264 MANUAL OF EQUINE MEDICINE. 



Active congestion constitutes the first stage of inflammation 

 of the kidneys, or nephritis. It sometimes occurs as the 

 result of acute fevers, and may be induced by the ingestion 

 of certain irritants, as turpentine and cantharides, or by the 

 action of cold and damp. 



Passive or mechanical congestion depends upon venous ob- 

 struction from pulmonary or cardiac disease. 



When examined, the kidneys are seen to be enlarged and 

 engorged with blood. 



If the congestion, especially when mechanical, be of long 

 duration, important structural changes of a chronic inflam- 

 matory nature may follow. 



Eenal congestion is usually attended with a scanty secre- 

 tion, and if very severe, there may be a quantity of albumen, 

 blood, and a few renal casts, but otherwise there are few or 

 no general symptoms by which this affection may be 

 diagnosed. 



Treatment. — When dependent upon other aff'ections, 

 renal congestion must not be treated apart from the general 

 disease. 



In other cases, rest, laxatives, and the application of 

 warm fomentations to the loins are all that is required. 



INFLAMMATION OF THE KIDNEYS— NEPHRITIS. 

 — Inflammation of the kidneys, or nephritis {vlcppovy the 

 kidney), is of rare occurrence in the horse. 



In acute nephritis, as in all acute inflammations, the 

 cellular structure of the organ is chiefly involved, whereas 

 when this passes on to the chronic form the changes are 

 more especially marked in the interstitial tissues. 



Inflammation of the pelvis of the kidney, or pyelitis 

 (TugXof, pelvis), except when resulting from the irritation 

 of a calculus, is of rare occurrence in the horse. Professor 

 Williams mentions a case of pyelitis in a foal two days 

 old, which died of acute suppurative arthritis. 



