Experimental infections with Paracoccidioides brasiliensis obtained from armadillos: comparison to clinical isolates

Paracoccidioides brasiliensis causes paracoccidioidomycosis (PCM) that is one of the most prevalent systemic human mycoses in Latin America. Armadillos show a high incidence of PCM infection and could, therefore, be a natural reservoir for this fungus. In this study were compared the virulence profiles of isolates obtained from nine-banded armadillos (Dasypus novemcinctus) (PbT1 and PbT4) and isolates from PCM patients (Pb265 and Bt83). Pathogenicity was evaluated by fungal load and analysis of colony morphology. Immunity against the fungus was tested by delayed type hypersensitivity test (DTH) and antibody quantification by ELISA. The higher virulence of PbT1 and PbT4 was suggested by higher fungal load in spleen and lungs. Armadillo isolates and Bt83 presented a cotton-like surface contrasting with the cerebriform appearance of Pb265. All isolates induced cellular and humoral immune responses in infected BALB/c mice. DTH reactions were similarly induced by the four isolates, however, a great variability was observed in specific antibody levels, being the highest ones induced by Bt83 and PbT4. The present work confirms that armadillos harbor P. brasiliensis, whose multiplication and induced immunity in experimentally infected mice are heterogeneous, resembling the behavior of isolates from human PCM. This study reinforces the possibility that armadillos play an important role in the biological cycle of this pathogen

Paracoccidioides species complex : ecology, phylogeny, sexual reproduction, and virulence

Paracoccidioidomycosis (PCM) is a deep systemic mycosis caused by human fungal pathogens of the Paracoccidioides genus. The disease is geographically restricted to subtropical areas of Latin America (from south of Mexico to north of Argentina) with a high prevalence in Brazil, Colombia, Venezuela, and Argentina [1]. The annual incidence rate in Brazil is 10–30 infections per million inhabitants, and the mean mortality rate is 1.4 per million inhabitants per year, making this disease the highest cause of mortality among systemic mycoses [2]. PCM is endemic in rural populations and mainly affects individuals engaged in agricultural activities, who inhale aerosols containing fungal material during manipulation of the soil. Molecular evolutionary studies place the genus Paracoccidioides in the thermodimorphic fungal pathogen clade related to the family Ajellomycetaceae (Ascomycetes), which includes the Blastomyces, Histoplasma, and Emmonsia genera, and with which it shares a common ancestor, Lacazia loboi. PCM can be caused by two species Paracoccidioides brasiliensis and P. lutzii [3]. P. brasiliensis has been considered a single species since its discovery, although several studies including molecular and morphological data support the split of P. brasiliensis into two species [3,4]. P. lutzii is composed of a single monophyletic and recombining population so far found in central, southwest, and north Brazil and Ecuador [3–5]. On the other hand, P. brasiliensis contains a complex of at least four different cryptic species (S1, PS2, PS3 and PS4; Figure 1A [6]). P. brasiliensis S1 represents a monophyletic and recombining population widely distributed in South America and has been associated with the majority of cases of PCM detected up until the present time. Strains belonging to P. brasiliensis S1 have previously been recovered from armadillos, soil, and penguin feces [6]. P. brasiliensis PS2 is a paraphyletic and recombining population identified so far only in Brazil and Venezuela [6]. P. brasiliensis PS3 is comprised of a monophyletic and clonal population that has been recovered in humans and armadillos in endemic regions of Colombia [6]. P. brasiliensis PS4 was recently identified and is composed of a monophyletic population of clinical isolates from Venezuela [5,7]. Besides the typical bicorn cocked hat– and barrel-shaped conidia produced by both species, P. lutzii frequently produces elongated rod-shaped conidia, a characteristic feature that may be used for species identification [3]. Because of the difficulties of conidia production in the laboratory and slight morphological differences among species, molecular identification of Paracoccidioides species has become the most common tool of choice. Several molecular markers have already been applied in population studies of the Pararacoccidioides genus, and for multilocus sequencing typing, gp43, arf, b-tub, and hsp70 loci are the best choices for species delineation [4,6]

Sistemas de seguro nacional de saúde e respostas às legitimas expectativas dos cidadãos

