456 DISEASES OF THE SKIN. 



CHAPTER IV. 



ERYSIPELATOUS DERMATITIS ERYSIPELAS. 



ETIOLOGY. Erysipelatous dermatitis is distinguished by an intense 

 hyperaemia of the cutis, and by a profuse serous transudation, not only 

 into the skin itself, but into the subcutaneous areolar tissue, and some- 

 times between the cutis and the epidermis. It is also marked by the 

 slightness of its tendency to form abscesses, and by the invariable im- 

 plication of the lymphatic vessels and glands in the inflammation. 

 Erysipelas not unfrequently results in rupture of small vessels and of 

 haemorrhages into the skin and upon its free surface. The disease is 

 sometimes so violent as to end in gangrene. 



I believe that it is an error to suppose that any cutaneous irritant, 

 if of sufficient intensity, may produce erysipelas. Comparison of ery- 

 sipelatous inflammation with that caused by a blistering plaster, in 

 spite of the blisters which may form in either case, seems to me de- 

 cidedly to contradict the identity of the two processes. Besides, the 

 inflammatory derangements of nutrition produced by burns and by me- 

 chanical injuries, and similar sources of local irritation, do not present 

 the characteristics of erysipelas, as they either produce simple blisters 

 without any other exudation either in the skin or under it, or else, 

 when of greater intensity, cause destructive disease of the part. We 

 may regard it as proved that most forms of erysipelatous dermatitis 

 proceed from the extension of an inflammation from the wall of an 

 inflamed lymphatic vessel into the surrounding tissue of the cutis. 

 First among these forms is that resulting from inoculation with some 

 acrid or venomous material. In such cases it can often be demon- 

 strated by direct observation that the poison was first taken up by the 

 lymphatics, and thus gave rise to inflammation of their walls, and 

 that the inflammation of the skin is a secondary occurrence. Here a 

 reddened cord, with nodular enlargements, is first observed, and 

 it is not until afterward that a diffuse and uniform redness and 

 swelling make their appearance upon the skin. Next to this form 

 comes the erysipelas, arising from the absorption of the ichorous se- 

 cretion of a wound, or of the putrid contents of an abscess by the lym- 

 phatics, and their consequent inflammation. Not to encroach too far 

 upon the province of surgery, I will merely call to mind the so-called 

 " tooth-rose." This consists in a dermatitis with all the peculiarities 

 of erysipelas ; and there can hardly be any doubt that it proceeds 

 from the extension of a lymphangitis to the skin, and that it is caused 

 by the absorption of the liquid from the fcetid contents of a gumboil. 

 The simplest explanation, for the fact that, in hospitals, erysipelas now 



