- Record: found
- Abstract: found
- Article: found
Sporotrichosis: An Overview and Therapeutic Options
review-article
Publication date (Electronic):
29 December 2014
Journal:
Dermatology Research and Practice
Publisher:
Hindawi Publishing Corporation
Read this article at
There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Sporotrichosis is a chronic granulomatous mycotic infection caused by Sporothrix schenckii, a common saprophyte of soil, decaying wood, hay, and sphagnum moss, that is endemic in tropical/subtropical areas. The recent phylogenetic studies have delineated the geographic distribution of multiple distinct Sporothrix species causing sporotrichosis. It characteristically involves the skin and subcutaneous tissue following traumatic inoculation of the pathogen. After a variable incubation period, progressively enlarging papulo-nodule at the inoculation site develops that may ulcerate (fixed cutaneous sporotrichosis) or multiple nodules appear proximally along lymphatics (lymphocutaneous sporotrichosis). Osteoarticular sporotrichosis or primary pulmonary sporotrichosis are rare and occur from direct inoculation or inhalation of conidia, respectively. Disseminated cutaneous sporotrichosis or involvement of multiple visceral organs, particularly the central nervous system, occurs most commonly in persons with immunosuppression. Saturated solution of potassium iodide remains a first line treatment choice for uncomplicated cutaneous sporotrichosis in resource poor countries but itraconazole is currently used/recommended for the treatment of all forms of sporotrichosis. Terbinafine has been observed to be effective in the treatment of cutaneous sporotrichosis. Amphotericin B is used initially for the treatment of severe, systemic disease, during pregnancy and in immunosuppressed patients until recovery, then followed by itraconazole for the rest of the therapy.
Related collections
Most cited references122
- Record: found
- Abstract: found
- Article: not found
Sporothrix brasiliensis, S. globosa, and S. mexicana, three new Sporothrix species of clinical interest.
Josepa Gené, Josep Cano, Rita Marimon … (2007)
Sporothrix schenckii is the species responsible for sporotrichosis, a fungal infection caused by the traumatic implantation of this dimorphic fungus. Recent molecular studies have demonstrated that this species constitutes a complex of numerous phylogenetic species. Since the delineation of such species could be of extreme importance from a clinical point of view, we have studied a total of 127 isolates, most of which were received as S. schenckii, including the available type strains of species currently considered synonyms, and also some close morphological species. We have phenotypically characterized all these isolates using different culture media, growth rates at different temperatures, and numerous nutritional tests and compared their calmodulin gene sequences. The molecular analysis revealed that Sporothrix albicans, S. inflata, and S. schenckii var. luriei are species that are clearly different from S. schenckii. The combination of these phenetic and genetic approaches allowed us to propose the new species Sporothrix brasiliensis, S. globosa, and S. mexicana. The key phenotypic features for recognizing these species are the morphology of the sessile pigmented conidia, growth at 30, 35, and 37 degrees C, and the assimilation of sucrose, raffinose, and ribitol.
- Record: found
- Abstract: found
- Article: not found
Clinical practice guidelines for the management of sporotrichosis: 2007 update by the Infectious Diseases Society of America.
Jason W. Chapman, P Pappas, Robert C. Kauffman … (2007)
Guidelines for the management of patients with sporotrichosis were prepared by an Expert Panel of the Infectious Diseases Society of America and replace the guidelines published in 2000. The guidelines are intended for use by internists, pediatricians, family practitioners, and dermatologists. They include evidence-based recommendations for the management of patients with lymphocutaneous, cutaneous, pulmonary, osteoarticular, meningeal, and disseminated sporotrichosis. Recommendations are also provided for the treatment of sporotrichosis in pregnant women and in children.
