ADDENDA TO THE DISEASES OF THE KIDNEYS. 



39.3 



Etiolog-y. The cause of cystitis is especially due to irritation of 

 the vesical mucous membrane by toxic or infectious matters arising 

 from the blood, and which are eliminated with the urine (can- 

 tharides, essence of turpentine, fungi). That which is produced 

 during the course of serious infectious diseases belongs to this group. 

 It may also be occasioned by a common cold, by an inflammation 

 of the surrounding tissues (nephritis, pyelitis, urethritis, vaginitis, 

 peritonitis, metritis, etc.), which has extended to the bladder by 

 contiguity or continuity of tissues, by causes of a traumatic order 

 (wounds and contusions of the mucous membrane, vesical calculi, 

 catheterization), or by local infection (unclean sound). Retention 

 of urine in the bladder (frequent in pet dogs), compression of the 

 urethra, constrictions, contractions (paralysis of the muscular sys- 

 tem), spasm of the canal, etc., easily produce a catarrhal or narcotic 

 cystitis in consequence of the decomposition of the urine and the 

 action of the septic matters upon the vesical mucous membrane. 



[The action of cold upon trophic nerves and prolonged retention 

 of urine are influences which, combined, often produce this disease. 

 In cases in which house dogs, unaccustomed to the action of cold,, 

 are for some reason exposed to it, as for instance in railway travel, 

 when confined in close quarters, they will retain their urine for 

 quite long periods, and thus frequently results in an attack of 

 cystitis. — w. L. z.] 



Pathological anatomy. The alterations vary with the degree 

 of inflammation. Cystitis may adopt the following forms : the ca~ 

 tarrhaly purulent, croupous, diphtheric, necrotic, hemorrhagic, chronic^ 

 hyperplastic, with a varicose dilatation of the vessels, phlegmasic, 

 with submucous or pericystic abscess, or even perforation of the 

 bladder, and lastly, it may be incrusted, the urinary salts being 

 deposited upon the mucous membrane. In the common catarrhal 

 form the mucous membrane is tumefied, red, covered with an exu- 

 date composed of mucus, epithelial cells, and isolated white cor- 

 puscles ; in the purulent form this exudate is exclusively composed 

 of white corpuscles. Chronic cystitis is characterized by thickening 

 of the mucous membrane, by warty vegetations of that membrane, 

 varicose distention of its vessels, or calcareous incrustation (frequent 

 in the mare and ox). In croupous and diphtheric forms the 

 mucous membrane is sometimes covered by a necrotic membranous 

 exudate, at other times it is strewn with ulcerations produced by 

 the elimination of the sloughs. 