Os sistemas de saúde assumem a responsabilidade não só de melhorar a saúde das populações mas também de as proteger do custo da doença e de as tratar com dignidade. Tendo por base as três dimensões que definem os sistemas de saúde (regulação, financiamento e prestação), e que cada dimensão pode ser dominada por três tipos de atores (estado, social e privado), no âmbito deste trabalho é nosso propósito estudar os sistemas de saúde de tipo Seguro Nacional de Saúde (nomeadamente dos países como o Canadá, a Austrália, a Nova Zelândia e a Irlanda), na perspetiva das respostas às legitimas expectativas dos cidadãos. Assim, iremos proceder a uma revisão da literatura para chegarmos aos objetivos específicos: (i) descrever sucintamente os sistemas de saúde baseados no seguro nacional de saúde, onde se podem incluir a Austrália, Canadá, Irlanda e Nova Zelândia; (ii) caracterizar o conceito de responsiveness; (iii) identificar a presença da responsiveness nestes sistemas. A forma como os sistemas de saúde interagem com as pessoas é determinante para o seu bem estar. Avaliar o desempenho dos sistemas de saúde não se limita à avaliação dos resultados em saúde mas também no respeito e integração dos princípios éticos e dos direitos humanos

Species distribution and susceptibility profile of Candida species in a Brazilian public tertiary hospital

<p>Abstract</p> <p>Background</p> <p>Species identification and antifungal susceptibility tests were carried out on 212 <it>Candida </it>isolates obtained from bloodstream infections, urinary tract infections and dialysis-associated peritonitis, from cases attended at a Brazilian public tertiary hospital from January 1998 to January 2005.</p> <p>Findings</p> <p><it>Candida albicans </it>represented 33% of the isolates, <it>Candida parapsilosis </it>31.1%, <it>Candida tropicalis </it>17.9%,<it>Candida glabrata </it>11.8%, and others species 6.2%. In blood culture, <it>C. parapsilosis </it>was the most frequently encountered species (48%). The resistance levels to the antifungal azoles were relatively low for the several species, except for <it>C. tropicalis </it>and <it>C. glabrata</it>. Amphotericin B resistance was observed in 1 isolate of <it>C. parapsilosis</it>.</p> <p>Conclusions</p> <p>The species distribution and antifungal susceptibility herein observed presented several epidemiological features common to other tertiary hospitals in Latin American countries. It also exhibited some peculiarity, such as a very high frequency of <it>C. parapsilosis </it>both in bloodstream infections and dialysis-associated peritonitis. <it>C. albicans </it>also occurred in an important number of case infections, in all evaluated clinical sources. <it>C. glabrata </it>presented a high proportion of resistant isolates. The data emphasize the necessity to carry out the correct species identification accompanied by the susceptibility tests in all tertiary hospitals.</p

Importance of xenarthrans in the eco-epidemiology of Paracoccidioides brasiliensis

Abstract\ud Background\ud Several pathogens that cause important zoonotic diseases have been frequently associated with armadillos and other xenarthrans. This mammal group typically has evolved on the South American continent and many of its extant species are seriously threatened with extinction. Natural infection of armadillos with Paracoccidioides brasiliensis in hyperendemic areas has provided a valuable opportunity for understanding the role of this mammal in the eco-epidemiology of Paracoccidioidomycosis (PCM), one of the most important systemic mycoses in Latin America.\ud \ud Findings\ud This study aimed to detect P. brasiliensis in different xenarthran species (Dasypus novemcinctus, Cabassous spp., Euphractus sexcinctus, Tamandua tetradactyla and Myrmecophaga tridactyla), by molecular and mycological approaches, in samples obtained by one of the following strategies: i) from road-killed animals (n = 6); ii) from naturally dead animals (n = 8); iii) from animals that died in captivity (n = 9); and iv) from living animals captured from the wild (n = 2). Specific P. brasiliensis DNA was detected in several organs among 7/20 nine-banded armadillos (D. novemcinctus) and in 2/2 anteaters (M. tridactyla). The fungus was also cultured in tissue samples from one of two armadillos captured from the wild.\ud \ud Conclusion\ud Members of the Xenarthra Order, especially armadillos, have some characteristics, including a weak cellular immune response and low body temperature, which make them suitable models for studying host-pathogen interaction. P. brasiliensis infection in wild animals, from PCM endemic areas, may be more common than initially postulated and reinforces the use of these animals as sentinels for the pathogen in the environment.This work was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP-n° 05/56771-9, 06/03597-4). We also thank the Departamento de Estradas de Rodagem do Estado de São Paulo (DER), as well as Prof. Dr. Reinaldo José da Silva and Juliana Griese for information about the road-killed animals.This work was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESPn° 05/567719, 06/035974). We also thank the Departamento de Estradas de Rodagem do Estado de São Paulo (DER), as well as Prof. Dr. Reinaldo José da Silva and Juliana Griese for information about the roadkilled animals