- Record: found
- Abstract: found
- Article: found
Phylogenetic Analysis Reveals a High Prevalence of Sporothrix brasiliensis in Feline Sporotrichosis Outbreaks
Introduction Mycotic diseases, particularly those caused by dimorphic fungi such as Sporothrix, can be considered as an emerging threat to various species of animals. Upon introduction of propagules into the mammalian host, the fungus undergoes a thermodimorphic transition to a yeast-like phase, leading to infections varying between fixed localized cutaneous lesions to severe, disseminated sporotrichosis. The first connection between Sporothrix and animals was made by Lutz and Splendore [1]. Since then sporotrichosis has been reported in dogs, cats, horses, cows, camels, dolphins, goats, mules, birds, pigs, rats, and armadillos, as well as in humans. However, the cat is the animal species most affected by this mycosis [2]. Over the last two decades, Brazil has experienced its largest epidemic of sporotrichosis due to zoonotic transmission, whereby cats were pointed out as key susceptible host. The zoonotic potential of infected cats has been demonstrated by the isolation of S. schenckii s.l. from feline skin lesions, nasal, oral cavities, and claw fragments [3], [4]. In contrast to the classical route of infection by Sporothrix, where soil and plant material loaded with saprophytic hyphae of the pathogen were the source of contamination [5], transmission of Sporothrix spp. by cats to other cats and to humans via direct inoculation of yeast cells represents an alternative and a successful type of dispersal of the disease. The yeast form is more virulent than the mycelial form [6], [7]. Transmission of yeast cells may enhance the appearance of more severe forms of the disease. Until recently, S. schenckii was considered to be the only species causing sporotrichosis. The infection has a worldwide distribution, mainly in tropical and subtropical countries [8]–[10]. The most common clinical manifestations in humans are the lymphocutaneous and fixed forms, but other clinical types, such as a disseminated form, may also occur [11], [12], partly depending on the immune status of the host. Multilocus sequencing combined with morphological and physiological data support the separation of at least four distinct Sporothrix species within the S. schenckii complex, uniting the species with high pathogenic potential to mammals. The original taxon S. schenckii (Clades IIa and IIb) and the novel species S. brasiliensis (Clade I), S. globosa (Clade III), and S. luriei (Clade VI) todays are referred to as the S. schenckii complex [13], while the mildly pathogenic species S. mexicana (Clade IV) takes a remote position near the environmental species S. pallida [11], [14]–[19]. The Sporothrix species differ in their pathogenic potential for mammals [20], [21], their geographical distribution [11], [13], [15], [17], and in their sensitivity to antifungal therapy [22]. All species have been reported from Brazil [11]. Endemic areas of sporotrichosis in Brazil are characterized by poor sanitation, substandard housing and little or no access to health services – a challenge to control and eradication of the disease. The oldest outbreaks of sporotrichosis among humans and cats have been reported in the states of Rio de Janeiro [3], [23], [24] and Rio Grande do Sul [25], [26]. Delayed diagnosis and treatment in cats may lead to a rapid spread of the disease through the community members. The increase in the number of cases in cats is followed by higher numbers of human cases, which constitutes a serious public health problem. Despite the increasing frequency and severity of cases, the eco-epidemiology of feline sporotrichosis in Brazil is still unknown. The aim of the present study was to determine the distribution and prevalence of Sporothrix species among naturally infected felines using phenotypic and molecular phylogenetic approaches. Methods Isolates and culture conditions Thirty three (33) Sporothrix isolates from Rio de Janeiro, RJ (n = 15); Rio Grande do Sul, RS (n = 10); Paraná, PR (n = 4); São Paulo, SP (n = 3) and Minas Gerais, MG (n = 1) were obtained from lesions of cats and dogs with sporotrichosis (skin or mucosa lesions) (Fig. 1). Fungal cells were recovered directly from lesions and cultured on Mycosel agar (Difco Laboratories, Detroit, Mich.). Suspected colonies were subcultured on potato dextrose agar (Difco Laboratories, Detroit, Mich.) at room temperature. Isolates were identified phenotypically as S. schenckii s.l. As a control, human clinical isolates (n = 66) inside and outside the Brazilian feline outbreaks areas were included in the study (Table 1). 10.1371/journal.pntd.0002281.g001 Figure 1 South America map showing sampling localities in Brazil and total number of animals (n = 33) and humans Sporothrix spp. (n = 49) isolates evaluated in Rio de Janeiro, Minas Gerais, São Paulo, Paraná and Rio Grande do Sul. = 17) outside the gray area and used as control are not shown in the picture. 