ECTHYMA. 481 



or oiner grease, when they grow too thick and hard, and to removing 

 them with a poultice. But, if the disease already have lasted for 

 weeks or months, expectant treatment is no longer appropriate, and 

 we must consider whether to treat the disease locally or generally, 

 according to the principles laid down in the previous chapter. The 

 latter is more frequently indicated in impetigo than in eczema, as this 

 form of dermatitis often constitutes one of the symptoms of a consti- 

 tutional disease. In the treatment of impetigo, as a rule, the same 

 local remedies may be employed which have already been proposed 

 for the treatment of eczema. The disease, however, is not so tolerant 

 of strongly irritating applications as eczema is, on account of its more 

 inflammatory character, as is shown by the suppuration which charac- 

 terizes it. White precipitate, the oxide and the sulphate of zinc, and 

 slight cauterization, with nitrate of silver, are usually to be preferred to 

 the preparations of sulphur, the soft soap, and tar. 



CHAPTER IX. 



ECTHYMA DERMATITIS, WITH FORMATION OF LAEGE, ISOLATED, PER- 

 MANENT PUSTULES. 



ETIOLOGY. Although the pustules of ecthyma always arise from a 

 brightly-reddened, swollen, and infiltrated base, yet, in spite of the in- 

 tensity of the inflammation, the suppuration is usually confined to the 

 surface of the cutis, and is not apt to involve its parenchyma. In the 

 latter case only does ecthyma cause ulceration of the skin, and produce 

 scars, owing to contraction of the young connective-tissue cells by which 

 the loss of substance is supplied. 



Ecthyma often proceeds from direct irritation of the skin. The 

 pustules caused by tartar-emetic ointment (ecthyma antimoniale), and 

 those which appear upon the hands and arms of smiths and masons, 

 from the contact of lime, or of detached particles of red-hot iron, are 

 of this class, as well as the large pustules which arise from the violent 

 scratching provoked by the presence of parasites, or by the itching of 

 other eruptions. In other instances, ecthyma arises without any ap- 

 preciable previous irritation during the course of febrile diseases, assum- 

 ing a form somewhat analogous to what is generally called hydroa 

 febrilis. Finally, ecthyma is also seen in persons broken down by 

 privation, or other cause of exhaustion, or who have become cachectic 

 by a physical drain upon the system, by severe or tedious illness, and 

 by an abode in prisons, or in other unwholesome dwellings ; as well 

 as among drunkards and in scorbutic individuals. We shall treat of 

 syphilitic ecthyma hereafter. 



