THE THYROID AND PARATHYROID GLANDS 



797 



tissue often containing fat in its deeper layers ; the hands and feet become 

 unshapely; the lips thick and the tongue somewhat enlarged, so that 

 when the person attempts to speak, it appears as if the tongue were too 

 large for the mouth ; the hair falls out ; there is a low body temperature, 

 and it can be shown that the energy metabolism is greatly depressed, and 

 that there is a deficiency in oxygen consumption. It is said the person can 

 take a larger quantity of sugar than an ordinary individual without the 

 development of glycosuria, but the depression of the metabolic function 

 causes the patient to take sparingly of food, in spite of which, however, 

 the body weight may steadily increase. The sexual function becomes 

 depressed, and there is involvement of the nervous system as shown by 

 mental dullness and lethargy. 

 Although the thyroid gland is much atrophied in myxedema, symptoms 



A. B. 



Fig. 197. A, Case of myxedema; B, Same after seven months' treatment. (From Tigerstedt.) 



that are very similar may also occur when the gland is enormously en- 

 larged. As already explained, however, this enlargement is due merely 

 to an accumulation of colloidal material and is really an atrophic con- 

 dition. A patient suffering from endemic goiter may at first exhibit 

 symptoms which are usually attributed to a hypersecretion of thyroid 

 material into the blood (the symptoms will be described immediately), 

 but later these give place to symptoms not unlike those of myxedema. 

 It is concluded that the above conditions are due to deficiency of 

 thyroid function, or hypothyroidism, because: (1) the gland is atrophied, 

 and (2) similar symptoms to those exhibited by the clinical conditions 



