BACKGROUND: Geotrichum is a genus of fungi found in different habitats throughout the world. Although Geotrichum and its related species have been extensively reclassified and taxonomically revised, it is still the target for many researches.
RESULTS: In this study, phenotypic and molecular genetics comparisons were performed between Geotrichum candidum and Geotrichum silvicola. Mitis Salivarius Agar was used as the growing medium for the phenotypic comparison study, which was carried out at two temperatures (20-25 and 37 °C). For genotypic comparison, we compared the 18 S, ITS, and 28 S sequences of universal DNA barcode regions of both species. Important findings on the new culture media for fungal isolation were revealed by the results. The phenotypic variation between the two species\' colonies, including their shapes, sizes, textures and growth rates, were strikingly different. DNA sequences of both species showed that pairwise identities of the species were 99.9% for 18 S, 100% for ITS and 99.6% for 28 S regions.
CONCLUSIONS: Contrary to what is commonly seen, the results showed that 18 S, ITS and 28 S failed to discriminate the species. The first investigation into the performance of Mitis Salivarius Agar as a fungus culture medium is reported in this work, and proved its efficiency. Additionally, this is the first study to compare G. candidum with G. silvicola by means of both phenotypic and genotypic analysis.

Malignant external otitis (MEO) has a frequent bacterial origin, but we are currently witnessing the emergence of fungal agents, which poses difficulties in diagnosis and management. The aim of our work is to analyze the epidemiological and clinical profile of fungal MEO and to study the antifungal susceptibility of fungi involved. Our study is retrospective collecting 43 patients treated for fungal MEO between 2010 and 2019. Clinical, biological, and radiological data were collected from patient hospitalization records. Identification of yeasts was done by YST vitek®2 card. The antifungal susceptibility testing was performed for yeasts by the AST vitek®2 card and for other fungi by the E-test technique. The average age was 66 (± 12) years. We noted a male predominance in 63 % (n=27). Diabetes was found in 86%. Otalgia was a constant symptom. Cranial nerve palsies were observed in 16% (n=7) of cases. CT showed bone lysis in 74% (n=31>) of cases and Tc99 bone scintigraphy revealed hyperfixation in 100% (n=43) of cases. Candida spp. (n=21), Aspergillus spp. (n=18), and Geotrichum capitatum (n=2) were isolated. No resistance to antifungals has been demonstrated for Candida yeasts. Geotrichum capitatum isolates were resistant to fluconazole and caspofungin. Aspergillus isolates were resistant to amphotericin B and caspofungin in 50% (n=9) and 72% (n=12) of cases, respectively. Our study proves the predominance of Candida yeasts and Aspergillus as the fungal agents involved in MOE. Mycological diagnosis allows the identification and antifungal susceptibility testing. Thus, it allows using of the appropriate antifungal treatment and improves the prognosis of the disease.

OBJECTIVE: Geotrichum spp can be responsible for severe infections in immunocompromised patients. We aim to describe Geotrichum-related infections in the ICU and to assess risk factors of mortality.
METHODS: Retrospective multicentre study, conducted in 14 French ICUs between 2002 and 2018, including critically ill adult patients with proven or probable infection related to Geotrichum species. Data were obtained from the medical charts.
RESULTS: Thirty-six patients, median age 60 years IQR [53; 66] were included. Most of the patients had haematological malignancies (78%). The reason for ICU admission was shock in half of the patients (n = 19, 53%) and respiratory failure in thirteen patients (36%). Median SOFA score was 8.5 IQR [7; 15]. Time between ICU admission and fungal diagnosis was 2.5 days [-1; 4]. Infection was disseminated in 27 (75%) patients with positive blood cultures in 25 patients (69%). Thirty patients (83%) received curative antifungal treatment in the ICU, in a median time of 1 day [0;1] after ICU admission. Twenty-four patients (67%) died in the ICU and hospital mortality rate was 69%. The number and extent of organ failures, as represented by SOFA score, were associated with mortality.
CONCLUSIONS: This study demonstrates poor outcome in critically ill patients with Geotrichum-related infections, which encourages a high level of suspicion.

In recent years, the incidence of superficial fungal infections involving nondermatophytic and noncandidal fungi increased considerably. The objective of this work was to analyze the epidemiological, clinical and mycological fungal infections due to nondermatophytic and noncandidal fungi diagnosed in the laboratory of parasitology-mycology of Le Dantec hospital in Dakar. With a retrospective study of the various cases of nondermatophytic and noncandidal fungi isolated in the laboratory of parasitology-mycology during the period of November 2013 to December 2014, we collected 22 cases of infections in 11 men and 11 women; age ranging from 17 to 75 years with a mean of 45.3 years (sex ratio=1): eight cases of intertrigo, seven cases of onychomycosis, four cases of palmoplantar keratoderma (KPP), a case of onychomycosis associated with interdigital intertrigo, a case of infectious myositis and one case of African histoplasmosis. We have isolated and identified a total of 22 nondermatophytic and noncandidal fungi: ten Fusarium, five Trichosporon, two Chrysosporium, two Geotrichum, one Rhodotorula, one Neoscytalidium dimidiatum and one Histoplasma capsulatum var. duboisii. So we are seeing the emergence of nondermatophytic and noncandidal increasingly isolated from superficial and local lesions. These fungi, generally contaminants or commensal, cause a problem regarding their direct involvement in pathological processes in which they are isolated. So we should respect the recommendations proposed for their involvement in pathological processes and, by a collaboration between clinician and biologist, demonstrate their real involvement through effective, targeted treatment.

