BULLOUS DERMATITIS: PEMPHIGUS. 



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this exanthema, which is extremely rare in our animals. Intense 

 irritations, whose nature is still unknown, undoubtedly act upon 

 the integument in a manner similar to bullous traumatiG, thermie 

 (burns) or chemical (cantharides) dermatitis. 



Symptoms. In consulting veterinary publications, we do not 

 find any good description of the manifestations of this dermatosis. 

 Loiset has described an enzootic eruption in the ox, characterized by 

 spherical or ovoid bullae, measuring as much as ten centimetres in 

 circumference, appearing on the croup, the loins, and posterior mem- 

 bers ; they were filled with a transparent liquid ; a short time after 

 their formation they were torn, the moist surfaces thus produced 

 w^ere then covered with scabs, the skin became desquamated, re- 

 covery took place rapidly; for some time some shining blotches could 

 be seen to persist at the place where the vesicles had disappeared. 

 Seaman recognized an entirely similar eruption on the ox, which 

 was accompanied by chills and fever. Dieckerhoff observed a bul- 

 lous dermatitis which was characterized by flat or slightly rounded 

 vesicles, from the dimensions of a walnut to a saucer, which were 

 developed on the skin of the abdomen, head, neck, shoulders, and 

 thorax of five horses ; some contained a clear and limpid liquid 

 like water, others a yellowish matter. Most of these would burst 

 within a few days, producing moist secreting surfaces ; the patients 

 seemed to experience much itching. 



These forms of bullous dermatitis, which seem entirely different 

 from varicella, show a striking analogy with acute pemphigus of 

 man, a disease the etiology and nature of which are yet imperfectly 

 known — some considering it as an acute infectious disease, others 

 as a vasomotor neurosis, others as a dermatomycosis. The cases 

 described in the ox much resemble pemphigus vulgaris of man, a 

 benign disease, which is quite different from pemphigus foliaceus, 

 which often causes death. 



Besides the large characteristic vesicle of bullous dermatitis, some 

 authors have found in the horse, upon the lips and nostrils, a spe- 

 cific vesiculous eruption which has been described under the name 

 offbeat pimples'' (Haubner) and herpes labialis. This exanthema 

 is characterized by small agminated vesicles, of the size of a lentil, 

 and which contain a transparent liquid. They become rapidly rup- 

 tured and cicatrize under a scabby envelope. 



We must admit that this specific vesiculous eruption, which is 

 located preferably in the neighborhood of natural openings, shows 



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