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Subcutaneous phaeohyphomycosis is an implantation disease caused by melanized fungi and affect both immunocompetent as well as immunocompromised individuals. Diagnosis and treatment require proper isolation and accurate identification of the causative pathogen. We isolated a novel fungus from a case of subcutaneous phaeohyphomycosis in an immunocompetent patient. The 56-year-old patient suffered from a slowly progressive swelling on the metatarsophalangeal join of the left food. The isolated fungus lacked sporulation and sequences of the ribosomal operon did not match with any known species. In a multi-locus phylogenetic analysis involving five markers, the fungus formed a unique lineage in the order Pleosporales, family Trematosphaeriaceae. A new genus, Meanderella and a new species, Meanderella rijsii are here proposed to accommodate the clinical isolate. Whole genome analysis of M. rijsii revealed a number of genes that can be linked to pathogenicity and virulence. Further studies are however needed to understand the role of each gene in the pathogenic process and to determine the origin of pathogenicity in the family of Trematosphaeriaceae., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2022 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

This paper presents a case of disseminated sporotrichosis in a 13-year-old female, originating from a rural area in Minas Gerais state, Brazil. The patient was hospitalized in Santa Casa hospital of Belo Horizonte, with hyporexia, prostration, fever and disseminated ulcerative lesions, besides anemia, leucopenia and sepsis of probable cutaneous focus. The patient was admitted without proven immunosuppression. She was diagnosed with cutaneous-disseminated sporotrichosis. The drug therapy chosen was itraconazole during 12 months, leading to important clinical improvement and healing of cutaneous lesions.

Chromoblastomycosis is a mutilating infection of the skin and subcutaneous tissues caused by melanized fungi belonging to the order Chaetothyriales. Proven cases of the main agent, Fonsecaea pedrosoi are mainly limited to (sub)tropical, humid climates of Latin and Central America and the Caribbean. Fonsecaea monophora has a global distribution along the equator. Cases outside the (sub)tropics have thus far mostly been considered to have been imported, but here we report the first endemic case by F. monophora from Argentina. Patient was a 82-year-old rural female worker from Corrientes, a province with a dry continental climate.

Mycoses summarized in the hyalohyphomycosis group are heterogeneous, defined by the presence of hyaline (non-dematiaceous) hyphae. The number of organisms implicated in hyalohyphomycosis is increasing and the most clinically important species belong to the genera Fusarium, Scedosporium, Acremonium, Scopulariopsis, Purpureocillium and Paecilomyces. Severely immunocompromised patients are particularly vulnerable to infection, and clinical manifestations range from colonization to chronic localized lesions to acute invasive and/or disseminated diseases. Diagnosis usually requires isolation and identification of the infecting pathogen. A poor prognosis is associated with fusariosis and early therapy of localized disease is important to prevent progression to a more aggressive or disseminated infection. Therapy should include voriconazole and surgical debridement where possible or posaconazole as salvage treatment. Voriconazole represents the first-line treatment of infections due to members of the genus Scedosporium. For Acremonium spp., Scopulariopsis spp., Purpureocillium spp. and Paecilomyces spp. the optimal antifungal treatment has not been established. Management usually consists of surgery and antifungal treatment, depending on the clinical presentation., (© 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.)

