The fungus is usually isolated in the soil in its mycelial form wet earth that has been enriched with animal droppings, rotting wood, and other. DESCRIPCION La blastomicosis es una enfermedad infecciosa de rara ocurrencia, Los animales, como los perros y gatos, también pueden ser infectados. La búsqueda se efectuó con las palabras clave: blastomicosis, enfermedad de Gilchrist, Blastomyces dermatitidis y México. Una vez localizada la literatura.
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Blastomyces dermatitidis is the causal agent of blastomycosisan invasive and often serious fungal infection found occasionally in humans and other animals in regions where the fungus is endemic.
The fungus is endemic to parts of eastern North America, particularly boreal northern Ontariosoutheastern ManitobaQuebec south of the St. Lawrence River balstomicosis, parts of the U. Appalachian mountains and interconnected eastern mountain chains, the west bank of Lake Michiganthe state of Wisconsinand the animalfs Mississippi Valley including the valleys of some major tributaries such as the Ohio River.
In addition, it occurs rarely in Africa both north and south of the Sahara Desertas well as in the Arabian Peninsula and the Indian subcontinent.
In an infected human or animal, however, it converts in growth form and becomes a blsatomicosis budding yeast. Blastomyces dermatitidis is the causal agent of blastomycosisa potentially very serious disease that typically begins with a characteristically subtle pneumonia-like infection that may progress, after 1—6 months, to a disseminated phase that causes lesions to form in capillary beds throughout the body, most notably the skin, internal organs, central nervous system and bone marrow.
Blastomyces dermatitidis is the name applied to the ascomycetous fungusAjellomyces dermatitidis. Ina second species was described blastomicoais the genus BlastomycesB.
This is epidemiologically important for two reasons: This habitat is as yet unknown. In its asexual form, the fungus grows as a typical colonial microfungus, comparable to Penicillium or Rhizopus mold forms commonly seen on mouldy bread.
These conidia are probably the main infectious particles produced by the fungus.
They form on individual short stalks and readily become airborne when the colony is disturbed; their size places them well within the respirable size range for particles,  meaning that they can deposit deeply in the lungs when inhaled. The ascospores, at 1. One blastomicoss the unexplained regularities of nature is that there are several fungi of different phylogenetic ancestry that show a similar pattern of existence: Blastomyces dermatitidis is one blastomicossis these fungi; the others are Histoplasma capsulatumParacoccidioides brasiliensisCoccidioides immitisC.
The geographic range of B. Lawrence and Mississippi River systems of North America.
There is a widely distributed and much republished, partially erroneous map that shows the U. Lawrence River in Quebec, as well as high endemicity along the north shore of Lake Erie and the low endemicity in southeastern corner of Manitoba. Though the Quebec distribution is reasonably accurate, the rest of Canada is strongly misrepresented.
Blastomyces dermatitidis is absent or nearly so from amimales Lake Erie area, but occurs sporadically on the north shore of Lake Ontarioincluding metropolitan Toronto,  and, most notably, has areas of high endemicity throughout northern Ontario. In the rest of the world, B. The African isolates wnimales divided into two biologically different antigen groups: The sub-Saharan African isolates differ in the laboratory from other isolates by being exceedingly difficult to blastomicoais to the yeast phase, and they also show some enzymatic distinctions.
Blastomyces dermatitidis is one of the most ecologically mysterious organisms causing human and animal disease. Prediction of disease risk and prevention of disease are both made extraordinarily difficult by our very poor understanding of where and how this organism normally grows in nature. Despite decades of attempts at isolating organisms from epidemiological foci, B.
Needless to say, the cost and complexity of performing such studies is imposing, especially as the ethical clearance procedures for work involving animals become ever more involved. More direct and economical mycological techniques blastomicsois environmental isolation, such as dilution plating, have never yielded positive results for Blastomyces growth. In just one experiment, a single positive B. What has been learned from direct isolation and recent PCR studies is that B.
There has been a long history of justifiable speculation that B. To date, however, all the animal species that have been subjected to focused investigation have been exonerated of this specific connection. Unsubstantiated suspicion has particularly focused on the beaver,    but the shrew,  the bat  and the prairie dog  have also been blawtomicosis points of interest, with no conclusive interspecies association being blastokicosis to date. The closely related pathogenic fungus P.
Avoidance of exposure in animalds areas is the principal means of disease prevention. Because the agent is known to distribute animles dusts, the minimization of dust-generating activities, such as digging, sweeping, etc.
Blastomycosis and HIV
Although a method of soil decontamination has been described and demonstrated to be effective, it uses hazardous chemicals and its use is best reserved for situations that cannot be managed otherwise. From Wikipedia, the free blastomicoiss. Blastomyces dermatitidis Blastomyces dermatitidisyeast form Scientific classification Kingdom: Ecology of Blastomyces dermatitidis. Journal of Clinical Microbiology. Size-selective health hazard sampling.
Canadian Medical Association Journal.
Canada Communicable Disease Report. The Western Journal of Medicine. Soil decontamination and other control measures.
Blastomyces dermatitidisyeast form.