10.1371/journal.pntd.0002281.t001 Table 1 Strains, species, origin, and GenBank accession numbers of Sporothrix spp. isolates used in this study. GenBank Isolate code CBS code Species Source Geographic origin CAL EF1α Reference1 Ss05 CBS 132985 Sporothrix brasiliensis Feline sporotrichosis Belo Horizonte, MG, Brazil KC693830 KC576544 This study Ss53 CBS 132989 Sporothrix brasiliensis Feline sporotrichosis Rio Grande, RS, Brazil KC693846 KC576568 This study Ss54 CBS 132990 Sporothrix brasiliensis Feline sporotrichosis Rio Grande, RS, Brazil JQ041903 KC576569 This study Ss152 CBS 132995 Sporothrix brasiliensis Feline sporotrichosis Pelotas, RS, Brazil KC693865 KC576596 This study Ss153 CBS 132996 Sporothrix brasiliensis Feline sporotrichosis Pelotas, RS, Brazil KC693866 KC576597 This study Ss154 - Sporothrix brasiliensis Feline sporotrichosis Pelotas, RS, Brazil KC693867 KC576598 This study Ss155 - Sporothrix brasiliensis Feline sporotrichosis Pelotas, RS, Brazil KC693868 KC576599 This study Ss156 CBS 132997 Sporothrix brasiliensis Feline sporotrichosis Pelotas, RS, Brazil KC693869 KC576600 This study Ss157 CBS 132998 Sporothrix brasiliensis Feline sporotrichosis Pelotas, RS, Brazil KC693870 KC576601 This study Ss171 CBS 132999 Sporothrix brasiliensis Feline sporotrichosis Londrina, PR, Brazil KC693871 KC576602 This study Ss172 CBS 133000 Sporothrix brasiliensis Feline sporotrichosis Londrina, PR, Brazil KC693872 KC576603 This study Ss173 CBS 133001 Sporothrix brasiliensis Feline sporotrichosis Londrina, PR, Brazil KC693873 KC576604 This study Ss174 CBS 133002 Sporothrix brasiliensis Feline sporotrichosis Londrina, PR, Brazil KC693874 KC576605 This study Ss226 CBS 133003 Sporothrix brasiliensis Feline sporotrichosis São Paulo, SP, Brazil KC693875 KC576616 This study Ss245 CBS 133005 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693878 KC576619 This study Ss246 - Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693879 KC576620 This study Ss247 CBS 133006 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693880 KC576621 This study Ss248 CBS 133007 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693881 KC576622 This study Ss249 CBS 133008 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693882 KC576623 This study Ss250 CBS 133009 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693883 KC576624 This study Ss251 CBS 133010 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693884 KC576625 This study Ss252 CBS 133011 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693885 KC576626 This study Ss253 CBS 133012 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693886 KC576627 This study Ss254 CBS 133013 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693887 KC576628 This study Ss255 CBS 133014 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693888 KC576629 This study Ss256 CBS 133015 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693889 KC576630 This study Ss257 CBS 133016 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693890 KC576631 This study Ss258 CBS 133017 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693891 KC576632 This study Ss259 CBS 133018 Sporothrix brasiliensis Feline sporotrichosis Rio de Janeiro, RJ, Brazil KC693892 KC576633 This study Ss260 CBS 133019 Sporothrix brasiliensis Feline sporotrichosis Pelotas, RS, Brazil KC693893 KC576634 This study Ss151 CBS 132994 Sporothrix brasiliensis Canine sporotrichosis Pelotas, RS, Brazil KC693864 KC576595 This study Ss227 CBS 133004 Sporothrix brasiliensis Canine sporotrichosis São Paulo, SP, Brazil KC693876 KC576617 This study Ss07 CBS 132986 Sporothrix brasiliensis Human sporotrichosis Belo Horizonte, MG, Brazil KC693831 KC576546 This study Ss08 - Sporothrix brasiliensis Human sporotrichosis Belo Horizonte, MG, Brazil KC693832 KC576547 This study Ss09 - Sporothrix brasiliensis Human sporotrichosis Belo Horizonte, MG, Brazil KC693833 KC576548 This study Ss10 CBS 132987 Sporothrix brasiliensis Human sporotrichosis Belo Horizonte, MG, Brazil KC693834 KC576549 This study Ss12 - Sporothrix brasiliensis Human sporotrichosis Belo Horizonte, MG, Brazil KC693835 KC576550 This study Ss25 CBS 132988 Sporothrix brasiliensis Human sporotrichosis Curitiba, PR, Brazil KC693840 KC576556 This study Ss27 - Sporothrix brasiliensis Human sporotrichosis Curitiba, PR, Brazil JX077111 KC576558 [11] Ss38 - Sporothrix brasiliensis Human sporotrichosis Curitiba, PR, Brazil KC693844 KC576563 This study Ss52 - Sporothrix brasiliensis Human sporotrichosis São Paulo, SP, Brazil KC693845 KC576567 This study Ss55 - Sporothrix brasiliensis Human sporotrichosis Rio Grande, RS, Brazil KC693847 KC576570 This study Ss56 - Sporothrix brasiliensis Human sporotrichosis Rio Grande, RS, Brazil KC693848 KC576571 This study Ss62 CBS 132991 Sporothrix brasiliensis Human sporotrichosis Vila Velha, ES, Brazil JX077113 KC576572 [11] Ss69 - Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693849 KC576575 This study Ss70 - Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693850 KC576576 This study Ss71 - Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693851 KC576577 This study Ss72 - Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693852 KC576578 This study Ss79 - Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693856 KC576582 This study Ss82 CBS 132992 Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693857 KC576584 This study Ss87 CBS 132993 Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693858 KC576585 This study Ss125 - Sporothrix brasiliensis Human sporotrichosis Campinas, SP, Brazil JX077116 KC576588 [11] Ss128 - Sporothrix brasiliensis Human sporotrichosis Campinas, SP, Brazil KC693861 KC576589 This study Ss149 - Sporothrix brasiliensis Human sporotrichosis Pelotas, RS, Brazil KC693862 KC576593 This study Ss150 - Sporothrix brasiliensis Human sporotrichosis Pelotas, RS, Brazil KC693863 KC576594 This study CBS 120339T CBS 120339T Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil AM116899 KC576606 [19] IPEC 16919 - Sporothrix