e;:tki)i;ki:ssi\-m tissue ciiancics. 227 



CALCAREOUS INFILTRATK iX. 



DEVIXITION. 

 ETIOLOGY. 



Jliij^aircd circulalioii. 



Rickets. 



Iiito.vicalioii, Mcniiry c'c 

 I'ARIETIRS. 



Tissue St^aees — Calculi. 



Tissue 

 TISSUE AEECETED 

 EFFECTS. 



Calcaredus infiltration is a conditii n in which lim ; salts are 

 deposited in abnormal locations or excessive quantities are 

 deposited in those tissues in whicli calcareous depositions nor- 

 mallv occur. 



In the formation of osseous tissue, certain definite quantities 

 of lime salts impregnate the softer formative tissue, tlius produc- 

 ing typical bone. Considerable (piantities of lime salts normally 

 occur in the blood and lymph of the various animals. The urine 

 of the horse, donkey, and mule frecpiently contains such large 

 amounts of calcium phosphate that it is cpiite turbid when ex- 

 creted. Excessive cpiantities of lime salt in solution predispose 

 to calcareous infiltration as well as to calculus formation. 



The lime salt most frequcntlv found in tissues affected with 

 calcareous infiltration is the carbonate, though other salts of 

 lime ma\' be present as the phosphate and rarely, the suljihate. 

 These salts are all insoluble in water, alcohol, ether and chloro- 

 form, as well as most other solvents. The application of dilute 

 acids tisualh' cause excessive effervescence because of the lib- 

 eration of carbon-dioxide. 



Pathologic calcareous infiltration sometimes occurs in dense 

 scar or cicatricial tissue as in extreme cases of poll evil, fistu- 

 lous withers or quittors ; in necrotic areas as tubercles of tuber- 

 culosis in cattle and hogs ; in necrotic areas of arteries affected 

 with atheromatous degeneration; in inspissated pus; in the sup- 

 porting framework of the lungs producing pneumono-koniosis ; 

 in the kidnev ; and in other organs in chronic bichloride of mer- 

 cur}^ poisoning; in parasitic cysts, as the trichina cysts in hogs, 

 and psorosperm cysts ; and in dead foetuses. 



Etiology. — Imperfect eirculation.— T\\hQrcx\\a.r lesions (tubercles') 

 are nonvascular and invariably become calcified sooner or later. Al- 

 though tubercles are nonvascular, there is more or less enzy- 

 motic action taking place resulting in the liberation of carbon 

 dioxide ; there are variable quantities of fluid containing lime 



