462 DISEASES OF THE SKIN. 



The treatment of phlegmonous erysipelas, and of boils and carbun 

 des, we refer to the handbooks of surgery. 



CHAPTER V. 



HERPES ACUTE SUPERFICIAL DERMATITIS, ATTENDED BY FORMATION 

 OF GROUPS OF VESICLES UPON THE SKIN. 



ETIOLOGY. Herpes closely resembles erysipelas, in being an acute 

 dermatitis arising from unknown causes. It differs from it, however, 

 both in the abruptness of the limits of the inflammation and in its seat, 

 which is confined exclusively to the most superficial layers of the skin. 

 Hebra defines the various forms of herpes as " a series of acute cuta- 

 neous diseases of cyclical course, marked by an exudation which col- 

 lects in drops under the epidermis and elevates it ; forming vesicles 

 which are never solitary but always appear in groups." These vesi- 

 cles are all of about the same size and shape. The various groups do 

 not appear simultaneously, but follow one another at intervals of sev- 

 eral days, so that crops of recent vesicles and of older declining ones 

 are usually to be found at the same time. Eruptions of herpetic vesi- 

 cles (called hydroa febriles) often appear upon the face, and especially 

 upon the lips of patients suffering from pneumonia, intermittent fever, 

 ephemera, and epidemic cerebro-spinal meningitis. This eruption is 

 hardly ever seen in other diseases, particularly in typhoid fever (typhus 

 abdominalis). The appearance of herpes upon the face in acute febrile 

 disease has long been regarded as a favorable prognostic sign ; perhaps 

 merely because the diseases, to which it is almost peculiar, recover 

 more frequently than those in which it is rarely or never seen. Her- 

 petic eruptions, however, occur also in individuals previously healthy, 

 as well as during the course of other diseases. 



It may be regarded as established that herpes zoster depends upon 

 disease of the trophical fibres of the motor and sensory nerves, which 

 supply the part affected. Further confirmation is required of the sup- 

 position that all forms of herpes are of similar origin ; for instance, 

 that herpes labialis proceeds from disease of small nervous branches 

 in the lips. 



SYMPTOMS AND COURSE. According to the region attacked, herpes 

 is classified into, first, herpes labialis, which is situated upon the lips, 

 and which often extends to the mucous membrane of the mouth. When 

 the groups of vesicles appear upon some other part of the face, such as 

 the cheeks or eyelids, it is called herpes phlyctenodes. Hebra pro- 

 poses the name of herpes facialis for all forms of herpes appearing 

 upon the face. There is also a herpes preputialis, which, as it likewise 





