Onychomycosis is a fungal infection of the nails with broad aetiological scope, and it represents 18-40% of all onychopathies and 39% of all superficial mycotic infections. From July 1996 to December 1999, samples of nails were collected from 588 patients with presumptive diagnosis of onychomycosis at the Dermatology and Mycology Divisions EPM\UNIFESP, Brazil, and the diagnosis was confirmed in 247 of these cases. The most common pathogens isolated in this study were yeasts in 52% of positive cultures (Candida albicans 18.3%, Candida parapsilosis 13.8%, other species of Candida 15.4% and other yeasts 4.6%), followed by dermatophytes in 40.6% of positive cultures (the most commonly isolated organisms were Trichophyton rubrum in 33.2%, followed by Trichophyton mentagrophytes in 6.3% and others 1.2%). Non-dermatophyte moulds were isolated in 7.4% of positive cultures (Fusarium spp. 4.5%, Nattrassia mangiferae 2.3% and Aspergillus spp. 0.6%). Distal and lateral subungual onychomycosis (DLSO) was the commonest clinical pattern 44.6% followed by free edge onycholysis (FEO) 38.8% and others. In conclusion, this study demonstrated that T. rubrum is the main agent causing onychomycosis in toenails, and species of genus Candida were the main agents isolated in fingernail onychomycosis in our region.

BackgroundWe conducted a prospective study to investigate the presence of microfungal contamination in the water supply system of the Oncology Paediatric Institute, São Paulo – Brazil after the occurrence of one invasive Fusarium solani infection in a patient after Haematopoietic Stem Cell Transplantation (HSCT). During a twelve-month period, we investigated the water supply system of the HSCT unit by monitoring a total of fourteen different collection sites.MethodsOne litre of water was collected in each location, filtered through a 0.45 μm membrane and cultured on SDA to detect the presence of filamentous fungi. Physicochemical analyses of samples were performed to evaluate the temperature, turbidity, pH, and the concentration of free residual chlorine.ResultsOver the 12 months of the study, 164 samples were collected from the water supply system of the HSCT unit, and 139 of the samples tested positive for filamentous fungi (84.8%), generating a total of 2,362 colonies. Cladosporium spp., Penicillium spp., Purpureocillium spp. and Aspergillus spp. were ranked as the most commonly found genera of mould in the collected samples. Of note, Fusarium solani complex isolates were obtained from 14 out of the 106 samples that were collected from tap water (mean of 20 CFU/L). There was a positive correlation between the total number of fungal CFU obtained in all cultures and both water turbidity and temperature parameters. Our findings emphasise the need for the establishment of strict measures to limit the exposure of high-risk patients to waterborne fungal propagules.ConclusionsWe were able to isolate a wide variety of filamentous fungi from the water of the HSCT unit where several immunocompromised patients are assisted.

During a survey on the incidence of Aspergillus in clinical environments, we found some interesting isolates that were morphologically similar to Aspergillus parasiticus, but differed in the color of the colonies and in the pattern of their conidial ornamentation. In the present study, those isolates were characterized using a polyphasic approach. A phylogenetic analysis was carried out, based on partial fragments of the acetamidase (amdS) and O-methyltransferase (omtS) genes and the internal transcribed spacer (ITS) region of rDNA. This information was combined with a detailed morphological and physiological study that included aflatoxin production and assimilation profiles of different carbon and nitrogen sources. The phenotypic and genotypic results support the proposal of a new species, Aspergillus novoparasiticus, phylogenetically placed in a distinct sister clade to that of A. parasiticus. The former has lobate-reticulate conidia and does not produce aspergillic acid on AFPA or organic acids on CREA, while A. parasiticus has echinulate conidia and produces aspergillic and organic acids. In addition, this new species, as well as A. parasiticus, produces aflatoxins B1, B2, G1 and G2.

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