THE THYROID AND PARATHYROIDS 291 



Tachycardia is the most important cardio- vascular symptom. 

 A rapid pulse with the patient at rest in the absence of some 

 other obvious cause should always arouse suspicion of Graves's 

 Disease. In the later stages of the disease auricular fibrillation 

 may occur. 



Of the cutaneous symptoms, profuse sweating, especially of 

 the palms of the hands and soles of the feet, is the most impor- 

 tant. 



Diarrhoea, nausea, and vomiting also occur. Accelerated 

 respiration and shallow breathing are suggestive symptoms! 



Among the nervous symptoms a marked fine tremor, and 

 restlessness are the most noticeable. Goetsch's test consists in 

 an injection subcutaneously of a small quantity of adrenin. 

 The effect on the pulse rate, the tremor, the blood-pressure, 

 and the subjective nervous symptoms, is closely watched. 

 Acceleration of metabolism is an important feature of Graves's 

 Disease. Though the patients eat large quantities of food they 

 continue to grow emaciated. It is now customary to estimate 

 these changes in metabolism by a study of the basal metabolic 

 rate, by which is meant the minimum heat production when 

 at rest. This is estimated by an analysis of the end products 

 of metabolism, more especially the amount of oxygen used, and 

 of Co 2 given off. 



In Graves's Disease there may be a rise in basal metabolism 

 of 50 or 60 per cent. 



There may be distinct lymphocytosis as a result of implica- 

 tion of the thymus. 



With regard to the pathology of Graves's Disease, it has been 

 discussed whether the primary lesion is in the nervous system 

 or in the thyroid gland. There are certainly changes in the 

 thyroid, though it is not yet absolutely certain that these are 

 constant. It has been shown by Halsted and Edmunds that 

 if a portion of the thyroid be removed from an animal, the 

 remainder shows certain peculiar changes, described as com- 

 pensatory hypertrophy. The vesicles become irregular or 

 stellate in shape, the lining membrane is folded, the epithelium 

 is proliferated, and the micro -chemical reactions of the secre- 

 tion are altered so that it stains badly. Now, these changes 

 are practically identical with those found in Graves's Disease. 

 According to Marine, an enormous proportion of stray dogs 

 in Cleveland, Ohio, are thus affected, though they do not show 