brasiliensis Human sporotrichosis Rio de Janeiro, RJ, Brazil AM116898 KC576607 [19] Ss261 - Sporothrix brasiliensis Human sporotrichosis Pelotas, RS, Brazil KC693894 KC576635 This study Ss265 CBS 133020 Sporothrix brasiliensis Human sporotrichosis Uberaba, MG, Brazil JN204360 KC576636 [12] Ss01 CBS 132961 Sporothrix schenckii Feline sporotrichosis São Paulo, SP, Brazil KC693828 KC576540 This study Ss02 CBS 132962 Sporothrix schenckii Human sporotrichosis Porto Alegre, RS, Brazil KC693829 KC576541 This study Ss03 CBS 132963 Sporothrix schenckii Human sporotrichosis Porto Alegre, RS, Brazil JX077117 KC576542 [11] Ss04 - Sporothrix schenckii Human sporotrichosis Porto Alegre, RS, Brazil JX077118 KC576543 [11] Ss13 - Sporothrix schenckii Human sporotrichosis Belo Horizonte, MG, Brazil KC693836 KC576551 This study Ss15 - Sporothrix schenckii Human sporotrichosis Belo Horizonte, MG, Brazil KC693837 KC576552 This study Ss17 - Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil KC693838 KC576553 This study Ss20 - Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil JX077119 KC576554 [11] Ss24 - Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil KC693839 KC576555 This study Ss26 CBS 132965 Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil KC693841 KC576557 This study Ss28 - Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil JX077121 KC576559 [11] Ss31 - Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil JX077122 KC576560 [11] Ss35 - Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil KC693842 KC576561 This study Ss36 - Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil KC693843 KC576562 This study Ss39 - Sporothrix schenckii Human sporotrichosis Curitiba, PR, Brazil JQ041899 KC576564 This study Ss63 CBS 132968 Sporothrix schenckii Human sporotrichosis Vila Velha, ES, Brazil JX077123 KC576573 [11] Ss64 - Sporothrix schenckii Human sporotrichosis Vila Velha, ES, Brazil JX077124 KC576574 [11] Ss73 - Sporothrix schenckii Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693853 KC576579 This study Ss75 - Sporothrix schenckii Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693854 KC576580 This study Ss78 - Sporothrix schenckii Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693855 KC576581 This study Ss80 CBS 132969 Sporothrix schenckii Human sporotrichosis Rio de Janeiro, RJ, Brazil JX077125 KC576583 [11] Ss90 - Sporothrix schenckii Human sporotrichosis Rio de Janeiro, RJ, Brazil KC693859 KC576586 This study Ss111 CBS 132971 Sporothrix schenckii Human sporotrichosis São Paulo, SP, Brazil KC693860 KC576587 This study Ss143 - Sporothrix schenckii Human sporotrichosis Belém, PA, Brazil JQ041903 KC576592 [11] CBS 359.36T CBS 359.36T Sporothrix schenckii Human sporotrichosis USA AM117437 KC576614 [19] CBS93872 CBS 93872 Sporothrix schenckii Human sporotrichosis France AM490340 KC576637 [17] Ss06 CBS 132922 Sporothrix globosa Human sporotrichosis Belo Horizonte, MG, Brazil JF811336 KC576545 [11] Ss41 CBS 132923 Sporothrix globosa Human sporotrichosis Fortaleza, CE, Brazil JF811337 KC576565 [11] Ss49 CBS 132924 Sporothrix globosa Human sporotrichosis Goiânia, GO, Brazil JF811338 KC576566 [11] CBS 120340T CBS 120340T Sporothrix globosa Human sporotrichosis Spain AM116908 KC576608 [19] CBS 130104 CBS 130104 Sporothrix globosa Human sporotrichosis Spain AM116905 KC576609 [19] Ss236 CBS 132925 Sporothrix globosa Human sporotrichosis Minas Gerais, MG, Brazil KC693877 KC576618 This study FMR 8598 CBS130116 Sporothrix globosa Human sporotrichosis Spain AM116903 KC576638 [19] CBS 937.72T CBS 937.72T Sporothrix luriei Human sporotrichosis South Africa AM747302 KC576615 [18] Ss132 CBS 132927 Sporothrix mexicana Human sporotrichosis São Paulo, SP, Brazil JF811340 KC576590 [11] Ss133 CBS 132928 Sporothrix mexicana Human sporotrichosis Recife, PE, Brazil JF811341 KC576591 [11] CBS 120342 CBS 120342 Sporothrix mexicana Vegetal Mexico AM398392 KC576610 [17] CBS 120341T CBS 120341T Sporothrix mexicana Soil Mexico AM398393 KC576611 [17] CBS 302.73T CBS 302.73T Sporothrix pallida Soil United Kingdom AM398396 KC576612 [17] CBS 111110 CBS 111110 Sporothrix pallida Insect Germany AM398382 KC576613 [17] CMW 304 CBS 141.36T Grosmannia serpens Environmental Italy JN135300 - [30] AFTOL-ID 910 CBS 158.74 Ophiostoma piliferum Environmental Chile - DQ471074 [31] 1 Calmodulin literature reference. IPEC, Instituto de Pesquisa Clínica Evandro Chagas, Fiocruz, Brazil; FMR, Facultat de Medicina i Ciències de la Salut, Reus, Spain; CBS, Centraalbureau voor Schimmelcultures, Utrecht, The Netherlands; KMU, Kanazawa Medical University, Ishikawa, Japan; CMW, Culture Collection of the Forestry and Agricultural Biotechnology Institute (FABI); AFTOL, Assembling the Fungal Tree of Life project; NK, not known; T , type strain. All “Ss” strains belong to the culture collection of Federal University of São Paulo (UNIFESP). MG, Minas Gerais; RS, Rio Grande do Sul; PR, Paraná; SP, São Paulo; RJ, Rio de Janeiro; ES, Espírito Santo; PA, Pará; CE, Ceará; GO, Goiás, PE, Pernambuco. Phenotypic characterization Morphological identification of cultures was performed according to Marimon et al. [17], [18] including vegetative growth on PDA media at 30, 35, 37 and 40°C, colony colors on corn meal agar (Difco Laboratories, Detroit, Mich.), assimilation profiles of raffinose, ribitol and sucrose, and microscopic morphology in vitro. Growth at different temperatures was measured according to Mesa-Arango et al. [27]: the percent growth inhibition (GI) was calculated at 37°C