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ACTINOMYCOSIS (STREPTOTRICHOSIS)
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See also:ACTINOMYCOSIS (STREPTOTRICHOSIS) , a chronic infective disease occurring in both See also:cattle and See also:man. In both these See also:groups it presents the same clinical course, being characterized by chronic inflammation with the formation of granulomatous tumours, which tend to undergo suppuration, fibrosis or calcification. It used to be believed that this disease was caused by a single See also:vegetable See also:parasite, the See also:Ray-Fungus, but there is now an overwhelming See also:mass of observations to show that the clinical features may be produced by a number of different See also:species of parasites, for which the generic name Streptothrix has been generally adopted. In 1899 the See also:committee of the Pathological Society of See also:London recommended that the See also:term Streptotrichosis should be used as the appropriate clinical epithet of the large class of Streptothrix infections. And since that See also:year the name Actinomycosis has been falling into disuse, and in any See also:case is only used synonymously with Streptotrichosis. For a further See also:account of these parasites see the articles on See also:BACTERIOLOGY and on PARASITIC DISEASES. Pathological See also:Anatomy.—The naked-See also:eye See also:appearance of the different See also:organs affected by Streptothrix infection varies according to the duration and acuteness of the- disease. In some tissues the appearance is that of See also:simple inflammation, whereas in others it may be characteristic. The See also:liver when affected shows scattered foci of suppuration, which may become aggregated into spheroidal masses, surrounded by a See also:zone of inflammation. In the lungs the changes may be any that are produced by the following conditions. (I) An acute See also:bronchitis. (2) A phthisical See also:lung, See also:grey nodules being scattered here and there almost exactly simulating tuberculous nodules. (3) An acute broncho-See also:pneumonia with some interstitial fibrosis and a tendency to See also:abscess formation. The most characteristic lesions are in the skin. These appear as nodules, sarcomatous-looking, soft and pulpy. Their See also:colour is mottled, yellow and purplish red. The skin over them is thinned out, and broken down in places to See also:form one or two crateriform ulcers from which a clear sticky fluid exudes. The See also:size varies from that of a See also:pea to a small See also:orange. The pus is characteristic, varying in consistency though usually viscid, and containing numerous See also:minute specks. The disease is more See also:common in See also:males than in See also:females, and more prevalent in See also:Germany and See also:Russia than in See also:England. The infection is probably spread by See also:grain (See also:corn or See also:barley), on which the fungus may often be found. In a See also:great number of recorded cases the patient has been following agricultural pursuits. The disease can only be transmitted from one individual to another with considerable difficulty, and no case of See also:direct transmission from See also:animal to man has yet been noted. Clinical See also:History.-The course of actinomycosis is usually a chronic one, but occasionally the fungus gets into the See also:blood, when the course is that of an acute infective disease or even pyaemia. The symptoms are entirely dependent on the See also:organ attacked, and are in no way specially characteristic. During See also:life a diagnosis of See also:phthisis is continually made, and only a microscopic examination after See also:death renders the true nature of the disease apparent. The nature of the skin "See also:lesion is the most evident, and here the parasite can be detected See also:early in the illness. The,- only See also:drug which appears to have any beneficial See also:influence on the course of the disease is See also:potassium iodide, and this has occasionally been used with great benefit. Surgical interference is usually needed, either excision of the See also:part affected, or, where possible, a thorough scraping of the lesion and See also:free application of See also:antiseptics. Additional information and CommentsThere are no comments yet for this article.
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