Aspergillus

ASPERGILLUS Mich., aspergillus, a genus of fungi from the order Plectascineae, subclass Ascomycetes (see). Widespread mold fungi with a septate mycelium, on the surface of which numerous unicellular conidiophores are formed in abundance; their club-like swollen ends segregate along the radius long, moniliform chains of small spherical conidia (spores), easily carried away by the slightest movements of the air.

They form mold coatings of various colors on all kinds of organic substrates, depending on the color of the conidia. The main fructification, perithecia, is formed mostly rarely and is not known for all species. Perithecia have the appearance of small, completely closed spheres formed by tightly intertwined and fused hyphae and enclosing numerous asci with ascospores. Some species form small, dense, spherical sclerotia. Most frequently encountered are A. glaucus and A. repens, which form blue-green mold coatings, and A. niger (=Sterigmatocystis niger), which forms black ones. A number of species, including common saprophytes (A. fumigatus, flavus, niger, nidulans, malignus), can be pathogenic for humans and higher animals. Recently, new pathogenic species have been described: A. Grotioti Sartory, A. Fontoynonti Gueguen, and A. Jeanselmi Ota (see Mycoses, Pneumomycosis). A. oryzae, which converts starch into sugar, has technical application in Japan for the preparation of rice vodka "sake". L. Kurganov. Aspergilloses. Representatives of the genus Aspergillus are the causative agents of a number of diseases in mammals, birds, reptiles, etc., and they possess the ability to form spores even in a living organism. When Aspergillus is injected under the skin of laboratory animals, chronic abscesses are formed, whereas injection into the blood or peritoneal cavity results in a general disease with the formation of nodules and small hemorrhages in various organs. It should be pointed out here that certain species of Aspergillus (as proved by Lucet and Rogers) produce a special toxin. Ceni and Besta managed to obtain this toxin from Aspergillus fumigatus and Aspergillus flavescens. The effect of this toxin was particularly pronounced on nerve and muscle tissues. As shown by the studies of Bodin and Gantier, this toxin is very resistant to high temperatures and is not destroyed even when heated to 120° for half an hour. More than 10 species of this fungus are pathogenic for humans, causing pathological processes in the skin, mucous membranes, and respiratory organs. These fungi are also the causative agents of special tumors—the so-called mycetomas (mycetoma)—which develop most frequently on the lower extremities. Settling in bronchiectases and cavities in tuberculosis or on ulcerated surfaces, Aspergillus greatly worsens the course of diseases and has a disastrous effect on their outcome. - Aspergillus of the eye. Independent eye diseases accompanied by ulcers on the cornea, caused by the fungus Aspergillus fumigatus, are described in the literature. - Aspergillus of the ear. In rare cases, fungi of the species A. fumigatus, A. repens, and A. malignus can be the causative agents of purulent inflammation of the middle and external ear, or else, multiplying in the ear canal, can complicate the course of otitis caused by other causes. Clinically, the disease is accompanied by severe itching and pain in the ear, dizziness, deafness, and other common symptoms of otitis. - Abscesses of aspergillosis origin. In multiple abscesses in a European in Madagascar, spores and mycelium of the fungus Aspergillus were found in the pus. - Pulmonary and bronchial aspergillosis is encountered predominantly in persons forced by the nature of their occupations to come into close contact with material containing the spores of these fungi, and is of interest as an occupational disease. Thus, around Paris there are whole villages engaged in the fattening of pigeons, and this feeding is carried out in the following manner: the peasants take a mixture of equal parts of millet, vetch, and water into their mouths and then, opening the pigeon's beak, feed it directly from the mouth. Experienced professionals manage to feed up to 4,000 pigeons a day. Since the spores of the fungus are very often found in cereal grains, it is natural that infection is frequently observed in this process. Pulmonary aspergillosis is often encountered among hair carders who sort hair collected by ragpickers in garbage cans, etc., and subject it to cleaning. In the process of cleaning, one has to resort to dusting dirty hair with rye flour, in which Aspergillus spores are very frequent. In the rooms where hair cleaning takes place, dust and fungal spores float in the air, which enter the lungs upon inhalation and give rise to a chronic inflammatory process of the lungs. In general, fungal diseases of the lungs are chronic in nature and resemble tuberculosis in their course. As regards the treatment of aspergillosis, preparations of iodine and arsenic sometimes give good results. Among animals, birds and dogs are very susceptible to pulmonary aspergillosis and die quickly from this disease. Cats, apparently, are insusceptible (Guiart). - Aspergillosis splenomegaly. Recently, cases of splenomegaly have been described in the etiology of which fungi of the species Aspergillus and Mucor undoubtedly played a role. Fungal splenomegaly was first described by Pinoy and Nante, who, upon autopsy of corpses with sharply enlarged spleens, discovered small, yellowish-colored nodules in the latter. Upon microscopic examination, these turned out to consist of Aspergillus mycelium and spores surrounded by granulation tissue with giant cells. Many mycelial threads were impregnated with lime salts. Recently, several cases of such splenomegaly have been detected in Moscow (see also Banti's disease). Prophylaxis of aspergillosis. To prevent the incidence of aspergillosis, it is first of all necessary to widely acquaint the population with the conditions of infection. In industries associated with a large amount of dust, room ventilation and the installation of vacuum cleaners where possible are necessary. It is also necessary to observe hygiene of the entire body to avoid skin diseases of an aspergillosis character.

E. Martsinovsky