by the following formula [(colony diameter at 30°C – colony diameter at 37°C)/colony diameter at 30°C]×100. The GI was evaluated by analysis of variance/Tukey test using the GraphPad (GraphPad Prism v. 5.00 for Windows, San Diego California USA, www.graphpad.com), considering statistically significant when p 0.05 (no evidence of recombination). Also, DNAsp v5.1 [43] was used to evaluate minimum number of recombination events in the history and haplotypic diversity of S. brasiliensis population. The software computes the recombination parameter R = 4Nr, where N is the population size and r is the recombination rate per sequence -or between adjacent sites [44]. Ethics statement The animals included in this study were examined by a veterinarian with experience in small animal internal medicine. The procedures performed in these animals were approved by the Ethics in Research Committee (CEUA) of the FIOCRUZ, Rio de Janeiro, Brazil, under license number L-041/06. Results Our study included indoor and feral cats from five different geographic regions in Brazil (RJ, RS, MG, SP, and PR). Diagnosis of sporotrichosis was performed by the clinical evaluation of skin lesions and confirmed by isolation of the pathogen. The suspected colonies of Sporothrix species were grown on Mycosel agar until purification of the pathogen. The fungus was easily isolated from material from the nasal, oral mucosa and skin lesions. Lesions in the cephalic region and/or respiratory tract were observed in most of the animals (Fig. 2). 10.1371/journal.pntd.0002281.g002 Figure 2 Clinical aspects of feline sporotrichosis in Brazil. Cats presenting ulcerated cutaneous lesions in the cephalic region. (A) and (B) felines from Rio de Janeiro; (C) and (D) felines from Paraná. Phenotypic characterization, i.e. growth at various temperatures, macroscopic and microscopic features, and carbohydrate assimilation, yielded data similar to those found for the reference strains of S. brasiliensis (CBS 120339) and S. schenckii (CBS 359.36) reported by Marimon et al. [17]. Among the 33 strains of Sporothrix isolated from cats (n = 31) and dogs (n = 2) from different geographic regions of Brazil, 32 belonged to S. brasiliensis (96.9%) and 1 to S. schenckii (3%). These phenotypic results showed that S. brasiliensis is highly prevalent among cats with sporotrichosis. The two isolates recovered of canine sporotrichosis (CBS 132994 and CBS 133004 from RS and SP, respectively) were identified as S. brasiliensis. Using CL1 and CL2A primers we amplified 800 bp of the CAL locus. The complete alignment included 100 strains. Aligned sequences of CAL were 727 bp long, including 366 invariable characters, 214 variable parsimony-informative (29.43%), and 125 singletons. Comparison with sequences available at GenBank revealed a match of 99–100% with the type strain of S. brasiliensis (CBS 120339, AM116899) corroborating our phenotypic data. The single isolate of S. schenckii (CBS 132961) matched 99% with the S. schenckii s. str. strain (FMR 8678, AM117446) from Argentina. Phylogenetic analysis of isolates from cats and dogs revealed that S. brasiliensis is the prevalent species (32/33); only a single isolate clustered with S. schenckii s. str. The clade of pathogenic Sporothrix species was well supported with high bootstrap and posterior probability values. The S. brasiliensis isolates recovered from animal sources clustered in a single branch together with clinical isolates, indicating that they belonged to the same genotypes and confirming that the disease is transmitted by cats. A cryptic branch was observed in the S. brasiliensis clade composed of the isolates Ss27, Ss125, Ss128, CBS 132997, CBS 132999, CBS 133000, CBS 133001 CBS 133002 and CBS 133003, supported by bootstrap and posterior probabilities values (64/66/1) (Fig. 3A). 10.1371/journal.pntd.0002281.g003 Figure 3 Phylogenetic trees generated by Neighbor-joining, Maximum Likelihood and Bayesian analysis using partial nucleotide sequences of the calmodulin-encoding gene (A) and the translation elongation factor-1 alpha (EF1α) locus region (B). Bootstrap and posterior probabilities values were added to respective branches (NJ/ML/BI). Each species are indicated at each respective position at the phylogenetic tree. Calmodulin and EF1α accessions number are indicated in the Table 1. Sporothrix brasiliensis presented low genetic diversity compared to its sister taxon S. schenckii when CAL was used as a marker. Elongation factor (EF1α) was used as marker to assess the genetic diversity in the species. All isolates presented similar fragments of 850 bp of the EF1α locus which were amplified and sequenced with primers EF1-F and EF1-R. Aligned sequences of EF1α were 707 bp long, including 639 invariable characters, 34 variable parsimony-informative (5.08%), and 33 singletons. The 100 OTUs were distributed into 7 main groups (Fig. 3B), which were congruent with the CAL phylogeny. Judging from the EF1α dataset, the S. brasiliensis isolates recovered from animal sources in RJ and RS clustered in two branches with human clinical isolates from the same states, indicating two epidemics with distinct genotypes are concerned (Fig. 3B). Sporothrix brasiliensis presented low genetic diversity in EF1α, in accordance with results obtained for the CAL locus. The haplotype diversity of S. brasiliensis species was assessed using the DNASp software. Only 7 haplotypes for CAL (Fig. 4A) and 3 haplotypes for EF1α (Fig. 4B) were found. The low values of haplotype (HdCAL = 0.36 and HdEF1α = 0.37) and nucleotide diversities (πCAL = 0.00152 and πEF1α = 0.00062) lead us to hypothesize that this species is clonal (Table S1). Geographical separation between the RJ and RS epidemics for the EF1α locus was clear. The median-joining network based on the EF1α haplotype showed an intraspecific separation (Fig. 4B, haplotypes H11 and H12) resulting from a nucleotide transition from A to G, between isolates from RJ and RS epidemics (Table S2). The average divergence between S. brasiliensis and its sister species S. schenckii is much higher, suggesting that the species experienced different evolutionary processes. 