Although endemic mycoses are a frequent health problem in Latin American countries, clinical and epidemiological data remain scarce and fragmentary. These mycoses have a significant impact on publi...

Epidemiology of endemic systemic fungal infections in Latin America

Phylogenetic analysis reveals a high level of speciation in the Paracoccidioides genus.

Paracoccidioidomycosis is a systemic fungal disease occurring in Latin America that is associated with rural environments and agricultural activities. However, the incidence and prevalence of paracoccidiodomycosis is underestimated because of the lack of compulsory notification. If paracoccidiodomycosis is not diagnosed and treated early and adequately, the endemic fungal infection could result in serious sequelae. While the Paracoccidioides brasiliensis ( P. brasiliensis ) complex has been known to be the causal agent of paracoccidiodomycosis, a new species, Paracoccidioides lutzii ( P. lutzii ), has been reported in Rondonia, where the disease has reached epidemic levels, and in the Central West and Para. Accurate diagnoses and availability of antigens that are reactive with the patients' sera remain significant challenges. Therefore, the present guidelines aims to update the first Brazilian consensus on paracoccidioidomycosis by providing evidence-based recommendations for bedside patient management. This consensus summarizes etiological, ecoepidemiological, molecular epidemiological, and immunopathological data, with emphasis on clinical, microbiological, and serological diagnosis and management of clinical forms and sequelae, as well as in patients with comorbidities and immunosuppression. The consensus also includes discussion of outpatient treatments, severe disease forms, disease prevalence among special populations and resource-poor settings, a brief review of prevention and control measures, current challenges and recommendations.

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Brazilian guidelines for the clinical management of paracoccidioidomycosis

The number of undescribed species of lichenized fungi has been estimated at roughly 10,000. Describing and cataloging these would take the existing number of taxonomists several decades; however, the support for taxonomy is in decline worldwide. In this paper we emphasize the dire need for taxonomic expertise in lichenology. We bring together 103 colleagues from institutions worldwide to describe a total of 100 new species of lichenized fungi, representing a wide taxonomic and geographic range. The newly described species are: Acarospora flavisparsa, A. janae, Aderkomyces thailandicus, Amandinea maritima, Ampliotrema cocosense, Anomomorpha lecanorina, A. tuberculata, Aspicilia mansourii, Bacidina sorediata, Badimia multiseptata, B. vezdana, Biatora epirotica, Buellia sulphurica, Bunodophoron pinnatum, Byssoloma spinulosum, Calopadia cinereopruinosa, C. editae, Caloplaca brownlieae, C. decipioides, C. digitaurea, C. magnussoniana, C. mereschkowskiana, C. yorkensis, Calvitimela uniseptata, Chapsa microspora, C. psoromica, C. rubropulveracea, C. thallotrema, Chiodecton pustuliferum, Cladonia mongkolsukii, Clypeopyrenis porinoides, Coccocarpia delicatula, Coenogonium flammeum, Cresponea ancistrosporelloides, Crocynia microphyllina, Dictyonema hernandezii, D. hirsutum, Diorygma microsporum, D. sticticum, Echinoplaca pernambucensis, E. schizidiifera, Eremithallus marusae, Everniastrum constictovexans, Fellhanera borbonica, Fibrillithecis sprucei, Fissurina astroisidiata, F. nigrolabiata, F. subcomparimuralis, Graphis caribica, G. cerradensis, G. itatiaiensis, G. marusa, Gyalideopsis chicaque, Gyrotrema papillatum, Harpidium gavilaniae, Hypogymnia amplexa, Hypotrachyna guatemalensis, H. indica, H. lueckingii, H. paracitrella, H. paraphyscioides, H. parasinuosa, Icmadophila eucalypti, Krogia microphylla, Lecanora mugambii, L. printzenii, L. xanthoplumosella, Lecidea lygommella, Lecidella greenii, Lempholemma corticola, Lepraria sekikaica, Lobariella sipmanii, Megalospora austropacifica, M. galapagoensis, Menegazzia endocrocea, Myriotrema endoflavescens, Ocellularia albobullata, O. vizcayensis, Ochrolechia insularis, Opegrapha viridipruinosa, Pannaria phyllidiata, Parmelia asiatica, Pertusaria conspersa, Phlyctis psoromica, Placopsis imshaugii, Platismatia wheeleri, Porina huainamdungensis, Ramalina hyrcana, R. stoffersii, Relicina colombiana, Rhizocarpon diploschistidina, Sticta venosa, Sagenidiopsis isidiata, Tapellaria albomarginata, Thelotrema fijiense, Tricharia nigriuncinata, Usnea galapagona, U. pallidocarpa, Verrucaria rhizicola, and Xanthomendoza rosmarieae. In addition, three new combinations are proposed: Fibrillithecis dehiscens, Lobariella botryoides, and Lobariella pallida.

