134 THE DUCTLESS GLANDS 



malignant disease, and extravasation of blood have been 

 recorded. The solar plexus and semilunar ganglia as well as 

 the ganglia and nerves in the adrenals are often the seats of 

 alterations. They may be atrophied from the pressure of 

 tumours, affected by tuberculosis by extension or as part of a 

 widespread invasion, or they may be involved in inflammatory 

 processes (Dock). 



Hyperplasia of lymphoid tissues has been described. 



Wiesel has described in six cases of Addison's disease severe 

 degenerative changes and destruction of the chromaphil cells 

 not only in the adrenal medulla, but also in the sympathetic. 

 He reports, further, that in a case of tuberculosis of both 

 adrenal bodies, where there had been no symptoms of Addison's 

 disease, not only was there no destruction, but there was a 

 hyperplasia of the chromaphil tissues. Wiesel then, regards 

 Addison's disease as due to a primary lesion of the chromaphil 

 tissues. It is clear that such cases were easily overlooked by 

 the earlier pathologists, and may account for some of the 

 reports of Addison's disease without lesion of the adrenals. 



6. Paihogeny. 



The theories as to the pathogeny of Addison's disease may 

 be divided into two groups : (1) Nervous, (2) chemical or 

 glandular. 



If we except Addison's original view (which he somewhat 

 modified later on) and the theory that the adrenals are of no 

 importance in the economy, most of the early theories were 

 nervous. The view of Wilks and Greenhow was that the 

 lesion is special and primary in the adrenals, while the symp- 

 toms of the disease are due to the secondary effects on the 

 adjacent sympathetic, the solar plexus, and the semilunar 

 ganglia. But in many cases of typical Addison's disease no 

 changes in nervous structures could be found, and on the 

 other hand there are numerous examples of irritation of 

 sympathetic ganglia where no symptoms of Addison's disease 

 have occurred. It may be, however, that the vomiting is of a 

 nervous nature, and due to some effect upon the autonomic 

 nervous system. 



The chemical or glandular theory is the one now generally 

 accepted. It is usually subdivided into two : (1) The auto 

 intoxication theory ; and (2) the theory of internal secretion. 



I 



