862 Eczema. 



Ill itching of the skin the integument at most shows only 

 the effects of scratching, while changes in the skin itself are 

 wanting. Acne in horses (socalled summer or heat rash, etc.) 

 is distinguished from eczema by the occurrence of large, but not 

 crowded, nodules between which the skin appears normal; at 

 the same time sensitiveness to pressure is more pronounced 

 than itching at the originally affected spots, and the disease 

 heals in a short time. Dermatitis pustulosa contagiosa in con- 

 trast to eczema is characterized by its highly contagious nature 

 and b}^ the formation of small vesicles on roundish elevated 

 spots of the sldn, after their bursting gummy scabs form; 

 itching is entirely absent. Erythema of the fetlock may be dis- 

 tinguished from eczema by its transient nature, but it may de- 

 velop into eczema if neglected. Necrotic inflammation of the 

 skin of the fetlock (socalled necrotic "greasy heels") may be 

 differentiated from eczematous greasy heel by the character of 

 its s}^nptonls. Herpes tonsurans and favus may be distin- 

 guished from seborrheic eczema by their contagious nature, 

 also by the joresence of fungous elements round about the hair 

 or in the superficial layers of the skin (sometimes difficult to 

 prove), also by the fact that in herpes tonsurans the hairs break 

 oif closely at the orifice of the hair follicles or above, and in 

 favus they appear dull and brittle, whilst in seborrheic eczema 

 they fall out entirely; in favus also the peculiar character of 

 the scabs is an important distinguishing factor. 



Traumatic inflammations of the skin also enter into con- 

 sideration in the diagnosis of eczema, but here the skin always 

 undergoes a more or less deep destruction of tissue and a layer 

 of skin of variable thickness mortifies, the inflammatory changes 

 developing more by way of a reaction. Besides, suppuration 

 is more frequent in this affection, while nodules, vesicles and 

 23ustules do not form. 



Variola can only be mistaken for eczema in the initial 

 stage or towards the end of the affection, otherwise the initial 

 fever, the outbreak of the complaint over a large area of the 

 body as well as the very characteristic appearance of the large 

 vesicles should prevent error. The exanthema of distemper 

 begins with the appearance of red spots followed by larger 

 greenish colored flat pustules, after their rupture wrinkled dry 

 deposits form; moisture is trivial and itching is, as a rule, 

 completely absent. Foot-and-mouth disease may simulate inter- 

 trigo, yet its typical course, a similar eruption in the mouth and 

 the contagious-infectious character of the complaint, especially 

 on comparison of several cases of the disease, should furnish 

 sufficient diagnostic points, besides the skin trouble is not so 

 diffuse and uniform as in intertrigo. 



Finally in those cases where the eczema is associated with 

 anemia and cachexia, the cause of the bad nutrition must be 

 investigated, besides a possible disease of the digestive organs 