10.1371/journal.pntd.0002281.g004 Figure 4 Median-joining haplotype network of Sporothrix schenckii complex isolates based on partial nucleotide sequences of the calmodulin-encoding gene (A) and the translation elongation factor-1 alpha (EF1α) loci regions (B). The EF1α haplotype showed a clear intraspecific separation resultant from a nucleotide transition from A to G, between S. brasiliensis isolates recovered from Rio de Janeiro (H9) and Rio Grande do Sul (H11 and H12) feline epidemics. The size of the circumference is proportional to the haplotype frequency. Black dots (median vectors) are hypothetical missing intermediates. Calmodulin and EF1α haplotypes are detailed in the Table S2. Recombination analysis of S. brasiliensis was first assessed by split decomposition method and no networks linking different isolates were observed in both datasets (Fig. 5), in agreement with the concept of clonal species. Also PHI-test analysis showed no evidence of recombination (pCAL = 0.757 and pEF1α = 0.903), and no recombination events were detected by DNAsp5 software. Taken together, these analyses indicated that S. brasiliensis is a clonal species. 10.1371/journal.pntd.0002281.g005 Figure 5 Split decomposition analysis of the Sporothrix brasiliensis isolates from zoonotic epidemic outbreaks in different geographic regions in Brazil according to sequences of the calmodulin-encoding gene (A) and the translation elongation factor-1 alpha (EF1α) locus region (B). The inset Box represents the S. brasiliensis species alone, showing the absence of recombination possibilities within this species. The absence of reticulated phylogenetic structure in the S. brasiliensis haplotypes suggests a clonality spread of this species among human, cats and dogs in Brazil for both loci. Aiming to evaluate possible phenotypic characteristics that explain the success of this pathogen adaptation to the feline host we evaluated the thermal resistance of strains of clinical interest (human and animal) and environmental strains. Strains of S. brasiliensis from feline origin (n = 30) showed highest temperature tolerance, being inhibited 77.1±6.32% on average at 37°C (Fig. 6). The group differed statistically from other species evaluated herein (S. schenckii s. str., S. globosa, and S. mexicana), suggesting that this factor may confer advantage during the process of infection in the feline host. 10.1371/journal.pntd.0002281.g006 Figure 6 In vitro temperature fitness in the Sporothrix species. Growth inhibition at 37°C compared to 30°C incubation. S. brasiliensis from feline (n = 30) or human source (n = 27) are more resistant to heat incubation and differ statistically when compared to S. schenckii (n = 25), S. globosa (n = 7) and S. mexicana (n = 4). Statistical significance in one-way ANOVAs followed by Tukey's tests: * p<0.05, *** p<0.0001. The line in the boxes and upper and lower bars show the median, maximum and minimum values, respectively. Isolates were not compared at superior temperature (38–40°C) due to low growth observed to S. globosa and S. mexicana. No isolate were able to growth at 40°C. Supporting information Supplementary information reported in this section is complementary to the results and describe the genetic diversity of the Sporothrix isolates. Discussion Epidemiology of fungal infections can be influenced by several factors, including: (i) biological factors such as fungal virulence and host resistance, (ii) ecological factors such as temperature, atmospheric humidity, ultraviolet radiation, geological conditions, and inter-relationships with other living beings, and (iii) socio-economic factors such as poverty, sanitation, clothing, profession, prophylactic habits and population migrations. In the Brazilian epidemic of feline sporotrichosis a combination of a highly virulent fungus and a susceptible host coupled to low sanitary conditions in the suburbs has made the state of RJ a highly endemic area of this mycosis among animals and humans. The epidemic proportions are noted only since the last two decades. Little is known about the eco-epidemiology of feline sporotrichosis and its impact on the epidemiology of human sporotrichosis. Cats play a significant role in outbreak areas of sporotrichosis such as RJ and RS. Classically, humans can acquire sporotrichosis by cat scratches or bites, the reason why cats are considered important source of infection in the spread of the disease. In our study we found that S. brasiliensis is the prevalent etiological agent of feline sporotrichosis in Brazil. Among cats, S. brasiliensis was identified in a total of 96.9% of the samples, by isolation of the pathogen from lesions and posterior phenotypic and molecular characterization. Interestingly, a correlation between cat outbreaks and prevalence of S. brasiliensis among humans was found in the same geographic area, such as