Blastomycosis

There are 3 main types of deep blastomycosis: North American Gilchrist blastomycosis; European blastomycosis Busse-Buschke; South American blastomycosis. The names “North American” and “European” do not correspond to the geographical distribution of these diseases; in fact, they are observed in many countries around the world.

Gilchrist's blastomycosis is a chronic disease related to deep mycoses, characterized by the formation of granulomas and purulent processes in the lungs, skin, subcutaneous tissue, and, with dissemination, in many internal organs.

The causative agent - Blastqmyces dematifidis - is one of the two-phase fungi. In tissues it has the appearance of round yeast-like cells with a diameter of 8-15 microns; colonies of white, later brownish color, consisting mainly of mycelial filaments, are formed on Sabouraud's nutrient medium.

The sources and routes of transmission of infection have not been sufficiently studied. The portal of infection is probably the respiratory tract, as evidenced by the predominant lesions of the respiratory organs. Skin lesions, which are also often observed in patients, are secondary as a result of infection from the lungs (localized mainly in closed areas of the skin). When the infection generalizes, the pathogen from the lungs enters various organs (bones, liver, spleen, central nervous system). As a result of the infection, allergic restructuring develops, and blastomycosis leaves a long-lasting and lasting immunity.

Busse-Buschke blastomycosis (cryptococcosis) is a subacute or chronic deep mycosis characterized by a severe course with predominant damage to the central nervous system, less commonly the lungs, skin and mucous membranes.

The causative agent is Cryptococcus neoformans. In pathological material, it appears as round yeast cells with a diameter of 3~10 µm, surrounded by a transparent gelatinous capsule up to 50 µm wide. Does not form mycelium.

South American blastomycosis (paracoccidioidomycosis, paracoccidioidosis, Brazilian blastomycosis) is a deep mycosis characterized by a chronic progressive course, ulcerative granulomatous lesions of the skin, mucous membranes and internal organs, mainly the lungs.

The pathogen belongs to two-phase fungi; in tissues in the form of budding cells (10-50 microns), forms mycelium on nutrient media. Found in rural areas with tropical and subtropical climates. The mucous membrane of the mouth and nose is primarily affected, ulcers with a granulomatous bottom appear, slowly increasing in size, the tongue and vocal cords can be destroyed, and teeth fall out. The skin is involved in the process for the second time (the process moves from the mucous membranes), regional lymph nodes are affected, the process can involve the lungs (the process resembles pulmonary tuberculosis), intestines, bones, and less often the central nervous system.

The diagnosis is confirmed by detection of the fungus in granulation tissue (scraping) or in sputum. Treatment - see Blastomycosis Gilchrist. The prognosis is favorable.