These European Society for Clinical Microbiology and Infectious Diseases and European Confederation of Medical Mycology Joint Clinical Guidelines focus on the diagnosis and management of mucormycosis. Only a few of the numerous recommendations can be summarized here. To diagnose mucormycosis, direct microscopy preferably using optical brighteners, histopathology and culture are strongly recommended. Pathogen identification to species level by molecular methods and susceptibility testing are strongly recommended to establish epidemiological knowledge. The recommendation for guiding treatment based on MICs is supported only marginally. Imaging is strongly recommended to determine the extent of disease. To differentiate mucormycosis from aspergillosis in haematological malignancy and stem cell transplantation recipients, identification of the reverse halo sign on computed tomography is advised with moderate strength. For adults and children we strongly recommend surgical debridement in addition to immediate first-line antifungal treatment with liposomal or lipid-complex amphotericin B with a minimum dose of 5 mg/kg/day. Amphotericin B deoxycholate is better avoided because of severe adverse effects. For salvage treatment we strongly recommend posaconazole 4×200 mg/day. Reversal of predisposing conditions is strongly recommended, i.e. using granulocyte colony-stimulating factor in haematological patients with ongoing neutropenia, controlling hyperglycaemia and ketoacidosis in diabetic patients, and limiting glucocorticosteroids to the minimum dose required. We recommend against using deferasirox in haematological patients outside clinical trials, and marginally support a recommendation for deferasirox in diabetic patients. Hyperbaric oxygen is supported with marginal strength only. Finally, we strongly recommend continuing treatment until complete response demonstrated on imaging and permanent reversal of predisposing factors., (© 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.)

During the MICROMAT project, the fungal diversity of microbial mats growing in the benthic environment of Antarctic lakes was accessed for the discovery of novel antibiotics and anticancers. In all, 160 filamentous fungi belonging to fifteen different genera and 171 yeasts were isolated from 11 lakes, classified and cultivated in different media and at different temperatures. Filamentous fungi were then screened to discover novel antimicrobial and cytotoxic compounds. A total of 1422 extracts were prepared by solid phase extraction of the culture broths or by biomass solvent extraction. 47 (29%) filamentous fungi showed antimicrobial activity; most of them inhibited the growth of gram-positive Staphyloccus aureus (14%), gram-negative E. coli (10%), and of yeasts Candida albicans (11%) and Cryptococcus neoformans (8%). Less activity was detected against representatives of enterobacteria and filamentous fungi. The most productive in terms of bioactivities were cold-tolerant cosmopolitan hyphomycetes such as Penicillium, Aspergillus, Beauveria and Cladosporium. Two bioactive bis-anthraquinones (rugulosin and skyrin) were identified by LC-MS as the main products in a strain of Penicillium chrysogenum isolated from a saline lake in the Vestfold Hills. LC-MS fractionation of extracts from two diverse species of Aspergillus, that exhibited relatively potent antimicrobial activities, evidenced a chemical novelty that was further investigated. To our knowledge, this is the first report of new antibiotics produced by fungi from benthic microbial mats from Antarctic lakes. It can be concluded that these microbial assemblages represent an extremely rich source for the isolation of new strains producing novel bioactive metabolites with the potential to be developed as drugs.

Background: Numerous organisms have been identified in dental unit waterlines, or DUWLs. Decontamination of DUWLs focuses on maintaining heterotrophic, mesophilic bacteria below 200 colony-forming units per milliliter as recommended by the ADA., Methods: The authors conducted a study to test the efficacy of a continuous-use, stabilized chlorine dioxide proprietary compound to decrease the number of bacteria in DUWLs. The authors used three dental units with self-contained water systems to test the product and three similar units as controls. They aseptically collected water samples weekly according to recommended methods, plated the samples on R2A agar and incubated them for seven days., Results: The authors isolated heterotrophic, mesophilic bacteria from treatment and control units for eight weeks. In the ninth week, the predominant isolates from one of the treatment units changed in appearance to small, dark, shiny colonies that the authors tentatively identified as fungal. The authors then isolated similar colonies from the source tap water and ultrasonic and handpiece lines. They added three additional dental units from the same clinic in the sixth week of the study and isolated similar fungal colonies from them after five weeks of treatment. The authors performed DNA sequencing with an automated sequencer and identified the organism Exophiala mesophila., Conclusions: The authors did not observe fungal isolates in the control units, which suggests that continuous waterline treatment may cause proliferation of a fungus present in small amounts in source water. CLINICAL IMPLICATIONS. The findings of this study indicate the need to monitor water quality regularly when treating waterlines with continuous-use chemical cleaners.