48 CLINICAL DIAGNOSTICS. 



the most common]. Leucemia and anemia are frequently- 

 attended \vith skin dropsies. 



c. Inflammatory edema (collateral edema) also pro- 

 duces swellings of the skin, but this is usually local. It is 

 characterized by pain and increased warmth. In one form 

 of anthrax appears a circumscribed, hot, hard, painful tumor 

 on the neck, head, or body — the malignant carbuncle. 



In some of the infectious diseases a more or less diffuse, 

 or a multiple inflammatory edema, becomes manifest ; in in- 

 fluenza of the horse the eyelids, scrotum and limbs swell ; in 

 purpura hemorrhagica multiple, later diffuse tumefactions 

 occur on the head, prepuce, lower abdomen, and limbs. [Leg 

 swellings in purpura are characterized by their abrupt, bolster- 

 like, termination]. A local, hot, edematous swelling often 

 betrays the presence of deep-lying inflammation — pus, and is 

 therefore important in diagnosis. In s t r a n g 1 e s of horses 

 suppuration in unavailable lymph glands is determined by the 

 accompanying edema of the skin in the region of the throat; 

 in glanders it occurs about the farcy bud ; in traumatic 

 peritonitis of cattle a hot, doughy swelling appears in 

 the hypochondrium. 



Emphysema of the skin. Emphysema of the 

 skin signifies the presence of air in the subcutaneous tissue. 

 Such swellings crackle on palpation and are usually zn'cll de- 

 fined. The contained air can be temporarily displaced by 

 applying pressure to parts of the swelling, but as soon as the 

 pressure is released the space caused by it refills. 



Emphysema originating spont^aneously is infrequent. It 

 is mostly due to the formation of gas in decomposing blood 

 extra vasates or retained abscesses {empli. scpticum). Spon- 

 taneous emphysema is pathognomonic of symptomatic anthrax, 

 black leg, where it appears upon the back, neck, and muscular 

 portions of the legs. 



Emphysema occurs most frequently from the aspiration 

 of air from without into the subcutis. The air may enter 