in RJ (Table 1). This fact matches with our hypothesis that outbreaks among cats directly influence the prevalence of S. brasiliensis in human cases of sporotrichosis in the same geographic area. A similar situation was observed in the state of RS where S. brasiliensis was isolated with high frequency from cats as well as from humans. Marimon et al. [17] analyzed 127 Sporothrix isolates using the calmodulin locus and five major clades (I–V) were recognized. The maximum likelihood, neighbor-joining and Bayesian analyses based on the calmodulin (Fig. 3A) or EF1α (Fig. 3B) loci placed our animal Sporothrix isolates in Clade I (S. brasiliensis) composed of clinical samples from the RJ State epidemic, with strong bootstrap and posterior probability support. All pathogenic Sporothrix species are known to occur in Brazil [11], but S. brasiliensis is relatively frequent among feline sporotrichosis outbreaks. The geographic origin of S. brasiliensis of the Brazilian epidemic is difficult to establish. At least two distinct genotypes occur: one in RS and another in RJ. The latter is the oldest and longest recorded in the literature [3], [4], [23], [24]. Our data show that humans and animals infected in the RS epidemic harbor the same S. brasiliensis genotype, which is distinct from the one of the RJ epidemic. The RJ genotype is also present in the recent outbreaks in PR, MG and SP, which suggests spread of S. brasiliensis from RJ. Additionally, our results showed absence of recombination events in the CAL and EF1α loci, demonstrating that S. brasiliensis is a clonal species. Despite a recent indication of intraspecific variability within the species S. brasiliensis using RAPD [45] we believe that this phenomenon is not frequent or strong enough to break the prevalent pattern of clonal population structure, i.e., recombination or scarce exchange of genetic material may occur in some point of the evolutionary course of the pathogen life without compromise or affect its population structure. This hypothesis has been discussed by Tibayrenc and Ayala [46] through different group of pathogens including fungi. The existence of clonal populations has repeatedly been proven in fungal pathogens [47]–[50], although most of these species are surmised to have occasional sexuality in any phase of their life cycle. Under permissive conditions, most fungi reproduce very effectively by asexual propagation. Sexual reproduction provides advantages to the pathogen under adverse conditions, generating suitable genotypes that enhance survival. Many fungal epidemics are driven by populations showing low levels of genetic diversity, as demonstrated in Penicillium marneffei [51], [52], Cryptococcus gattii [53], [54] and Batrachochytrium dendrobatidis [55]. Also feline and human sporotrichosis in Brazil caused by S. brasiliensis is driven by the spread of a clonal species. In contrast, outbreaks of other human pathogens such as Coccidioides immitis [56]–[58] and Paracoccidioides brasiliensis [59]–[61], spread by a diversity of genotypes. The ecological aspects of the pathogenic species within the genus Sporothrix needs to be reevaluated, and this information can be crucial to find the source of S. brasiliensis in nature. Classically, soil [5], thorny plants [62], Sphagnum moss [63]–[65] and hay [66] have been pointed as source of S. schenckii s.l. To date, just a single environmental isolate (FMR 8337) of S. brasiliensis was isolated and reported from domiciliary dust in Brazil [17], [19]. Distant relatives of Sporothrix in the fungal order Ophiostomatales are mainly associates of bark beetles on woody plants [67], [68]. Zhou et al. [13] demonstrated that different ecologies are corroborated by phylogenetic separation. It is challenging to obtain environmental isolates of S. brasiliensis, and the low number of subjects contaminated with propagules from soil or woody plants is indeed low compared to the high occurrence in warm-blooded hosts [3], [69], [70]. This suggests successful transmission among animals (cat-cat and cat-humans). This scenario is different from epidemics occurring in South Africa [71], [72], India [10], [73], the USA [63], [64], Australia [66], [74], China [75], and Japan [76], where patients are mainly infected through soil and decaying wood. Possibly the Brazilian epidemics of S. brasiliensis are related to the emergence of a pathogenic clone front of a highly susceptible feline host, rather than to an increase in population size of S. brasiliensis in nature. This is corroborated by the high degree of virulence observed in naturally infected cats in the outbreak area [24], as well as demonstrated in a murine model [21]. Besides that, we do not discharge the hypothesis that the emergence of pathogenicity could also be attributed to a recent host-shift from an unknown host to cats as discussed in other groups of pathogens [77]–[79]. Feral cats present a great potential to spread the disease in a short period of time due to their mobility and digging behavior, whereas dispersal from soil or vegetable remains is ineffective. Classically, accumulation of mutations in fungal populations can lead to speciation processes. However, rapid emergence of a new, highly virulent pathogen which is able to explore different ecological niches may result from other processes than those observed in natural selection. In many plant-pathogenic fungi, such as Fusarium and Alternaria, pathogenicity is determined by mobile, dispensable small chromosomes [80], [81]. Genetic