Paracoccidioidomycosis due to Paracoccidioides lutzii complicated with adrenal injury and pulmonary arterial hypertension

Paracoccidioidomycosis caused by Paracoccidioides lutzii is endemic in the Midwest of Brazil and its clinical spectrum is still little known due to the recent identification of this fungal species. A patient resident in Southeast Brazil, but who had lived for many years in the Midwest region, presented with skin injuries, chronic cough and bilateral adrenal involvement. Paracoccidioides spp. was isolated in culture from a skin lesion biopsy. This isolate was later identified as P. lutzii using gene sequencing. A favorable initial response to treatment with itraconazole was observed, but a few weeks later, the patient developed respiratory failure and worsening of lung lesions. Evaluation by computed tomography and echocardiography were suggestive of pulmonary arterial hypertension, and a bronchoscopic biopsy showed peribronchial remodeling. The patient completed the antifungal treatment but maintained the respiratory dysfunction. The reported case shows that P. lutzii can be isolated from patients in a geographic area far from the place of infection acquisition and that, as P. brasiliensis , it can cause adrenal injury and cardio-respiratory complications as a consequence of excessive necrosis and fibrosis

Ecological study of Paracoccidioides brasiliensis in soil: growth ability, conidia production and molecular detection

<p>Abstract</p> <p>Background</p> <p><it>Paracoccidioides brasiliensis </it>ecology is not completely understood, although several pieces of evidence point to the soil as its most probable habitat. The present study aimed to investigate the fungal growth, conidia production and molecular pathogen detection in different soil conditions.</p> <p>Methods</p> <p>Soils samples of clayey, sandy and medium textures were collected from ground surface and the interior of armadillo burrows in a hyperendemic area of Paracoccidioidomycosis. <it>P</it>. <it>brasiliensis </it>was inoculated in soil with controlled humidity and in culture medium containing soil extracts. The molecular detection was carried out by Nested PCR, using panfungal and species specific primers from the ITS-5.8S rDNA region.</p> <p>Results</p> <p>The soil texture does not affect fungus development and the growth is more abundant on/in soil saturated with water. Some soil samples inhibited the development of <it>P. brasiliensis</it>, especially those that contain high values of Exchangeable Aluminum (H+Al) in their composition. Some isolates produced a large number of conidia, mainly in soil-extract agar medium. The molecular detection was positive only in samples collected from armadillo burrows, both in sandy and clayey soil.</p> <p>Conclusion</p> <p><it>P. brasiliensis </it>may grow and produce the infectious conidia in sandy and clayey soil, containing high water content, mainly in wild animal burrows, but without high values of H+Al.</p

Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Differentiation of the Dimorphic Fungal Species Paracoccidioides brasiliensis and Paracoccidioides lutzii

Isolates of Paracoccidioides brasiliensis and Paracoccidioides lutzii, previously characterized by molecular techniques, were identified for the first time by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). All isolates were correctly identified, with log score values of >2.0. Thus, MALDI-TOF MS is a new tool for differentiating species of the genus Paracoccidioides.Univ São Paulo, Fac Med, Hosp Clin, Cent Lab Div LIM03, São Paulo, BrazilUniv São Paulo, Inst Med Trop, Hosp Clin FMUSP, Lab Med Mycol LIM53, São Paulo, BrazilUniv São Paulo, Dept Biophys, Escola Paulista Med, São Paulo, BrazilUniv Estadual Paulista, Dept Microbiol & Immunol, Inst Biociencias Botucatu, Botucatu, SP, BrazilUniv São Paulo, Dept Biophys, Escola Paulista Med, São Paulo, BrazilWeb of Scienc