XXXIX.— ECZEMA IN THE DOG (CONCLUSION). 



Chronic eczema, which is very common in old dogs, succeeds to 

 acute attacks ; or may develop as a primary condition, and then pre- 

 sents the characters of the squamous form. 



It also most frequently affects the upper regions of the body ; in 

 some patients it is confined to the limbs, and more particularly to the 

 elbows and hocks. It may continue in the dry stage indefinitely, 

 though, as pruritus is generally severe, certain spots are apt to become 

 irritated by scratching or rubbing, and moist discharging areas develop 

 in consequence. For this reason most animals with old-standing 

 eczema show recent areas alongside others of much older standing. 



The affected surfaces in chronic eczema present an appearance 

 resembling lichen ; the hair is shed, or the sparse covering left is rigid 

 and patchy ; the skin is thickened, dry, and squamous, often has a 

 granular or verrucous appearance in consequence of hypertroph}^ of the 

 papillae, and is usually deeper in colour than that of neighbouring 

 parts. 



The process produces hardening (sclerosis) of the skin, and leads to 

 hyperplastic and atrophic changes ; the cells of the dermis, the glands, 

 and the capillary follicles gradually undergo change, and may partially 

 disappear. In spite of exfoliation of the superficial layers of the epi- 

 dermis this portion of the skin remains of considerable thickness. 



As in the acute form, circumscribed patches are sometimes seen 

 which remain obstinate, and very rebellious to treatment. In the 

 dorso-lumbar region eczema often extends over very large spaces, and 

 in old-standing cases produces excessive thickening and folding of the 

 skin. In the limbs the disease affects the elbows, hocks, and digital 

 region ; in some animals it ends by producing suppurative dermatitis, 

 marked by the formation of numerous little abscesses containing blood- 

 stained pus, and offering almost the same appearance as follicular 

 mange. Eczema of the tail sometimes extends to the greater part of 

 this region, or appears as a large number of small disseminated areas, but 

 is most frequently localised at the extremity, the skin covering which is 

 inflamed and swollen, and its superficial layer ulcerated, whence the 