processes such as hybridization of two distinct, sympatric species [82], parasexual recombination [83], [84] or mechanisms of inactivation/activation of virulence genes by insertion of transposons [85] can also drive the emergence of pathogenicity. Hybridization is one of the possible mechanisms of emergence of phytopathogenic fungi [86], [87] as well as fungi pathogenic to animals [88]. It has also been discussed in the genus Ophiostoma, which is phylogenetically related genus to Sporothrix [89]. All these genetic processes, alone or in combination, may be the reason of the emergence of virulence in the species S. brasiliensis. The lack of variation in the populations of S. brasiliensis also may be the result of a strong selective pressure imposed by the feline host. Presence of opposite mating types and sexual reproduction leads to genetic recombination and may increase fitness and widen host ranges. So far, no evidence of sexual recombination was demonstrated experimentally for the species from the S. schenckii complex and this fact, combined with the hostile selective pressure of the cats may provide possible explanations for the lack of diversity in S. brasiliensis. The association of S. brasiliensis with cats may play an important role in the evolution and spread of this pathogen. The interaction between cats and S. brasiliensis is not an exclusive relationship, since S. schenckii s. str. was also found in the feline host. However, S. brasiliensis has become predominant in this host within less than a decade, indirectly indicating a recent adaptation to the conditions of the feline body. Therefore, cats represent a natural habitat for S. brasiliensis. In contrast to the situation in opportunistic fungi, Sporothrix species are able to escape from the host and be transmitted to the next host, which is one of the hallmarks of a pathogen. Transmission is either direct during fights, or indirect, the fungus returning to soil after the cat has died. Given the role of the mammal host in Sporothrix evolution, variance in fitness between clonal lineages of S. brasiliensis is expected to lead to populations that are better adapted to host conditions. For example, the body temperature of the feral cat Felis catus is around 38–39°C, depending on its activity [90]. Interestingly, S. brasiliensis has the best rate of vegetative growth when incubated at 37°C, followed by S. schenckii s. str. (Fig. 6). Remaining species of Sporothrix such as S. globosa and S. mexicana appear to be more sensitive to temperature, having a maximum around 35°C. The cat's body temperature could be considered an important selective pressure event, selecting thermo-resistant strains during sporotrichosis outbreak episodes. Transmission of S. brasiliensis by cats promotes inoculation into human hosts of yeast cells of rather than of hyphae and conidia, yeast cells having been reported to be more virulent [6]. The endotherm developed by mammals is a natural defense mechanism against pathogens [91]–[93], and in our study this factor appears to restrict the occurrence of species of the S. schenckii complex that are sensitive to temperatures above 35–37°C [11], [17]. Another important factor in understanding the success of the epidemic of sporotrichosis among cats in RJ, has a socio-economic character. Most cat owners are living in neglected areas and many abandon dead animals in the street [94], favoring contact with other feral cats, or simply bury their pets after death in their backyard or in nearby wastelands. This directly allows the return of the agent into the environment, increasing outbreak risks of the pathogen, and enhancing the spread of the clonal species. In an epidemic scenario, domestic pets such as cats and dogs are the first animals to become infected with the fungus. Subsequently human cases of sporotrichosis are likely to emerge. Thus, we believe that cats can act as sentinel animals for epidemiological services, and its notification should be compulsory by regulatory agencies as the Centers for Zoonosis Control. The predominance of a species that is highly virulent to humans and animals requires fast implementation of public health policies to contain the epidemic, lowering harmful effects to the population. Supporting Information Table S1 Nucleotide diversity (%π) and haplotype diversity (1 – Σfi2) from Brazilian clinical isolates belonging to the Sporothrix schenckii complex. (DOC) Click here for additional data file. Table S2 Identification of the haplotypes in the Sporothrix species according to the calmodulin (CAL) or elongation factor (EF1-α) loci. (DOC) Click here for additional data file.
Author and article information
Journal
Journal ID (nlm-ta): Dermatol Res Pract
Journal ID (iso-abbrev): Dermatol Res Pract
Journal ID (publisher-id): DRP
Title:
Dermatology Research and Practice
Publisher:
Hindawi Publishing Corporation
ISSN
(Print):
1687-6105
ISSN
(Electronic):
1687-6113
Publication date
(Print):
2014
Publication date
(Electronic):
29
December
2014
Volume: 2014
Electronic Location Identifier: 272376
Affiliations
Author notes
Article
DOI: 10.1155/2014/272376
PMC ID: 4295339
PubMed ID: 25614735
SO-VID: 4d5ea51b-9c7f-4600-9797-c4aae16cba50
Copyright © Copyright © 2014 Vikram K. Mahajan.
License:
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
History
Date
received
: 30
July
2014
Date
accepted
: 12
December
2014
Categories
Subject:
Review Article
ScienceOpen disciplines: Dermatology
Data availability:
ScienceOpen disciplines: Dermatology