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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.

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.

SUMMARY Chromoblastomycosis (CBM), also known as chromomycosis, is one of the most prevalent implantation fungal infections, being the most common of the gamut of mycoses caused by melanized or brown-pigmented fungi. CBM is mainly a tropical or subtropical disease that may affect individuals with certain risk factors around the world. The following characteristics are associated with this disease: (i) traumatic inoculation by implantation from an environmental source, leading to an initial cutaneous lesion at the inoculation site; (ii) chronic and progressive cutaneous and subcutaneous tissular involvement associated with fibrotic and granulomatous reactions associated with microabscesses and often with tissue proliferation; (iii) a nonprotective T helper type 2 (Th2) immune response with ineffective humoral involvement; and (iv) the presence of muriform (sclerotic) cells embedded in the affected tissue. CBM lesions are clinically polymorphic and are commonly misdiagnosed as various other infectious and noninfectious diseases. In its more severe clinical forms, CBM may cause an incapacity for labor due to fibrotic sequelae and also due to a series of clinical complications, and if not recognized at an early stage, this disease can be refractory to antifungal therapy.

Species of Scedosporium and Lomentospora are considered as emerging opportunists, affecting immunosuppressed and otherwise debilitated patients, although classically they are known from causing trauma-associated infections in healthy individuals. Clinical manifestations range from local infection to pulmonary colonization and severe invasive disease, in which mortality rates may be over 80%. These unacceptably high rates are due to the clinical status of patients, diagnostic difficulties, and to intrinsic antifungal resistance of these fungi. In consequence, several consortia have been founded to increase research efforts on these orphan fungi. The current review presents recent findings and summarizes the most relevant points, including the Scedosporium/Lomentospora taxonomy, environmental distribution, epidemiology, pathology, virulence factors, immunology, diagnostic methods, and therapeutic strategies.

The chemical composition of the Bannock basin has been studied in some detail 1,2 . We recently showed that unusual microbial populations, including a new division of Archaea (MSBL1) 3 , inhabit the NaCl-rich hypersaline brine. High salinities tend to reduce biodiversity 4 , but when brines come into contact with fresher water the natural haloclines formed frequently contain gradients of other chemicals, including permutations of electron donors and acceptors, that may enhance microbial diversity, activity and biogeochemical cycling 5,6 . Here we report a 2.5-mthick chemocline with a steep NaCl gradient at 3.3 km within the water column betweeen Bannock anoxic hypersaline brine 7 and overlying sea water. The chemocline supports some of the most biomass-rich and active microbial communities in the deep sea, dominated by Bacteria rather than Archaea, and including four major new divisions of Bacteria. Significantly higher metabolic activities were measured in the chemocline than in the overlying sea water and underlying brine; functional analyses indicate that a range of biological processes is likely to occur in the chemocline. Many prokaryotic taxa, including the phylogenetically new groups, were confined to defined salinities, and collectively formed a diverse, sharply stratified, deep-sea ecosystem with sufficient biomass to potentially contribute to organic geological deposits.High-precision sampling was conducted during cruises of the research vessel Urania equipped with the Modus-Scipack system (http://www.geo.unimib.it/BioDeep/Project.html; Fig. 1a). The vehicle Modus, connected by cable to the research vessel, held a second instrument, the Scipack, with a 10-m data transmission cable. The Scipack, consisting of a Rosette sampler equipped with a CTD (conductivity-temperature-depth probe) and a series of Niskin bottles, was connected to the Modus through the Sciskid, a module equipped with a pressure sensor for recording the pressure at which the Niskin bottles were closed (Fig. 1c). A camera on the Modus could provide an image of the Scipack entering the brine lake (Fig. 1b, and Supplementary Fig. S1). Immediately after sampling, the Modus-Scipack was raised, the Niskin bottles were retrieved and their contents were carefully fractionated on board ship by slowly recovering 0.5-litre, 1-litre or 2-litre fractions from the bottom tap. These were then immediately analysed for salinity (Fig. 1d). The reconstructed interface salinity profile was strongly positively correlated (r ¼ 0.98, P , 0.001) with the CTD conductivity profile recorded in independent non-sampling casts (Fig. 2d), indicating that little or no mixing had occurred.The interface halocline was about 2.5 m deep, in agreement with previous estimates that employed alternative sampling strategies 1 . Although biomass values fluctuated along the halocline, there were significantly greater numbers of microbial cells in the interface (about 10 6 cells ml 21 ) than in either the deep sea water or the underlying hypersaline brine, both of which had about...

Sporothrix schenckii sensu lato is a complex of thermally dimorphic species whose natural habitats are soil and plant materials. However, the traumatic implantation of the species into human skin is traditionally thought to be the route leading to the fungal disease sporotrichosis. The complex contains Sporotrhix mexicana, S. globosa, S. brasiliensis, S. luriei, in addition to S. schenckii sensu stricto. In this study we evaluated the differences among these species relative to their frequency in the environment and in human hosts, as well as discuss their remarkable diverse pathogenicity. Today, S. brasiliensis is epidemic in and geographically restricted to Brazil. In contrast, S. mexicana and S. globosa have rarely been reported over the decades. We discovered that the species have been present in collections from clinical cases since 1955 and were able to re-identify six isolates originally classified as S. schenckii as Sporothrix mexicana (three isolates) and Sporothrix globosa (three isolates). Despite their long presence as potential human pathogens they have not shown any increase in frequency as etiologic agents of human infections.

Summary Recent discoveries of novel systemic fungal pathogens with thermally dimorphic yeast-like phases have challenged the current taxonomy of the Ajellomycetaceae, a family currently comprising the genera Blastomyces, Emmonsia, Emmonsiellopsis, Helicocarpus, Histoplasma, Lacazia and Paracoccidioides. Our morphological, phylogenetic and phylogenomic analyses demonstrated species relationships and their specific phenotypes, clarified generic boundaries and provided the first annotated genome assemblies to support the description of two new species. A new genus, Emergomyces, accommodates Emmonsia pasteuriana as type species, and the new species Emergomyces africanus, the etiological agent of case series of disseminated infections in South Africa. Both species produce small yeast cells that bud at a narrow base at 37 °C and lack adiaspores classically associated with the genus Emmonsia. Another novel dimorphic pathogen, producing broad-based budding cells at 37 °C and occurring outside North America, proved to belong to the genus Blastomyces, and is described as Blastomyces percursus.