The aim of this work was the genetic characterization at the strain level of 39 presumed Geotrichum candidum isolates isolated throughout the artisanal manufacturing and ripening of Armada cheese and tentatively identified at genus and/or species level by phenotypic characteristics. The molecular identification of the strains included among others the amplification and sequencing of the D1/D2 domains of the 26S rRNA gene. A restriction fragment length polymorphism (RFLP) analysis with the ITS1-5.8S-ITS2 PCR amplicons and a randomly amplified polymorphic DNA (RAPD) analysis with five different primers were carried out. The bands pattern profile obtained through RFLP by enzymatic restriction with HinfI was the same for all the strains studied, which confirmed the classification of the strains at species level. A RAPD-PCR analysis with three different primers was applied to assess the intraspecific diversity, in this way 16 band profiles were obtained for the 39 strains studied by the combined use of primers Ari1 and Omt1. This study contributes to know the occurrence and genotypic biodiversity of G. candidum in Armada cheese.

We report herein synthesis and antimicrobial activity of a series of N,N-dibenzyl-cyclohexane-1,2-diamine derivatives. In order to study the structure-activity relationship of substituted dibenzyl-cyclohexane-1,2-diamine derivatives, 44 structurally diverse compounds were synthesized and tested against Gram-positive and Gram-negative bacterial strains. Among them, compounds 17-20, 26, 37, 38 were found to be more active than tetracycline with MIC value ranging 0.0005-0.032 μg/mL and no hemolysis upto 1024 μg/mL in mammalian erythrocytes was observed. Some of the compounds have also shown very promising antifungal activity against Candida albicans, Candida glabrata and Geotrichum candidium.

The newly available AST-YS01 Vitek 2 cards were evaluated, and the results were compared with those obtained by the CLSI M27-A2 microdilution reference method. Clinical fungal isolates, including 614 isolates of Candida spp., 10 Cryptococcus neoformans isolates, 1 Geotrichum capitatum isolate, and 2 quality control strains, were tested for their susceptibilities to amphotericin B, fluconazole, and voriconazole using both methods. The majority of fungal isolates were susceptible to all antifungal agents tested: the MIC(90) values determined by the Vitek 2 and CLSI methods were 0.5 and 1 microg/ml, respectively, for amphotericin B; 8 and 16 microg/ml, respectively, for fluconazole; and <0.12 and 0.25 microg/ml, respectively, for voriconazole. Overall there was excellent categorical agreement (CA) between the methods (99.5% for amphotericin B, 92% for fluconazole, 98.2% for voriconazole), but discrepancies were observed within species. The CAs for fluconazole were low for Candida glabrata and Candida krusei when the results of the CLSI method at 48 h were considered. Moreover, the fully automated commercial system did not detect the susceptibility of Cryptococcus neoformans to voriconazole. The Vitek 2 system can be considered a valid support for antifungal susceptibility testing of fungi, but testing of susceptibility to agents not included in the system (e.g., echinocandins and posaconazole) should be performed with other methods.

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Laboratory investigations of the potential use of dried biomasses of Rhizopus stolonifer, Fusarium sp., Geotrichum sp., and Aspergillus fumigatus as biosorbents for the removal of bromophenol blue (BPB) dye from aqueous solutions were conducted. Kinetics studies indicated that the BPB dye uptake processes can be well described by the pseudo-second-order model. The fungal biomasses exhibited the highest dye biosorption at pH 2.0. The Langmuir adsorption model appears to fit the dye biosorption better than the Freundlich model, with maximum dye uptake capacities ranging from 526 to 1,111 mg/g, depending on the biomass used.

The activity of voriconazole was tested in vitro against 1996 clinical yeast isolates collected in 20 Italian microbiology laboratories. Voriconazole susceptibility testing was carried out with the broth microdilution (NCCLS M27-A2), Etest and disk diffusion methods. The minimum inhibitory concentrations at which 90% of the isolates were inhibited (MIC90) obtained with the NCCLS method were 0.03 mg/L for Candida albicans, 0.5 mg/L for Candida non-albicans and 0.25 mg/L for other genera; those obtained with Etesting were, respectively, 0.032 mg/L, 0.125 mg/L and 0.125 mg/L. With the disk diffusion method, the majority of isolates (92.3%) showed inhibition zone diameters between 21 mm and 40 mm. Using a tentative MIC cut-off of 1mg/L as indicative of in vitro susceptibility, 98.1% of the isolates tested in our study would be classified as susceptible, and only 28 (1.4%) of the isolates, with MICs higher than 2mg/L, would be classified as resistant to the drug. Our findings confirm the broad-spectrum in vitro activity of voriconazole against yeasts, including Candida species that are generally less susceptible to other azoles.