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Fungal keratitis is caused by a wide spectrum of fungal genera, including molds and yeasts. We report a 42-year-old patient with mycotic keratitis after a direct trauma by a wood fragment. The fungal isolate was identified as Roussoella neopustulans by molecular methods. The treatment with topic natamycin showed progressive improvement of the visual manifestations, and following three months of therapy, the patient regained sight. We report the first case of keratitis associated with R. neopustulans. [ABSTRACT FROM AUTHOR]

Chromoblastomycosis is a chronic severely mutilating disease caused by fungi of the order Chaetothyriales. Classically, Phialophora verrucosa has been listed among these etiologic agents. This species is known to occur in the environment and has been found to cause other infections like phaeohyphomycosis, while reported cases of chromoblastomycosis are scant. Phialophora is phylogenetically diverse, and thus retrospective confirmation of etiology is necessary. We studied ten proven cases of chromoblastomycosis from Mexico and further analyzed the population genetics and genomics of the Phialophora species to understand their pathogenicity and predilection. The clinical strains were molecularly identified as Phialophora americana (n = 4), Phialophora chinensis (n = 4), and Phialophora macrospora (n = 2). No genetic distinction between clinical and environmental strains was possible. Further analysis of strains from diverse origins are needed to address eventual differences in virulence and niche predilection between the species. [ABSTRACT FROM AUTHOR]

Chromoblastomycosis (CBM) is a neglected implantation mycosis prevalent in tropical climate zones, considered an occupational disease that affects impoverished rural populations. This retrospective study described clinical aspects of CBM in a hyperendemic area in Brazil and constructed a worldwide haplotype network of Fonsecaea spp. strains. The variables were collected from medical records using a standard report form, reporting 191 patients with CBM from Maranhão, Brazil. The mean age was 56.1 years, 168 (88%) patients were male and predominantly farmers (85.8%). The mean time of evolution of the disease until diagnosis was 9.4 years. Lower limbs (81.2%) and upper limbs (14.2%) were the main sites affected. Most patients exhibited verrucous (55%) and infiltrative plaque (48.2%). Fonsecaea spp. were identified in 136 cases and a haplotype network constructed with ITS sequences of 185 global strains revealed a total of 59 haplotypes exhibiting high haplotypic and low nucleotide diversities. No correlation was observed between the different haplotypes of Fonsecaea species and dermatological patterns, severity of disease or geographic distribution inside Maranhão. Data from this area contributed to better understanding the epidemiology of CBM. For the first time, a robust haplotype network with Fonsecaea strains reveals an evolutionary history with a recent population expansion. [ABSTRACT FROM AUTHOR]

The fungal genus Fonsecaea contains etiological agents of human chromoblastomycosis, a (sub)tropical, (sub)cutaneous implantation disease caused by plant contact. The invasive potential differs significantly between species. Infections by Fonsecaea monophora are believed to originate from the environment and the species has been reported as one of the main causative agents of the disease, but also of cases of primary brain infection. The epidemiology of the disease has not been fully elucidated and questions related to its infection route and virulence are still to be clarified. The environmental species Fonsecaea erecta was isolated from organic material and living plants in endemic areas for chromoblastomycosis in Brazil. The present paper describes Agrobacterium tumefaciens-mediated transformation (AMT) of the environmental species F. erecta and the pathogenic species F. monophora. We propose the use of Agrobacterium transformation for future gene function studies related to Fonsecaea virulence and pathogenicity. We evaluated the co-cultivation ratios 1:1, 10:1 and 100:1 (Agrobacterium:conidia) at 28 °C during 72 h. pAD1625 and pCAMDsRed plasmids were inserted into both species. Confirmation of transformation was realized by hph gene amplification and Southern blot determined the amount of foreign DNA integrated into the genome. In order to evaluate a potential link between environmental and clinical strains, we obtained red fluorescent transformants after pCAMDsRed insertion. We observed by confocal fluorescence microscopy that both F. monophora and F. erecta were able to colonize the palm Bactris gasipaes, penetrating the epidermis. These results contribute to understanding the ability of Fonsecaea species to adapt to different environmental and host conditions. [ABSTRACT FROM AUTHOR]