530 DISEASES OF THE KIDNEYS. 



From J to 1 drachm of digitalis in powder, or better still an injection 

 of from 5 milligrammes to 1 centigramme of digitaline may also be given 

 when dyspnoea is very great and is accompanied by anasarca. Medicines 

 such as oil of turpentine and considerable doses of nitrate of potash, 

 however, are contra-indicated. 



CHRONIC NEPHRITIS 



True chronic nephritis, i.e., a condition strictly limited to the renal 

 tissue, and unaccompanied by pyelitis, is still little known among our 

 domestic animals. The symptoms characterising it have not always 

 been carefully noted, and the diagnosis is very often uncertain. Never- 

 theless, one of the most common forms has been carefully studied by 

 Seuffert, viz., chronic hypertrophic nephritis. 



Causation. Chronic nephritis is the common sequel to the acute 

 forms, whatever their origin, but it may also occur primarily from 

 repeated chills produced by such conditions as exposure to heavy con- 

 tinued rain when at grass, chills contracted during cold nights and 

 the great variations in temperature in spring and autumn. The con- 

 ditions, however, thus produced are rather of the nature of subacute 

 nephritis than of chronic nephritis, properly so called. 



These forms of chronic nephritis may also occur primarily in con 

 sequence of chronic hepatic lesions with pressure on the posterior vena 

 cava, producing blood stasis in the kidneys. Finally, they may repre- 

 sent the delayed effects of slight lesions which have escaped notice and 

 have developed during grave diseases or as a consequence of repeated 

 gestation. 



From the anatomico-pathological standpoint, the only conditions 

 hitherto recognised are the chronic hypertrophic forms of nephritis 

 (large, white sclerotic kidney with lardaceous degeneration and some- 

 times marbling). This is probably because the animals are slaughtered 

 as soon as they suffer in condition, but if they were kept long enough 

 they would undoubtedly suffer also from the atrophic chronic forms of 

 nephritis found in man and in the dog. In the case of man observation 

 has shown that these two forms only represent different stages in the 

 development of one disease, the large, hypertrophied kidney of the early 

 stages afterwards undergoing marked progressive atrophy. 



The symptoms are at first so vague that diagnosis would be 

 impossible on a single examination. Seuffert states that the condition 

 develops as follows : — 



The first sign, loss of appetite, is soon followed by constipation and 

 dull colic, due to congestion of the kidney ; the pain is often so grep.t 

 as to cause intermittent groaning. 



