genotypic diversity in association with their clinical implication are limited. Objectives To assess genotypic diversity, antifungal susceptibility and mechanisms of drug resistance ofCglabratablood isolates and their association with patients' outcome in a retrospective multicentre study. Patients/Methods Isolates from 107 patients were identified by ITS sequencing and analysed by multilocus microsatellite typing, antifungal susceptibility testing, and sequencing ofPDR1andFKS1/2hotspots (HSs). Results Candida glabrataprevalence in Ege University Hospital was twofold higher in 2014-2019 than in 2005-2014. Six of the analysed isolates had fluconazole MICs >= 32 mu g/mL; of them, five harboured uniquePDR1mutations. Although echinocandin resistance was not detected, three isolates had mutations in HS1-Fks1 (S629T, n = 1) and HS1-Fks2 (S663P, n = 2); one of the latter was also fluconazole-resistant. All patients infected with isolates carrying HS-FKSmutations and/or demonstrating fluconazole MIC >= 32 mu g/mL (except one without clinical data) showed therapeutic failure (TF) with echinocandin and fluconazole; seven such isolates were collected in Ege (n = 4) and Gulhane (n = 3) hospitals and six detected recently. Among 34 identified genotypes, none were associated with mortality or enriched for fluconazole-resistant isolates. Conclusion Antifungal susceptibility testing should be supplemented with HS-FKSsequencing to predict TF for echinocandins, whereas fluconazole MIC >= 32 mu g/mL may predict TF. Recent emergence ofC glabrataisolates associated with antifungal TF warrants future comprehensive prospective studies in Turkey