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One hundred new species of lichenized fungi : a signature of undiscovered global diversity

Sporothrix schenckii, previously assumed to be the sole agent of human and animal sporotrichosis, is in fact a species complex. Recently recognized taxa include S. brasiliensis, S. globosa, S. mexicana, and S. luriei, in addition to S. schenckii sensu stricto. Over the last decades, large epidemics of sporotrichosis occurred in Brazil due to zoonotic transmission, and cats were pointed out as key susceptible hosts. In order to understand the eco-epidemiology of feline sporotrichosis and its role in human sporotrichosis a survey was conducted among symptomatic cats. Prevalence and phylogenetic relationships among feline Sporothrix species were investigated by reconstructing their phylogenetic origin using the calmodulin (CAL) and the translation elongation factor-1 alpha (EF1α) loci in strains originated from Rio de Janeiro (RJ, n = 15), Rio Grande do Sul (RS, n = 10), Parana (PR, n = 4), Sao Paulo (SP, n = 3) and Minas Gerais (MG, n = 1). Our results showed that S. brasiliensis is highly prevalent among cats (96.9%) with sporotrichosis, while S. schenckii was identified only once. The genotype of Sporothrix from cats was found identical to S. brasiliensis from human sources confirming that the disease is transmitted by cats. Sporothrix brasiliensis presented low genetic diversity compared to its sister taxon S. schenckii. No evidence of recombination in S. brasiliensis was found by split decomposition or PHI-test analysis, suggesting that S. brasiliensis is a clonal species. Strains recovered in states SP, MG and PR share the genotype of the RJ outbreak, different from the RS clone. The occurrence of separate genotypes among strains indicated that the Brazilian S. brasiliensis epidemic has at least two distinct sources. We suggest that cats represent a major host and the main source of cat and human S. brasiliensis infections in Brazil.

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Phylogenetic analysis reveals a high prevalence of Sporothrix brasiliensis in Feline sporotrichosis outbreaks

Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis, a disease confined to Latin America and of marked importance in the endemic areas due to its frequency and severity. This species is considered to be clonal according to mycological criteria and has been shown to vary in virulence. To characterize natural genetic variation and reproductive mode in this fungus, we analyzed P. brasiliensis phylogenetically in search of cryptic species and possible recombination using concordance and nondiscordance of gene genealogies with respect to phylogenies of eight regions in five nuclear loci. Our data indicate that this fungus consists of at least three distinct, previously unrecognized species: S1 (species 1 with 38 isolates), PS2 (phylogenetic species 2 with six isolates), and PS3 (phylogenetic species 3 with 21 isolates). Genealogies of four of the regions studied strongly supported the PS2 clade, composed of five Brazilian and one Venezuelan isolate. The second clade, PS3, composed solely of 21 Colombian isolates, was strongly supported by the alpha-tubulin genealogy. The remaining 38 individuals formed S1. Two of the three lineages of P. brasiliensis, S1 and PS2, are sympatric across their range, suggesting barriers to gene flow other than geographic isolation. Our study provides the first evidence for possible sexual reproduction in P. brasiliensis S1, but does not rule it out in the other two species.

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Cryptic Speciation and Recombination in the Fungus Paracoccidioides brasiliensis as Revealed by Gene Genealogies

Paracoccidioides brasiliensis is a dimorphic fungus that is the causative agent of paracoccidioidomycosis, the most important prevalent systemic mycosis in Latin America. Recently, the existence of three genetically isolated groups in P. brasiliensis was demonstrated, enabling comparative studies of molecular evolution among P. brasiliensis lineages. Thirty-two gene sequences coding for putative virulence factors were analyzed to determine whether they were under positive selection. Our maximum likelihood–based approach yielded evidence for selection in 12 genes that are involved in different cellular processes. An in-depth analysis of four of these genes showed them to be either antigenic or involved in pathogenesis. Here, we present evidence indicating that several replacement mutations in gp43 are under positive balancing selection. The other three genes (fks, cdc42 and p27) show very little variation among the P. brasiliensis lineages and appear to be under positive directional selection. Our results are consistent with the more general observations that selective constraints are variable across the genome, and that even in the genes under positive selection, only a few sites are altered. We present our results within an evolutionary framework that may be applicable for studying adaptation and pathogenesis in P. brasiliensis and other pathogenic fungi.

Jason T. Rauscher

Papers

Cryptic Speciation and Recombination in the Fungus Paracoccidioides brasiliensis as Revealed by Gene Genealogies

Evidence for positive selection in putative virulence factors within the Paracoccidioides brasiliensis species complex.

Marine isolates of Aspergillus flavus: denizens of the deep or lost at sea?