﻿IX. B, 3 Boynton: Kidney-worm Infestation of Swine 279 



embryonic type of connective tissue and the youngest blood 

 vessels were found around the edges of the lobules, while the 

 connective tissue which extended out from the edges appeared 

 to be older; this showed that it was encroaching upon the 

 parenchymatous tissue and crowding it out. Large numbers 

 of round cells and eosinophiles were present along the borders 

 of the lobules, and a few were scattered throughout the new- 

 forming connective tissue. 



From the foregoing, it is evident that the worm produces 

 an irritation which gives rise to proliferation of connective at 

 the expense of parenchymatous tissue, the former causing 

 pressure upon, and atrophy and degeneration of, the latter. 



There was also marked proliferation of the bile ducts in these 

 areas. They developed in some instances to such an extent 

 as to present the appearance of an adenoma. In those areas 

 in which the parenchymatous tissue had been completely obliter- 

 ated by the intruding connective tissue, many of the numerous 

 blood vessels which were formed during the development of 

 the connective tissue had undergone thrombosis. Thrombi in 

 all stages of organization were found. In many instances, 

 these thrombi appeared as cords of connective tissue completely 

 occluding the small vessels. 



In those areas which the worms had but recently invaded, 

 the fibrous connective tissue capsule surrounding them was found 

 in different degrees of development. The earliest stages showed 

 merely a few cells of new-forming tissue, rich in blood vessels 

 and infiltrated with a large number of leucocytes. In the older 

 lesions, there was a well-defined, thick wall of connective tissue. 

 The liver tissue around the newly infested parts showed a 

 marked passive congestion. Also, the liver cells in these 

 areas were shrunken to a perceptible extent from pressure 

 caused by dilated capillaries, and they showed various grades 

 of degeneration. 



LYMPH GLANDS 



Various appearances were noticed in the lymph glands accord- 

 ing to the extent to which they had undergone pathological 

 changes. The earliest change was an active congestion. The 

 cortical follicles, especially in the neighborhood of the lymph 

 sinuses, were markedly congested, and merged in many instances 

 into haemorrhagic areas. The cortical substance was distended- 

 The lymphoid tissue was scattered, and the intervening spaces 

 were filled with blood. In the medullary portion of the glands, 

 the tissue was distended and loose, except the lymphatic cords 



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