Observations on the roentgen patterns in blastomycosis of bone. A review of cases from the Blastomycosis Cooperative Study of the Veterans Administration and Duke University Medical Center.

Blastomyces dermatitidis in fections are characterized by an inflammatory reaction which may be suppurative, granulomatous, or a mixture of these two types. Virtually any organ of the body may be involved; signs and symptoms of this infection may be protean in their manifestations. Until recently the disease was believed to be restricted to the North American continent. Recently documented au tochthonous cases have been reported from South Africa, Uganda, the Congo, Mulago, Venezuela, and Mexico.2’18 Thus the designation “North American blastomycosis” no longer appears appropriate for this disease. In the United States the disease may be found in most areas. However, the greatest concentrations of cases are found along the Ohio Valley, the Mississippi Valley, and in the middle Atlantic States.32 Relatively few cases are observed in the midwestern and! western States.” It is interesting that canine and human cases follow similar geographic patterns.8 Although the majority of infections occur in patients of the 20 to 50 year age group, cases have been reported at all ages. There is no racial predilection; racial rates reflect the population of the particular area. Males are more often infected than females. Usually a history of contact with soil or soil products can be elicited.7-’1’23-24 Epidemiologic studies have all indicated that infection is acquired! by inhalation of spores from the soil, similar to histoplasmosis, coccidioidomycosis, and other fungus infections. The recent isolations of B/astomyce3 dermatitidis from soil appear to verify the epidemiologic theory.2”4-” The infection is required directly from soil by man or dog. Animal-to-animal and animal-to-human transmission has not been observed. Proc-know2’ has reported an instance of presumed human-to-hum an transmission. A few documented cases of primary cutaneous blastomycosis have been reported;3’ all were inoculated by accidental trauma to the skin by contaminated instruments while performing autopsies on cases of blastomycosis.