DIFFERENTIAL DIAGNOSIS 215 



known as scirrhous cord seems to be due in rare cases to an 

 infection by the ray fungus. One such case has occurred in the 

 clinic of this institution. A very few ca.ses of this disease 

 have been reported in sheep the lesions being restricted to the 

 lungs or muscles. 



§ 167. Differential diagnosis. In cattle actinomycosis 

 is to be differentiated (i) from tuberculosis, especiall}' of the 

 lungs, glands about the throat, head and the udder, (2) vari- 

 ous forms of glossitis, polypoid, growths in the pharynx, 

 fibroma, sarcoma and osteosarcoma of the jaw, parotitis and 

 •cellulitis. The writer has seen a few cases of bacterial infec- 

 tion of the maxillary glands giving rise to the formation of 

 large quantities of caseous matter which caused swelling and 

 firmness suggestive of actinomycotic tumors. In one instance 

 a specimen reported to be actinomycosis was examined and 

 found to contain a piece of bone about three inches long which 

 bad become wedged between the teeth and cheek and sur- 

 rounded by infiammator}' tissues. Frohner calls attention to 

 contagious pleuro-pneumonia and foot and mouth disease as 

 possibly being mistaken for this disease. 



In making a positive diagnosis of actinomycosis it is 

 necessary to make a microscopic examination of some of the 

 ■diseased tissue or of the discharged pus in which the ray 

 fungus may be found if the disease is actinomycosis. It is 

 impossible to obtain this positive proof from the living animal 

 when the disease is situated in the internal organs. With 

 these it is necessar}- to depend largeh' upon the history and 

 general condition of the animal. In preparing the discharged 

 pus for a microscopic examination it is usuall}' sufficient to 

 crush one or more of the yellowish granules between a slide 

 and cover-glass. It is of advantage to wash it with a dilute 

 solution of caustic soda to clear awa}' the pus cells. The ro- 

 setts are easily recognized with a low magnification. 



In man, actinomycosis is to be differentiated from certain 

 forms of tuberculosis and the Madura foot disease which was 

 described by Carter, in i860, as a "fungous disease." This 

 is a chronic, locally spreading inflammation of the foot, rarely 

 •of the hand, causing the destruction of the part involved and 



